This document provides case studies of power quality surveys using a Model 3196 Power Quality Analyzer. Case Study 6 describes a voltage dip detected at a 200V distribution panel in a headquarters building over a measurement period. Four voltage dips caused by lightning were detected, with residual voltages ranging from 47Vrms to 82Vrms and periods ranging from 50ms to 117ms. The voltage dips occurred on the distribution network due to lightning strikes.
The document summarizes power quality issues including defects like under voltage, over voltage, dips, surges, blackouts, harmonics, and transients. It discusses who is responsible for ensuring power quality and some typical problems caused by defects. Solutions mentioned include surge protection, UPS systems, generators, filters, proper wiring, and load zoning. Assuring high quality power is challenging as electricity must flow continuously from generators to consumers via a shared infrastructure.
This presentation gives detailed information about power quality i.e. how poor power quality is caused? what are the parameters on which we measure power quality? how can we solve the problem of poor power quality? this presentation will give you all the answers.
Power quality refers to maintaining the electric power within acceptable tolerances to allow devices to function properly without loss of performance. It is defined by parameters such as voltage, frequency and purity of waveform. Poor power quality can be caused by issues like sags, swells, transients, harmonics and grounding problems. The susceptibility of electrical equipment depends on the weakest component. While all devices are susceptible to some degree, the goal is to balance maintaining adequate power quality with designing equipment to have sufficient immunity to power quality issues.
Definition of power Quality, power quality terminology, power quality issues, Susceptibility Criteria, Responsibility of supplier and users of elect power, Standards.
This document discusses various sources of transient over-voltages on power systems including capacitor switching and lightning. It describes how capacitor switching can cause oscillations that generate transient over-voltages. Lightning can also directly or indirectly introduce surges into power systems. The document outlines issues like magnification of transients at customer locations and ferroresonance that can occur. It discusses principles of overvoltage protection like limiting voltage and diverting surge current. Protection devices like surge arresters and transient voltage surge suppressors are described.
The document discusses various power quality problems such as harmonic distortion, voltage sags, swells, and interruptions. It then discusses solutions for power quality problems including maintaining grid adequacy, using distributed resources like distributed generation and energy storage, and implementing enhanced interface devices. The document also describes the operation of the Merus A-series Active Filter, which can be used to compensate for harmonics and reactive power in an electrical system.
Introduction: Definition & Reasons of Occurrence of following Voltage Dip, Brief voltage increases, Brief voltage interruption, Transients, Voltage Notches, Flickers, Distortion, Un-balance. Power Quality Indices,Limits of Harmonic Distortion according to IEEE, IEC, EN and NORSOK limits.Brief Introduction of Power quality Standards: IEC 61000-2-5,IEC 61000-2-1, IEC 1159 ( Categories of Power quality variation according to IEEE 1159 standard with their relevant Spectral content, Duration of occurrence & Magnitude)
Power quality issues arise from disturbances in the electric power supply that can negatively impact equipment. Common issues include voltage sags, swells, interruptions, harmonics, and spikes. Around 80% of problems originate from within industrial facilities due to large loads or improper wiring, while 20% come from external utility issues like weather events. Poor power quality can increase energy costs and cause equipment failures. Monitoring power quality helps identify disturbances and their sources to improve reliability and reduce costs. Various devices like filters, regulators, and compensators can help mitigate different power quality issues. Maintaining high power quality supports the economic operation of power systems and equipment.
The document summarizes power quality issues including defects like under voltage, over voltage, dips, surges, blackouts, harmonics, and transients. It discusses who is responsible for ensuring power quality and some typical problems caused by defects. Solutions mentioned include surge protection, UPS systems, generators, filters, proper wiring, and load zoning. Assuring high quality power is challenging as electricity must flow continuously from generators to consumers via a shared infrastructure.
This presentation gives detailed information about power quality i.e. how poor power quality is caused? what are the parameters on which we measure power quality? how can we solve the problem of poor power quality? this presentation will give you all the answers.
Power quality refers to maintaining the electric power within acceptable tolerances to allow devices to function properly without loss of performance. It is defined by parameters such as voltage, frequency and purity of waveform. Poor power quality can be caused by issues like sags, swells, transients, harmonics and grounding problems. The susceptibility of electrical equipment depends on the weakest component. While all devices are susceptible to some degree, the goal is to balance maintaining adequate power quality with designing equipment to have sufficient immunity to power quality issues.
Definition of power Quality, power quality terminology, power quality issues, Susceptibility Criteria, Responsibility of supplier and users of elect power, Standards.
This document discusses various sources of transient over-voltages on power systems including capacitor switching and lightning. It describes how capacitor switching can cause oscillations that generate transient over-voltages. Lightning can also directly or indirectly introduce surges into power systems. The document outlines issues like magnification of transients at customer locations and ferroresonance that can occur. It discusses principles of overvoltage protection like limiting voltage and diverting surge current. Protection devices like surge arresters and transient voltage surge suppressors are described.
The document discusses various power quality problems such as harmonic distortion, voltage sags, swells, and interruptions. It then discusses solutions for power quality problems including maintaining grid adequacy, using distributed resources like distributed generation and energy storage, and implementing enhanced interface devices. The document also describes the operation of the Merus A-series Active Filter, which can be used to compensate for harmonics and reactive power in an electrical system.
Introduction: Definition & Reasons of Occurrence of following Voltage Dip, Brief voltage increases, Brief voltage interruption, Transients, Voltage Notches, Flickers, Distortion, Un-balance. Power Quality Indices,Limits of Harmonic Distortion according to IEEE, IEC, EN and NORSOK limits.Brief Introduction of Power quality Standards: IEC 61000-2-5,IEC 61000-2-1, IEC 1159 ( Categories of Power quality variation according to IEEE 1159 standard with their relevant Spectral content, Duration of occurrence & Magnitude)
Power quality issues arise from disturbances in the electric power supply that can negatively impact equipment. Common issues include voltage sags, swells, interruptions, harmonics, and spikes. Around 80% of problems originate from within industrial facilities due to large loads or improper wiring, while 20% come from external utility issues like weather events. Poor power quality can increase energy costs and cause equipment failures. Monitoring power quality helps identify disturbances and their sources to improve reliability and reduce costs. Various devices like filters, regulators, and compensators can help mitigate different power quality issues. Maintaining high power quality supports the economic operation of power systems and equipment.
sachu technologies team provides comprehensive power quality analysis and can implement measures to bring power quality to acceptable standards. Improving power quality can bring significant financial benefits.
Poor power quality can damage sensitive equipment.
Poor power quality can lower productivity and also drive up energy costs.
Poor power quality can cause increased expenditure on electrical assets when plant or building expansion is necessary.
Poor power quality can impair the safety of electrical installations.
Design and Simulation of Generation of High DC Voltage using Cockcroft Walton...IRJET Journal
This document describes the design and simulation of a high voltage DC power supply using a Cockcroft-Walton voltage multiplier circuit. A 6-stage voltage multiplier circuit is simulated in MATLAB to generate 2kV DC output from a 230V AC input. The effects of changing load capacitance and wave shaping resistor values on the output impulse voltage are analyzed. Simulation results show the output voltage waveform matches the expected 2kV level. In conclusion, the MATLAB model demonstrates the ability of a Cockcroft-Walton circuit to effectively generate high DC voltages through voltage multiplication from a lower AC input.
Come join the area's leading power quality experts as we demonstrate and replicate common power quality issues, problems and solutions in today's industrial and commercial electrical environments.
Power quality refers to maintaining a steady supply of electric power that operates equipment properly without damage or stress. Deviations from the normal voltage can cause issues like brief power interruptions or dimming lights. Poor power quality costs US companies billions annually and negatively impacts energy efficiency. Common power quality issues include voltage variations, frequency variations, harmonic distortions, and low power factor, all of which increase energy consumption and equipment wear.
Power Quality Basics_Complex Compatibility_AclaraAclara
Power Quality is a major concern to utility customers and the utility. For the energy consumer, the economic impact of power disturbances can range from hundreds of dollars in equipment repair to millions of dollars in production losses and downtime. For utilities, disturbances lead to customer dissatisfaction and losses in load and revenue.
