The document summarizes the results of a power quality assessment study conducted on Transformer No. 2 at the Zafarana Wind Farm in Egypt. Key findings from the study include:
1. Bus bar voltage was found to vary between 21.06 kV to 22.73 kV, within international standards of ±5% nominal voltage.
2. Total harmonic distortion of the bus bar voltage was between 0.3-3.11%, within standards of less than 5%.
3. Grid frequency was very stable between 49.86-50.13 Hz, within standards of ±1% nominal frequency.
4. Reactive power consumed by the wind turbines averaged 17.22 kV
Voltage-current Double Loop Control Strategy for Magnetically Controllable Re...Kashif Mehmood
Voltage regulation depending on reactive power
compensation is the main feature of the AC power supply
system. Magnetically controllable reactors (MCR) are
becoming a growing demand for this purpose. The structure
and working principles of MCR are analysed in this paper
while a simulation model is established. The reactive power
compensation strategy based on a single loop voltage control
system (SLVCS) is presented and a double loop
voltage-current control system (DLVCCS) is proposed. A
comprehensive scenario is developed to mitigate reactive power
compensation by using the proposed controls. Simulation
results substantiate that proposed controls of MCR has a faster
response in comparison to the traditional control, and it
provides the least voltage variation at the line end. It also
shows that the proposed control on MCR meet the desired
objective of the voltage regulation and provides flexibility to ac
transmission system
This document summarizes a research paper that proposes using a battery energy storage system (BESS) at the point of common coupling for a wind farm to provide continuous power output. It presents a methodology to determine the optimal BESS capacity needed to balance the intermittent power from the wind farm and maintain a constant output. The paper models the wind power profile, develops control algorithms for the converters, sizes the BESS based on the maximum power and energy needed over time, and simulates the system in MATLAB/Simulink. The results demonstrate that the BESS is able to smooth fluctuations and provide continuous power without disturbing the grid.
Hysteresis current controller for single phase three level vsiNitish NIT
This document presents a hysteresis current controller for single-phase three-level voltage source inverters. Conventional hysteresis current control has variable switching frequency that depends on load parameters, which makes the system complex. The proposed method modifies the hysteresis current controller to make the switching frequency independent of load by dynamically varying the hysteresis bandwidth between switching intervals based on mathematical equations. The results show this method provides constant switching frequency, low switching losses, and simple control logic implementation while maintaining benefits of hysteresis current control.
This Power Point Presentation includes Automatic Generation control :
Learning Objective: To illustrate the automatic frequency and voltage control strategies for single and two
area case and analyze the effects, knowing the necessity of generation control.
Learning Outcome:Upon successful completion of this course, the students will be able to Analyze the generation-load balance in real time operation and its effect on frequency and
develop automatic control strategies with mathematical relations.
Concept of AGC, complete block diagram representation of load-frequency control of an
isolated power system, steady state and dynamic response,
The document discusses automatic load frequency control (ALFC) in a power system. ALFC aims to maintain system frequency by matching generator output to changing load. It does this through a feedback control loop involving the speed governor, hydraulic actuator, turbine, and generator. The speed governor senses deviations in frequency and power setting to adjust the hydraulic actuator. This controls the turbine output to balance generator power with load demand and regulate frequency. The control loop maintains small, slow load changes but not large imbalances. The document analyzes the static performance of the speed governor control loop under different network conditions.
- The document compares using two types of smart loads (SLQ and SLBC) for primary frequency control on power systems with high renewable penetration.
- SLBC uses back-to-back converters to provide independent and flexible control of active and reactive power, while SLQ uses reactive compensation.
- Case studies on a 4 generator system and 39 bus New England grid show SLBC more effectively regulates frequency for both over and under-frequency events compared to SLQ.
- SLBC maintains performance for loads near unity power factor where SLQ is ineffective, and requires comparable converter ratings to SLQ for under-frequency events but much less for over-frequency events.
This document presents and compares several control schemes for a Doubly Fed Induction Generator (DFIG) under unbalanced grid voltage conditions. It describes a previously proposed Direct Power Control (DPC) method that uses Notch filters to eliminate harmonic components during voltage unbalances. It also describes a previously proposed Stator Flux Oriented Control (SFOC) method that uses Notch filters and a newly proposed SFOC method that adds a Sequence Component Controller to eliminate negative sequences. Simulations show the enhanced stability of active power, reactive power and generator torque provided by these control schemes under unbalanced voltages.
Voltage-current Double Loop Control Strategy for Magnetically Controllable Re...Kashif Mehmood
Voltage regulation depending on reactive power
compensation is the main feature of the AC power supply
system. Magnetically controllable reactors (MCR) are
becoming a growing demand for this purpose. The structure
and working principles of MCR are analysed in this paper
while a simulation model is established. The reactive power
compensation strategy based on a single loop voltage control
system (SLVCS) is presented and a double loop
voltage-current control system (DLVCCS) is proposed. A
comprehensive scenario is developed to mitigate reactive power
compensation by using the proposed controls. Simulation
results substantiate that proposed controls of MCR has a faster
response in comparison to the traditional control, and it
provides the least voltage variation at the line end. It also
shows that the proposed control on MCR meet the desired
objective of the voltage regulation and provides flexibility to ac
transmission system
This document summarizes a research paper that proposes using a battery energy storage system (BESS) at the point of common coupling for a wind farm to provide continuous power output. It presents a methodology to determine the optimal BESS capacity needed to balance the intermittent power from the wind farm and maintain a constant output. The paper models the wind power profile, develops control algorithms for the converters, sizes the BESS based on the maximum power and energy needed over time, and simulates the system in MATLAB/Simulink. The results demonstrate that the BESS is able to smooth fluctuations and provide continuous power without disturbing the grid.
Hysteresis current controller for single phase three level vsiNitish NIT
This document presents a hysteresis current controller for single-phase three-level voltage source inverters. Conventional hysteresis current control has variable switching frequency that depends on load parameters, which makes the system complex. The proposed method modifies the hysteresis current controller to make the switching frequency independent of load by dynamically varying the hysteresis bandwidth between switching intervals based on mathematical equations. The results show this method provides constant switching frequency, low switching losses, and simple control logic implementation while maintaining benefits of hysteresis current control.
This Power Point Presentation includes Automatic Generation control :
Learning Objective: To illustrate the automatic frequency and voltage control strategies for single and two
area case and analyze the effects, knowing the necessity of generation control.
Learning Outcome:Upon successful completion of this course, the students will be able to Analyze the generation-load balance in real time operation and its effect on frequency and
develop automatic control strategies with mathematical relations.
Concept of AGC, complete block diagram representation of load-frequency control of an
isolated power system, steady state and dynamic response,
The document discusses automatic load frequency control (ALFC) in a power system. ALFC aims to maintain system frequency by matching generator output to changing load. It does this through a feedback control loop involving the speed governor, hydraulic actuator, turbine, and generator. The speed governor senses deviations in frequency and power setting to adjust the hydraulic actuator. This controls the turbine output to balance generator power with load demand and regulate frequency. The control loop maintains small, slow load changes but not large imbalances. The document analyzes the static performance of the speed governor control loop under different network conditions.
- The document compares using two types of smart loads (SLQ and SLBC) for primary frequency control on power systems with high renewable penetration.
- SLBC uses back-to-back converters to provide independent and flexible control of active and reactive power, while SLQ uses reactive compensation.
- Case studies on a 4 generator system and 39 bus New England grid show SLBC more effectively regulates frequency for both over and under-frequency events compared to SLQ.
- SLBC maintains performance for loads near unity power factor where SLQ is ineffective, and requires comparable converter ratings to SLQ for under-frequency events but much less for over-frequency events.
This document presents and compares several control schemes for a Doubly Fed Induction Generator (DFIG) under unbalanced grid voltage conditions. It describes a previously proposed Direct Power Control (DPC) method that uses Notch filters to eliminate harmonic components during voltage unbalances. It also describes a previously proposed Stator Flux Oriented Control (SFOC) method that uses Notch filters and a newly proposed SFOC method that adds a Sequence Component Controller to eliminate negative sequences. Simulations show the enhanced stability of active power, reactive power and generator torque provided by these control schemes under unbalanced voltages.
