Engineering Commons^™

Herramienta Computacional Para El Análisis De Señales En Sistemas De Potencia Con Alta Penetración De Fuentes No Convencionales De Energía, Johinner Mauricio Sanabria Villamizar

Ingeniería Eléctrica

El uso de las Fuentes de Generación de Energía Renovable presenta nuevos desafíos relacionados con problemas de calidad de energía, como la estabilidad del voltaje y la frecuencia. En busca de solucionar este desafío, se desarrolla e implementa la metodología para el análisis de señales en sistemas de potencia que involucran fuentes de energía renovables no convencionales. La metodología mostrada implica la aplicación de la transformada de Hilbert-Huang, apoyado en la descomposición empírica modal (EMD) para descomponer la señal armónica en sus modos intrínsecos modales (IMF). Además, se desarrolla un método combinado para la evaluación de las perturbaciones de la …

Advanced Digital Signal Processing Based Redefined Power Quality Indices, And Their Applications To Wind Power, Md Moinul Islam

Theses and Dissertations

This dissertation proposes a time-frequency distribution (TFD) based new method to redefine the power quality (PQ) indices for the assessment of PQ disturbances typically present in electric power systems. The redefined PQ indices are applied to various types of synthetic and real-world PQ disturbances in order to verify the efficacy and applicability of the proposed method. The case studies show that the proposed method provides actual results with respect to the existing TFD-based transient PQ indices, and provides much more accurate results than the traditional fast Fourier transform (FFT) based PQ indices under stationary and nonstationary PQ disturbances. In addition, …

Integration Of Upqc For Power Quality Improvement In Distributed Generation Network – A Review, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon

Dr. Shafiuzzaman Khan Khadem

In this paper a technical review of the integration of a Unified Power Quality Conditioner (UPQC) in a distributed generation network is presented. Although the primary task of UPQC is to minimize grid voltage and load current disturbances along with reactive and harmonic power compensation, additional functionalities such as compensation of voltage interruption and active power transfer to the load and grid have also been identified. Connection methodologies with their advantages and disadvantages are also described. Recent improvements in capacity expansion techniques and future trends for the application of UPQC in distributed modes are also identified.

Power Quality In Grid Connected Renewable Energy Systems: Role Of Custom Power Devices, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon

Dr. Shafiuzzaman Khan Khadem

This paper deals with the technical review of power quality problems associated with the renewable based distributed generation systems and how the custom power devices like STATCOM, DVR and UPQC play important role in power quality improvement. IEEE and IEC standard for the grid connected renewable energy systems are one of the critical point of interest for the selection of custom power devices. Special attention has been given on the compensation of reactive power, harmonic current and voltage fluctuation during the interconnected as well as islanding mode of operation. As the solar and wind are the most abundant resources therefore …

Identify The Exact Location Of Voltage Sag Source, Asadollah Kazemi

Dr. ASADOLLAH KAZEMI

No abstract provided.

Resource-Induced Voltage Flicker For Wave Energy Converters – Assessment Tools, Fergus Sharkey, Joe Macenri, Elva Bannon, Michael Conlon, Kevin Gaughan

Articles

For wave energy converters, the input resource has a typical period of 5–20 s depending on the site location and dominant seastates. Wave energy converters generally produce mechanical power twice per wave cycle and therefore depending on the storage available, the electrical power output has half the period of the input resource. These regular power changes induce a voltage change at the point of connection (POC) which is proportional to the amplitude of the power change and at the same frequency. Therefore the coupling of the input resource to the output power of a wave energy converter will cause voltage …

Modeling, Analyses And Assessment Of Microgrids Considering High Renewable Energy Penetration, Qiang Fu

Theses and Dissertations

Microgrids are receiving attention due to the increasing need to integrate distributed generations and to ensure power quality and provide energy surety to the customers. Since renewables need to be in the mix for energy surety, a high renewable-energy penetrated microgrid is analyzed in this paper. The standard IEEE 34 bus distribution feeder is adapted and managed as a microgrid by adding distributed generation and load profiles. The 25kV system parameters are scaled down to 12kV and renewable sources including solar PV and wind turbines, an energy storage system, and a natural gas generator have been added to the 34-bus …

Microgrid Power Quality Analysis, Nikolai Kempcatala, Daniel Pleau, Scott Clemons

Electrical Engineering

The microgrid power quality analysis senior project addresses power quality assessment. Our senior project uses the PowerSight 3000 power measurement tool to record and analyze various electrical measurements including voltage, current, power, power factor, harmonics and AC frequency.