This presentation clarifies the unique electrical relationship between utility and customers relative to Power Quality. Introducing Power Quality terminology, tools to determine compatibility, and data that is available for analysis.
This document discusses power quality and methods to enhance it. It defines power quality and common power quality problems such as voltage sags, swells, transients, and harmonic distortion. It then describes several methods to solve power quality problems, including using hybrid filters, transformer methods, coil clocks, power factor correction, and unified switched capacitor compensators. The benefits of improved power quality are also covered.
This document discusses power quality monitoring. It defines power quality as the properties of the power supply delivered to users. Power quality can be affected by various steady state variations and events that cause deviations from the ideal voltage waveform. The document describes different types of power quality disturbances and how automatic classifiers are used to classify disturbances. It discusses power quality monitoring objectives and the types of commercially available power quality monitors used to identify and analyze power quality problems.
Power quality issues can cause equipment failures and financial losses for businesses. Common power quality disturbances include transients, sags, swells, and harmonics. Proper power quality monitoring using portable or permanently installed devices can help identify issues, their causes, and reduce downtime.
The document discusses power frequency disturbances, which are slower and longer lasting than electrical transients. Common power frequency disturbances include voltage sags caused by starting large loads like motors or arc furnaces, utility faults, and generator or load switching operations. Devices experience effects ranging from light flickering to equipment damage depending on the disturbance characteristics and equipment age. The document outlines various techniques to mitigate low frequency disturbances, such as isolation transformers, voltage regulators, uninterruptible power supply systems, and maintaining voltage levels within equipment tolerance criteria.
Power quality issues can arise from reactive power demand, harmonic distortion, voltage sags and swells, unbalance, flicker, notching, and interruptions. Non-linear loads like rectifiers and adjustable speed drives generate harmonics. Harmonics can overheat equipment and increase losses. Voltage sags are brief reductions in voltage from events like motor starts. Unbalance occurs when three-phase voltages differ in magnitude. Flicker is the perception of lighting variations below 25 Hz. Mitigation methods include active and passive filters, dynamic voltage restorers, static compensators, and surge arresters.
This document provides an introduction to power quality, including definitions, concepts, and classifications of various power quality disturbances. It defines power quality as the characteristics of voltage and current in a power system that allow equipment to function properly. Power quality issues are deviations from the ideal voltage and current sine waves, including transients, sags, swells, interruptions, harmonics, and voltage imbalance. These issues are characterized and classified based on duration, magnitude, frequency content, and causes. International standards for measuring and monitoring power quality are also mentioned.
The document discusses how power quality and electrical loads have changed over time, moving from mostly linear loads to mostly non-linear loads after 1980. Non-linear loads like computers produce harmonics which can overload equipment and waste energy. Upgrading to energy efficient harmonic mitigating transformers can provide significant energy savings over standard transformers by reducing losses from harmonics. Implementing a transformer upgrade program involves identifying existing equipment, quantifying savings opportunities, and showing the cost savings over the life of the new transformers.
seminar report on power quality monitoring khemraj298
The document discusses power quality monitoring and its importance for sustainable energy systems like solar power in India. It provides context on increased sensitivity of modern equipment to power quality issues and defines different types of steady state variations and events that impact power quality. Monitoring objectives include proactive and reactive approaches to characterize system performance and identify specific problems. The development of an intelligent power quality monitoring system using LabVIEW and sensors is described to efficiently monitor power quality in sustainable energy systems.
This document discusses power quality and defines it as the ability of a power system to supply voltage continuously within tolerances. It outlines various power quality events like sags, swells, interruptions, harmonics, and their causes and effects. It then describes various techniques to mitigate power quality issues, including dynamic voltage restorers, harmonic filters, static VAR compensators, and unified power quality conditioners. Maintaining high power quality improves system efficiency and equipment lifespan while eliminating problems like voltage fluctuations, harmonics, and reactive power issues.
POWER QUALITY ISSUES (POWER SYSTEM AND POWER ELECTRONICS)Rohit vijay
This document discusses power quality issues, specifically voltage sags. It defines voltage sags as decreases in voltage between 10-90% of nominal voltage lasting from half a cycle to one minute. Common causes of voltage sags include motor starting, faults in the power system, and sudden increases in load. The document discusses various methods for mitigating voltage sags, including power conditioning equipment like static VAR compensators, UPS systems, and custom devices like dynamic voltage regulators and D-STATCOMs. It also describes using an auto-transformer controlled by an IGBT switch as a method for mitigating voltage sags.
Power quality harmonics and accuracy april 2013Hyteps B.V.
This document discusses power quality, harmonics, and accuracy standards. It provides an agenda that covers definitions of power quality, improving power quality through solutions like power factor correction, power quality in SATEC products which provide detailed analysis and event logging, and accuracy standards for measurements. Key points covered include definitions of parameters like harmonics, interruptions, and voltage variations, international standards for limits like IEEE 1159 and EN50160, and how meter and CT accuracy classes are determined based on testing to standards like IEC 62053 and 62044.
This document discusses power quality issues such as voltage sags, interruptions, spikes, swells, and harmonics. It explains the causes and consequences of each issue. Solutions discussed include improving the electric grid, using distributed energy resources like generators and energy storage, following standards, installing enhanced interface devices, and making equipment less sensitive. The key is preventing power quality problems through various measures to avoid losses.
The peer-reviewed International Journal of Engineering Inventions (IJEI) is started with a mission to encourage contribution to research in Science and Technology. Encourage and motivate researchers in challenging areas of Sciences and Technology.
International Journal of Computational Engineering Research (IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
sachu technologies team provides comprehensive power quality analysis and can implement measures to bring power quality to acceptable standards. Improving power quality can bring significant financial benefits.
Poor power quality can damage sensitive equipment.
Poor power quality can lower productivity and also drive up energy costs.
Poor power quality can cause increased expenditure on electrical assets when plant or building expansion is necessary.
Poor power quality can impair the safety of electrical installations.
Design and Simulation of Generation of High DC Voltage using Cockcroft Walton...IRJET Journal
This document describes the design and simulation of a high voltage DC power supply using a Cockcroft-Walton voltage multiplier circuit. A 6-stage voltage multiplier circuit is simulated in MATLAB to generate 2kV DC output from a 230V AC input. The effects of changing load capacitance and wave shaping resistor values on the output impulse voltage are analyzed. Simulation results show the output voltage waveform matches the expected 2kV level. In conclusion, the MATLAB model demonstrates the ability of a Cockcroft-Walton circuit to effectively generate high DC voltages through voltage multiplication from a lower AC input.
Come join the area's leading power quality experts as we demonstrate and replicate common power quality issues, problems and solutions in today's industrial and commercial electrical environments.
Power quality refers to maintaining a steady supply of electric power that operates equipment properly without damage or stress. Deviations from the normal voltage can cause issues like brief power interruptions or dimming lights. Poor power quality costs US companies billions annually and negatively impacts energy efficiency. Common power quality issues include voltage variations, frequency variations, harmonic distortions, and low power factor, all of which increase energy consumption and equipment wear.
Power Quality Basics_Complex Compatibility_AclaraAclara
Power Quality is a major concern to utility customers and the utility. For the energy consumer, the economic impact of power disturbances can range from hundreds of dollars in equipment repair to millions of dollars in production losses and downtime. For utilities, disturbances lead to customer dissatisfaction and losses in load and revenue.
This presentation clarifies the unique electrical relationship between utility and customers relative to Power Quality. Introducing Power Quality terminology, tools to determine compatibility, and data that is available for analysis.
This document discusses power quality and methods to enhance it. It defines power quality and common power quality problems such as voltage sags, swells, transients, and harmonic distortion. It then describes several methods to solve power quality problems, including using hybrid filters, transformer methods, coil clocks, power factor correction, and unified switched capacitor compensators. The benefits of improved power quality are also covered.