This document provides an overview of automatic generation control (AGC) in power systems. It includes:
1) Block diagrams showing the components of AGC including speed governors, turbines, generators and load control. The diagrams model the dynamics of these components.
2) Descriptions of the turbine speed governing system, including flyball governors, hydraulic amplifiers and linkage mechanisms used to control steam flow based on generator speed.
3) Equations modeling the dynamics of the speed governor, turbine, and generator-load system and their interaction under different conditions like a load change when the speed changer is fixed.
4) Explanations of concepts like droop characteristic and steady-state frequency deviation from a load
The document presents a new robust load frequency controller for a two area interconnected power system to reduce deviations in frequency and tie line power due to different load disturbances. It develops a dynamic model of the system using integral control and evaluates the system responses. Simulation results in MATLAB/Simulink are provided to study the impact of changing parameters like inertia constant, integration constant, and turbine constant on the frequency deviation and tie line power flow deviation.
As the fifth in a series of tutorials on the power system, Leonardo ENERGY introduces its minute lecture on voltage and frequency control, using the analogy of a metal/rubber plate to demonstrate the centralised nature of frequency control, whereas voltage control is more a local matter.
Firing Angle Control & Constant Current ControlKaushik Naik
This document discusses firing angle control and constant current control techniques for HVDC systems. It describes two main firing angle control schemes: Individual Phase Control (IPC) and Equidistant Pulse Control (EPC). IPC determines firing pulses individually for each valve but causes harmonic instability. EPC produces pulses at equal intervals and has three methods - pulse frequency control, pulse period control, and pulse phase control. It also discusses constant current control and provides references for further reading.
Module 2 ee369 KTU syllabus-high voltage ac generation,resonant circuitsAsha Anu Kurian
Generation of high AC voltages-Testing transformer – single unit testing transformer, cascaded transformer – equivalent circuit of cascaded transformer – generation of high frequency AC voltages- series resonance circuit – resonant transformer – voltage regulation.
This review paper is based on space vector based hysteresis current control in three phase PWM converter. In hysteresis current control technique, two, three or four level hysteresis comparator are used, which selects the appropriate inverter output voltage vectors by their switching phenomenon of vector based HCC, and it is used to control the current vector by keeping the current error vector in tolerance region. Through which the load gets desirable output current voltage. By keeping the zero phase difference between output current and voltage, acquires a high power factor by HCC voltage vector and this HCC voltage vector have some advantages over conventional HCC which are not to have interphase dependency and also maintaining constant modulation frequency or also reducing switching frequency. By this HCC, increase the system steady state performance and reducing dynamic response.
This document discusses a STATCOM controller using resonant control to compensate for voltage and reactive power fluctuations in a wind energy system. It presents a STATCOM model in an ABC reference frame without requiring a PLL. Simulation and experimental results show the controller can effectively regulate the DC link voltage and power quality at the point of common coupling despite wind speed variations between 7-20 m/s. The resonant controller allows operation in the natural frequency domain to mitigate voltage imbalances without delays.
There are three main types of frequency regulation in power grids: flat frequency regulation where individual generators respond to local load changes, parallel frequency regulation where load changes are distributed among multiple generators, and flat-tie line loading where local generators supply local loads while maintaining constant power flow between regions. Frequency in power systems is controlled through generator governors and automatic generation control (AGC) loops. Governor response acts as primary control to instantly adjust generator output to frequency deviations. AGC acts as secondary control to coordinate multiple generators and maintain scheduled interchange power between control areas.
This document proposes a compensation strategy using an Unified Power Quality Compensator (UPQC) device to mitigate power quality issues caused by the injection of wind power into electric grids. The UPQC is controlled using both proportional integral (PI) and fuzzy logic controllers to regulate the wind farm's terminal voltage and filter active and reactive power fluctuations. Simulation results in MATLAB/Simulink are presented to compare the performance of the UPQC using different control strategies, as well as total harmonic distortion calculations.
This document summarizes an investigation into overvoltages caused by ferroresonance in a distribution system consisting of open-delta single-phase voltage transformers. Simulation and experimentation were used to study the phenomenon. Simulation accurately replicated overvoltages observed in experiments of up to 3 per unit. Additional damping resistors were proposed and simulation was used to determine optimal resistor values to mitigate the ferroresonance. Bifurcation diagrams created from simulation results were useful for investigating the ferroresonance behavior under different conditions and determining mitigation techniques.
This document summarizes the dynamic performance investigation of a wind turbine implementing a permanent magnet synchronous generator (PMSG) under variable wind speeds and load conditions when connected to the grid. The PMSG regulates injected active and reactive power using a P-Q control method by controlling the d-axis and q-axis currents. Simulation results using Matlab/Simulink demonstrate the accuracy of the wind turbine model and inverter controller strategy under different test scenarios of changing wind speeds and loads.
The document discusses using a Static Var Compensator (SVC) to increase voltage stability and power limits on a transmission network in Venezuela. It analyzes placing a SVC at the "Malena" bus to:
1) Increase power flow through overhead transmission lines after a three-phase fault at the "Guri" bus, allowing over 48% more power while maintaining voltages between 0.8-1.2 p.u.
2) Maintain voltage levels during transient states like faults and load increases to prevent voltage collapse.
3) The SVC consists of a Thyristor Controlled Reactor (TCR) and fixed capacitors that can generate or absorb reactive power quickly to control voltage
Iaetsd load frequency control for a distributed gridIaetsd Iaetsd
This document discusses load frequency control for a distributed grid system involving wind, hydro, and thermal power plants. It proposes using a PI controller to suppress frequency deviations caused by load and generation fluctuations from renewable resources connected to the grid. It models a system with four thermal plants, a wind farm, and a hydro plant in MATLAB. Load frequency control methods are explored to minimize deviations in area frequency and tie-line power interchange for reliable grid operation with both conventional and renewable resources.
A voltage sensitivity index application for power system load shedding consid...IJAEMSJORNAL
This paper proposes a method for calculating the minimum amount of power load needed to shed and distributing it for each load bus in order to recover the frequency and voltage back to the allowable range. Based on the consideration of the primary control of the turbine governor and the reserve power of the generators for secondary control, the minimum amount of load shedding was calculated in order to recover the frequency of the power system. Computation and analysis of Voltage Sensitivity Index (VSI) of the load bus to prioritize distribution of the amount power load shedding at these positions. The lower the load bus have the Voltage Sensitivity Index (VSI), the higher the amount of load shedding will shed and vice versa. With this technique, frequency and voltage value are still within allowable range, and a large amount of load shedding could be avoided, hence, saved from economic losses, and customer service interruption. The effectiveness of the proposed method tested on the IEEE 37 bus 9 generators power system standard has demonstrated the effectiveness of this method.
The document presents a simple algorithm for distribution system load flow analysis that can accommodate distributed generation. It begins by outlining the objectives, motivation and special features of distribution networks that require modified load flow analysis. It then describes the proposed forward-backward sweep method and models for loads and distributed generation. The algorithm is tested on three test systems and results show reductions in losses and improved voltage profiles with distributed generation integrated using the proposed method and models.
Active Reactive Power Flow Control Using Static Synchronous Series Compensato...IOSR Journals
1) The document discusses using a Static Synchronous Series Compensator (SSSC) and STATCOM to control active and reactive power flow in transmission lines.
2) An SSSC injects a controllable voltage in quadrature with the line current, allowing both capacitive and inductive compensation. A STATCOM regulates voltage by controlling reactive power injection or absorption.
3) Simulation studies were conducted on a two-area, 11-bus system model in MATLAB/Simulink to observe the compensation achieved by installing an SSSC or STATCOM. The system parameters, such as voltage, current, active and reactive power transmissions were monitored with the FACTS devices connected.
This document discusses traction motors and their control. It describes the desirable characteristics of traction motors, including high starting torque, simple speed control, and self-relieving properties. It evaluates the suitability of DC series motors, AC series motors, and linear induction motors for traction applications. It also examines speed control methods for DC traction motors like series parallel control, transition methods, regenerative braking, and the self-relieving property of DC series motors. Numerical examples are provided on series parallel control and regenerative braking.