Our project will analyze power quality issues that result from switching from the utility grid to a smart grid run on primarily photovoltaic distributed generation. In the event of a utility failure, the smart grid can serve as an isolated grid for the system, this is called islanded mode. Our project assesses the reliability of operation in islanded mode. Our analysis should …

Voltage Flicker Evaluation For Wave Energy Converters – Assessment Guidelines, Fergus Sharkey, Elva Bannon, Joe Macenri, Kevin Gaughan, Michael Conlon

Conference papers

Voltage flicker is a power quality problem caused by regularly oscillating active and reactive power either from a load or generator. The regular power oscillations induce a voltage change at the grid connection which is proportional to the amplitude of the power oscillation and at the same frequency. The impedance of the grid (grid strength) at the point of connection is a factor in the amplitude of the voltage oscillation. The frequency band of interest for flicker evaluation is from 0.01-20Hz, and is most severe at 8.8Hz. The frequency of the primary resource for wave energy converters lies within this …

Analysis Of Compensation Techniques Applied To The Control Of Converter Connected Synchronous Wind Turbines And Dfig’S During Grid Disturbances., Joseph Kearney, Michael Conlon, Eugene Coyle

Conference papers

This paper investigates control schemes to improve the performance of converter connected synchronous generators and DFIG’s to grid voltage unbalance and grid faults. Both the synchronous generator with a full converter and a DFIG are modelled in Matlab/Simulink. The control schemes of both turbines are modified to improve their performance during grid disturbances including grid voltage unbalance and single-phase faults. These disturbances are introduced into the models at specific times to analyse the performance of the wind generation systems. The performances of both systems to the grid disturbances are compared and the results are analysed.

Integration Of Upqc For Power Quality Improvement In Distributed Generation Network – A Review, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon

Conference Papers

In this paper a technical review of the integration of a Unified Power Quality Conditioner (UPQC) in a distributed generation network is presented. Although the primary task of UPQC is to minimize grid voltage and load current disturbances along with reactive and harmonic power compensation, additional functionalities such as compensation of voltage interruption and active power transfer to the load and grid have also been identified. Connection methodologies with their advantages and disadvantages are also described. Recent improvements in capacity expansion techniques and future trends for the application of UPQC in distributed modes are also identified.

Analysis Of Converter Connected Synchronous Wind Turbines To Grid Disturbances., Joseph Kearney, Michael Conlon, Eugene Coyle

Conference papers

This paper investigates the performance of synchronous generators to grid voltage unbalance and grid faults. A Model of a synchronous generator with a full converter is implemented in the SimPowerSystems toolbox in Matlab/Simulink. Methods to modify the converter control schemes to improve the synchronous generator systems response to grid voltage unbalance and grid faults are investigated. Grid faults including grid voltage unbalance, and line-to-ground faults are introduced into the model at specific times to analyse the performance of the wind generation system. Improvements in the performance of the synchronous generator WECS to the grid disturbances are illustrated.

A Review Of Parallel Operation Of Active Power Filters In The Distributed Generation System, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon

Conference papers

In this paper a technical review of parallel operation of Active Power Filter (APF) for harmonic power compensation in distributed generation (DG) network has been presented. Controlling methods and connection topologies with their pros and cons are described. Recent improvements in controlling and future trends for the application of APFs in distributed mode are also identified.

Capacitor Switching Transient Modeling And Analysis On An Electrical Utility Distribution System Using Simulink Software, Durga Bhavani Mupparty

University of Kentucky Master's Theses

The quality of electric power has been a constant topic of study, mainly because inherent problems to it can bring great economic losses in industrial processes. Among the factors that affect power quality, those related to transients originated from capacitor bank switching in the primary distribution systems must be highlighted. In this thesis, the characteristics of the transients resulting from the switching of utility capacitor banks are analyzed, as well as factors that influence there intensities. A practical application of synchronous closing to reduce capacitor bank switching transients is presented. A model that represents a real distribution system 12.47kV from …

Dynamic Voltage Restorer (Dvr) For Voltage Sag Mitigation, Tarek Ibrahim Elshennawy, Amr Yehia Abou-Ghazala A. Prof., Mahmoud El-Gammal Prof.