This document discusses power quality monitoring. It defines power quality as the properties of the power supply delivered to users. Power quality can be affected by various steady state variations and events that cause deviations from the ideal voltage waveform. The document describes different types of power quality disturbances and how automatic classifiers are used to classify disturbances. It discusses power quality monitoring objectives and the types of commercially available power quality monitors used to identify and analyze power quality problems.
Power quality issues can cause equipment failures and financial losses for businesses. Common power quality disturbances include transients, sags, swells, and harmonics. Proper power quality monitoring using portable or permanently installed devices can help identify issues, their causes, and reduce downtime.
The document discusses power frequency disturbances, which are slower and longer lasting than electrical transients. Common power frequency disturbances include voltage sags caused by starting large loads like motors or arc furnaces, utility faults, and generator or load switching operations. Devices experience effects ranging from light flickering to equipment damage depending on the disturbance characteristics and equipment age. The document outlines various techniques to mitigate low frequency disturbances, such as isolation transformers, voltage regulators, uninterruptible power supply systems, and maintaining voltage levels within equipment tolerance criteria.
Power quality issues can arise from reactive power demand, harmonic distortion, voltage sags and swells, unbalance, flicker, notching, and interruptions. Non-linear loads like rectifiers and adjustable speed drives generate harmonics. Harmonics can overheat equipment and increase losses. Voltage sags are brief reductions in voltage from events like motor starts. Unbalance occurs when three-phase voltages differ in magnitude. Flicker is the perception of lighting variations below 25 Hz. Mitigation methods include active and passive filters, dynamic voltage restorers, static compensators, and surge arresters.
This document provides an introduction to power quality, including definitions, concepts, and classifications of various power quality disturbances. It defines power quality as the characteristics of voltage and current in a power system that allow equipment to function properly. Power quality issues are deviations from the ideal voltage and current sine waves, including transients, sags, swells, interruptions, harmonics, and voltage imbalance. These issues are characterized and classified based on duration, magnitude, frequency content, and causes. International standards for measuring and monitoring power quality are also mentioned.
The document discusses how power quality and electrical loads have changed over time, moving from mostly linear loads to mostly non-linear loads after 1980. Non-linear loads like computers produce harmonics which can overload equipment and waste energy. Upgrading to energy efficient harmonic mitigating transformers can provide significant energy savings over standard transformers by reducing losses from harmonics. Implementing a transformer upgrade program involves identifying existing equipment, quantifying savings opportunities, and showing the cost savings over the life of the new transformers.
seminar report on power quality monitoring khemraj298
The document discusses power quality monitoring and its importance for sustainable energy systems like solar power in India. It provides context on increased sensitivity of modern equipment to power quality issues and defines different types of steady state variations and events that impact power quality. Monitoring objectives include proactive and reactive approaches to characterize system performance and identify specific problems. The development of an intelligent power quality monitoring system using LabVIEW and sensors is described to efficiently monitor power quality in sustainable energy systems.
This document discusses power quality and defines it as the ability of a power system to supply voltage continuously within tolerances. It outlines various power quality events like sags, swells, interruptions, harmonics, and their causes and effects. It then describes various techniques to mitigate power quality issues, including dynamic voltage restorers, harmonic filters, static VAR compensators, and unified power quality conditioners. Maintaining high power quality improves system efficiency and equipment lifespan while eliminating problems like voltage fluctuations, harmonics, and reactive power issues.
POWER QUALITY ISSUES (POWER SYSTEM AND POWER ELECTRONICS)Rohit vijay
This document discusses power quality issues, specifically voltage sags. It defines voltage sags as decreases in voltage between 10-90% of nominal voltage lasting from half a cycle to one minute. Common causes of voltage sags include motor starting, faults in the power system, and sudden increases in load. The document discusses various methods for mitigating voltage sags, including power conditioning equipment like static VAR compensators, UPS systems, and custom devices like dynamic voltage regulators and D-STATCOMs. It also describes using an auto-transformer controlled by an IGBT switch as a method for mitigating voltage sags.
Power quality harmonics and accuracy april 2013Hyteps B.V.
This document discusses power quality, harmonics, and accuracy standards. It provides an agenda that covers definitions of power quality, improving power quality through solutions like power factor correction, power quality in SATEC products which provide detailed analysis and event logging, and accuracy standards for measurements. Key points covered include definitions of parameters like harmonics, interruptions, and voltage variations, international standards for limits like IEEE 1159 and EN50160, and how meter and CT accuracy classes are determined based on testing to standards like IEC 62053 and 62044.
This document discusses power quality issues such as voltage sags, interruptions, spikes, swells, and harmonics. It explains the causes and consequences of each issue. Solutions discussed include improving the electric grid, using distributed energy resources like generators and energy storage, following standards, installing enhanced interface devices, and making equipment less sensitive. The key is preventing power quality problems through various measures to avoid losses.
The peer-reviewed International Journal of Engineering Inventions (IJEI) is started with a mission to encourage contribution to research in Science and Technology. Encourage and motivate researchers in challenging areas of Sciences and Technology.
International Journal of Computational Engineering Research (IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
The document discusses power quality issues related to solar cells and inverters. It provides information on standards for power quality parameters like harmonics, voltage variations, sags and swells. The document outlines the operation of solar cells and photovoltaic cells, and discusses factors that affect their efficiency. It also summarizes Indian manufacturing guidelines for solar cells and describes different types of inverters used in photovoltaic systems.
This document discusses power quality issues related to wind power integration. It begins with an abstract noting how increasing electricity demand is leading to more renewable energy sources like wind power, but wind farm integration can negatively impact the grid's power quality. The document then covers international power quality standards, defines power quality issues, and lists various causes of power quality problems like power imbalances, voltage variations, harmonics, and flickers that can result from wind power integration. Finally, it discusses challenges wind power poses to grid stability and provides mitigation strategies like improved energy storage, forecasting, and grid reinforcement.
This document discusses power quality issues related to wind power integration. It begins with an abstract noting how increasing electricity demand is leading to more renewable energy sources like wind power, but wind integration can negatively impact the grid's power quality. The document then covers international power quality standards, defines power quality, and lists various power quality issues caused by wind power like power imbalances, voltage variations, harmonics, and flickers. Challenges of wind power integration to power system stability are also discussed. Finally, the document presents some mitigation strategies for integrating wind energy conversion systems onto the grid.
This document discusses power quality and issues that can arise such as voltage variations, frequency variations, and waveform distortions. It defines key power quality terms like sags, swells, flicker, harmonics, and describes how loads and generation sources can impact power quality. Active power filters are presented as a solution to power quality problems in electric rail systems by compensating for unbalance, harmonic distortion, and low power factor. Compression algorithms are also discussed to efficiently store and analyze large power quality data sets.
Power quality refers to maintaining a steady supply of electric power that operates equipment properly without damage or stress. Issues like voltage fluctuations, frequency variations, harmonic distortions, and low power factor can reduce efficiency and increase energy consumption and equipment damage. Common causes of power quality issues are weather events, falling trees, vehicle accidents, and construction accidents disturbing overhead power lines.
A Review on Basic Concepts and Important Standards of Power Quality in Power ...Editor IJCATR
This paper deals with the basic of Power quality in power system. In addition basic definition and important concepts was discussed in simple way. This paper also covers the important power quality standards. In addition IEEE, IEC, SEMI and UIE Power quality standards are listed. This paper would be helpful for the UG and PG students to study about the basics of Power quality in electrical engineering.
A Review on Basic Concepts and Important Standards of Power Quality in Power ...Editor IJCATR
This paper deals with the basic of Power quality in power system. In addition basic definition and important concepts was
discussed in simple way. This paper also covers the important power quality standards. In addition IEEE, IEC, SEMI and UIE Power
quality standards are listed. This paper would be helpful for the UG and PG students to study about the basics of Power quality in
electrical engineering.