This paper presents a comprehensive and systematic approach in developing a new switching look-up table for direct power control (DPC) strategy applied to the three-phase grid connected three-level neutral-point clamped (3L-NPC) pulse width modulated (PWM) rectifier. The term of PWM rectifier used in this paper is also known as AC-DC converter. The approach provides detailed information regarding the effects of each multilevel converter space vector to the distribution of input active and reactive power in the converter system. Thus, the most optimal converter space vectors are able to be selected by the switching look-up table, allowing smooth control of the active and reactive powers for each sector. In addition, the proposed DPC utilizes an NPC capacitor balanced strategy to enhance the performance of front-end AC-DC converter during load and supply voltage disturbances. The steady state as well as the dynamic performances of the proposed DPC are presented and analyzed by using MATLAB/Simulink software. The results show that the AC-DC converter utilizing the new look-up table is able to produce almost sinusoidal line currents with lower current total harmonic distortion, unity power factor operation, adjustable DC-link output voltage and good dynamic response during load disturbance.
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.
Power Quality is a combination of Voltage profile, Frequency profile, Harmonics contain and reliability of power supply.
The Power Quality is defined as the degree to which the power supply approaches the ideal case of stable, uninterrupted, zero distortion and disturbance free supply.
This document provides an overview of automatic generation control (AGC) in power systems. It includes:
1) Block diagrams showing the components of AGC including speed governors, turbines, generators and load control. The diagrams model the dynamics of these components.
2) Descriptions of the turbine speed governing system, including flyball governors, hydraulic amplifiers and linkage mechanisms used to control steam flow based on generator speed.
3) Equations modeling the dynamics of the speed governor, turbine, and generator-load system and their interaction under different conditions like a load change when the speed changer is fixed.
4) Explanations of concepts like droop characteristic and steady-state frequency deviation from a load
The document presents a new robust load frequency controller for a two area interconnected power system to reduce deviations in frequency and tie line power due to different load disturbances. It develops a dynamic model of the system using integral control and evaluates the system responses. Simulation results in MATLAB/Simulink are provided to study the impact of changing parameters like inertia constant, integration constant, and turbine constant on the frequency deviation and tie line power flow deviation.
As the fifth in a series of tutorials on the power system, Leonardo ENERGY introduces its minute lecture on voltage and frequency control, using the analogy of a metal/rubber plate to demonstrate the centralised nature of frequency control, whereas voltage control is more a local matter.
Firing Angle Control & Constant Current ControlKaushik Naik
This document discusses firing angle control and constant current control techniques for HVDC systems. It describes two main firing angle control schemes: Individual Phase Control (IPC) and Equidistant Pulse Control (EPC). IPC determines firing pulses individually for each valve but causes harmonic instability. EPC produces pulses at equal intervals and has three methods - pulse frequency control, pulse period control, and pulse phase control. It also discusses constant current control and provides references for further reading.
Module 2 ee369 KTU syllabus-high voltage ac generation,resonant circuitsAsha Anu Kurian
Generation of high AC voltages-Testing transformer – single unit testing transformer, cascaded transformer – equivalent circuit of cascaded transformer – generation of high frequency AC voltages- series resonance circuit – resonant transformer – voltage regulation.
This review paper is based on space vector based hysteresis current control in three phase PWM converter. In hysteresis current control technique, two, three or four level hysteresis comparator are used, which selects the appropriate inverter output voltage vectors by their switching phenomenon of vector based HCC, and it is used to control the current vector by keeping the current error vector in tolerance region. Through which the load gets desirable output current voltage. By keeping the zero phase difference between output current and voltage, acquires a high power factor by HCC voltage vector and this HCC voltage vector have some advantages over conventional HCC which are not to have interphase dependency and also maintaining constant modulation frequency or also reducing switching frequency. By this HCC, increase the system steady state performance and reducing dynamic response.
This document discusses a STATCOM controller using resonant control to compensate for voltage and reactive power fluctuations in a wind energy system. It presents a STATCOM model in an ABC reference frame without requiring a PLL. Simulation and experimental results show the controller can effectively regulate the DC link voltage and power quality at the point of common coupling despite wind speed variations between 7-20 m/s. The resonant controller allows operation in the natural frequency domain to mitigate voltage imbalances without delays.
There are three main types of frequency regulation in power grids: flat frequency regulation where individual generators respond to local load changes, parallel frequency regulation where load changes are distributed among multiple generators, and flat-tie line loading where local generators supply local loads while maintaining constant power flow between regions. Frequency in power systems is controlled through generator governors and automatic generation control (AGC) loops. Governor response acts as primary control to instantly adjust generator output to frequency deviations. AGC acts as secondary control to coordinate multiple generators and maintain scheduled interchange power between control areas.
This document proposes a compensation strategy using an Unified Power Quality Compensator (UPQC) device to mitigate power quality issues caused by the injection of wind power into electric grids. The UPQC is controlled using both proportional integral (PI) and fuzzy logic controllers to regulate the wind farm's terminal voltage and filter active and reactive power fluctuations. Simulation results in MATLAB/Simulink are presented to compare the performance of the UPQC using different control strategies, as well as total harmonic distortion calculations.
This document summarizes an investigation into overvoltages caused by ferroresonance in a distribution system consisting of open-delta single-phase voltage transformers. Simulation and experimentation were used to study the phenomenon. Simulation accurately replicated overvoltages observed in experiments of up to 3 per unit. Additional damping resistors were proposed and simulation was used to determine optimal resistor values to mitigate the ferroresonance. Bifurcation diagrams created from simulation results were useful for investigating the ferroresonance behavior under different conditions and determining mitigation techniques.
This document summarizes the dynamic performance investigation of a wind turbine implementing a permanent magnet synchronous generator (PMSG) under variable wind speeds and load conditions when connected to the grid. The PMSG regulates injected active and reactive power using a P-Q control method by controlling the d-axis and q-axis currents. Simulation results using Matlab/Simulink demonstrate the accuracy of the wind turbine model and inverter controller strategy under different test scenarios of changing wind speeds and loads.
The document discusses using a Static Var Compensator (SVC) to increase voltage stability and power limits on a transmission network in Venezuela. It analyzes placing a SVC at the "Malena" bus to:
1) Increase power flow through overhead transmission lines after a three-phase fault at the "Guri" bus, allowing over 48% more power while maintaining voltages between 0.8-1.2 p.u.
2) Maintain voltage levels during transient states like faults and load increases to prevent voltage collapse.
3) The SVC consists of a Thyristor Controlled Reactor (TCR) and fixed capacitors that can generate or absorb reactive power quickly to control voltage
Iaetsd load frequency control for a distributed gridIaetsd Iaetsd
This document discusses load frequency control for a distributed grid system involving wind, hydro, and thermal power plants. It proposes using a PI controller to suppress frequency deviations caused by load and generation fluctuations from renewable resources connected to the grid. It models a system with four thermal plants, a wind farm, and a hydro plant in MATLAB. Load frequency control methods are explored to minimize deviations in area frequency and tie-line power interchange for reliable grid operation with both conventional and renewable resources.
A voltage sensitivity index application for power system load shedding consid...IJAEMSJORNAL
This paper proposes a method for calculating the minimum amount of power load needed to shed and distributing it for each load bus in order to recover the frequency and voltage back to the allowable range. Based on the consideration of the primary control of the turbine governor and the reserve power of the generators for secondary control, the minimum amount of load shedding was calculated in order to recover the frequency of the power system. Computation and analysis of Voltage Sensitivity Index (VSI) of the load bus to prioritize distribution of the amount power load shedding at these positions. The lower the load bus have the Voltage Sensitivity Index (VSI), the higher the amount of load shedding will shed and vice versa. With this technique, frequency and voltage value are still within allowable range, and a large amount of load shedding could be avoided, hence, saved from economic losses, and customer service interruption. The effectiveness of the proposed method tested on the IEEE 37 bus 9 generators power system standard has demonstrated the effectiveness of this method.
The document presents a simple algorithm for distribution system load flow analysis that can accommodate distributed generation. It begins by outlining the objectives, motivation and special features of distribution networks that require modified load flow analysis. It then describes the proposed forward-backward sweep method and models for loads and distributed generation. The algorithm is tested on three test systems and results show reductions in losses and improved voltage profiles with distributed generation integrated using the proposed method and models.