Tarek Ibrahim ElShennawy

The Dynamic Voltage Restorer (DVR) is fast, flexible and efficient solution to voltage sag problem. The DVR is a power electronic based device that provides three-phase controllable voltage source, whose voltage vector (magnitude and angle) adds to the source voltage during sag event, to restore the load voltage to pre-sag conditions. The DVR is designed for protecting the whole plant with loads in the range of some MVA. The DVR can restore the load voltage within few milliseconds. Several configurations and control methods are proposed for the DVR. In this paper, an overview of the DVR, its functions, configurations, components, …

The Application Of Multi Frequency Resonant Controllers In In A Dfig To Improve Performance By Reducing Unwanted Power And Torque Pulsations And Reducing Current Harmonics., Joseph Kearney, Michael Conlon, Eugene Coyle

Conference papers

The paper describes a method to control the rotor-side and grid side converters in a DFIG when subjected to the effects of network voltage unbalance conditions. Multi Frequency Resonant Controllers are incorporated into the grid side and rotor side converters to assist in the control functions. The Resonant Controllers are tuned to twice the network frequency to assist in the control of power and torque pulsations and to three times the network frequency to assist in the control of the generated third harmonic currents. A DFIG model is implemented in Matlab/Simulink and simulations show the reduction in power and torque …

The Application Of Multi Frequency Resonant Controllers In In A Dfig To Improve Performance By Reducing Unwanted Power And Torque Pulsations And Reducing Current Harmonics., Joseph Kearney, Michael Conlon, Eugene Coyle

Conference papers

The paper describes a method to control the rotor-side and grid side converters in a DFIG when subjected to the effects of network voltage unbalance conditions. Multi Frequency Resonant Controllers are incorporated into the grid side and rotor side converters to assist in the control functions. The Resonant Controllers are tuned to twice the network frequency to assist in the control of power and torque pulsations and to three times the network frequency to assist in the control of the generated third harmonic currents. A DFIG model is implemented in Matlab/Simulink and simulations show the reduction in power and torque …

Design Of A Conditioner For Smoothing Wind Turbine Output Power, Murali Bottu, Mariesa Crow, A. Curt Elmore

Electrical and Computer Engineering Faculty Research & Creative Works

As a result of wind speed intermittency, highly variable wind power output can adversely impact local loads. We propose a conditioner to smooth the variable wind power by utilizing the energy of an ultracapacitor. The conditioner is based on a single phase voltage source inverter (VSI) connected between the grid interconnection point and the ultracapacitor. The shunt VSI injects or absorbs active power from the line to smooth the wind power by utilizing the short term storage capabilities of the ultracapacitor. The ultracapacitor is connected to the DC link through a DC-DC converter, which maintains the voltage of the DC …

Software Algorithms To Coordinate And Improve Voltage Sag Ridethrough Capabilities Of Networked Industrial Processes, Owen Parks

All Dissertations

For those who design, operate, and troubleshoot industrial processes, electric power quality is a subject that requires much consideration. Processes that use electronic sensors, actuators, and computation devices are heavily reliant on a stable, consistent input power source. When a power quality event such as a voltage fluctuation occurs, automation equipment often behaves unpredictably and causes process malfunction or failure.
Because industrial power consumers often blame their electric utility for these events, some utilities offer process susceptibility studies as a service for their customers. During a typical study, utility technicians and engineers perform in-house tests on suspect components or systems …

Power Quality In Grid Connected Renewable Energy Systems: Role Of Custom Power Devices, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon

Conference papers

This paper deals with the technical review of power quality problems associated with the renewable based distributed generation systems and how the custom power devices like STATCOM, DVR and UPQC play important role in power quality improvement. IEEE and IEC standard for the grid connected renewable energy systems are one of the critical point of interest for the selection of custom power devices. Special attention has been given on the compensation of reactive power, harmonic current and voltage fluctuation during the interconnected as well as islanding mode of operation. As the solar and wind are the most abundant resources therefore …

The Control Of Rotor Side And Grid Side Converters In A Dfig During Network Voltage Unbalance Conditions Using Resonant Current Controllers., Joseph Kearney, Michael Conlon, Eugene Coyle

Conference papers

This paper implements control techniques to enable improved operation of DFIG’s when subjected to the effects of network voltage unbalance conditions. The control scheme involves the integration of a resonant regulator into the PI controllers of both the rotor side and grid side converters in a DFIG. The resonant controller is tuned to twice the network frequency (2ω_e) and designed to mitigate against the oscillations in a DFIG due to network voltage unbalance conditions. The grid side converter controller also incorporates a second resonant controller tuned to three times the grid frequency (3ω_e) to alleviate the …

The Integrated Control Of The Rotor Side And Grid Side Converters In A Dfig To Reduce Both Power And Torque Pulsations During Network Voltage Unbalance Conditions., Joseph Kearney, