essay on power quality

Open Power Quality

A beginner's guide to power quality.

Power quality is a very complex subject, but to understand the overall goals of the Open Power Quality project, a simplified understanding should suffice.

Voltage, frequency, and "perfect" power quality

In OPQ, we are concerned with measuring the quality of power from a wall outlet, which means we focus on an approach to providing a kind of power called "alternating current" (AC). The following image illustrates what "perfect" quality AC power for U.S. wall outlets might look like:

This image illustrates three criteria that must be satisfied for AC power in US households to have "perfect" power quality:

• The voltage must vary from a maximum value of +170 volts to a minimum value of -170 volts.
• The voltage must switch between the maximum and minimum values exactly six times in a tenth of a second, or 60 times per second.
• The voltage must vary between its maximum and minimum values in a precise manner called a sine wave.

Even though voltage does not have a constant value in alternating current, it is useful to have a measurement consisting of a single number for voltage. By convention, a measure called "root mean square" (RMS) is used to represent the voltage in an alternating current, as it generally corresponds to the "average" value of the voltage. RMS Voltage for AC turns out to be approximately 70% of the maximum voltage, so the RMS voltage in our example is 170 Volts * 0.7 = 120 Volts. Put another way, if power is specified as 120 Volts RMS, then the voltage is actually varying between +170 Volts and -170 Volts. In the remainder of this discussion, we will use "Volts" as a shorthand for "RMS Voltage".

The rate at which the voltage switches back and forth between its maximum and minimum values in alternating current is called its "frequency", and the unit of measurement is called "hertz" (Hz). In this illustration, the voltage switches back and forth 60 times per second, which is measured as 60 Hz.

So, in the US, the standard for power from a wall outlet is 120 volts, 60 Hz AC. (Parenthetically, other countries have different standards. Australia uses 240 Volts, 50 Hz AC. Japan uses 100 Volts but some regions use 50 Hz AC while others use 60 Hz AC. For a full list, see List of Worldwide AC Voltages and Frequencies ).

Types of power quality problems

For the purposes of OPQ, power fails to achieve "perfect" quality when one or more of the three criteria listed above fails to hold. Here are examples of how each of the three criteria can fail to be satisfied:

• If the max/min voltage is significantly less than +170/-170, the result is a power quality problem known as a "voltage lag".
• If the voltage varies between its maximum and minimum values more than 60 times per second, the result is known as a "frequency surge".
• Various situations can result in the insertion of "harmonics" into the power line, or voltage sine waves that are multiples of 60 Hz. These various waves combine together to form a new wave that is a distortion of the desired sine wave. "Total Harmonic Distortion" is a measure of the level of distortion of the voltage sine wave due to this problem.

Most power quality problems relate to deviations in voltage. For example, the PurePower company created an illustrated list of ten common power quality problems , nine of which involve voltage-related issues:

As you can also see from this list, power quality problems are typically characterized by two things: (1) a change to the waveform, and (2) how long the change lasts. For example, a "transient" only lasts a matter of nanoseconds, while a "brownout" lasts at least a few minutes.

IEEE 1156 provides a characterization of voltage-related power quality problems which focuses only on the deviation of voltage from normal values and the duration of the deviation:

There are several power quality measures not currently calculated by OPQ Box, including power factor , telephone influence factor , flicker factor , and unbalance factor . Future research will determine if these metrics are important to achieving the goals of this project.

Causes of power quality problems

So, we know what constitutes "perfect" AC power, and we know the some of the common ways power can fail to achieve it. But why isn't power always perfect?

Causes of frequency deviations

First, let's look at frequency. As noted above, in perfect AC power in the US, voltage swings from +170 volts to -170 volts exactly 60 times a second. To understand why deviations in this frequency might occur, it is helpful to understand how this frequency value is established and maintained.

For large electrical grids, the frequency of AC power is defined by the speed of rotation of large AC generators, typically 3600 RPM for gas turbines. As demand for power fluctuates on a second by second basis, the speed of rotation will speed up or slow down in response, but utilities have become very good at maintaining the rotational velocity of their AC generators in the face of normal fluctuations in demand. So, for frequency to deviate significantly from 60 Hz, normal control procedures must have failed to keep the generators at their standard RPM. This can happen, for example, if demand for power exceeds the limits of the utility's capacity to provide it, or if sections of the grid suddenly disconnect from the main power sources.

Thus, because frequency is established and controlled at the source of power generation, substantial deviations from normal frequency values are traditionally rare in large electrical grids where most power is centrally generated and controlled by the utilities.

Interestingly, the rise of distributed renewable energy generation means that frequency deviation has the potential to become a bigger issue. If a substantial percentage of the power being provided to the grid is not provided by the large AC generators, then they might cease to dominate the way frequency is established and maintained.

Causes of voltage deviations

As noted above, voltage sags and swells are brief deviations from the normal swing in amplitude of the AC sine wave. By "brief", we mean from milliseconds to a second or so in duration. Fundamentally, voltage deviations occur when power generation into the grid does not match power consumption from the grid.

In contrast to frequency, which is established and controlled at the origin of power generation, voltage sags and swells can be caused at the end point of the electrical grid where the power is being consumed. Voltage sags can be caused by rapid increases in loads due to things like short circuits, motors starting, or electric heaters turning on. They can also be caused by household appliances drawing too much power in either your or your neighbour’s homes. Voltage swells can be caused by an abrupt reduction in load on a circuit, or by faulty wiring such as a damaged or loose neutral connection.

Distributed renewable energy sources like rooftop solar have the potential to cause local voltage sags and swells because they are generating power and placing it into the grid. If the utilities cannot control their centralized generation appropriately, then power consumption will not match power generation and a voltage sag or swell will result.

Transients can be caused by loose connections, lightning strikes, strong winds causing lines to clash, trees touching the line, vehicle accidents involving powerlines, or birds or other animals on the lines.

Industry standards

Not surprisingly, various standards have been developed to characterize power quality. Here are some of the most prominent.

IEEE 1159: Recommended Practice for Monitoring Electric Power Quality provides an overview of power quality monitoring, including descriptions of power quality phenomena, objectives for power quality monitoring, types of monitoring instruments, and various best practices for conducting power quality monitoring and interpreting the results.

ITIC (and CBEMA) Curves

The Information Technology Industry Council (ITIC) has created a standard (called the "ITIC Curve") that specifies what kinds of power quality problems should be tolerated by electronic devices. The latest version of this standard was published in 1999, and it defines what kinds of voltage fluctuations should be tolerated by electronic devices. Basically, for very short periods of time, very large deviations from normal voltage should be tolerated, but as the length of time of the deviation increases, the amount of deviation that should be tolerated decreases:

Note that this standard is simply a recommendation, and there is no requirement that electronic devices actually observe this tolerance to voltage deviations. The ITIC Curve is a revision of the similar standard called the "CBEMA Curve" developed by the Computer Business Equipment Manufacturers Association in the 1970's.

SEMI, the industry association for the semiconductor industry, developed a standard with similar goals to the ITIC Curve called SEMI F47-0706 . It sets minimum voltage sag immunity requirements.

There are many reasons why power quality might be monitored for problems. For example, electrical utilities monitor power quality in order to ensure the correct functioning of the grid. A manufacturing plant may monitor power quality in order to ensure that its equipment will not receive harmful power, and even to ensure that its equipment is not introducing harmful power problems into the grid. The kinds of power quality monitors used, and the data that is collected, depend upon the goals of the user.

In the case of OPQ, we are gathering power quality data to support goals such as the following:

(1) Consumer awareness of the potential impact of their power supply on their electronics. For example, computers are subject to data errors, crashing, or even destruction as a result of voltage deviations such as transients. This damage can be immediate, or the cumulative impact of multiple transients over time. OPQ increases consumer awareness about whether poor power quality could be a cause of any electronic problems they are experiencing.

(2) Impact on policies regarding distributed renewable energy. As noted above, incorporation of large amounts of distributed renewable energy can have adverse effects on both frequency and voltage. OPQ provides a novel, easy to deploy mechanism for gathering data about the quality of power, which can be used in conjunction with other data sources (network topology, solar insolation, wind speeds, other environmental factors) to improve modeling and thus ensure that renewable energy sources are being used as much as possible.

More about electricity monitoring

The folks over at Open Energy Monitor have produced an excellent tutorial on AC Power which goes into resistive vs reactive loads and real vs. reactive vs. apparent power.

Information

• Author Services

Initiatives

You are accessing a machine-readable page. In order to be human-readable, please install an RSS reader.

All articles published by MDPI are made immediately available worldwide under an open access license. No special permission is required to reuse all or part of the article published by MDPI, including figures and tables. For articles published under an open access Creative Common CC BY license, any part of the article may be reused without permission provided that the original article is clearly cited. For more information, please refer to https://www.mdpi.com/openaccess .

Feature papers represent the most advanced research with significant potential for high impact in the field. A Feature Paper should be a substantial original Article that involves several techniques or approaches, provides an outlook for future research directions and describes possible research applications.

Feature papers are submitted upon individual invitation or recommendation by the scientific editors and must receive positive feedback from the reviewers.

Editor’s Choice articles are based on recommendations by the scientific editors of MDPI journals from around the world. Editors select a small number of articles recently published in the journal that they believe will be particularly interesting to readers, or important in the respective research area. The aim is to provide a snapshot of some of the most exciting work published in the various research areas of the journal.

Original Submission Date Received: .

• Active Journals
• Find a Journal
• Proceedings Series
• For Authors
• For Reviewers
• For Editors
• For Librarians
• For Publishers
• For Societies
• For Conference Organizers
• Open Access Policy
• Institutional Open Access Program
• Special Issues Guidelines
• Editorial Process
• Research and Publication Ethics
• Article Processing Charges
• Testimonials
• Preprints.org
• SciProfiles
• Encyclopedia

Journal Menu

• Energies Home
• Aims & Scope
• Editorial Board
• Reviewer Board
• Topical Advisory Panel
• Instructions for Authors
• Special Issues
• Sections & Collections
• Article Processing Charge
• Indexing & Archiving
• Editor’s Choice Articles
• Most Cited & Viewed
• Journal Statistics
• Journal History
• Journal Awards
• Society Collaborations
• Conferences
• Editorial Office

Journal Browser

• arrow_forward_ios Forthcoming issue arrow_forward_ios Current issue
• Vol. 17 (2024)
• Vol. 16 (2023)
• Vol. 15 (2022)
• Vol. 14 (2021)
• Vol. 13 (2020)
• Vol. 12 (2019)
• Vol. 11 (2018)
• Vol. 10 (2017)
• Vol. 9 (2016)
• Vol. 8 (2015)
• Vol. 7 (2014)
• Vol. 6 (2013)
• Vol. 5 (2012)
• Vol. 4 (2011)
• Vol. 3 (2010)
• Vol. 2 (2009)
• Vol. 1 (2008)

Find support for a specific problem in the support section of our website.