Inspection of voltage sags and voltage swells incident in power quality probl...IRJET Journal
This document reviews voltage sags and swells, which are power quality problems that can occur in distribution systems. It defines voltage sags as temporary reductions in voltage between 10-90% of nominal voltage lasting from half a cycle to a few seconds. Voltage swells are increases between 110-180% of nominal voltage lasting 0.5 cycles to 1 minute. The document finds that voltage sags account for 31% of power quality issues reported. Major causes of sags and swells are discussed, such as faults, motor starting, and capacitor switching. Custom devices like DVRs and STATCOMs are mentioned as ways to mitigate sags and swells on the distribution system.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
The document discusses harmonics and its impact on industrial consumers. It defines harmonics as distortions in voltage and current waveforms that are integer multiples of the fundamental supply frequency. The proliferation of non-linear loads like variable speed drives and UPS systems has increased harmonics levels. This poses risks as harmonics can cause overheating, equipment damage, and reduced lifetimes if not properly mitigated. The document outlines various effects of harmonics and provides examples of harmonic distortion calculations. It emphasizes the importance of controlling and monitoring harmonics given their growing impact on industrial power systems.
Power quality issues arise from any deviations from the normal sinusoidal voltage or current waveform and can negatively impact electrical equipment. Some common power quality issues include voltage sags, swells, flickers, harmonics, under/over voltages, and transients. Voltage sags are the most frequent issue and can be caused by faults, overloads, or motor starts on the distribution system. Harmonics are distortions in the AC waveform caused by non-linear loads. International standards define terms and limits for ensuring acceptable power quality.
1. The document discusses the operation and maintenance of electrical systems in thermal power stations, including generators, transformers, motors, and distribution systems.
2. It covers topics such as AC and DC systems, single and three-phase systems, delta and star connections, grounded and ungrounded systems, and losses in electrical machines like hysteresis and eddy current losses.
3. The document also discusses components like transmission lines, substations, and the arrangement of electrical systems in thermal power stations.
This document provides an overview of electrical basics and classic control systems. It includes 10 chapters that cover topics such as electrical circuits, direct and alternating current, control components, motor nameplates, types of AC motors, and motor control circuits. Chapter 1 discusses basic electrical concepts including circuits, voltage sources, current, and power. Chapter 2 examines different types of control systems including classic and modern control. Chapter 3 focuses on classic control components for power and control circuits.
Transients can cause slow degradation, erratic operation, or catastrophic failure in electrical parts, insulation dielectrics, and electrical contacts used in switches and relays. The possible occurrence of transients must be considered in the overall electronic design. Required circuit performance and reliability must be assured both during and after the transient
This document discusses power quality issues such as voltage sags, harmonics, transients, and facts controllers. It defines voltage sags as brief reductions in voltage lasting milliseconds caused by increases in current or system impedance. Harmonics are distortions of the normal waveform caused by non-linear loads. Transients are high magnitude disturbances under 50 milliseconds from sources like lightning or switching. FACTS controllers like SVC and UPFC use power electronics to enhance transmission system performance.
Impartiality as per ISO /IEC 17025:2017 StandardMuhammadJazib15
This document provides basic guidelines for imparitallity requirement of ISO 17025. It defines in detial how it is met and wiudhwdih jdhsjdhwudjwkdbjwkdddddddddddkkkkkkkkkkkkkkkkkkkkkkkwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwioiiiiiiiiiiiii uwwwwwwwwwwwwwwwwhe wiqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq gbbbbbbbbbbbbb owdjjjjjjjjjjjjjjjjjjjj widhi owqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq uwdhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhwqiiiiiiiiiiiiiiiiiiiiiiiiiiiiw0pooooojjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj whhhhhhhhhhh wheeeeeeee wihieiiiiii wihe
e qqqqqqqqqqeuwiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiqw dddddddddd cccccccccccccccv s w c r
cdf cb bicbsad ishd d qwkbdwiur e wetwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww w
dddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffw
uuuuhhhhhhhhhhhhhhhhhhhhhhhhe qiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii iqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc ccccccccccccccccccccccccccccccccccc bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbu uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuum
m
m mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm m i
g i dijsd sjdnsjd ndjajsdnnsa adjdnawddddddddddddd uw
Prediction of Electrical Energy Efficiency Using Information on Consumer's Ac...PriyankaKilaniya
Energy efficiency has been important since the latter part of the last century. The main object of this survey is to determine the energy efficiency knowledge among consumers. Two separate districts in Bangladesh are selected to conduct the survey on households and showrooms about the energy and seller also. The survey uses the data to find some regression equations from which it is easy to predict energy efficiency knowledge. The data is analyzed and calculated based on five important criteria. The initial target was to find some factors that help predict a person's energy efficiency knowledge. From the survey, it is found that the energy efficiency awareness among the people of our country is very low. Relationships between household energy use behaviors are estimated using a unique dataset of about 40 households and 20 showrooms in Bangladesh's Chapainawabganj and Bagerhat districts. Knowledge of energy consumption and energy efficiency technology options is found to be associated with household use of energy conservation practices. Household characteristics also influence household energy use behavior. Younger household cohorts are more likely to adopt energy-efficient technologies and energy conservation practices and place primary importance on energy saving for environmental reasons. Education also influences attitudes toward energy conservation in Bangladesh. Low-education households indicate they primarily save electricity for the environment while high-education households indicate they are motivated by environmental concerns.
Null Bangalore | Pentesters Approach to AWS IAMDivyanshu
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
- An overly permissive IAM role configuration can lead to privilege escalation by creating a role with administrative privileges and allow a user to assume this role.
- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
- Create role with administrative privileges.
- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
Digital Twins Computer Networking Paper Presentation.pptxaryanpankaj78
A Digital Twin in computer networking is a virtual representation of a physical network, used to simulate, analyze, and optimize network performance and reliability. It leverages real-time data to enhance network management, predict issues, and improve decision-making processes.
Levelised Cost of Hydrogen (LCOH) Calculator ManualMassimo Talia
The aim of this manual is to explain the
methodology behind the Levelized Cost of
Hydrogen (LCOH) calculator. Moreover, this
manual also demonstrates how the calculator
can be used for estimating the expenses associated with hydrogen production in Europe
using low-temperature electrolysis considering different sources of electricity
Tools & Techniques for Commissioning and Maintaining PV Systems W-Animations ...Transcat
Join us for this solutions-based webinar on the tools and techniques for commissioning and maintaining PV Systems. In this session, we'll review the process of building and maintaining a solar array, starting with installation and commissioning, then reviewing operations and maintenance of the system. This course will review insulation resistance testing, I-V curve testing, earth-bond continuity, ground resistance testing, performance tests, visual inspections, ground and arc fault testing procedures, and power quality analysis.
Fluke Solar Application Specialist Will White is presenting on this engaging topic:
Will has worked in the renewable energy industry since 2005, first as an installer for a small east coast solar integrator before adding sales, design, and project management to his skillset. In 2022, Will joined Fluke as a solar application specialist, where he supports their renewable energy testing equipment like IV-curve tracers, electrical meters, and thermal imaging cameras. Experienced in wind power, solar thermal, energy storage, and all scales of PV, Will has primarily focused on residential and small commercial systems. He is passionate about implementing high-quality, code-compliant installation techniques.
Accident detection system project report.pdfKamal Acharya
The Rapid growth of technology and infrastructure has made our lives easier. The
advent of technology has also increased the traffic hazards and the road accidents take place
frequently which causes huge loss of life and property because of the poor emergency facilities.
Many lives could have been saved if emergency service could get accident information and
reach in time. Our project will provide an optimum solution to this draw back. A piezo electric
sensor can be used as a crash or rollover detector of the vehicle during and after a crash. With
signals from a piezo electric sensor, a severe accident can be recognized. According to this
project when a vehicle meets with an accident immediately piezo electric sensor will detect the
signal or if a car rolls over. Then with the help of GSM module and GPS module, the location
will be sent to the emergency contact. Then after conforming the location necessary action will
be taken. If the person meets with a small accident or if there is no serious threat to anyone’s
life, then the alert message can be terminated by the driver by a switch provided in order to
avoid wasting the valuable time of the medical rescue team.
Applications of artificial Intelligence in Mechanical Engineering.pdfAtif Razi
Historically, mechanical engineering has relied heavily on human expertise and empirical methods to solve complex problems. With the introduction of computer-aided design (CAD) and finite element analysis (FEA), the field took its first steps towards digitization. These tools allowed engineers to simulate and analyze mechanical systems with greater accuracy and efficiency. However, the sheer volume of data generated by modern engineering systems and the increasing complexity of these systems have necessitated more advanced analytical tools, paving the way for AI.
AI offers the capability to process vast amounts of data, identify patterns, and make predictions with a level of speed and accuracy unattainable by traditional methods. This has profound implications for mechanical engineering, enabling more efficient design processes, predictive maintenance strategies, and optimized manufacturing operations. AI-driven tools can learn from historical data, adapt to new information, and continuously improve their performance, making them invaluable in tackling the multifaceted challenges of modern mechanical engineering.
1. Case Studies of
Power Quality Surveys
using
Model 3196 Power Quality Analyzer
HIOKI E.E. CORPORATION
July 2005
Rev. 5
2. TABLE OF CONTENTS
Power Quality Basics: Current Power Supply Environment Page 1
Power Quality Standards Page 1
Main Power Quality Parameters Page 2 to 4
Case Study 1: Inrush Current and Current RMS Value of a Dryer Page 5 to 6
Case Study 2:
Switching of Power Factor Improvement
Capacitor
Page 7 to 8
Case Study 3:
Voltage Dip (Instantaneous Voltage Drop
- at Receptacle
Page 9 to 10
Case Study 4:
Voltage Dip (Instantaneous Voltage Drop)
- at Distribution Panel
Page 11
Case Study 5:
Transient Overvoltage
Page 12 to 13
Case Study 6:
Periodical Instantaneous Voltage Drop
Page 14
Case Study 7:
General UPS Switching Waveform
Page 15
Case Study 8: Page 16
Case Study 9: Page 17
Case Study 10: Voltage Waveform Noise & UPS Switching Page 18 to 19
Appendix: Power Quality Survey Procedures Page 27 to 28
Case Study 11:
Case Study 12:
Voltage Dip in a Factory
Inflow and Outflow of Harmonics
Voltage Drop Caused by Wiring Impedance
Transients Caused by Glow Fluorescent Lighting
Page 20 to 22
Page 23 to 26
3. - page 1 -
Power Quality Basics
Current Power Supply Environment
Power Quality Standards
Various factors can contribute to worsening power quality
International
Power Quality
Deterioration
Open market
Tough competition to
cut costs
Increase use of PCs
and inverter devices
Connection with new
energy sources (wind,
solar, gas turbine, etc.)
Connection with on-
site power supply
Connection
mixes the
different
power
characteristics
Europe
U.S.A.
Standard Title Published Comment
IEC
61000-4-7
IEC
61000-4-15
IEC
61000-4-30
EN50160
IEEE 1159
IEEE 519
IEEE 446
ANSI C84.1
General guide on harmonics and inter-
harmonics measurements and
instrumentation, for power supply systems
and equipment connected thereto
1991
2002 revised
Actualization of inter-
harmonic concept (from
revision)
Flicker meter - Functional and design
specifications
Testing and measurement techniques
Power Quality measurement methods
1997
2003 A1
2003
120V/60Hz added in
amendment
New standard
Standard Title Published Comment
Standard Title Published Comment
Voltage Characteristics of electricity
supplied by public distribution systems
1995,
1999 revised
General power quality
standard
IEEE Recommended Practice for
Monitoring Electric Power Quality
IEEE Recommended Practice and
Requirements
IEEE Recommended Practice for
Emergency and Standby Power Systems
for Industrial and Commercial Applications
Electrical Power Systems and Equipment -
Voltage Ratings (60Hz)
1995
1992
1995
1995
Anomaly voltage
Classification of basic
terms
Standards for harmonic
limit values
Describes the CBEMA
curve
Voltage limit values
4. - page 2 -
ITIC (CBEMA) curve
The ITIC curve judges the allowable level of
voltage RMS fluctuation from the voltage swell,
voltage dip and interruption events.
The analysis is made by the period and depth of
each event according to the limit value of the ITIC
curve.
The ITIC (Information Technology Industry
Council) curve is the most recent version of the
older CBEMA (Computer and Business
Equipment Manufacturers Association) curve.
Both were created by CBEMA. The original
CBEMA curve was widely used in the U.S.A.
Main Power Quality Parameters
1. Transient overvoltage (impulse)
1) Phenomenon
Radical changes in voltage with high voltage
peaks
2) Cause
3) Damage
4) Analysis
Lightning strikes
Power circuit switching
Closure of inductive circuits
Arc to the ground
Load switching
Contact of a bouncing relay
Destruction of power supplies of
equipment
Equipment reset
Waveform (Maximum voltage level, Rise
time, Phase angle, Fluctuation,
Repeatability)
The faster rise time means a closer
occurring point.
2. Voltage Dip
1) Phenomenon
Instantaneous drop of RMS voltage
2) Cause
3) Damage
Large inrush current by turning on heavy
loads
Accident in the distribution network
(Lightning, snow, ice, contact of birds/
trees, effects of accidents)
Short-circuit
Stop or equipment reset
5. - page 3 -
3. Voltage Swell
1) Phenomenon
Instantaneous rise of RMS voltage
2) Cause
3) Damage
Lightning strikes
Introducing heavy loads
Destruction of power supplies in
equipment
4. Instantaneous Interruptions
1) Phenomenon
Instantaneous or short/long term power
outage
2) Cause
3) Damage
Accident on distribution network
(Lightning, snow, ice, contact of birds/
trees, effects of accidents)
Short-circuit
Stop or equipment reset
5. Unbalance Factor
1) Phenomenon
Imbalance of each phase in 3-phase system
2) Cause
3) Damage
Imbalance of loads by 1-phase load
connection (especially long distribution
lines)
Transformer capacity difference at
receptacle
Overheating of a 3-phase inductive motor
or transformer
Stop equipment by 3E relay tripping (over-
current, missing phase, reverse-phase)
Uneven motor rotation
6. 6. Harmonics
1) Phenomenon
Voltage or current waveform distortion
2) Cause
3) Damage
Thyristor powered conversion devices
Inverter, Variable frequency drives
Overheating, burning, abnormal sounds or
vibration sound caused by the inflow of
harmonic current to the equipment
Malfunctions due to the harmonics voltage
(overheating or burning of reactor for
phase advancing capacitor)
7. Flicker
1) Phenomenon
Regularly repeated voltage impulses spanning
one or more cycles which cause flicker in the
lighting device
2) Cause
3) Damage
Arc/blast furnaces
Arc welding
Flicker in the lighting device
Equipment malfunction
- page 4 -
7. - page 5 -
CASE STUDY 1
Inrush Current and Current RMS Value of an Industrial Dryer
Environment:
Problem:
Analysis:
Target: 1-phase 2-wire, 100V circuit
This is a simple simulation example.
By using an industrial dryer (100V
AC, 1kW, 50/60Hz), the RMS
fluctuation and inrush currentare
measured while switching the dryer
from "OFF=>ON=>COLD=>OFF."
Note:
Model 9694 Clamp on Sensor is
clamped to the 10-turn coil with a CT
setting 0.1.
To record the inrush current event waveform, use thecurrent peak event.
To record the waveform while the dryer is continuously operating in HOT, using themanual event
([ESC]+[EVENT]) is effective.
Current RMS Value Fluctuation
OFF HOT HOTCOLD
The current value while a dryer is working is
10Arms, but the start-up current rises to
10.951Arms.
8. - page 6 -
Fluctuation of Current Waveform Peak (+) Fluctuation of Current Waveform Peak (-)
Fluctuation of Voltage RMS Value Fluctuation of Active Power RMS Value
A voltage drop of about 4Vrms is measured when the dryer is in operation.
The maximum power is 1.1071kW
Inrush Current Waveform
9. - page 7 -
CASE STUDY 2
Voltage Drop Caused by Wiring Impedance
Environment:
Problem:
Analysis:
Target: 1-phase 2-wire, 100V circuit
This is an easy simlulation similar to Case Study 1 to monitor the voltage drop caused by wiring
impedance. The voltage at a load shows the voltage drop to the supply side when the wire is thin
and long.
CH2
CH1
When switching an industrial dryer (100V
AC, 1kW, 50/60Hz) from OFF to HOT to
COLD and back to OFF, confirm the
difference in voltage drop between short
and long wirings.
1) When wiring is short
(low wiring impedance without the wires
circled in red)
2) When wiring is long
(high wiring impedance with wires circled in
red)
1) Short Wiring 2) Long Wiring
Voltage RMS Value Fluctuation
Voltage at power supply side
Voltage at consumption side
U1 (CH1: red) is the voltage not affected
by the wiring impedance.
U2 (CH2: green) is the voltage affected
by the wiring impedance.
By adding high wiring impedance, the
voltage drops for 6Vrms on the
consumption side.
The wiring impedance of the wires circled in
red is 0.6-Ohm.
The voltage drop is calculated by usingthe
Ohm's Law such that "0.6-Ohm x 10A =
6Vrms."
6Vrms
10. - page 8 -
1) Short Wiring 2) Long Wiring
Current RMS Value Fluctuation
1) Short Wiring 2) Long Wiring
Current Peak Value Fluctuation
In this dryer example, the current consumption at a load is slightly reduced when the wirng is long.
The dryer is a resistive load, so that the current consumption, which means the power consumption,
is reduced by the voltage drop.
If a constant power controlled load is connected, the power consumption is stable despitethe
voltage drop. Therefore, the current consumption increases.
When HOT
When HOT
When HOT
When HOT
11. Transient peak value is accurately
measured using the 2MHz sampling
speed.
- page 9 -
CASE STUDY 3
Transients Caused by GlowFluorescent Lighting
Environment:
Problem:
Analysis:
Target: 1-phase 2-wire, 100V circuit
This is an example of measuring transient overvoltage when turning on glow fluorescent lighting.
A glow fluorescent light incorporates a glow
lamp and is widely recognized as a low-cost
alternative to fluorescent lighting.
A fluorescent light needs to be warmed-up for
its electrodes to be switched on. A glow lamp
is provided for this purpose. It flashes to
warm-up the electrodes before the fluorescent
light is actually turned on.
Transient overvoltage is generated at the first
flash of a glow lamp, which affects electronic
equipment located nearby.
Glow lamp
Voltage and Transient Waveforms When Turning On the Fluorescent Light
Line of voltage=0
Cursor B
Cursor A
12. - page 10 -
The power is turned on at the voltage
waveform peak (128.9V) and the generated
transient overvoltage is 103.1V in the negative
direction.
Voltage and Current Waveforms When Turning On the FluorescentLight
When transient overvoltage occurs, a high
current flows instantaneously.
This example is measured by using a 10-turn
coil without a CT ratio setting.
The screen shot on the left shows that
0.9602A of current flowed instantaneously to
the negative direction.
13. - page 11 -
CASE STUDY 4
Switching of Power Factor Correction Capacitor
Environment:
Problem:
Analysis:
Target: 1-phase 2-wire, 100V circuit
The power supply of equipment is damaged.
Some events are recorded by measurement.
The switching waveform, which occurs during the power factor correction capacitor switching, is
detected. This kind of voltage waveform is recorded when the power factor correction capacitor is
installed in a facility. The switching noise comes through the low-voltage circuit without a filtering
device.
Voltage Noise Waveform 1 (By the voltage waveform distortion event)
Also, a transient (impulse) voltage waveform is detected.
This kind of waveform occurs when the voltage waveform is affected by the start-up current of
equipment.
Voltage Noise Waveform 2 (By the voltage waveform distortion event)
To detect intermittent noise,the voltage waveform distortion event is effective. The voltage
waveform distortion event is set as the percentage of the voltage range. A setting from 10%to
15% is recommended.
Note:
14. - page 12 -
CASE STUDY 5
Voltage Dip (Instantaneous Voltage Drop) - at Receptacle
Environment:
Problem and Analysis:
Target: HIOKI headquarters building,
3-phase 4-wire, 6.6kV receptacle, Secondary side of PT
While measuring for 1 year at the receptacle of a 3-phase 6.6kV circuit, a voltage dip is detected
only during a lightning strike. This voltage dip occurred 6 times in 3 consecutive days (August5 to
7, 2003). The residual voltage is very low and a long period is detected on CH3 (T-R phase) as
4.708kV for 109ms.
1 year from June 2003 to May2004Measured period:
Voltage Fluctuation
Classification in EN50160 mode
(Simultaneous events on 3 phases are counted asone.)
Voltage Dip Evaluation by ITIC Curve
(plotted for each phase separately)
15. - page 13 -
Event Voltage Fluctuation of the Lowest Residual Voltage and the Shortest Period Voltage Dip
The instantaneous high voltage is generated by a lightning strike and it shorts the distribution
cable and tower. Then, the fault current flows and the voltage drops.
To remove this fault, the circuit breaker takes effect , but the voltage drops until that time
(approx. 0.07 to 2s).
This is the instantaneous voltage drop (voltage dip) caused by a lightning strike.
Protective
relay
Transformer
Breaker
2. Problem on distribution
3. Problem on network
4. Instantaneous voltage drop
5. Malfunction of equipment
Path of a Voltage Dip
Protective
relay
Breaker
16. - page 14 -
CASE STUDY 6
Voltage Dip (Instantaneous Voltage Drop)- at Distribution Panel
Environment:
Problem and Analysis:
Target: HIOKI headquarters building, East side, 5th floor
3-phase 3-wire, 200V distribution panel
4 voltage dips caused by lightning were detected during measurement(different period than Case
Study 3). The distribution panel (1-phase 3-wire) was affected by the voltage dip that occurred at
the high voltage distribution network. The table below shows the residual voltage and period of
each voltage dip. Voltage dips caused by lightning are unpreventable by the power distribution
companies. Therefore, users should take appropriate countermeasures such as connectinga UPS
to their PCs.
From June 9, 2002 to August 9, 2002Measured period:
Residual Voltage Period
1st voltage dip
2nd voltage dip
3rd voltage dip
4th voltage dip
63Vrms
47Vrms
82Vrms
56Vrms
117ms
109ms
50ms
116ms
Event Voltage Fluctuation at the 2nd VoltageDip
Voltage and Current Waveforms at the 2nd VoltageDip
17. - page 15 -
CASE STUDY 7
Transient Overvoltage
Environment:
Analysis:
Target: Factory, 3-phase 3-wire, 200V circuit
A transient overvoltage was detected in all events occurring several times duringthe
measurement. Unfortunately, the cause of the transient could not be determined.
Problem:
The screen of equipment does not correctly display.
Analysis of transient waveform
Occurred on all 3 phases (R-S, S-T, T-R) simultaneously.1)
Occurred twice in 1 cycle of the commercial waveform, and the interval between 2 events is
820µs.
2)
The level is between 120V to 260V peak-to-peak.3)
The frequency is between 10kHz and 30kHz.4)
The threshold set at 1/2 of the waveform peak value is effective for the transient overvoltage.
For example, set the threshold at 0.07kV for the 100Vrms circuit, and 0.14kV for the 200Vrms circuit.
Note:
Analysis of Transient Overvoltage
U1 U2 U3
Max. value
Min. value
Transient
p-p value
-116.0V
-329.3V
323.4V
153.5V
98.4V
-55.1V
213.3V 169.9V 153.5V
18. - page 16 -
CASE STUDY 8
Periodical Instantaneous Voltage Drop
Environment:
Analysis:
Target: Retail store, 1-phase 2-wire, 100V outlet
When analyzing the voltage RMS value fluctuation, the following two phenomena were observed.
(The graph shows measurement during 12 hours in the night for a period of 2 weeks.)
Problem:
No apparent trouble is detected, but the voltage fluctuation is big.