Active Reactive Power Flow Control Using Static Synchronous Series Compensato...IOSR Journals
1) The document discusses using a Static Synchronous Series Compensator (SSSC) and STATCOM to control active and reactive power flow in transmission lines.
2) An SSSC injects a controllable voltage in quadrature with the line current, allowing both capacitive and inductive compensation. A STATCOM regulates voltage by controlling reactive power injection or absorption.
3) Simulation studies were conducted on a two-area, 11-bus system model in MATLAB/Simulink to observe the compensation achieved by installing an SSSC or STATCOM. The system parameters, such as voltage, current, active and reactive power transmissions were monitored with the FACTS devices connected.
This document discusses traction motors and their control. It describes the desirable characteristics of traction motors, including high starting torque, simple speed control, and self-relieving properties. It evaluates the suitability of DC series motors, AC series motors, and linear induction motors for traction applications. It also examines speed control methods for DC traction motors like series parallel control, transition methods, regenerative braking, and the self-relieving property of DC series motors. Numerical examples are provided on series parallel control and regenerative braking.
This paper presents a comprehensive and systematic approach in developing a new switching look-up table for direct power control (DPC) strategy applied to the three-phase grid connected three-level neutral-point clamped (3L-NPC) pulse width modulated (PWM) rectifier. The term of PWM rectifier used in this paper is also known as AC-DC converter. The approach provides detailed information regarding the effects of each multilevel converter space vector to the distribution of input active and reactive power in the converter system. Thus, the most optimal converter space vectors are able to be selected by the switching look-up table, allowing smooth control of the active and reactive powers for each sector. In addition, the proposed DPC utilizes an NPC capacitor balanced strategy to enhance the performance of front-end AC-DC converter during load and supply voltage disturbances. The steady state as well as the dynamic performances of the proposed DPC are presented and analyzed by using MATLAB/Simulink software. The results show that the AC-DC converter utilizing the new look-up table is able to produce almost sinusoidal line currents with lower current total harmonic distortion, unity power factor operation, adjustable DC-link output voltage and good dynamic response during load disturbance.
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.
Power Quality is a combination of Voltage profile, Frequency profile, Harmonics contain and reliability of power supply.
The Power Quality is defined as the degree to which the power supply approaches the ideal case of stable, uninterrupted, zero distortion and disturbance free supply.
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.
Power quality-disturbances and monitoring SeminarSurabhi Vasudev
The document provides an overview of power quality monitoring and automatic power quality disturbance classification. It defines power quality and discusses increased interest in power quality. It describes various power quality disturbances like voltage fluctuations, harmonics, sags, and swells. It then discusses automatic power quality disturbance classifiers which use techniques like segmentation, feature extraction, and classification to identify different disturbance types. Neural networks and expert systems are presented as methods for automatic classification. The document emphasizes the importance of power quality monitoring and classification systems.
Injection of the wind power into an electric grid affects the power quality. The performance of the wind turbine and thereby power quality are determined on the basis of measurements and the norms followed according to the guideline specified in International Electro-technical Commission standard, IEC-61400. The influence of the wind turbine in the grid system concerning the power quality measurements are-the active power, reactive power, variation of voltage, flicker, harmonics, and electrical behavior of switching operation and these are measured according to national/international guidelines. The paper study demonstrates the power quality problem due to installation of wind turbine with the grid. In this proposed scheme STATic COMpensator (STATCOM) is connected at a point of common coupling with a battery energy storage system (BESS) to mitigate the power quality issues. The battery energy storage is integrated to sustain the real power source under fluctuating wind power. The STATCOM control scheme for the grid connected wind energy generation system for power quality improvement is simulated using MATLAB/SIMULINK in power system block set. The effectiveness of the proposed scheme relives the main supply source from the reactive power demand of the load and the induction generator. The development of the grid co-ordination rule and the scheme for improvement in power quality norms as per IEC-standard on the grid has been presented.
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.
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.
Simulation of D-STATCOM to study Voltage Stability in Distribution systemijsrd.com
This document presents a simulation study of a D-STATCOM (Distribution Static Compensator) to improve voltage stability in a distribution system. It first provides background on voltage dips and describes the structure of a STATCOM, which includes a voltage source inverter, transformer, and controller. The simulation model of the D-STATCOM and distribution network is developed using SimPowerSystems blocks. Simulation results show that without the D-STATCOM, voltage dips to 0.93 p.u. during a load change, but with the D-STATCOM the voltage is stabilized at 1.0 p.u., demonstrating its effectiveness in mitigating power quality issues like voltage instability.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
PWM control techniques for three phase three level inverter drivesTELKOMNIKA JOURNAL
In this paper two very efficient pulse width modulation techniques were discussed named Sin pulse width modulation and space vector pulse width modulation. The basic structure of the three-level inverter neutral-point clamped is introduced and the basic idea about space vector pulse width modulation for three-level voltage source inverter has been discussed in detail. Nearest three vectors space vector pulse width modulation control algorithm is adopted as the control strategy for the three phase three level NPC inverter in order to compensate the neutral-point shifting. Mathematical formulation for calculating switching sequence has determined. Comparative analysis proving superiority of the space vector pulse width modulation technique over the conventional pulse width modulation, and the results of the simulations of inverter confirm the feasibility and advantage of the space vector pulse width modulation strategy over sin pulse width modulation in terms of good utilization of dc-bus voltage, low current ripple and reduced switching frequency. Space vector pulse width modulation provides advantages better fundamental output voltage and useful in improving harmonic performance and reducing total harmonic distortion.
Total Harmonic Distortion of Dodecagonal Space Vector ModulationIJPEDS-IAES
Space vector modulation technique is one of the best PWM techniques which have been implemented to the Multilevel inverter circuit to get the purely sinusoidal cuurent. This is a important algorithm which is implemented in open wind induction motor. This type of I.M has great impact on Electric Drive system. SVM is nothing but the technique of switching algorithm. The Hexagonal space vector modulation has been implemented before, but elimination of higher order harmonics is not possible. Torque pulsation arises. Speed control of Induction motor was not smooth. So Dodecagonal (12) structure developed. A 12 side polygonal space vector structure is meant for eliminating (6n±1) harmonics in the phase current waveform throughout the modulating range. A high resolution of PWM technique is proposed involving multiple 12 sided polygonal (Dodecagonal) structure that can generate highly sinusoidal voltage at a reduced switching frequency. In this paper different values of frequencies have been taken for harmonic analysis. SVM method features a higher level of dc-bus voltage utilization compared to the conventional PWM.
Impacts of Distributed Generation on Power QualityParth Patel
This paper studies the impacts of distributed generation, specifically solar and wind power, on power quality when interconnected to a distribution utility feeder. Multiple scenarios were modeled and simulated using the RSCAD/RTDS real-time simulation tool. The results show some increase in harmonic distortion and voltage fluctuations with the addition of distributed generation, but within acceptable limits. Harmonics were observed at higher orders which could impact power quality. Voltage fluctuations increased nearer to the distributed generation sources.
The document discusses the design and simulation of a three-level neutral point clamped (NPC) inverter. It describes the topology of the NPC inverter, which uses twelve IGBT switches and diodes arranged into three phases to generate a three-phase AC output from a DC input voltage. An open-loop pulse width modulation control scheme is used to switch the IGBTs. Simulation results show the output voltages achieve less than 1.1% total harmonic distortion, demonstrating the NPC inverter's ability to reduce harmonics compared to other inverter types. The document concludes the NPC inverter is well-suited for applications like solar power due to its high efficiency and power quality.
Performance Analysis Of Induction Motor For Voltage Mode And Current Mode Con...IRJET Journal
This document discusses the performance analysis of an induction motor using voltage mode and current mode control. It compares hysteresis current control and space vector pulse width modulation (SVPWM). Hysteresis control directly limits current peaks but SVPWM provides higher voltage output and lower harmonic distortion. The document simulates an induction motor drive using SVPWM-based hysteresis current control in MATLAB. Key steps include Clark transformation to generate reference signals, switching between active and zero vectors to synthesize the reference signal, and using hysteresis control to generate PWM signals from current errors. Simulation results show the SVPWM controller provides good speed and current regulation for the induction motor.
The study made in this paper concerns the use of the voltage-oriented control (VOC) of three-phase pulse width modulation (PWM) rectifier with constant switching frequency. This control method, called voltage-oriented controlwith space vector modulation (VOC-SVM). The proposed control scheme has been founded on the transformation between stationary (α-β) and and synchronously rotating (d-q) coordinate system, it is based on two cascaded control loops so that a fast inner loop controls the grid current and an external loop DC-link voltage, while the DC-bus voltage is maintained at the desired level and ansured the unity power factor operation. So, the stable state performance and robustness against the load’s disturbance of PWM rectifiers are boths improved. The proposed scheme has been implemented and simulated in MATLAB/Simulink environment. The control system of the VOC-SVM strategy has been built based on dSPACE system with DS1104 controller board. The results obtained show the validity of the model and its control method. Compared with the conventional SPWM method, the VOC-SVM ensures high performance and fast transient response.
This paper presents an analysis of virtual-flux direct power control (VFDPC) technique for the three-phase pulse width modulation (PWM) ac-dc converter. The proposed VFDPC is developed by assuming the grid voltage and converter line filters quantities are related to a virtual three-phase ac motor. The controller works with less number of sensors by eliminating the voltage sensors used for measuring the three-phase grid voltage. The grid virtual flux which is proportional to the grid voltage will be estimated from the information of converter switching states, line current, and dc-link output voltage. Several analyses are performed in order to study the steady state and dynamic performance of the converter, particularly during the load and DC voltage output reference variations. The proportional integral (PI) controller at the outer voltage control loop of VFDPC is tuned properly and the entire PWM ac-dc converter system is simulated using MATLAB/Simulink to ensure the dc output voltage follow the desired output voltage under steady state and dynamic conditions. Ac-dc converter utilizing the proposed VFDPC is able to generate three-phase input current waveforms that are almost sinusoidal with low harmonics contents which is less than 5% and near unity power factor (pf) operation.
Load Flow and PV Curve Analysis of a 220kV SubstationIRJET Journal
This document discusses load flow analysis and PV curve analysis of a 220kV substation. It presents the methodology used, which includes collecting data from the substation, developing a bus network model, performing load flow analysis using the Newton-Raphson method in MATLAB, and generating PV curves in PowerWorld simulator. The analysis was conducted on two cases with different circuit configurations. The results show voltages, power flows, line losses and identify the knee point of PV curves. Capacitor compensation is also analyzed, showing it can improve voltage stability. The study highlights the importance of load flow analysis for maintaining power system stability and performance.
Total Harmonic Distortion Analysis of Multilevel Inverter Fed To Induction Mo...IJERA Editor
This paper presents the control of a multilevel inverter supplied by a Photovoltaic (PV) panel and a batteries
bank. It is well known that the power quality of multilevel inverter signals depends on their number of levels.
However, the question that arises is whether there is a limit beyond which it is not necessary to increase the
number of level. This question is addressed in this paper. Three, nine and fifteen-level converters are studied.
The harmonics content of the output signals are analyzed. A simplified Pulse Width Modulation (SPWM)
method for a multilevel inverter that supplied an induction motor is developed. The controller equations are such
that the SPWM pulses are generated automatically for any number of levels. The effectiveness of the propose
method is evaluated in simulation. Matlab®/ Simulink is used to implement the control algorithm and simulate
the system.
This document summarizes a research article that proposes using a Unified Power Quality Compensator (UPQC) device to regulate voltage and mitigate fluctuations at a weak grid connection to a wind farm. The UPQC uses internal control strategies to regulate the voltage at the wind farm terminals using its series converter, and uses its shunt converter to filter wind farm power and prevent voltage fluctuations. The control strategy manages active and reactive power sharing between the series and shunt converters through a common DC link. Simulation results showed the UPQC approach effectively regulated voltage during load changes and rejected power fluctuations from tower shadow effects at the wind turbines.
1) The document presents a new zero-voltage switching (ZVS) topology for a three-phase grid-connected inverter. The topology uses an additional active clamping leg to achieve ZVS for all the main switches.
2) A new space vector modulation scheme is proposed to control the inverter such that the auxiliary switch operates at the same frequency as the main switches. This ensures ZVS turn-on of the main switches.
3) Simulation results on a 30kW prototype verify that the ZVS topology reduces switching losses, improves efficiency, and makes the inverter suitable for practical high power applications.
Power Quality Improvement Using Custom Power Devices in Squirrel Cage Inducti...IJPEDS-IAES
1) The document describes a system using a UPQC (Unified Power Quality Conditioner) to improve power quality when connecting a squirrel cage induction generator wind farm to a weak grid. The UPQC regulates the wind farm terminal voltage and mitigates harmonics at the point of common coupling.
2) It uses a neuro-fuzzy control strategy to manage the active and reactive power exchange between the series and shunt converters of the UPQC via the DC link.
3) Simulation results show the UPQC is able to compensate for voltage fluctuations at the point of common coupling due to variations in wind power generation and regulate the voltage during load connection/disconnection events.
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
Simulation of 3-phase matrix converter using space vector modulationIJECEIAES
This paper illustrates the simulation of 3-phase matrix converter using Space Vector Modulation (SVM). Variable AC output voltage engendered using matrix converter with bidirectional power switches controlled by appropriate switching pulse. The conventional PWM converter engenders switching common mode voltage across the load system terminals, which cause to common mode current and its leads to bearing failure in load drive. These problems can be rectified using SVM and which minimize the effect on the harmonic fluctuation in AC output voltage and stress on the power switch is reduced using bidirectional switch for proposed 3-phase matrix converter. The simulation results have been presented to validate the proposed system using matlab / simulink.
Fuzzy Logic Controller Based High Frequency Link AC-AC Converter For Voltage ...IJTET Journal
Abstract—In this paper, an advanced high frequency link AC-AC Push-pull cycloconverter for the voltage compensation is proposed in order to maintain the power quality in electric grid. The proposed methodology can be achieve arbitrary output voltage without using large energy storage elements. So that the system is more steadfast and less costly compared with the conventional inverter topology. Additionally, the proposed converter does not contain any line frequency transformer, which reduces the cost further. The control scheme for the push pull cycloconverter employs the fuzzy logic controller based sinusoidal pulse width modulation (SPWM) to accomplish better performance on voltage compensation, like unbalanced voltage harmonics elimination. The simulation results are given to show the effectiveness of the proposed high frequency link AC-AC converter and fuzzy logic controller based SPWM technology
Simulation and Comparison of DVR and DSTATCOM Used for voltage sag mitigation...paperpublications3
Abstract: Power Quality problem in a system leads to various disturbances such as voltage fluctuations, transients and waveform distortions that results in a mis-operation or a failure of end user equipment. There are different types of custom power devices like Distribution Static Compensator (D-STATCOM) and Dynamic Voltage Restorer (DVR) which can effectively use for mitigation of different type of power quality problems. This paper describes the technique of correcting the supply voltage sag distributed system and also describes performance comparison are presented between DVR and DSTATCOM to know how both the devices successfully been applied to power system for regulating system voltage effectively. DSTATCOM and DVR both of them based on VSI principle. A DVR is a series compensation device which injects a voltage in series with system and a DSTATCOM is a shunt compensation device which injects a current into the system to correct the power quality problems. This paper presents a power system operation with PI controller with abc to dq0 convertor approach. Total Harmonics Distortion (THD) is also calculated for the system with and without compensation. Results are presented to assess the performance of devices as a potential custom power solution. Improve dynamic voltage control and thus increase system load ability. This paper presents modeling and simulation of DVR & DSTATCOM in MATLAB/Simulink.
This document analyzes voltage unbalance on Uganda's distribution network by measuring voltage and current profiles at distribution transformers on the Kigo feeder. Phase voltage unbalance rates were calculated and compared to phase currents. High unbalance was found at the Najja Central transformer likely due to transformer issues. Other transformers had unbalanced phase currents causing unbalance. Periodic audits are suggested to identify problematic transformers which can then have loads reconfigured or transformers replaced to mitigate unbalance. Automatic switching or power filters may also help but are more complex and costly to implement.