Please let us know what you think of our products and services.

Visit our dedicated information section to learn more about MDPI.

Advanced Techniques for Power Quality Improvement

• Print Special Issue Flyer
• Special Issue Editors

Special Issue Information

• Published Papers

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section " F: Electrical Engineering ".

Deadline for manuscript submissions: closed (31 March 2022) | Viewed by 22529

Share This Special Issue

Special issue editor.

Power quality has a major impact on global economic activities. Problems related to power quality are currently responsible for generating serious damages in terms of operating losses, compromised personal safety, additional production costs, etc. Efficient energy management depends directly on a good knowledge of the disturbances affecting the power quality. Recent research works have investigated and improved power quality by developing advanced identification and control methods. Improving the quality of the power involves intelligent control laws based on signal processing, artificial neural networks, fuzzy logic, model predictive control, linear–quadratic–Gaussian control, etc.

Applying advanced techniques to improve power quality in real-time applications is a challenging problem, and this Special Issue proposes to explore the latest advances.

Topics of interest include, but are not limited to:

• Power quality improvement using fuzzy logic and artificial neural networks
• Harmonics identification and frequency tracking with signal processing
• Control of active power filter (APF)
• Power factor correction
• Improving the performance of AC power systems in terms of reactive power management and transient stability
• Flexible alternating current transmission system (FACTS) for power transmission systems
• Advanced methods for fault detection and classification in power transmission lines
• Advanced methods for detection and classification of appliances and power quality monitoring

Prof. Dr. Djaffar Ould Abdeslam Guest Editor

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website . Once you are registered, click here to go to the submission form . Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• Power quality
• Power factor
• Harmonics identification
• Active filtering
• Energy monitoring
• Signal processing
• Artificial neural network
• Fuzzy logic

Published Papers (8 papers)

Jump to: Review

Graphical abstract

Jump to: Research

Further Information

Mdpi initiatives, follow mdpi.

Subscribe to receive issue release notifications and newsletters from MDPI journals

• IEEE Xplore Digital Library
• IEEE Standards
• IEEE Spectrum

Join IEEE Smart Grid for Free!

Power Quality in Grid-Connected PV Systems: Impacts, Sources, and Mitigation Strategies

Written by Talada Appala Naidu, Sajan K Sadanandan, and Tareg Ghaoud

Installed Photovoltaic (PV) capacity has been rising across the smart grid distribution systems to supply energy needs as worries grow about greenhouse gases. However, the high penetration of PVs could affect the operation and planning of distribution networks. Therefore, to ensure a consistent and high-quality supply of power for a long time under a decentralized grid setup, it is critical to preserve compatibility and stability between the grid and its connected equipment. Power quality is an essential factor for the reliability of on-grid PV systems and should not be overlooked. This article underlines the power quality concerns, the causes for harmonics from PV, and their mitigation strategies considering the scope of research on the effect of voltage/current harmonics from PV-inverters on the grid.

Power Quality Concerns

In terms of continuous supply, power quality refers to a collection of indications that reflect the characteristics of the sources of supply under typical operational circumstances of voltage and frequency. Power electronics devices in today's distribution networks can create major interruptions, affecting the power quality provided to consumers connected to the network [1]. Furthermore, research has shown that every 1% variation in voltage corresponds to a 1% difference in power utilization. As a result of these variables, utilities make every effort to maintain the voltage provided to your home within the acceptable range [2]. Even though power quality is not a new concept in power systems, it merits special attention in current grids for the reasons listed below:

• A drastic growth of non-linear loads and single-phase loads may negatively impact the power quality.
• In recent years, there has been an increase in sensitive (critical) loads and new operational procedures that may affect the power quality.
• According to the current scenario, there has been a significant increase in power electronics-based inverters connected to the grid due to the high penetration of Distributed Energy Resources (DERs).

Utilities in the LV/MV levels are now moving toward solar PV rooftop installations connected to the grid for greater usage of solar PV-generated electricity in the interest of green energy. These solar PV-inverters will continue to operate under various situations, including frequent low-level and highly fluctuating irradiance. As a result of these circumstances, PV inverters may inject harmonics voltages/currents, impacting the power quality at the Point Of Connection (POC), creating a new challenge for the distribution network. High-level harmonics lead to energy losses, reduce system capacity, deteriorate network components, and cause protection equipment to malfunction. More study on grid-connected PV systems is needed to understand the issues that come with large-scale installations from different PV inverter manufacturers. So, the study of harmonic emission sources and their mitigation strategies has been introduced in the following section.

Harmonics Emitted from PV-Inverters and Their Mitigation Methods

The cause of harmonics generation in PV-inverters and mitigation measures are emphasized in this section.

Source of Harmonics Generation

The most common conversion mechanism used in grid systems is an 'inverter' to feed the grid from diverse DC sources. DC sources that work at various dc voltages and power levels include batteries, super-capacitors, and photovoltaic (PV) arrays [3]. Apart from all the various DC sources, the PV arrays combined with inverters are relevant in this study. Because of the inverter's intrinsic nature, it creates harmonics in voltage and currents that are sent to the grid, which are undesirable. The reasons for the generation of voltage/current harmonics from PV inverters are as shown below:

• Pulse Width Modulation (PWM) approaches must function at a relatively high switching frequency to operate inverter switches (e.g., IGBTs), leading to significant emission of harmonics at the inverter output.
• Effects of DC side impedance: When a large inductance is used to connect at the DC side of the PV inverter for smoothening the DC current. This type of harmonic source behaves like a current source and is called a current-type harmonic source. Suppose a capacitance is used to connect at the DC side of the PV inverter for smoothening the DC voltage. This type of harmonic source behaves like a voltage source and is called a voltage-type harmonic source. Therefore, the inverter with an inductor or capacitor may act as a current source or voltage source with the harmonic contents [4].
• DC-link voltage: The irregular and intermittent nature of solar irradiation, i.e., the changes in the solar irradiance throughout the day, cause significant ripples in DC link voltage, thus producing the harmonics on the AC side of the inverter [5].

These are the most important reasons for PV inverter harmonic emission. However, the investigation into the various sources of harmonics created by PV inverters is still underway.

Power Quality Mitigation Strategies

It is crucial to maintain the power quality limits under the standard level according to the IEEE 519, IEEE 1547, and IEC 61000-3-2. Furthermore, a few related research studies on power quality mitigation measures are presented below as part of resolving the power quality challenges:

• A dynamic reactive power compensation thyristor-driven LC compensator that significantly reduces the injection of harmonic currents compared to typical static-var compensators has been reported in [6]. Even though an extra active filter (static-var compensator here) for harmonic compensation has been eliminated, the thyristor, L, and C circuitry are needed to compensate harmonics.
• Hossein et al. in [7] proposed a novel system approach for improving power quality in LV distribution networks utilizing a Unified Power Quality Conditioner. It consists of a power converter at the MV/LV substation's end, and another power converter at the customer's end, which increases the number of switches and requires an extra control circuit
• Alireza et al. [8] presented research on combining a transformer-less hybrid series active filter and energy storage system to provide enhanced power quality. The researchers also found that the requirement of an energy storage system for providing constant supply is an extra cost for the compensation of power quality issues.
• A Phase-locked loop (PLL) based reactive power flow regulation for the control of PV system in LV distribution network has been proposed in [9]. In this work, the harmonic compensation function is included in the inverter control system, which improves power quality at POC.

From the literature presented above, power quality disturbances at POC are being addressed by compensators that use different inverter circuits and control techniques. It is also identified that the inverter control system itself includes the function of harmonic compensation. So, it is suggested to develop such control techniques for the existing inverter to control and improve the power quality issues at POC.

This article examines the major power quality issues of on-grid PV systems and the necessity to study the harmonics emitted from PV inverters. Voltage/current harmonic emissions have always been given special attention because they potentially impact vital components and technology of on-grid PV systems. This article also provides an insight into why power quality is a concern, precisely the source of harmonic generation and the available mitigation strategies in the literature. From the discussion above, we can conclude that further studies need to be conducted on the following topics:

• Improved controllers in active power filters, inverters, and other power electronics devices which are required to enhance power quality on on-grid inverters connected systems.
• Sophisticated metering, sensing, and control features are required to support improving power quality delivered to customers with an acceptable power quality level.
• To understand the challenges due to large-scale installation from different manufacturers of PV inverters, more research, investigation on harmonic emission from PV-inverters, control circuits within multiple brands, and types of these inverters in grid-connected PV systems is needed.
• It is also recommended to develop control strategies that work for existing PV inverters to improve the power quality issues at POC.
• Arash Anzalchi, Aditya Sundararajan, Amir Moghadasi, and Arif Sarwat. "High-penetration grid-tied photovoltaics: Analysis of power quality and feeder voltage profile." IEEE Industry Applications Magazine 25, no. 5 (2019): 83-94.
• "Smart grid and power quality" SMART ENERGY Consumer Collaborative
• Syed M. Ahsan and Hassan A. Khan. "LV Harmonic Analysis of Single-Phase Rooftop Solar PV Systems with Non-Linear Loads." In 2022 IEEE Green Technologies Conference (GreenTech) , pp. 1-6. IEEE, 2022.
• Dayi Li and Jun Tian, "A novel active power filter for the voltage-source type harmonic source," In 2008 International Conference on Electrical Machines and Systems , pp. 2077-2080. IEEE, 2008.
• Jianxia Sun and Cheng Lin, "Calculation and Spectral Analysis of DC-Link Current for three phase PWM inverter." In 2021 21st International Symposium on Power Electronics (Ee) , pp. 1-6. IEEE, 2021.
• Lei Wang, Chi-Seng Lam, and Man-Chung Wong, "Design of a thyristor-controlled LC compensator for dynamic reactive power compensation in smart grid," IEEE Transactions on Smart Grid 8, no. 1 (2016): 409-417.
• Hossein Hafezi, Gabriele D'Antona, Alessio Dedè, Davide Della Giustina, Roberto Faranda, and Giovanni Massa, "Power quality conditioning in LV distribution networks: Results by field demonstration," IEEE Transactions on Smart Grid 8, no. 1 (2016): 418-427.
• Alireza Javadi, Abdelhamid Hamadi, Auguste Ndtoungou, and Kamal Al-Haddad, "Power quality enhancement of smart households using a multilevel-THSeAF with a PR controller," IEEE Transactions on Smart Grid 8, no. 1 (2016): 465-474.
• Ángel Molina-García, Rosa A. Mastromauro, Tania García-Sánchez, Sante Pugliese, Marco Liserre, and Silvio Stasi, “Reactive power flow control for PV inverters voltage support in LV distribution networks,” IEEE Transactions on Smart Grid 8, no. 1 (2016): 447-456.

This article was edited by Cesar Duarte.

To view all articles in this issue, please go to June 2022 eBulletin . For a downloadable copy, please visit the IEEE Smart Grid Resource Center .

Talada Appala Naidu is Post-Doctoral Researcher at R&D Center, Dubai Electricity & Water Authority (DEWA), Dubai, UAE. He received his Bachelor of technology from JNTU, Kakinada, India. He received Master of technology and PhD from SV National Institute of technology, Surat, India in 2016 and 2020 respectively. He has been worked as visiting researcher at APEC Lab, Khalifa University, Abu Dhabi, UAE and then as an Adhoc Faculty at National Institute of technology, Andhra Pradesh, India. His research interests include the applications of power electronics in distribution systems, power quality, Artificial intelligence in control of power electronics devise, grid connected PV systems, and smart grid systems.

Sajan K Sadanandan  is an Associate Principal Researcher-Power System Lead at R&D Center, Dubai Electricity & Water Authority (DEWA), Dubai, UAE. In the past years, he has worked in a different capacity at IIT Roorkee, University of Petroleum and Energy Studies (UPES), GE India Industrial Private Limited, Washington State University, and West Virginia University. He received the Ph.D. and M.Tech degrees in electrical engineering from the Indian Institute of Technology Roorkee, India, in 2010 and 2016, respectively, and a B.Tech degree in electrical engineering from Pt. Ravi Shankar Shukla University, India in 2007. His research interests include power system operation and control, synchrophasors applications, and cyber-physical analysis of power systems.

Tareg Ghaoud is leading the Smart grid integration team within the DEWA R&D centre, DEWA, UAE. He is a utility industry expert with research interest in the integration and adoption of smart grid systems, and data analytics in the power transmission and distribution sectors. Tareg is a Chartered Engineer with over 20 years of industry experience. He worked as a delivery project manager and an R&D product owner for innovative projects serving the UK utility industry. He has intensive experience in the development and delivery of SCADA and automation systems for the power transmission and distribution networks, substation control systems and the development of digital grid solutions for providing grid analytics, flexibility solutions such as: microgrids, virtual power plants and Active Network Management (ANM). Tareg has led international teams of different size and capabilities and delivered projects using the V-Model as well as the Agile-Scrum methodology approaches. He completed his studies in the UK and holds a DPhil degree in Engineering Science from the University of Oxford (2002), an MSc degree in Control Systems from the Imperial College of Science, Technology and Medicine (1997), and a BEng degree in Control Engineering from the University of Sussex (1992).

To have the Bulletin delivered monthly to your inbox, join the IEEE Smart Grid Community.

Join IEEE Smart Grid

Past Issues

To view archived articles, and issues, which deliver rich insight into the forces shaping the future of the smart grid. Older Bulletins (formerly eNewsletter) can be found  here.  To download full issues, visit the publications section of the  IEEE Smart Grid Resource Center .

IEEE Smart Grid Bulletin Editors

Binesh Kumar

Managing Editor

Abhishek Joshi

Assistant Managing Editor

Mehrdad Rostami 

Interim Managing Editor

IEEE Smart Grid Publications Editorial Board

Mehdi Moghadasi Mehmet Cintuglu Geev Mokryani Jose Medina Merhrdad Boloorchi Vigna Kumaran Hossam Gaber Jorge Angarita Ali Nabavi  Vijay Sood Julio Usaola   Cesar Duarte   Gabriel Ordoñez   Jorge Martinez Jenny Zhou Click here for more info

Dr. Panayiotis (Panos) Moutis Editor-in-Chief IEEE Smart Grid Bulletin

IEEE Smart Grid Bulletin Compendium

The IEEE Smart Grid Bulletin Compendium "Smart Grid: The Next Decade" is the first of its kind promotional compilation featuring 32 "best of the best" insightful articles from recent issues of the IEEE Smart Grid Bulletin and will be the go-to resource for industry professionals for years to come. Click here to read "Smart Grid: The Next Decade"

power quality improvement Recently Published Documents

Total documents.

• Latest Documents
• Most Cited Documents
• Contributed Authors
• Related Sources
• Related Keywords

Fuzzy particle swarm optimization control algorithm implementation in photovoltaic integrated shunt active power filter for power quality improvement using hardware-in-the-loop

Aes-fll control of res powered microgrid for power quality improvement with synchronization control, power quality improvement of distribution power networks using capacitor-less h-bridge inverters for voltage regulation, power quality improvement in smart distribution grid using low-cost two-level inverter dvr, power quality improvement for grid-connected photovoltaic panels using direct power control.

This chapter displays a control strategy for a photovoltaic system (PV) linked to the network with two phases of a PWM converter, where the first phase is a DC-DC converter linked among the photovoltaic source and the DC-AC converter. The second phase is a DC-AC converter linked to the grid. The maximum power point (MPP) is tracked by DC-DC converter, which increases the DC bus voltage. The P&O (perturbation and observation) technique is utilized as a direct current (DC-DC) converter controller to make the PV arrays work at greatest value of power under changing weather conditions. The DC-AC converter transfers the maximum power extracted from the PV cell into the grid. To improve the energy quality produced by the photovoltaic field other than the performance of the pulse width modulation (PWM) inverter, direct power control (DPC) is used to achieve these improvements. The simulation results showed a good performance of the suggested controller. Decoupled power control is achieved successfully, and a good power quality with low harmonic distortion rate (THD) is obtained.

Performance evaluation of different configurations of system with DSTATCOM using proposed Icos⁡ϕ technique

The proposed Icos⁡ϕ control technique has been applied for power quality improvement using different configurations of system with distribution static compensator (DSTATCOM). Modeling, design and control of DSTATCOM are analysed in detial. Three phase reference current are extracted with this technique. The proposed technique has been used for power factor enhancement, voltage regulation, harmonic suppression and load balancing under dynamic condition with non-linear load. The proposed control is very effective for three different configurations of system with DSTATCOM for power quality improvement. Results for each configuration of system with DSTATCOM are simulated using MATLAB/Simulink sim power tool box. For teaching the power quality course, these can also be helpful.

Hybrid Renewable Energy Source Combined Dynamic Voltage Restorer for Power Quality Improvement

A simulation analysis of pv powered inc-cond mppt based hybrid filter for power quality improvement.

This paper proposed a Transformer less Hybrid Active Filter that upgrade the power quality in single-stage frameworks with steady renewable Photo Voltaic. It strengthens basic loads and carrying on as high-consonant impedance that does not below the critical loads. Manages energy management and power quality issues identified with electric transportation and concentrate on enhancing the electric vehicle load connected to grid. The control technique was intended to anticipation of current harmonic distortions with the nonlinear loads to control the flow of utility with no standard massive and expensive transformer. Power factor alongside AC side will likewise kept up to some esteem and furthermore dispense with the voltage distortions at the Common coupling point.

Assessment of Power Quality Improvement in a Micro WECS with Battery Storage under Critical Load Condition

A review on power electronics technologies for power quality improvement.

Nowadays, new challenges arise relating to the compensation of power quality problems, where the introduction of innovative solutions based on power electronics is of paramount importance. The evolution from conventional electrical power grids to smart grids requires the use of a large number of power electronics converters, indispensable for the integration of key technologies, such as renewable energies, electric mobility and energy storage systems, which adds importance to power quality issues. Addressing these topics, this paper presents an extensive review on power electronics technologies applied to power quality improvement, highlighting, and explaining the main phenomena associated with the occurrence of power quality problems in smart grids, their cause and effects for different activity sectors, and the main power electronics topologies for each technological solution. More specifically, the paper presents a review and classification of the main power quality problems and the respective context with the standards, a review of power quality problems related to the power production from renewables, the contextualization with solid-state transformers, electric mobility and electrical railway systems, a review of power electronics solutions to compensate the main power quality problems, as well as power electronics solutions to guarantee high levels of power quality. Relevant experimental results and exemplificative developed power electronics prototypes are also presented throughout the paper.

Export Citation Format

Share document.

Literature Review and Power Quality Issues

• First Online: 12 May 2023

Cite this chapter

• Amal M. Abd El-Hameid 5 ,
• Adel A. Elbaset   ORCID: orcid.org/0000-0002-0762-5180 6 ,
• Mohamed Ebeed   ORCID: orcid.org/0000-0003-2025-9821 5 &
• Montaser Abdelsattar 7  

196 Accesses

1 Citations

This chapter presents a comprehensive survey of distributed energy resources (DERs), including their types, their benefits, and the applied methods for assigning their optimal allocations and sizes, and also a comprehensive survey about the distribution flexible AC transmission systems(D-FACTS), including their types, their benefits, and the applied methods for assigning their optimal locations and sizes. This chapter also presents an overview of the distributed static compensator (D-STATCOM), including its topology, benefits, and the methods used for optimal integration of this device. An overview related to photovoltaic-based distributed generation (PV-DG) is presented, including its principal function, benefits, and the applied optimization methods for inclusion optimally. Also, the power quality issues and the power quality disturbances classification are presented comprehensively in this chapter.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

• Available as PDF
• Read on any device
• Instant download
• Own it forever
• Available as EPUB and PDF
• Compact, lightweight edition
• Free shipping worldwide - see info
• Durable hardcover edition
• Dispatched in 3 to 5 business days

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Similar content being viewed by others

A Detailed Review of the Optimal Distributed Generation Placement in Smart Power Distribution Systems

An Extensive Data-Based Assessment of Optimization Techniques for Distributed Generation Allocation: Conventional to Modern

Recent progress on the study of distributed economic dispatch in smart grid: an overview

G. Magdy, G. Shabib, A.A. Elbaset, Y. Mitani, A comprehensive digital protection scheme for low-inertia microgrids considering high penetration of renewables, in Renewable Power Systems Dynamic Security , (Springer, 2020), pp. 39–57

Chapter   Google Scholar  

S. Jazebi, S.H. Hosseinian, B. Vahidi, DSTATCOM allocation in distribution networks considering reconfiguration using differential evolution algorithm. Energy Convers. Manag. 52 , 2777–2783 (2011)

Article   Google Scholar  

S. Kamel, F. Jurado, D. Vera, A simple implementation of power mismatch STATCOM model into current injection Newton–Raphson power-flow method. Electr. Eng. 96 , 135–144 (2014)

G. Pepermans, J. Driesen, D. Haeseldonckx, R. Belmans, W. D’haeseleer, Distributed generation: Definition, benefits and issues. Energy Policy 33 , 787–798 (2005)

E.S. Oda, A.M. Abd El Hamed, A. Ali, A.A. Elbaset, M. Abd El Sattar, M. Ebeed, Stochastic optimal planning of distribution system considering integrated photovoltaic-based DG and DSTATCOM under uncertainties of loads and solar irradiance. IEEE Access 9 , 26541–26555 (2021)

R.O. Bawazir, N.S. Cetin, Comprehensive overview of optimizing PV-DG allocation in power system and solar energy resource potential assessments. Energy Rep. 6 , 173–208 (2020)

A.A. Elbaset, S.A.M. Abdelwahab, H.A. Ibrahim, M.A.E. Eid, Performance Analysis of Photovoltaic Systems with Energy Storage Systems (Springer, 2019)

Book   Google Scholar  

M.F. Akorede, H. Hizam, E. Pouresmaeil, Distributed energy resources and benefits to the environment. Renew. Sust. Energ. Rev. 14 , 724–734 (2010)

A.R. Gupta, A. Kumar, Deployment of distributed generation with D-FACTS in distribution system: A comprehensive analytical review. IETE J. Res., 1–18 (2019)

Google Scholar  

S.A. Taher, S.A. Afsari, Optimal location and sizing of DSTATCOM in distribution systems by immune algorithm. Int. J. Electr. Power Energy Syst. 60 , 34–44 (2014)

N. Salman, A. Mohamed, H. Shareef, Reliability improvement in distribution systems by optimal placement of DSTATCOM using binary gravitational search algorithm. Prz. Elektrotech. 88 , 295–299 (2012)

M. Sedighizadeh, A. Eisapour-Moarref, The imperialist competitive algorithm for optimal multi-objective location and sizing of DSTATCOM in distribution systems considering loads uncertainty. INAE Lett. 2 , 83–95 (2017)

D. Kaliaperumal Rukmani, Y. Thangaraj, U. Subramaniam, S. Ramachandran, R. Madurai Elavarasan, N. Das, L. Baringo, M.I.A. Rasheed, A new approach to optimal location and sizing of DSTATCOM in radial distribution networks using bio-inspired cuckoo search algorithm. Energies 13 , 4615 (2020)

P. Balamurugan, T. Yuvaraj, P. Muthukannan, Optimal allocation of DSTATCOM in distribution network using whale optimization algorithm. Eng. Technol. Appl. Sci. Res. 8 , 3445–3449 (2018)

A. Selim, S. Kamel, F. Jurado, Optimal allocation of distribution static compensators using a developed multi-objective sine cosine approach. Comput. Electr. Eng. 85 , 106671 (2020)

M. Mohammadi, M. Abasi, A.M. Rozbahani, Fuzzy-GA based algorithm for optimal placement and sizing of distribution static compensator (DSTATCOM) for loss reduction of distribution network considering reconfiguration. J. Cent. South Univ. 24 , 245–258 (2017)

K. Zou, A.P. Agalgaonkar, K.M. Muttaqi, S. Perera, Distribution system planning with incorporating DG reactive capability and system uncertainties. IEEE Trans. Sustain. Energy 3 , 112–123 (2011)

Q. Gong, J. Lei, J. Ye, Optimal siting and sizing of distributed generators in distribution systems considering cost of operation risk. Energies 9 , 61 (2016)

M. Ebeed, A. Alhejji, S. Kamel, F. Jurado, Solving the optimal reactive power dispatch using marine predators algorithm considering the uncertainties in load and wind-solar generation systems. Energies 13 , 4316 (2020)

M. Ebeed, A. Ali, M.I. Mosaad, S. Kamel, An improved lightning attachment procedure optimizer for optimal reactive power dispatch with uncertainty in renewable energy resources. IEEE Access 8 , 168721–168731 (2020)

M. Khajevand, A. Fakharian, M. Sedighizadeh, Stochastic joint optimal distributed generation scheduling and distribution feeder reconfiguration of microgrids considering uncertainties modeled by copula-based method. Iran. J. Electr. Electron. Eng. 16 , 371–392 (2020)

L. Luo, S.S. Abdulkareem, A. Rezvani, M.R. Miveh, S. Samad, N. Aljojo, M. Pazhoohesh, Optimal scheduling of a renewable based microgrid considering photovoltaic system and battery energy storage under uncertainty. J. Energy Storage 28 , 101306 (2020)

F.S. Abu-Mouti, M. El-Hawary, Optimal distributed generation allocation and sizing in distribution systems via artificial bee colony algorithm. IEEE Trans. Power Deliv. 26 , 2090–2101 (2011)

A. El-Fergany, Optimal allocation of multi-type distributed generators using backtracking search optimization algorithm. Int. J. Electr. Power Energy Syst. 64 , 1197–1205 (2015)

E. Ali, S.A. Elazim, A. Abdelaziz, Ant lion optimization algorithm for renewable distributed generations. Energy 116 , 445–458 (2016)

K. Ravi, M. Rajaram, Optimal location of FACTS devices using improved particle swarm optimization. Int. J. Electr. Power Energy Syst. 49 , 333–338 (2013)

O.P. Mahela, A.G. Shaik, A review of distribution static compensator. Renew. Sust. Energ. Rev. 50 , 531–546 (2015)

M. Mohammadi, M. Montazeri, S. Abasi, Bacterial graphical user interface oriented by particle swarm optimization strategy for optimization of multiple type DFACTS for power quality enhancement in distribution system. J. Cent. South Univ. 24 , 569–588 (2017)

N. Kanwar, N. Gupta, K. Niazi, A. Swarnkar, Improved cat swarm optimization for simultaneous allocation of DSTATCOM and DGs in distribution systems. J. Renew. Energy 2015 (2015)

T. Yuvaraj, K. Ravi, Multi-objective simultaneous DG and DSTATCOM allocation in radial distribution networks using cuckoo searching algorithm. Alex. Eng. J. 57 , 2729–2742 (2018)

S. Devi, M. Geethanjali, Optimal location and sizing determination of Distributed Generation and DSTATCOM using Particle Swarm Optimization algorithm. Int. J. Electr. Power Energy Syst. 62 , 562–570 (2014)

K. Devabalaji, K. Ravi, Optimal size and siting of multiple DG and DSTATCOM in radial distribution system using Bacterial Foraging Optimization Algorithm. Ain Shams Eng. J. 7 , 959–971 (2016)

T. Ackermann, G. Andersson, L. Söder, Distributed generation: A definition. Electr. Power Syst. Res. 57 , 195–204 (2001)

G. Allan, I. Eromenko, M. Gilmartin, I. Kockar, P. McGregor, The economics of distributed energy generation: A literature review. Renew. Sust. Energ. Rev. 42 , 543–556 (2015)

K. Angelopoulos, Book Title: Integration of Distributed Generation in Low Voltage Networks: Power Quality and Economics (ed: University of Strathclyde in Glasgow, 2004)

M.F. Akorede, H. Hizam, I. Aris, M.-Z.A.A. Kadir, Re-emergence of distributed generation in electric power systems: Incentives, values and issues. Energy Environ. 21 , 75–92 (2010)

F. Gonzalez-Longatt, C. Fortoul, Review of the distributed generation concept: Attempt of unification, in International Conference on Renewable Energies and Power Quality (ICREPQ 05), España , (2005), pp. 16–18

P. Chiradeja, Benefit of distributed generation: A line loss reduction analysis, in 2005 IEEE/PES Transmission & Distribution Conference & Exposition: Asia and Pacific , (2005), pp. 1–5

B.A. Kumar, A.A. Rao, Review on resolution of issues in reactive power and voltage STATCOM based distributed generation. J. Recent Trends Power Syst. 3 (2020)

Y. Gao, X. Meng, W. Gao, E. Long, A review of technologies and evaluation softwares for distributed energy source system. Procedia Soc. Behav. Sci. 216 , 398–408 (2016)

G. Magdy, E.A. Mohamed, G. Shabib, A.A. Elbaset, Y. Mitani, SMES based a new PID controller for frequency stability of a real hybrid power system considering high wind power penetration. IET Renew. Power Gener. 12 , 1304–1313 (2018)

J. Martin, Distributed vs. centralized electricity generation: Are we witnessing a change of paradigm, in An Introduction to Distributed Generation , (2009)

N.E. Musoni, Analysis of the Effect of Renewable Generation on the Power Quality of the Grid, Modelling and Analysis of Harmonic and Voltage Distortion (Cape Peninsula University of Technology, 2018)

Y.-C. Jeong, E.-B. Lee, D. Alleman, Reducing voltage volatility with step voltage regulators: A life-cycle cost analysis of Korean solar photovoltaic distributed generation. Energies 12 , 652 (2019)

A. Ghosh, G. Ledwich, Power Quality Enhancement Using Custom Power Devices (Springer, 2012)

J.F. Hauer, J.E. Dagle, Consortium for Electric Reliability Technology Solutions Grid of the Future White Paper on Review of Recent Reliability Issues and Systems Events (Pacific Northwest National Lab. (PNNL), Richland, WA, 1999)

A. Zangeneh, S. Jadid, A. Rahimi-Kian, A hierarchical decision making model for the prioritization of distributed generation technologies: A case study for Iran. Energy Policy 37 , 5752–5763 (2009)

G. Ault, J. McDonald, G. Burt, Strategic analysis framework for evaluating distributed generation and utility strategies. IEE Proc. Gener. Transm. Distrib. 150 , 475–481 (2003)

M. Zhang, L. Dai, Carbon nanomaterials as metal-free catalysts in next generation fuel cells. Nano Energy 1 , 514–517 (2012)

T. Khatib, W. Elmenreich, Modeling of Photovoltaic Systems Using Matlab: Simplified Green Codes (Wiley, 2016)

S.-K. Kim, J.-H. Jeon, C.-H. Cho, E.-S. Kim, J.-B. Ahn, Modeling and simulation of a grid-connected PV generation system for electromagnetic transient analysis. Sol. Energy 83 , 664–678 (2009)

M. Abd El Sattar, A.M. Abd El Hamed, A.A. Elbaset, M. Ebeed, Application of enhanced sine cosine algorithm for optimal allocation of PV-DG and DSTATCOM in distribution systems. Int. J. Eng. Manag. Res. 10 (3), 594–615 (2021)

R. Sirjani, A.R. Jordehi, Optimal placement and sizing of distribution static compensator (D-STATCOM) in electric distribution networks: A review. Renew. Sust. Energ. Rev. 77 , 688–694 (2017)

S. Elango, E.C. Sekaran, Mitigation of Voltage Sag by Using Distribution Static Compensator (D-STATCOM), in 2011 International Conference on Process Automation, Control and Computing , (2011), pp. 1–6

S.A. Taher, A.R. Afsari, Optimal allocation and sizing of dstatcom by immune algorithm in distribution networks including distributed generation. Soft Comput. J. 2 , 2–15 (2013)

A.R. Jordehi, Particle swarm optimisation (PSO) for allocation of FACTS devices in electric transmission systems: A review. Renew. Sust. Energ. Rev. 52 , 1260–1267 (2015)

M. Asensio, G. Muñoz-Delgado, J. Contreras, Bi-level approach to distribution network and renewable energy expansion planning considering demand response. IEEE Trans. Power Syst. 32 , 4298–4309 (2017)

P. Prakash, D.K. Khatod, Optimal sizing and siting techniques for distributed generation in distribution systems: A review. Renew. Sust. Energ. Rev. 57 , 111–130 (2016)

B. Sultana, M. Mustafa, U. Sultana, A.R. Bhatti, Review on reliability improvement and power loss reduction in distribution system via network reconfiguration. Renew. Sust. Energ. Rev. 66 , 297–310 (2016)

A.R. Jordehi, Particle swarm optimisation with opposition learning-based strategy: An efficient optimisation algorithm for day-ahead scheduling and reconfiguration in active distribution systems. Soft. Comput. 24 , 18573–18590 (2020)

A.R. Jordehi, Allocation of distributed generation units in electric power systems: A review. Renew. Sust. Energ. Rev. 56 , 893–905 (2016)

A.R. Jordehi, Brainstorm optimisation algorithm (BSOA): An efficient algorithm for finding optimal location and setting of FACTS devices in electric power systems. Int. J. Electr. Power Energy Syst. 69 , 48–57 (2015)

H.-J. Choi, J.-H. Jung, Enhanced power line communication strategy for DC microgrids using switching frequency modulation of power converters. IEEE Trans. Power Electron. 32 , 4140–4144 (2017)

F. Dastgeer, H.E. Gelani, A comparative analysis of system efficiency for AC and DC residential power distribution paradigms. Energ. Buildings 138 , 648–654 (2017)

Á. Molina-García, R.A. Mastromauro, T. García-Sánchez, S. Pugliese, M. Liserre, S. Stasi, Reactive power flow control for PV inverters voltage support in LV distribution networks. IEEE Trans. Smart Grid 8 , 447–456 (2016)

R. Majumder, Reactive power compensation in single-phase operation of microgrid. IEEE Trans. Ind. Electron. 60 , 1403–1416 (2012)

A. Elnady, M.M. Salama, Unified approach for mitigating voltage sag and voltage flicker using the DSTATCOM. IEEE Trans. Power Deliv. 20 , 992–1000 (2005)

Z. Shuai, A. Luo, Z.J. Shen, W. Zhu, Z. Lv, C. Wu, A dynamic hybrid var compensator and a two-level collaborative optimization compensation method. IEEE Trans. Power Electron. 24 , 2091–2100 (2009)

R. Yan, B. Marais, T.K. Saha, Impacts of residential photovoltaic power fluctuation on on-load tap changer operation and a solution using DSTATCOM. Electr. Power Syst. Res. 111 , 185–193 (2014)

M. Hosseini, H.A. Shayanfar, Regular paper modeling of series and shunt distribution FACTS devices in distribution systems load flow. J. Electr. Syst. 4 , 1–12 (2008)

M. Ebeed, S. Kamel, S.H.A. Aleem, A.Y. Abdelaziz, Optimal allocation of compensators, in Electric Distribution Network Planning , (Springer, 2018), pp. 321–353

T.L. Skvarenina, The Power Electronics Handbook (CRC Press, 2018)

A.A. Elbaset, H. Ali, M. Abd-El Sattar, Novel seven-parameter model for photovoltaic modules. Sol. Energy Mater. Sol. Cells 130 , 442–455 (2014)

A.A. Elbaset, H. Ali, M. Abd El Sattar, New seven parameters model for amorphous silicon and thin film PV modules based on solar irradiance. Sol. Energy 138 , 26–35 (2016)

T. Salmi, M. Bouzguenda, A. Gastli, A. Masmoudi, Matlab/simulink based modeling of photovoltaic cell. Int. J. Renew. Energy Res. 2 , 213–218 (2012)

A.A. Elbaset, H. Ali, M. Abd-El Sattar, M. Khaled, Implementation of a modified perturb and observe maximum power point tracking algorithm for photovoltaic system using an embedded microcontroller. IET Renew. Power Gener. 10 , 551–560 (2016)

C.-C. Chu, C.-L. Chen, Robust maximum power point tracking method for photovoltaic cells: A sliding mode control approach. Sol. Energy 83 , 1370–1378 (2009)

A.A. Elbaset, M. Hassan, H. Ali, Performance analysis of grid-connected PV system, in 2016 Eighteenth International Middle East Power Systems Conference (MEPCON) , (2016), pp. 675–682

W.B. Walker, E.M. Smith, T. Jan, L. Zwiebel, A functional role for Anopheles gambiae Arrestin1 in olfactory signal transduction. J. Insect Physiol. 54 , 680–690 (2008)

B.S. Bernanke, Report of the Editor: American economic review. Am. Econ. Rev. 94 , 501–513 (2004)

S. Liu, L. Wang, J. Tian, Y. Luo, X. Zhang, X. Sun, Aniline as a dispersing and stabilizing agent for reduced graphene oxide and its subsequent decoration with Ag nanoparticles for enzymeless hydrogen peroxide detection. J. Colloid Interface Sci. 363 , 615–619 (2011)

M. Eremia, C.-C. Liu, A.-A. Edris, Advanced Solutions in Power Systems: HVDC, FACTS, and Artificial Intelligence (Wiley, 2016)

A. Edris, Proposed terms and definitions for flexible AC transmission system (FACTS). IEEE Trans. Power Deliv. 12 (1997)

C. Liu, J. Masri, V. Perez, C. Maya, J. Zhao, Growth performance and nutrient composition of mealworms (Tenebrio molitor) fed on fresh plant materials-supplemented diets. Foods 9 , 151 (2020)

S. Moghaddas-Tafreshi, E. Mashhour, Distributed generation modeling for power flow studies and a three-phase unbalanced power flow solution for radial distribution systems considering distributed generation. Electr. Power Syst. Res. 79 , 680–686 (2009)

M. Emmanuel, R. Rayudu, Evolution of dispatchable photovoltaic system integration with the electric power network for smart grid applications: A review. Renew. Sust. Energ. Rev. 67 , 207–224 (2017)

R.M. Neve, K. Chin, J. Fridlyand, J. Yeh, F.L. Baehner, T. Fevr, L. Clark, N. Bayani, J.-P. Coppe, F. Tong, A collection of breast cancer cell lines for the study of functionally distinct cancer subtypes. Cancer Cell 10 , 515–527 (2006)

J.M. Solanki, S. Khushalani, N.N. Schulz, A multi-agent solution to distribution systems restoration. IEEE Trans. Power Syst. 22 , 1026–1034 (2007)

H. Johal, D. Divan, Design considerations for series-connected distributed FACTS converters. IEEE Trans. Ind. Appl. 43 , 1609–1618 (2007)

L. Gyugyi, Dynamic compensation of AC transmission lines by solid-state synchronous voltage sources. IEEE Trans. Power Deliv. 9 , 904–911 (1994)

J. Savier, D. Das, Impact of network reconfiguration on loss allocation of radial distribution systems. IEEE Trans. Power Deliv. 22 , 2473–2480 (2007)

J.P. Lopes, N. Hatziargyriou, J. Mutale, P. Djapic, N. Jenkins, Integrating distributed generation into electric power systems: A review of drivers, challenges and opportunities. Electr. Power Syst. Res. 77 , 1189–1203 (2007)

S.A. Papathanassiou, A technical evaluation framework for the connection of DG to the distribution network. Electr. Power Syst. Res. 77 , 24–34 (2007)

D. Divan, W. Brumsickle, R. Schneider, B. Kranz, R. Gascoigne, D. Bradshaw, M. Ingram, I. Grant, A distributed static series compensator system for realizing active power flow control on existing power lines, in IEEE PES Power Systems Conference and Exposition, 2004 , (2004), pp. 654–661

A.A. Elbaset, M.S. Hassan, Design and Power Quality Improvement of Photovoltaic Power System (Springer, 2017)

K. Suslov, N. Solonina, D. Gerasimov, Assessment of an impact of power supply participants on power quality, in 2018 18th International Conference on Harmonics and Quality of Power (ICHQP) , (2018), pp. 1–5

A. Delle Femine, D. Gallo, D. Giordano, C. Landi, M. Luiso, D. Signorino, Power quality assessment in railway traction supply systems. IEEE Trans. Instrum. Meas. 69 , 2355–2366 (2020)

W. Xu, X. Liu, Y. Liu, An investigation on the validity of power-direction method for harmonic source determination. IEEE Trans. Power Deliv. 18 , 214–219 (2003)

S. Khalid, B. Dwivedi, Power quality issues, problems, standards & their effects in industry with corrective means. Int. J. Adv. Eng. Technol. 1 , 1 (2011)

B.S. GOUD, B.L. Rao, An intelligent technique for optimal power quality enhancement (OPQE) in a HRES grid connected system: ESA technique. Int. J. Renew. Energy Res. 10 , 317–328 (2020)

N. Prakash, V. Balaji, M. Sudha, Power quality improvement of grid inter connected hybrid system using STATCOM. Int. J. Adv. Eng. Technol. 7 , 1225–1233 (2016)

S. Angalaeswari, M. Thejeswar, R.S. Poongodi, W.V. Basha, P. Sasikumar, Power quality improvement of standalone hybrid solar-wind power generation system using FACTS devices. Int. J. Adv. Res. Electr. Electron. Instrum. Eng., (An ISO 3297: 2007 Certified Organization), 3 (2014)

R.D. Singh, T.P. Kumar, K. Sumanth, Simulation of SRF based DSTATCOM with grid connected PV generation system using fuzzy logic controller for reactive power management. Int. J. Adv. Res. Electr. Electron. Instrum. Eng. 5 , 6493–6501 (2016)

D. Amoozegar, DSTATCOM modelling for voltage stability with fuzzy logic PI current controller. Int. J. Electr. Power Energy Syst. 76 , 129–135 (2016)

A. Moreno-Muñoz, Power Quality: Mitigation Technologies in a Distributed Environment (Springer, 2007)

C.A.G. Marques, D.D. Ferreira, L.R. Freitas, C.A. Duque, M.V. Ribeiro, Improved disturbance detection technique for power-quality analysis. IEEE Trans. Power Deliv. 26 , 1286–1287 (2011)

Download references

Author information

Authors and affiliations.