Maximum value: 106.70Vrms, Average value: 102.53Vrms, Minimum value: 93.25Vrms1)
Instantaneous voltage drop occurred every 13 minutes.2)
Voltage Fluctuation
The cause of the instantaneous voltage drop every 13 minutes is assumed to originate froman
electronic device connected to the line as this outlet is turned on or works periodically via a timer.
The device may have a high inrush current - common in equipment such as laser printers, copy
machines, electric heaters, etc. A laser printer consumes current periodically, and causes a
voltage drop as a result of its start-up current consumption. An electric heater also causes a
voltage drop from the periodic inrush current ON/OFF of the thermostat,
There are many instantaneous voltage drops, but the minimum voltage is 93.25Vrms which is
about 7% lower than the nominal voltage. Most equipment works normally at this voltage level.
19. - page 17 -
CASE STUDY 9
General UPS Switching Waveform
Environment:
Problem and Analysis:
Most low cost UPS used for general purposes output a square wave. However, mostpeople
assume that a sine wave is output. Here is a sample waveform output by the UPS.
UPS for a desktop PCs sold in retail stores (1-phase 2-wire, 100V)
Low cost inverter (variable frequency drive) type1)
Commercial purpose without a compensation function for the voltage distortion,etc.2)
Note that the voltage swell or dip occurs in switching if the UPS does not compensate for the
period.
Event Voltage Fluctuation of UPS Output
Switching from
commercial
power supply to
UPS when the
power supply
drops.
Switching from
UPS to
commercial
power supply
when the power
supply recovers.
Voltage Waveform when the Power Supply Drops
(switching from commercial power supply to UPS)
Voltage Waveform when the Power Supply Recovers
(switching from UPS to commercial power supply)
Target:
20. - page 18 -
CASE STUDY 10
Voltage Waveform Noise & UPS Switching
Environment:
Analysis:
Target: 1-phase 2-wire, 100V power supply circuit
68 "Wave (voltage waveform distortion)" events were recorded during an 18-day measurement
period using the following settings on Model 3196. All events are of the same type.
Problem:
Malfunction of equipment
Event Settings of Model 3196
Event List
21. - page 19 -
Next, the waveform of each "wave" event was checked, and 2 types of events were found.
We can assume that the events "switched to a sine wave after the waveform noise" were due to the
switching to the UPS output (stand-by system).
Not switched to a sine wave after the waveform noiseNo.1:
Switched to a sine wave after the waveform noiseNo.2:
It appears that waveform No.1 has a higher noise level and should be switched to the UPS output.
However, waveform No.2 shows a bigger difference in the current waveform when the voltage
waveform shows the noise. Therefore, we can assume that a transient overvoltage occurs
simultaneously when this event occurs. Unfortunately, the transient overvoltage is not detected,
because its threshold is set at 0.480kV (480V).
We propose setting the threshold at 1/2 of the waveform peak (70V= 0.0718kV for 100V circuit)
No.1: Not Switched to the Sine Wave after the Waveform Noise
No.2 Switched to the Sine Wave after the Waveform Noise
Switched to the sine wave
22. - page 20 -
CASE STUDY 11
Voltage Dip in a Factory
Environment:
Analysis:
Target: A factory in Southeast Asia, 1-phase 2-wire, 100V circuit
Problem:
Power supply is damaged.
Voltage fluctuation1.
The following power characteristics were concluded from this 2 week voltage fluctuation graph.
Voltage Fluctuation
No.1
No.2
No.3
Unfortunately, sufficient event data was not recorded in No.1 and No.2. , so thatdetailed
analysis was not possible. The important point to note is that a large voltage fluctuation
occurred between 9 p.m. and 9 a.m. everyday (No.3), and the fluctuation was about50V
(between 75Vrms and 125Vrms).
Event data2.
The voltage dip (instantaneous voltage drop) occurred frequently at night. Only 5 voltage
dips were detectable in a 1s period. The situation of voltage dip occurrence demonstrates
the same tendency.
This is the analysis of one voltage dip event.
When the depth of the voltage dip reaches 90Vrms, the power supply is switched
from the commercial supply to the UPS.
(1)
When the power supply is switched to the UPS, the voltage RMS value increasesto
116Vrms (125Vrms maximum).
(2)
The voltage waveform changes from the sine wave to the square wave in the UPS
supply.
(3)
The square wave continues for about 1.25s(4)
(5) The power supply is changed from the UPS to the commercial supply later. Upon
this switching, the voltage drops to 78Vrms (75Vrms minimum) for a short period.
1
2
3
Supply voltage
Maximum
Minimum
Average
Voltage fluctuation graph
No.1 (blue)
No.2 (green)
Voltage value
131.67Vrms
0.15Vrms
98Vrms
23. - page 21 -
Event Voltage Fluctuation at the Voltage Dip Occurrence
Voltage Waveform at the Start of the Voltage Dip
Voltage Waveform at the End of the Voltage Dip
(1)
(2)
(3)
(4)
(5)
(1)
(2) (3)
(4) (5)
24. - page 22 -
Summary of analysis3.
Worse power supply quality occurs frequently at night (9 p.m. to 9 a.m.).1)
Worse power quality phenomena starts when the voltage dips.2)
Voltage swell occurs when switching from the commercial power to the UPS due to the
voltage dip.
3)
The voltage dip occurs when the commercial power recovers and the power supply is
switched from the UPS to the commercial supply.
4)
Countermeasures4.
Primary solution1)
Alternative solution2)
Frequent switching to the UPS because of a voltage dip is not favorable. It appears
that overload current flows to the equipment due to voltage dips and swells. To
solve this problem without fail, the power supply should be stabilized to prevent the
occurrence of a voltage dip.
The UPS is used as a "stand-by power system (SPS)." By changing it to an albeit
more costly "on-line UPS system", the dips and swells can be reduced during UPS
switching.
Circuit example of
Stand-By Power
System
Circuit example of
On-Line UPS System
Circuit example of
Line-Interactive System
[#] Alternate connection to AC input is allowed.
[##] Blocking diode, cyclister or switch
Switch
AC
output
Charger
(option)
Rectifier Inverter
[##]
AC input [#]
AC input [#]
AC input [#]
Normal operation
Charged energy
operation
Bypass operation
Bipass
DC link
Rechargeable
batteries
Power
interface
[##]
Normal operation
Charged energy
operation
AC outputAC input
Rechargeable
batteries
Charger
UPS
AC
output
Bypass
Inverter
AC input [#]
AC input [#]
[#] Alternate connection to AC input is allowed.
Normal operation
Charged energy
operation
Optional connection
25. - page 23 -
CASE STUDY 12
Inflow and Outflow of Harmonics
Environment:
Analysis:
Target: 3-phase 3-wire (3P3W2M), 6.6kV circuit
This is an example of inflow and outflow judgement taken as a result of harmonics measurement
Using a 3-phase 3-wire set up, the overall inflow and outflow of a 3-phase installation are judged
by the harmonic voltage-current phase difference (θsum). When it is between -90 to 0 to +90
degrees, it is inflow. Conversely, outflow is determined when the sum is in between -180 to -90 or
+90 to +180 degrees.
The fundamental wave (brown) is consumption (inflow) as shown below.
Most of the 5th harmonic (green) is also inflow.
Time Plot of Harmonic Voltage-Current Phase Difference (fundamental and 5th harmonic)
The 3rd harmonic (red) is outflow in the graph below. The 7th (blue) harmonic is outflow.
The data shows with the vertical lines that the phase difference exceeds 180 degrees and returns
to -180 degrees (or vice versa).
Time Plot of Harmonic Voltage-Current Phase Difference (3rd and 7th harmonics)
Outflow
Outflow
Inflow
Outflow
Outflow
Inflow
26. Outflow
Outflow
Inflow
Inflow
Inflow
Inflow
Inflow
Inflow
Inflow
Inflow
Inflow
Inflow
- page 24 -
Model 9624 PQA HiVIEW and Model 9624-10 PQA HiVIEW Pro show the harmonic time plot
graph by connecting the maximum and minimum values in each interval with a horizontal line.
Therefore, a rapid change is reflected in the time plot graph.
However, the judgment of inflow and outflow is not easy to make using that time plot graph,so we
recommend converting the data to CSV format and creating a graph with "AvePhasesum"of the
relevant harmonics order only (without using "MaxPhasesum" and "MinPhasesum"), to determine
the inflow and outflow.
Example 1
-180
-90
0
90
180
Time
Phasedifference[deg.]
Example 2
Red: 3rd harmonic, Green: 5th harmonic, Blue: 7th harmonic
Date
2004/9/3
2004/9/3
2004/9/3
2004/9/3
2004/9/3
2004/9/3
2004/9/3
2004/9/3
2004/9/3
2004/9/3
2004/9/3
2004/9/3
Time
6:50:00
6:55:00
7:00:00
7:05:00
7:10:00
7:15:00
7:20:00
7:25:00
7:30:00
7:35:00
7:40:00
7:45:00
AvePhasesum (5)
Inflow /
Outflow
-93.07
-90.63
-84.20
-89.23
-87.79
-87.42
-87.16
-86.08
-79.51
-84.34
-80.74
-78.41
Calculation
=IF(ABS(C2)>90,"Outflow",
"Inflow")
27. <Reference> Guideline for the Harmonics of Distribution Network (Japan)
- page 25 -
Official Report of the Ministry of Economics and Industries in Japan:
"Guideline for Harmonics Deterrence Countermeasures on Demand-Side that receivesHigh-
Voltage or Special High-Voltage" (September 30, 1994)
* The following shows the limit values which measurement instruments can detect.
-1.
5% at 6.6kV system, 3% at special high-voltage system
-2.
Upper limit values of harmonics outflow current (mA) per 1kW Contracted Power
Order
Voltage [kV]
6.6
22
33
66
77
110
154
220
275
500
5th 7th 11th 13th 17th 19th 23rd
Higher
than
23rd
3.5
1.8
1.2
0.59
0.50
0.35
0.25
0.17
0.14
0.07
2.5
1.3
0.86
0.42
0.36
0.25
0.18
0.12
0.10
0.05
1.6
0.82
0.55
0.27
0.23
0.16
0.11
0.08
0.06
0.03
1.3
0.69
0.46
0.23
0.19
0.13
0.09
0.06
0.05
0.02
1.0
0.53
0.35
0.17
0.15
0.10
0.07
0.05
0.04
0.02
0.9
0.47
0.32
0.16
0.13
0.09
0.06
0.04
0.03
0.02
0.76
0.39
0.26
0.13
0.11
0.07
0.05
0.03
0.03
0.01
0.70
0.36
0.24
0.12
0.10
0.07
0.05
0.03
0.02
0.01
<Reference> Concept of inflow and outflow of harmonics
Fundamental
wave
Load
Harmonics
Distribution
Measuring
instrument
Measuring
through VT(PT) or
CT for high and
extra-high voltage
networks
Outflow
Inflow
Inflow
Outflow
Condition
The harmonics flow from
distribution to load
The harmonics flow from
load to distribution
Cause
Distribution side
(The harmonics generated by distribution is
bigger than the harmonics generated by load.)
Load side
(The harmonics generated by load is bigger
than the harmonics generated by distribution.)
Harmonics Voltage (Total Harmonic Voltage Distortion)
Harmonics Current
Load
Distribution
Measuring
instrument
Measuring
through VT(PT)
or CT for high
and extra-high
voltage networks
28. - page 26 -
<Reference> Harmonic Inflow/Outflow judgment on a measurement instrument
-1.
Judge the inflow/outflow by the polarity of the harmonic (effective) power. (Judge each
phase and each order independently.)
Judgment by harmonic power
-2.
Judge the inflow or outflow by the harmonic voltage-current phase difference (difference
between harmonic voltage phase angle and harmonic current phase angle).
For 3-phase 3-wire (3P3W2M or 3P3W3M) installations, we recommend using the harmonic
voltage-current phase difference of "sum" value.
Judgment by the harmonic voltage-current phase difference
Inflow
Outflow
Harmonic power is + (positive).
Harmonic power is - (negative).
Problem
The higher the order, the smaller the harmonics power level.
The smaller level makes it difficult to judge the polarity accurately, thus
making it difficult to judge inflow and outflow.
Inflow
Outflow
-90 to 0 to +90 degrees
-180 to -90 degrees, +90 to +180 degrees
Harmonic voltage-current phase angle
Problem
Judge to see if the high harmonic current level exceeds the limit. Do
not watch the harmonic current amplitude level.
Then, judge the inflow or outflow by watching the harmonic voltage-
current phase difference.
LEAD
LAG
InflowOutflow
Voltage-Current
Phase Difference
+90deg.
-90deg.
0deg.+/-180deg.
29. - page 27 -
APPENDIX
Power Quality Survey Procedures
Power quality survey procedures
Step 1:
Step 2:
Step 3:
Step 4:
Purpose
Location of problem (measurement target)
Advanced confirmation at site (collecting the site information)
Measure using a power quality analyzer
4-1.
4-2.
4-3.
4-4.
Normal condition measurement
Time plot recording for a certain period
Selecting the event parameters and thresholds
Long period measurement
Step 1: Purpose
Clearly confirm the purpose of the investigation: Purpose 1 or Purpose2?
1. Researching the condition of the power quality
There is no specific problem with the power supply, but the condition of thepower
quality at the site needs to be known.
Periodical power quality statistic research
Research before installing electric equipment
Step 2: Location of problem
Specify where the problem is occurring (identify the measurement site)
If measurement at multiple sites is possible, detecting the cause of the problem can be
easier and faster.
1. Network circuit inside a substation
(Power companies only)
2. Receptacle point (high/low voltage)
3. Transformer panel, Distribution panel
4. Power supply for electric equipment
(Outlet, etc.)
1. Frequency:
50/60Hz
2. Wiring:
1P2W/1P3W/3P3W2M/3P3W3M/3P4W
3. Neutral line measurement:
ON/OFF (CH4)
4. Nominal voltage:
100V to 600V
Points to confirm
2. Investigating the cause of a power abnormality
A quick solution needs to be found to counteract a problem with the power supply.
30. - page 28 -
Step 3: Advanced confirmation at site (collecting site information)
Collect as much site information as possible
2
3
1
Details of power
supply problem
Period of power
supply problem
Confirm the overall
site
Destruction, Damage, Malfunction
Constant, Periodic, Intermittent
Existence of other equipment having the power supply problem,
Working cycle of main electric equipment, Added or replaced
equipment in the site, Power distribution network check at the
site
Main electric equipment and power distribution network
2
1
Main electric
equipment
Power distribution
network
Large copy machines, UPS, Elevators, Air-compressors, Air-
conditioners compressors, Battery chargers, Cooling equipment,
Air-handlers, Timer controlled lighting, Transmission drive
equipment
Defect or deterioration on conduits, Overheat or noise on
transformers, Oil leakage, Overheat or loose on circuit breakers
Step 4: Measure using a power quality analyzer
Start measurement by using a power quality analyzer
2
3
1
Normal condition
measurement
Time plot recording
for a certain period
Selecting the event
parameters and
thresholds
Confirm the instantaneous value in the VIEW screen of 3196.
Voltage level, Voltage waveform, Current waveform, Voltage
waveform distortion (THD)
Record the power supply fluctuation without setting events
(15min to 1 day).
3196 settings
This can be omitted when urgent measurement is required.
Limit the number events to as few as possible at the beginning.
*Set the thresholds smaller and increase them gradually iftoo
many events are being recorded.
4
Load period
measurement
3196 settings
Power, MAX/MIN/AVE (recommended)
P&Harm, MAX/MIN/AVE (to record
harmonic fluctuation
Rec.Data:
Minimum required events
Swell: 110%
Dip: 90%
Interruption: 10%
Waveform distortion: 5% to 15%
Transient: 100V to 200V (for 100V circuit)
*
*
MemoryFull: LOOP
AutoSave: Binary