Space Vector of Three Phase Three level Neutral Point Clamped Quasi Z Source ...IJTET Journal
Space vector of three phase three level neutral point clamped quasi z source inverter is proposed in this paper. Space vector modulation is the pulse width modulation consists of number of switching states. Space vector pulse width modulation technique utilizes 15% more power from DC source. Harmonics are reduced by the presence of switching states. Quasi Z-source inverter is advanced topologies which performs both boost and buck operation of a converter. The proposed inverter obtains continuous input current and the boost converter is not needed. So, maximum voltage can be obtained in the load and system complexity is reduced. Maximum power can be obtained from the solar panel by using MPPT. The implementation of MPPT is to operate a PV array under constant voltage and power reference to modify the duty cycle of the inverter.The simulation of proposed topology is done in MATLAB/SIMULINK software.
Gender challenges in clean energy sector can networkRCREEE
Women play an important role in the clean energy sector but face challenges. Case studies from Yemen, Lebanon, the UAE, and Palestine show successful women entrepreneurs and leaders in solar energy. However, women face barriers to securing funding, building partnerships, and educating stakeholders. Actions to address the gender gap include strengthening international cooperation, providing targeted funding, improving access to networks, and supportive policies to promote gender equality in clean energy.
Climate and energy policies advocacy of youth in the arab worldRCREEE
The document summarizes a regional project aimed at strengthening the advocacy capacities of youth in the Arab world on climate and energy policies. It discusses objectives to build skills in energy and climate fields and integrate societal aspects like gender disparities. A key output is a policy paper presenting recommendations from 12 young professionals and activists from 10 Arab countries (majority women) to regional decision-makers on energy visions and policies. The project also aims to empower women in sustainable energy and give them a platform to influence decision-making processes.
Women in energy a world full of opportunities lcecRCREEE
Ms. Patil Mesrobian, Program Development Officer, LCEC presentation at Sustainable Energy Field: A Step towards Sustainable Communities - Workshop on the side of International Beirut Energy Forum on 25 September 2019.
Green Mind is a Lebanese non-profit founded in 2012 primarily by women seeking to promote sustainable practices. Led by a woman, Green Mind hopes to inspire other women to take on environmental challenges. It recognizes leadership in sustainability through various awards and organizes projects in areas like education, energy, water, transport, and waste. Green Mind also created mobile apps like GreenMiles for carpooling and one for reforestation efforts to promote environmental causes through technology.
Many initiatives are currently blossoming across the region facilitating a stronger engagement of females in clean energy.
Salma El Shiekh, The Sudanese Artik Energy Start up founder shared her journey at Sustainable Energy Field: A Step towards Sustainable Communities - Workshop on the side of International Beirut Energy Forum on 25 September 2019.
Many initiatives are currently blossoming across the region facilitating a stronger engagement of females in clean energy.
Eng. Zainab Garashi, Founder & CEO, Engineers without Boarders- Kuwait presented EWB projects at Sustainable Energy Field: A Step towards Sustainable Communities - Workshop on the side of International Beirut Energy Forum on 25 September 2019.
Women in Energy in Jordan Challenges, Opportunities and the Way Forward JREEE...RCREEE
Many initiatives are currently blossoming across the region facilitating a stronger engagement of females in clean energy.
Eng. Lina AL-Mubaideen presented JREEEF programs and Initiatives in Sustainable Energy Field: A Step towards Sustainable Communities - Workshop on the side of International Beirut Energy Forum on 25 September 2019.
Women in energy sector in the mena region rcreeeRCREEE
Introducing the latest perspectives on gender engagement in the workforce with specific focus on clean energy by Eng. Sara Ibrahim, RCREEE Senior Expert at Enabling Women in Sustainable Energy Field: A Step towards Sustainable Communities - Workshop on the side of
International Beirut Energy Forum on 25 September 2019.
Awakening diversity in the clean energy sector a key point to achieve sustai...RCREEE
Introducing the latest perspectives on gender engagement in the workforce with specific focus on clean energy by Ms. Fatma M'Selmi Baklouti, CEO & Founder Laur' us Consulting at Enabling Women in Sustainable Energy Field: A Step towards Sustainable Communities - Workshop on the side of
International Beirut Energy Forum on 25 September 2019.
Mitigating environmental impact in non renewable energy the role of womenRCREEE
Introducing the latest perspectives on gender engagement in the workforce with specific focus on clean energy by Ms. Diana Kaissy, Executive Director, The Lebanese Oil and Gas Initiative-LOGI at Enabling Women in Sustainable Energy Field: A Step towards Sustainable Communities - Workshop on the side of
International Beirut Energy Forum on 25 September 2019.
These are the key messages of the first High Level Policy Dialogue to promote RE and EE in the Mediterranean region. The messages were delivered by Dr. Badr
The presentation is prepared as an introduction for the first High Level Policy Dialogue to promote RE and EE in the Mediterranean region by Eng. Kraidy
EU-Egypt Energy Cooperation: A successful modelRCREEE
This document discusses EU-Egypt energy cooperation and outlines key energy challenges in Egypt. It summarizes achievements in EU-Egypt energy cooperation including projects supporting renewable energy, energy efficiency, and regulatory capacity. It presents the Second Memorandum of Understanding between Egypt and EU for 2018-2022 focusing on gas and electricity sector reforms, renewable energy projects, and technological cooperation. The European Investment Plan is introduced as a three-pillar structure to mobilize investment through technical assistance, improved investment climate, and financing from the European Fund for Sustainable Development. Potential energy investment projects are listed in renewable energy, energy efficiency, and grid infrastructure totaling over 1.7 billion Euros.
Global Energy Interconnection Enhances Renewable Energy Development & Regiona...RCREEE
The document discusses global energy interconnection (GEI) and the Global Energy Interconnection Development and Cooperation Organization (GEIDCO). It summarizes GEIDCO's view of GEI as an infrastructure platform to massively develop, transmit, and utilize clean energy worldwide using ultra-high voltage grids and smart grid technology. The document outlines GEIDCO's management structure, membership, and regional offices. It provides examples of cooperation projects between countries to interconnect power grids and develop clean energy. Finally, it presents GEIDCO's proposed roadmap and backbone network for the development of GEI over domestic, intra-continental, and intercontinental phases by 2050.
Report summary on Intended Nationnally determined contributions -Comprehensiv...RCREEE
This document provides a summary of Intended Nationally Determined Contributions (INDCs) and Nationally Determined Contributions (NDCs) from 20 Arab countries. It finds that these plans outline both unconditional and higher conditional emission reduction targets. Cost estimates total over $109 billion, with 71% of costs listed as conditional on international support. Adaptation actions are generally lower cost than mitigation and focus on sectors beyond energy. Countries' plans emphasize renewable energy development as well as energy efficiency across sectors. Water desalination and carbon capture storage are mentioned in relation to these areas. Overall, the plans indicate ambitions to increase clean energy and jobs while reducing emissions, though voluntary targets may need to become mandatory with regional coordination.
Energy productivity as a new paradigm for sustainable energy transitionsRCREEE
1. Energy productivity is a new policy paradigm that focuses on improving the value obtained from energy consumption through greater energy efficiency, structural economic reforms, and other energy and climate policies.
2. A report by KAPSARC and UNESCWA examined energy productivity in Saudi Arabia and found that diversification efforts and energy efficiency are transitioning the country to a lower energy intensity pathway in line with its Vision 2030 goals.
3. The report discusses how industrial strategy and policy can further increase Saudi Arabia's energy productivity by developing higher value added industries and strengthening local supply chains.
Arab Region Progress in Sustainable Energy Challenges and OpportunitiesRCREEE
The document summarizes the current status of sustainable energy in the Arab region and key challenges. Near-universal electricity access has been achieved in cities, but rural access remains around 80%. Energy consumption has more than doubled since 1990, with renewables playing a marginal role at 4% of energy. Barriers to expanding renewable energy and energy efficiency include high costs, lack of incentives, and insufficient policies. Universal access to electricity and clean cooking fuels has not been achieved. Water scarcity and dependence on fossil fuels are significant regional challenges. Promoting investments, technology, capacity building, and data are priorities to meet development and climate goals.
2. Zafarana Wind Farm studies
Power Quality Assessment
Transformer No. 2 [75 MVA]
Installed capacity [64.9 MW]
Conducted By :
Sayed M. Mansour
[NREA, Hurghada Wind Farm ]
Wind Energy Technology Center, February 2006
3. Preface
Power quality is an issue of increasing importance, the main reason for
this is the increasing demands from the customers with respect to security
and quality of supply in order for them to rely on the public power supply in
such as way that they do not have to take special measures to ensure that
they can conduct their business without concern about the availability of
computers, machines, appliance etc
4. Introduction
• The study should primarily be seen as an initiation and illustration of
possibilities for activities and studies regarding wind farms at Zafarana.
• The main task of the study is to evaluate the wind farm performance
and electrical properties as well as the wind farm impact on power
quality.
5. Objective
The objective of power quality assessment task is to:
• Illustrate the wind farm impact on power quality in terms of reactive
consumption, voltage and frequency deviations.
• Analyze the measurements taken and relate the results obtained to
international standards and theoretical calculations.
6. Description of the Site
Zafarana wind Farm
• Zafarana is situated along
the coast of Suez Gulf, 220
km south of Cairo.
• Annual Average Wind
Speed is 9.5 m /s
• Flat Area
• Low Turbulence
• High Capacity Factor
8. Zafarana Substation
• Zafarana wind farm has been linked to the national grid via a
transformer substation located few kilometers north of the site;
substation has two stationary transformers and mobile one. The
substation has many incoming and outgoing coupling points, as
shown in the flowing figures.
12. Data Acquisition and Analysis
• The power analyzing system consists of a Voltech PM300 power
analyzer, laptop PC, and a data logging program called PM300.EXE
developed in the programming language Quick Basic 4.5 by Risø
National Laboratory.
• The Voltech PM300 power analyzer performs the actual power
measurements, whereas the Basic program PM300.EXE running on
the laptop computer controls the power analyzer and logs data from it.
13. The Measurements
• The measurements were carried out at Zafarana substation on 22 kV
Bus Bar, the substation has no single feeder with the total output power
of the wind farm, thereby a direct measurements of the total output
power is not possible. At substation there are two permanent transformer
and mobile one, in order to measure the total power, the currents of the
three transformers (TR.1, TR.2 and mobile one) must be summed
simultaneously using summation transformer where it was not available
during the measurements period.
• According to the situation at zafarana substation, it is decided to achieve
the measurements individually on transformer No. 2 and transformer No.
1, thereby the measurement equipments had been connected to the
secondary side of the potential transformer (22000/100 V) to measure
the voltage, as well as the current measured using current clamps (1 mV:
1 mA) on the secondary side of the existing current transformer (2000:1
A) of transformer No.2.
14. Measurements d Analysis
Key data for Zafarana wind farm measurements
Item Description
Start Date 17/8/2005
Stop Date 14/9/2005
Nominal power 64.9 MW
Max. output power (10-minute average) 55.06 MW
Min. output power (10-minute average) - 0.3 MW
Mean. output power (10-minute average) 42.12 MW
Mean PF (10-minute average) 0.91
Mean CF (10-minute average) 64.9
Mean Bus-Bar Voltage (10-minute 21.95 kV
average)
15. Bus-Bar Voltage
• The valid measurement with the power analyzer on 22 kV Bus-Bar
give basis for assessing the voltage quality and to analyze the impact
of the wind farm on the voltage quality.
• International standard (IEC-Ref 3) specifies that the voltage level
should be within ± 5 % of its nominal value measured as 10-minute
average data or ± 10 % of its measured instantaneous values.
16. • Plot (1) is the statistical data of the mean value of the Bus-Bar voltage,
the voltage level during the measurement period between 21.06 kV and
22.73 kV, or in other words 22 kV +3.3% and – 4.27%.
• From the results obtained it could be stated that the voltage level when
reaches to its maximum value still within the required limit, meanwhile it
is critical when reaches to its minimum
17. • Plot (2) is the statistical data as 10-minute average values of the Bus-Bar
voltage plotted versus the active power.
• The Bus-Bar voltage seems to be constant independent of the output power
(scattered points).
• The cloudy points where the voltage decreases for increasing the generated
power (from 30 to 55 MW)
18. • Plot(3) is the statistical data of the three phase voltages as 10-minute
average during the measurement period., the three phase voltages limits
are indicated below:-
• Phase No. 1 varies from 12.07 kV to 13.04 kV, or 12.7 kV + 2.66 % and -
4.95 %.
• Phase No. 2 varies from 12.40 kV to 13.40 kV, or 12.7 kV + 5.50 % and -
2.14 %.
• Phase No. 3 varies from 11.98 kV to 12.93 kV, or 12.7 kV + 1.80 % and
- 5.70 %.
19. • Plot(4) is the absolute value of the frequency distribution as 10-minute
average value of the Bus-Bar voltage, there are two different situations are
clearly observable in the plot, the first is the distribution is not symmetrical
around the nominal value (22 kV) (Z0).
• The second is that two peaks are noticed at 22.1 kV and 22.2 kV, as well
as the voltage range is quite narrow due to the wind farm connected to a
large network. The voltage varies almost from 21.3 kV (Z1) to 22.7 kV (Z2)
during the measurement period.
20. Vreltive={ (vmean- Vinitial) /vinitial}*100
• Plot (5) is the voltage change relative to the initial (nominal) value “22 kV”
from one 10-minute value to the next, the majority of the relative voltage
changes are between +2.2 % and -2.6 % as magnitude (bin).
• The plot shows that voltage varies in a small range and very few values
above +3 % occur. No significant peaks are noticed in the plot, as well as
the distribution is not symmetrical around ZO (when Vmean = Vinitial).
21. • Plot (6) is the diurnal pattern for the mean, maximum and minimum value
of the Bus-Bar voltage, the plot is the typical value of the Bus-Bar voltage
profile, since the plot is the average value throughout the measurement
period.
22. • Plot (7) is the diurnal pattern of the three phase voltages as 10-minute
average, it is clearly seen in the plot that phase No. 1 and phase No. 3 are
slightly lower than phase No. 2.
23. • Plot (8) is the diurnal pattern of the grid voltage and grid frequency, the
plot shows that the grid frequency is almost constant independent of the
Bus-Bar voltage level.
24. • Plot (9) illustrates the diurnal pattern of the Bus-Bar voltage and active
power, the plot shows that the voltage varies reversely to the active power.
Assuming a fairly relation between the voltage and the output power, it is
obviously seen in the plot that the maximum value of active power (50.9
MW) corresponds to minimum value of voltage (21.5 kV) as 10-minute
average value.
25. • Plot (10) is the diurnal pattern of the Bus-Bar voltage and mean wind speed,
the plot indicates that the voltage values seem to vary reversely to the wind
speed values. The plot corresponds with voltage-power correlation as shown
in Plot (9).
26. Line Current
• Plot (11) is the statistical data of the line current as 10-minute average
during the measurement period.
27. • Plot (12) is the diurnal pattern of mean, maximum and minimum values
of line current. The plot is the typical value of the line current profile as
the plot is the average of the measurement period.
• The maximum value looks constant; meanwhile, the mean and minimum
values look fluctuated very much.
28. • Plot (13) is the statistical data of a correlation between the output active
power and line current as 10-minute average value, the plot shows that the
power varies proportionally to the line current; however, there is a situation
where, a small deviation has been occurred.
• The raw data (Time series as 10-sec.) has been investigated carefully, and it
is concluded that the current reading of phase No.1 was not match (lower
than) with the other two phases, only on day 7/9/2005. The reason for this
till k
29. • Plot (14) illustrates the diurnal pattern of active power and line current as 10-
minute average, the plot shows that the output power varies proportionally to
the line current.
30. • Plot (15) is the diurnal pattern of three phase line currents as
mean value. The plot is the typical values of the three-phase
currents profile as the plot is the average throughout the
measurement period
31. • Plot (16) is the statistical data of the load factor as 10-minute average
value; the load factor is 0.96 as an average value as shown in the plot.
32. Grid Frequency
• Plot (17) is the statistical data of the grid frequency profile as 10-minute
average values. It is seen from the plot that the grid frequency is very stable
independent of other grid parameters; the average value is 49.96 Hz during
the measurement period.
• The plot shows that the frequency lays within a narrow band between 49.86
Hz and 50.13 Hz that comply with the international standards (50 Hz ± 1 %).
33. • Plot (18) is the statistical data of a correlation between the grid frequency
and active power, the grid frequency remains constant independent of the
produced power from the wind turbines.
• It is noticed also that the cloudy points in the plot is quit wide at high output
power from the farm, however, the changes in the frequency still in a very
small range.
34. • Plot (19) is the absolute change of the frequency distribution as 10–minute
average values of the grid frequency, it is obviously seen in the plot that,
the frequency is well controlled with only small deviations from the 50 Hz
nominal setting, these small deviations are slightly above 50 Hz.
• The grid frequency is quite symmetrical and triangular around 49.98 Hz,
varying from 49.92 Hz to 50.03 Hz.
35. • Plot (20) is the diurnal pattern of the mean, maximum and minimum values
of the grid frequency, the plot emphasis the result obtained in Plot (19).
36. • Plot (21) is the statistical data of mean, maximum and minimum values of
grid frequency as 10-minute average value.
37. Voltage Harmonics
• Plot (22) is the statistical data as 10-minutes average value of the Total
Harmonic Distortion (THD) of the Bus-Bar voltage.
• It can be seen from the plot that the measured THD within the measurement
period are between 0.3 % and 3.11 %, which comply with the international
standards (Voltage THD should less than 5% measured as 10-minute
average) for supply voltage characteristics.
38. • Plot (23) is the statistical data of a correlation between voltage THD and
active power as 10-minute average value, the maximum value (3.11%) of
THD occurred at 0.5 MW, indicating no particular relation between the output
active power and the voltage THD, but the voltage THD follows the daily
load pattern.
39. • Plot (24) is the voltage THD in case of high and low wind speed, the plot
emphasizes the fact that the wind turbines are not responsible for causing
any significant harmonic distortion, in particular, the wind turbines at the site
are fixed-speed with induction generator (without a power electronic
converter).
40. • Plot (25) is the diurnal pattern of the mean and maximum values of the total
harmonic distortion of the Bus-Bar voltage.
• The plot is the typical voltage THD profile since the plot is the average value
throughout the measurement period.
41. • Plot (26) illustrate the absolute value of the frequency distribution of the
voltage THD, the plot does not show any particular features except for a
low mean value of THD.
42. Current Harmonics
• Plot (27) is the statistical data as 10-minute average value of the line current
THD, it is clearly seen from the plot that there is a peak of 70 % of THD, and
it is clarified that the peak corresponds with low wind speed during the
measurement period.
• However, the other situations in the plot show very low line THD which
comply with the IEC.
43. • Plot (28) is the diurnal pattern of the mean and maximum values of
the line current THD, the plot shows that the line current THD
follows load pattern except for the situation of low wind speed.
• The plot corresponds with the diurnal line current plot (Plot 12), i.e.
maximum current THD occurred at minimum line current.
44. Consumed Reactive power
• Plot (29) is the statistical data as 10-minute average values of the consumed
reactive power by the wind turbines. The mean value of the consumed
reactive power is 17.22 kVAr during the measurement period.
45. • Plot (30) is the diurnal pattern of the mean, maximum and minimum
values of the consumed reactive power.
• The plot is the typical consumed reactive power profile since the graph
is the average values of the measurements period.
46. • Plot (31) is the statistical data of the reactive power consumption as a
function of active power production, the plot shows that the reactive power
varies proportionally to the active power, even though the values are
scattered when the active power is high.
• The vague correlation between active and reactive power on day 7/9/2005
still needs for an interpretation, the consumed reactive power on that day
looks higher than the active power.
47. • Plot (32) is the diurnal pattern of the consumed reactive power and the
active power as mean value, the plot shows that the reactive power varies
proportionally to the active power.
48. • Plot (33) is the diurnal pattern of the consumed reactive power and active
power as mean value.
• The plot shows that the reactive power varies proportionally to the active
power.
49. • Plot (34) is the statistical data of the reactive power consumption as a
function of active power production, the plot shows that the reactive power
varies proportionally to the active power, even though the values are
scattered when the active power is high.
• The vague correlation between active and reactive power on day 7/9/2005
still needs for an interpretation, the consumed reactive power on that day
looks higher than the active power.
50. • Plot (34) is the diurnal pattern of the power factor and active power as mean
value, the plot shows that the power factor decreases for increasing the
active power.
51. Produced Active Power
• Plot (35) is the statistical data as 10-minute average of the output active
power from the wind turbines, from the plot it is seen that the average
value of the output active power is 42.12 MW during the measurement
period, the plot corresponds with the line current plot (Plot 11).
52. • Plot (36) is the absolute value of the frequency distribution of statistical
data as 10–minute average of the output active power from the wind
turbines.
• The distribution has a tail towards low production as well as the output
active power varies from Zero MW to 55.06 MW as mean value and the
majority of high active power data represent more than 60 % of the full
data.
53. • Plot (37) is the diurnal pattern of the mean, maximum and minimum of the
active power value. The maximum value looks constant meanwhile the
minimum value is somewhat does not show any particular features. The plot
corresponds with the diurnal line current profile plot (Plot 12).
54. • Plot (38) is the diurnal pattern of the active power and wind speed as
mean value, it is observed that the wind speed is rather high during the
measurement period.
55. • Plot (39) is the statistical data as 10-minute average values and the
binned data (interval of 0.5 m/s) of the mean active power (uncorrected
power curves).
56. Capacity Factor
• Plot (40) is the statistical data of the capacity factor (CF) as 10-minute
average values, the average capacity factor during the measurement
period is 64.94 %, which is quite high.
57. • Plot (41) is the absolute value of the frequency distribution of statistical
data as 10–minute average of the capacity factor, the capacity factor
varies from zero to 85 % as mean value, and the majority of high values of
CF represent more than 60 % of the full data.
58. Conclusions
• During the measurement period the voltage level at Zafarana substation was
between 21.06 kV and 22.73 kV, or in other words 22 kV +3.3 % and – 4.27
%, International standard IEC (Ref 3) specifies that the voltage level should
be within ± 5 % of its nominal value measured as 10-minute average data or
± 10 % of its measured instantaneous values. From the results obtained it
could be stated that the voltage level when reaches to its maximum value
still within the required limit, meanwhile it is critical when reaches to its
minimum value.
• The voltage level at substation (point of connection of the wind turbines to
the grid) depends on the output power from the wind turbines.
59. • The absolute value of the voltage changes lays in a narrow range and
non-symmetrical around the nominal value, considering the wind farm
connected to the 220 kV national grid.
• The maximum value of phase No.2 is 13.40 kV (12.7 kV + 5.50 % ) and
minimum value of phase No.3 is 11.98 kV (12.7 kV -5.70 % ) , the two
voltage limits are out of range.
• During the measurement period, the grid frequency was between 49.86
Hz and 50.13 Hz being within the required limits to comply with
international standards on supply voltage characteristics.
60. • The load factor (mean / max ) is 96 % which is quite reasonable.
• During the measurement period, the measured total harmonic distortion
THD of the voltage on day 7/9/2005 reached to 3.11% being within the
required limit to comply with international standards on supply voltage
characteristics.
• The total harmonic distortion in voltage is not due to the output power
from the wind turbines, but follows the daily load pattern.
• No correspondence between harmonic amplitude and overall power
output level.
• Fixed-speed wind turbines do not produce any harmonics; meanwhile
variable-speed wind turbines may be produce different amounts and
orders of harmonics depending on the type of inverter used.
61. • The maximum current THD occurred at minimum line current.
• The reactive power consumption of the wind farm increases for
increasing output power.
• The maximum value of the power factor is 0.99 at output power 4.41
MW.
•
• The average capacity factor of the wind farm is 64.9 % during the
measurement period.
• The majority of high active power data represent more than 60 % of the
full data.
• The average wind speed throughout the measurement period is 12.69
m/s.
62. Recommendations
• In case of adding more wind turbines, a through analysis must be
executed, in particular voltage level.
• The measurements regarding power fluctuations, flicker, and transient
phenomena should be fulfilled in case of promoting measurements
instruments.