Electrical Department, Faculty of Technology and Education, Sohag University, Sohag, Egypt

Amal M. Abd El-Hameid & Mohamed Ebeed

Electrical Engineering Department, Faculty of Engineering, Minia University, El-Minia, Egypt

Adel A. Elbaset

Electrical Engineering, South Valley University, Qena, Egypt

Montaser Abdelsattar

You can also search for this author in PubMed   Google Scholar

Rights and permissions

Reprints and permissions

Copyright information

© 2023 The Author(s), under exclusive license to Springer Nature Switzerland AG

About this chapter

Abd El-Hameid, A.M., Elbaset, A.A., Ebeed, M., Abdelsattar, M. (2023). Literature Review and Power Quality Issues. In: Enhancement of Grid-Connected Photovoltaic Systems Using Artificial Intelligence. Springer, Cham. https://doi.org/10.1007/978-3-031-29692-5_2

Download citation

DOI : https://doi.org/10.1007/978-3-031-29692-5_2

Published : 12 May 2023

Publisher Name : Springer, Cham

Print ISBN : 978-3-031-29691-8

Online ISBN : 978-3-031-29692-5

eBook Packages : Energy Energy (R0)

Share this chapter

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

• Publish with us

Policies and ethics

• Find a journal
• Track your research

YOUR FINAL GRADE - GUARANTEED UK Essay Experts

Disclaimer: This is an example of a student written essay. Click here for sample essays written by our professional writers.

View full disclaimer

Any scientific information contained within this essay should not be treated as fact, this content is to be used for educational purposes only and may contain factual inaccuracies or be out of date.

Power quality problems

Reference this

INTRODUCTION

If you need assistance with writing your essay, our professional essay writing service is here to help!

METHODOLOGY

Our academic experts are ready and waiting to assist with any writing project you may have. From simple essay plans, through to full dissertations, you can guarantee we have a service perfectly matched to your needs.

Simulation Test System

Results and discussions.

• Propagated Fault Event
• Vulnerability of fault event

CONCLUSIONS

• M. F. M. Roger C. Dugan, H. W. Beaty, Electrical Power Systems Quality. New York: McGraw-Hill, 1996.
• "IEEE Std. 1159-1995," IEEE Recommended Practise for Monitoring Electric Power Quality, June 1995.
• "IEEE Std 1250-1995," IEEE Guide for Services to Equipment Sensitive to Momentary Voltage Disturbances, Mar 1995.
• M. H. J. Bollen, Understanding Power Quality Problems, in Voltage Sags and Interruptions: IEEE Press, 1999.
• E. F. P. R. o. P. 309801-1996, Distribution Power Quality Study.
• E. L. W. H., Ling G. Tu, H. Wayne Hong, W. Zhong, "An Intergrated Application for Voltage Sag Analysis," IEE Transaction On Power System, vol. 13, pp. pp 930-935, 1998.
• J. E. B. R. Billinton, "Distribution System Realiability Indices," IEE Transaction On Power System, vol. 13, pp. pp 930-935, 1989.
• R. Gnativ and J. V. Milanovi, "Voltage sag propagation in systems with embedded generation and induction motors," presented at Power Engineering Society Summer Meeting, 2001. IEEE, 2001.
• E. Y. Ahmet Serdar Yilmaz, "Behaviour of Embedded GEneration during The Voltage Sags in Distribution Networks," Academic Journals, 2009.
• M. L. Pirjo Heine, "Voltage Sag Distributions Caused by Power System Faults," IEE Transaction On Power System, vol. 18, 2003.
• R. V. A. J. Xu, V. Rajagopalan, "Propagation of Sag and Harmonics in Medium Voltage Distribution System," IEEE Power Engineering Society Winter Meeting, vol. Vol 4, pp. pp 2582-2587, Jan. 2000.
• J. Xu, R. V. Annamraju, and V. Rajagopalan, "Propagation characteristics of sag and harmonics in medium voltage distribution systems," presented at Power Engineering Society Winter Meeting, 2000. IEEE, 2000.
• D. P. K. I. J. Nagrath, Modern Power System Analysis, 2nd Edition ed. New Delhi, India: TATA McGraw-Hill, 1989.
• M. H. J. Bollen, "Characterisation of voltage sags experienced by three-phase adjustable-speed drives," Power Delivery, IEEE Transactions on, vol. 12, pp. 1666, 1997.

Cite This Work

To export a reference to this article please select a referencing stye below:

Related Services

Essay Writing Service

• Dissertation Writing Service

• Assignment Writing Service

DMCA / Removal Request

If you are the original writer of this essay and no longer wish to have your work published on UKEssays.com then please:

Our academic writing and marking services can help you!

• Find out more about our Essay Writing Service
• Undergraduate 2:2
• 7 day delivery
• Marking Service
• Samples of our Service
• Full Service Portfolio

Humanity University

Dedicated to your worth and value as a human being!

Related Lectures

Study for free with our range of university lectures!

• All Available Lectures

Freelance Writing Jobs

Looking for a flexible role? Do you have a 2:1 degree or higher?

Study Resources

Free resources to assist you with your university studies!

• Dissertation Resources at UKDiss.com
• How to Write an Essay
• Essay Buyers Guide
• Referencing Tools
• Essay Writing Guides
• Masters Writing Guides

Change Region / Country

Here you can choose which regional hub you wish to view, providing you with the most relevant information we have for your specific region. If your specific country is not listed, please select the UK version of the site, as this is best suited to international visitors.

United Kingdom

United States

United Arab Emirates

Saudi Arabia

Construction of a power quality and electrical equipment knowledge graph for equipment status assessment

• Liu, Huicong
• Zhang, Huaying
• Zhang, Hongzhao
• Sun, Ruichen
• Zhao, Jianfeng

In modern power systems, the condition of electrical equipment is vital for maintaining power grid stability and efficiency. This paper presents the construction of a comprehensive knowledge graph for power quality and electrical equipment, derived from Chinese web sources. This knowledge graph facilitates real-time monitoring, predictive maintenance, and informed decision-making for electrical equipment management. The study covers core technologies, including data acquisition through web crawling using Selenium, entity recognition using BiLSTM-CRF, and relation extraction using R-BERT. The practical architecture includes ontology design, data pre-processing, entity recognition, relation extraction, and knowledge graph construction. SPARQL queries enable complex analysis, and applications support power quality monitoring and equipment health assessment. The knowledge graph serves as a foundation for understanding power quality and equipment status in a Chinese context, emphasizing the relationship between power quality and equipment failure. Ongoing efforts will expand and refine the graph to enhance its value for power quality-based equipment status assessment.

Quality management Essay

• To find inspiration for your paper and overcome writer’s block
• As a source of information (ensure proper referencing)
• As a template for you assignment

Introduction

Problem and motivation, provisional title, analysis: google swot analysis, improvement options, recommendations.

Bibliography

Quality management activities in organizations are undertaken to ensure that quality in its products is achieved and maintained within an unacceptable budget 1 . It is an activity that is closely dependent on the feedback from the organization’s clients, thus the quality management concept involves establishing channels for relaying customer feedback for which it requires that they function properly through out 2 .

As a part of quality management, the feedback is taken and incorporated in the design of new products that are aimed at raising customer satisfaction. Quality management spans from creating a design and lifecycle plan for a product or service to its production and distribution.

The activity involves identifying and measuring process elements, doing performance analysis and applying continuous quality improvements on the products, services and systems of production and distribution.

In this paper, Google, the Internet search giant, is analyzed, and recommendations are made on how it can maintain as well as improve the quality of its products.

This is important for the company in maintaining and enhancing its exemplary performance as its pursues its mission, which is to create an Internet resource from which you can access any kind of information disregarding geographical borders 3 . Thus, the problem and motivation in this paper are quality and quality enhancement respectively.

The provisional title that describes the contents of this paper best is “Safeguarding and enhancing quality at Google”.

Brief Review of the related literature

As stated above, quality management activities in organizations are undertaken to ensure that quality in its products is achieved and maintained within an unacceptable budget. 4 The Quality management concept is enriched by eight management principles that are fundamental in improving the performance of an organization. 5

One of these principles is customer focus, which emphasizes to an organization its dependency on its customers and, therefore, highlights the need for it to understand and appreciate their current and future needs for which it should set out to meet. 6

When an organization achieves customer focus, it implies that it is necessary to know not only both its internal and external customers, but also their needs and quality standards. Another principle is leadership, which facilitates the establishment of unity of purpose among the personnel in an organization. 7 Unity of purpose in an organization is critical in the achievement of its quality objectives and goals.

Involvement of people is another principle that enriches the quality management concept. 8 In an organization, there is the need for its personnel from whatever level to be involved fully in benefiting the organization. The next principle is a process approach, which develops the idea that an organization’s objective is better realized when its activities and allied resources are managed as an organizational process. 9

The following principle is approaching management as a system so that efficiency and effectiveness in achievement of the organization’s goals are boosted. 10 Continual improvement is another factor that enriches the quality management concept. 11 This principle stresses the need to pursue continued improvement on its product or service to the organization.

Another principle is a factual approach to decision-making, which emphasizes on the need to base decision-making of the organization on data analysis and information. 12 The last principle is the organization having supplier relationships that are mutually benefiting as these increase the ability for it and its suppliers to add value to their product(s) or service(s). 13

SWOT analysis is a tool used in the managerial activities of corporate organizations that wish to attain stability and sustainability in the long-term. 14 Its use in corporate organization management is aimed at realizing long-term stability and sustainability, specifically in decision-making.

For a given corporate organization, a SWOT analysis procedure takes into account both its internal and external environment to reveal the organization’s strengths, weaknesses, opportunities and threats. The analysis of the corporate organization’s internal environment reveals its strengths and weaknesses whereas that of the external environment reveals its opportunities and threats.

Once the analysis is completed, the SWOT approach is such that a corporate organization will consolidate its strengths, do away with its weaknesses, seize its opportunities and counter its threats. The following is a SWOT analysis for Google Inc., which, as discussed, will reveal the company’s strengths, weaknesses, opportunities and threats.

Aims and objective of the research

In Google’s business model, the company believes in giving users an online experience that eventually leads to strong verbal marketing of the company and continually increasing Internet traffic directed to the company’s products. 15

The experience is embodied in services to users that are of the best and highest quality; thus, quality is a key issue in Google. The main aim and objective of the research done here is to come up with recommendations that are directed towards helping the company to maintain and enhance the quality of its products.

Statement of the design and methodology

Through a performance and SWOT analysis of Google, we understand the company’s operating environment, and why it is important for it to manage quality in its products.

Company Description

Google Inc. is one of the world’s most successful companies specializing in Internet technology. Originally co-founded by Larry Page and Sergey Brin, the company offers a unique Internet service for which it has established itself as a market leader. 16 Its mission is to provide an Internet resource from which you can access any kind of information disregarding geographical borders. 17

Google’s business model

Google‘s business model that reflects the company’s mission is unlike that of its competitors. The model stresses on giving users an online experience that eventually leads to strong verbal marketing of the company and continually increasing Internet traffic directed to the company’s products. 18

The experience is embodied in services to users that are of the best and highest quality. The business model has led Google to make major acquisitions of and alliances with other Internet technology companies that include Amazon, e-bay, Picasa, Keyhole and You Tube.

Google’s collaboration and mergers with other huge online firms make a part of a strategy aimed at ensuring the company always ahead of its business rivals. 19 These acquisitions and mergers have, however, seen the company deviate from its original business model since it has found itself in entirely new markets. Taking into account the source of its revenue, it can be said that Google is mainly an advertising company.

For Google, appealing to its customers means redefining both e-commerce and e-business. Given that its business model stresses on advertisements and provision of services to all the Internet users the company maintains a strategic interest with online markets and firms that attract huge Internet traffic.

Google’s 2010 performance analysis

In 2009, Google Inc. emerged as the worldwide market leader in Internet and mobile search advertising and saw the company ranked fourth by CNNmoney in its list of 100 best companies to work for in 2010. 20 Although not spared by the 2008/9 global financial crisis, the company managed not only to register profits but growth as well as during the period.

Google’s 2010 turnover was slightly under $30 billion, which was a 24% increase using 2009 as the base year. 21 Given the size of the company, the figure implies that the company registered huge growth.

The growth is attributed to an increase in click volumes by 18% and a rise in the cost per click by about 5%. 22 The rise in volume can be itself linked to continued development of the company’s network, remarketing and/or the increased use of the Smartphone and tablets.

A further analysis of the turnover reveals that the share of revenue accrued in the U.S remained at 52% whereas that accrued in the U.K slightly declined in the fourth quarter of the year by 2%. 23 However, these had no effect on the overall revenue pattern of the company that remained relatively unchanged. 24

Also remaining unchanged was how revenue was split: revenue generated from advertisements on Google’s own websites remained at 66% that from advertisement’s on the company’s third party websites remained at 30% and that from other sources remained at 4%. 25

Google’s strengths

Google’s SWOT analysis reveals its market as one of its strengths. 26 The marketing strategy in use at Google is unique to it and historically, is one of a kind in online technology. Google does not restrain its business ventures to its search engine but is continuously introducing new products into the market.

One of Google’s target markets is the portion of the world’s youth in search for information, fun, knowledge and who wish to be at per with their different environmental surroundings. The other target market is any individual who uses the company’s search engine as he or she knowingly or unknowingly generates revenue for the company indirectly.

The SWOT analysis reveals Google’s key technologies as another of its strengths. 27 One of the company’s key technologies is its search engine whose development process has seen it answer queries more accurately. The software technology incorporated in the search engine enables it perform computations and return results at very advanced speeds. This is unlike traditional search engines whose technology is not as time-sensitive.

The company to examine web content and rank it by level of importance uses Google’s PageRank TM technology boosted by over 200 signals. The architecture of PageRank TM technology is such that it can hold over 500 million variables that in turn can hold 2 billion terms.

Due to this architecture it is thus possible for the company to profile web pages and determine those of importance so that they are programmed to appear first on the result page. Google as extended its technology to include Hypertext-Matching Analysis, which performs a full content analysis of text web pages in an effort to return more accurate results for a given query.

The SWOT analysis reveals quality of its personnel as another of Google’s strengths. 28 Google recruitment policy targets individuals of outstanding academic achievements and high experience in the various fields not only of information technology but also of knowledge management.

Top managerial posts at Google are filled with individuals who have an MBA or a PHD in a field that is relevant in enabling the company achieve its mission. To underline further that indeed quality of personnel is another of Google’s strength it can be seen from data collected in 2008 that the company had the highest profit per employee amongst its rivals, which was estimated at $209,624.

This figure is further motivation to the employees who are inherently encouraged by the company’s organizational culture to give out their best for the benefit of the company.

The SWOT analysis reveals Google’s capital base and its revenue streams as another of its strengths. 29 10 years after Google was founded its capitalization rose phenomenally to £105 billion which was enough to replace Procter and Gamble from 5 th place on the US stock market.

As stated earlier the main source of Google’s income comes from advertisements done on its site and those done on its third party sites. In 2006, Google was estimated as earning about 30% more on an advert than Yahoo or any other of its rivals does.

Google’s Weaknesses

One of Google’s weakness as revealed by the SWOT analysis is the high rate at which the company receives CVs and Resumes. The rate at which Google’s receives CVs and Resumes is staggering. 30 These results in large volumes of these documents that make it difficult for the company to recruit the best applicants for available positions.

Another of Google’s weaknesses as revealed by the SWOT analysis is external employee turnover of its senior executives. 31 A number of top executives have left Google in favor of Facebook. This exodus of highly skilled personnel from Google can have devastating effects on its future. Furthermore, the company seems not to know how to contain the problem and ironically its proposed measure as aggravated the crisis further.

Another of the company’s weakness as brought out by the SWOT analysis is recruiting a lot of contactors. 32 This habit has led to hiring of contractors who only waste the company’s resources. This is an indication of poor staff recruitment plans and poor job description and evaluation plans.

Other weakness of Google are its feeble presence in the social networking market, arbitrary content, too much liquidity, stock problems, material that is heterogeneous, Anglo-Saxon focus, political issues, problems with stock and its inability to generate revenue form You Tube.

Google’s opportunities

An opportunity for Google as revealed by the SWOT analysis is its operating system. Google has set out on a mission to assert its dominance in the operating system market with the Chrome and Android operating systems. 33 The approach by Google is to introduce an operating system that uses applications directly from the Internet as opposed to the traditional approach of operating systems that reside on a PC.

Experts who see the Internet as the future of information technology support the approach. This step by Google is seen by some people as a challenge to the current operating system’s market leader, Microsoft.

Other opportunities for Google are new acquisitions and mergers, growth in Internet usage globally, using web content of higher value, reaching new user groups and content, offering a starting point that is easy and more usage of expensive content.

Google’s threats

A threat to Google as revealed by the SWOT analysis is the lawsuits it faces. 34 Yahoo, Amazon and Microsoft are some of the companies that have at different times filed lawsuits against Google. One of the lawsuits filed collectively by these three companies saw Google settle it with an amount of $125 million. Another threat that faces Google as per the SWOT analysis is the company’s failure to motivate its contract employees. 35

The contract employees are spread in different regions in the world. Other threats to Google are gradually raising competition, privacy issues on content ownership, new technologies, the social networking site Facebook, censorship possibility and the slowdown in ad-spend.

Continual improvement is one of the principles that enrich the quality management concept. The principle stresses the need for a product to be of the best and highest quality. To improve quality in a company like Google, the apt option would be for the company to pursue CQI, which is a recurring process. 36

Considering Google’s mission and how it plans to achieve it, a suitable procedure for improving quality in the company should be based on FMEA. To add weight to this decision, we consider that the company is continually developing products whose quality has to be improved with time.

FMEA was first used by NASA specifically for identifying risks and mitigating their effects; however, the procedure has recently become widespread in industries where it is critical in realizing process improvement. With FMEA, potential failures associated with a product are identified beforehand and action plans formulated to deal with them. 37

For a given product, the FMEA analysis process begins with identifying potential failures in it. In this step, it is critical to know the set requirements for the product. If potential failures are found, the second step in the procedure is determining the level of severity for each.

This is a process that requires a complete picture of the system. The third step in the analytic procedure is knowing the cause of the failures and working out what is known as the probability of occurrence. The fourth step in the analysis procedure is coming up with controls and weighing their effectiveness.

If the controls are associated with risks, it prioritizes them. The fifth and the final step in the analysis procedure is documenting the action plans formulated to deal with each of the risks identified in the previous step.

Another option for quality improvement available to Google is Six Sigma strategy, which is built from concepts derived from the statistics and quality engineering fields. 38 Six Sigma is a strategy whose objective is to enhance business success through managing and improving quality. The strategy being a variant of Deming’s Plan-Do-Check-Act Cycle is implemented through two methodologies, namely, DMAIC and DMADV.

In the DMAIC methodology, the first step in improving quality is defining the problems of the existing system taking into account customer opinions. The second step is performing measurements of the current and existing system and collecting data that is relevant to the problem tackled. The third step is analyzing the data collected in the second step to determine the causes of the problem(s) and their effects.

The fourth step is improving the current and existing system by implementing the recommendations made from studying the problem. The fifth step is controlling future state processes so as to ensure that deviations from the required quality standards are corrected before finding their way to finished product.

In the DMADV methodology, the first step in improving quality is designing goals that reflect or capture the opinions of the customers. The second step is measuring the current system and identifying CTQs. The fourth step is analysis and development of alternatives to the design.

The fifth step is optimizing the design developed and preparing it for verification. The fifth step is design verification where the design is tested, implemented and submitted to the project owners who initiated it.

A recommendation to Google is for the company to adopt an FMEA based approach to quality improvement. The main shortcoming of the FMEA approach is that the activity is quite costly to implement on each and every product. However, considering its benefits and Google’s capital base, cost is not really an issue.

A recommendation to Google is for the company to pursue quality improvement through the Six Sigma approach. The Six Sigma approach is in line with Google’s business model for it is aimed at enhancing business success through giving customers pleasant experiences achieved through products of high qaulity. 39

Chartered Quality Institute, “What is quality” CQI , 2011. Web.

CNNmoney, “100 best companies to work for”, Cable News Network, 2011. Web.

Darkwah, Kwaku. “SWOT analysis of Google”, Adesua Global , 2011. Web.

Duke University Medical Center, “What is quality Improvement”, Duke University Medical Center. Web.

Graeme Knowles, Six sigma (Ventus Publishing ApS, 2011) International organization for standardization, “Principle 1: Customer focus ”, ISO , 2011. Web.

International organization for standardization, “Principle 2: Leadership ”, ISO , 2011. Web.

International organization for standardization, “Principle 3: Involvement of people ”, ISO , 2011. Web.

International organization for standardization, “Principle 4: Process approach ”, ISO , 2011. Web.

International organization for standardization, “Principle 5: System approach to management ”, ISO , 2011. Web.

International organization for standardization, “Principle 6: Continual improvement”, ISO , 2011. Web.

International organization for standardization, “Principle 7: Factual approach to decision making”, 2011. Web.

International organization for standardization, “Principle 8: Mutual beneficial supplier relationships, ISO , 2011. Web.

International organization for standardization, “Quality management principles”, ISO , 2011. Web.

Investopedia, “ SWOT analysis ”, Investopedia ULC, 2011. Web.

John Gamble and Arthur Thompson, Essentials of Strategic Management: The quest for competitive advantage (Boston: McGraw Hill, 2009), 14.

Norris, Simon “Google’s performance in 2010”, Periscopix Ltd, 2011. Web.

Rex Black, Managing the testing process: practical tools and techniques for managing hardware and software testing . (Canada: Wiley Publishing, Inc., 2002)

Rose Kenneth, Project quality management: why, what and how. (Florida: Rose Publishing, 2005)

Wikiswot, “Google SWOT analysis”, Wiki swot, 2011. Web.

1 Rose, K. (2005), p. 41

2 Charterd Quality Institute. (2011), p. 1

3 Darwah, K. (2010), p.1

4 Rose, K. (2005), p. 41

5 International organization for standardization (2011), p.1

6 International organization for standardization (2011), p.1

7 International organization for standardization (2011), p.1

8 International organization for standardization (2011), p.1

9 International organization for standardization (2011), p.1

10 International organization for standardization (2011), p.1

11 International organization for standardization (2011), p.1

12 International organization for standardization (2011), p.1

13 International organization for standardization (2011), p.1

14 Investopedia (2011), p.1

15 Darwah, K. (2010), p.11

16 Gamble/Thompson (2009), p.14

17 Darwah, K. (2010), p.1

18 Darwah, K. (2010), p.11

19 Darwah, K. (2010), p.12

20 CNNmoney (2011), p. 1

21 Norris, S. (2011), p.1

22 Norris, S. (2011), p.2

23 Norris, S. (2011), p.3

24 Norris, S. (2011), p. 3

25 Norris, S. (2011), p. 4

26 Darkwah, K. (2010), p.14

27 Darkwah, K. (2010), p.19

28 Darkwah, K. (2010), p.20

29 Darkwah, K. (2010), p. 27

30 Darkwah, K. (2010), p. 27

31 Darkwah, K. (2010), p. 29

32 Darkwah, K. (2010), p. 30

33 Darkwah, K. (2010), p. 33

34 Darkwah, K. (2010), p. 39

35 Darkwah, K. (2010), p. 40

36 Duke Medical University Center (2005), p.1

37 Rex, B. (2002), p.25

38 Knowles, G. (2011), p. 12

39 Knowles, G. (2011), p.10 – p.13

• The History and Growth of Google
• How Google Governs the Internet
• Google's view on the future of business
• Difference between Leadership and Management
• An impossibility of objectivity in the world of humans
• Lean and agile operations
• Decision Making as an Essential Process of an Organization
• Decision-Making in Management
• Chicago (A-D)
• Chicago (N-B)

IvyPanda. (2019, May 15). Quality management. https://ivypanda.com/essays/quality-management-essay/

"Quality management." IvyPanda , 15 May 2019, ivypanda.com/essays/quality-management-essay/.

IvyPanda . (2019) 'Quality management'. 15 May.

IvyPanda . 2019. "Quality management." May 15, 2019. https://ivypanda.com/essays/quality-management-essay/.

1. IvyPanda . "Quality management." May 15, 2019. https://ivypanda.com/essays/quality-management-essay/.

IvyPanda . "Quality management." May 15, 2019. https://ivypanda.com/essays/quality-management-essay/.

Home — Essay Samples — Nursing & Health — Therapy — Being a Physical Therapist: A Journey of Healing and Connection

Being a Physical Therapist: a Journey of Healing and Connection

• Categories: Career Therapy

About this sample

Words: 747 |

Published: Jun 6, 2024

Words: 747 | Pages: 2 | 4 min read

Table of contents

The science of healing, the art of empathy, the power of human connection, empowerment and resilience.

Cite this Essay

Let us write you an essay from scratch

• 450+ experts on 30 subjects ready to help
• Custom essay delivered in as few as 3 hours

Get high-quality help

Prof. Kifaru

Verified writer

• Expert in: Life Nursing & Health

+ 120 experts online

By clicking “Check Writers’ Offers”, you agree to our terms of service and privacy policy . We’ll occasionally send you promo and account related email

No need to pay just yet!

Related Essays

5 pages / 2457 words

1 pages / 497 words

1 pages / 464 words

8 pages / 3463 words

Remember! This is just a sample.

You can get your custom paper by one of our expert writers.

121 writers online

Still can’t find what you need?

Browse our vast selection of original essay samples, each expertly formatted and styled

Related Essays on Therapy

Lamberton, LH., & Minor-Evans, L. (2018). Human Relations, Strategies for Success. 6th Edition. McGraw-Hill Canada.

Wilderness therapy, also known as outdoor or adventure therapy, is an innovative approach to mental health and well-being that harnesses the healing power of nature. This essay explores the profound psychological and physical [...]

Occupational therapy is a dynamic profession that aims to help individuals achieve independence and improve their quality of life through meaningful and purposeful activities. As I pursue a career in occupational therapy, I am [...]

Imagine a world where stress and tension melt away with just a touch. This captivating promise is at the heart of massage therapy, a practice that has been used for centuries to promote relaxation, alleviate pain, and improve [...]

“Transforming society by optimizing movement to improve the human experience.” (APTA). This is the American Physical Therapy Association (APTA) vision for all members and Physical Therapist. As a student, in a doctorate of [...]

Phlebotomy, the practice of drawing blood from a patient for diagnostic or therapeutic purposes, has a rich and storied history that spans thousands of years. What we now consider a routine medical procedure has evolved [...]

Related Topics

By clicking “Send”, you agree to our Terms of service and Privacy statement . We will occasionally send you account related emails.

Where do you want us to send this sample?

By clicking “Continue”, you agree to our terms of service and privacy policy.

Be careful. This essay is not unique

This essay was donated by a student and is likely to have been used and submitted before

Download this Sample

Free samples may contain mistakes and not unique parts

Sorry, we could not paraphrase this essay. Our professional writers can rewrite it and get you a unique paper.

Please check your inbox.

We can write you a custom essay that will follow your exact instructions and meet the deadlines. Let's fix your grades together!

Get Your Personalized Essay in 3 Hours or Less!

We use cookies to personalyze your web-site experience. By continuing we’ll assume you board with our cookie policy .

• Instructions Followed To The Letter
• Deadlines Met At Every Stage
• Unique And Plagiarism Free

Reference Examples

More than 100 reference examples and their corresponding in-text citations are presented in the seventh edition Publication Manual . Examples of the most common works that writers cite are provided on this page; additional examples are available in the Publication Manual .

To find the reference example you need, first select a category (e.g., periodicals) and then choose the appropriate type of work (e.g., journal article ) and follow the relevant example.

When selecting a category, use the webpages and websites category only when a work does not fit better within another category. For example, a report from a government website would use the reports category, whereas a page on a government website that is not a report or other work would use the webpages and websites category.

Also note that print and electronic references are largely the same. For example, to cite both print books and ebooks, use the books and reference works category and then choose the appropriate type of work (i.e., book ) and follow the relevant example (e.g., whole authored book ).

Examples on these pages illustrate the details of reference formats. We make every attempt to show examples that are in keeping with APA Style’s guiding principles of inclusivity and bias-free language. These examples are presented out of context only to demonstrate formatting issues (e.g., which elements to italicize, where punctuation is needed, placement of parentheses). References, including these examples, are not inherently endorsements for the ideas or content of the works themselves. An author may cite a work to support a statement or an idea, to critique that work, or for many other reasons. For more examples, see our sample papers .

Reference examples are covered in the seventh edition APA Style manuals in the Publication Manual Chapter 10 and the Concise Guide Chapter 10

Related handouts

• Common Reference Examples Guide (PDF, 147KB)
• Reference Quick Guide (PDF, 225KB)

Textual Works

Textual works are covered in Sections 10.1–10.8 of the Publication Manual . The most common categories and examples are presented here. For the reviews of other works category, see Section 10.7.

• Journal Article References
• Magazine Article References
• Newspaper Article References
• Blog Post and Blog Comment References
• UpToDate Article References
• Book/Ebook References
• Diagnostic Manual References
• Children’s Book or Other Illustrated Book References
• Classroom Course Pack Material References
• Religious Work References
• Chapter in an Edited Book/Ebook References
• Dictionary Entry References
• Wikipedia Entry References
• Report by a Government Agency References
• Report with Individual Authors References
• Brochure References
• Ethics Code References
• Fact Sheet References
• ISO Standard References
• Press Release References
• White Paper References
• Conference Presentation References
• Conference Proceeding References
• Published Dissertation or Thesis References
• Unpublished Dissertation or Thesis References
• ERIC Database References
• Preprint Article References

Data and Assessments

Data sets are covered in Section 10.9 of the Publication Manual . For the software and tests categories, see Sections 10.10 and 10.11.

• Data Set References
• Toolbox References

Audiovisual Media

Audiovisual media are covered in Sections 10.12–10.14 of the Publication Manual . The most common examples are presented together here. In the manual, these examples and more are separated into categories for audiovisual, audio, and visual media.

• Artwork References
• Clip Art or Stock Image References
• Film and Television References
• Musical Score References
• Online Course or MOOC References
• Podcast References
• PowerPoint Slide or Lecture Note References
• Radio Broadcast References
• TED Talk References
• Transcript of an Audiovisual Work References
• YouTube Video References

Online Media

Online media are covered in Sections 10.15 and 10.16 of the Publication Manual . Please note that blog posts are part of the periodicals category.

• Facebook References
• Instagram References
• LinkedIn References
• Online Forum (e.g., Reddit) References
• TikTok References
• X References
• Webpage on a Website References
• Clinical Practice References
• Open Educational Resource References
• Whole Website References

IEEE Account

• Change Username/Password
• Update Address

Purchase Details

• Payment Options
• Order History
• View Purchased Documents

Profile Information

• Communications Preferences
• Profession and Education
• Technical Interests
• US & Canada: +1 800 678 4333
• Worldwide: +1 732 981 0060
• Contact & Support
• About IEEE Xplore
• Accessibility
• Terms of Use
• Nondiscrimination Policy
• Privacy & Opting Out of Cookies

A not-for-profit organization, IEEE is the world's largest technical professional organization dedicated to advancing technology for the benefit of humanity. © Copyright 2024 IEEE - All rights reserved. Use of this web site signifies your agreement to the terms and conditions.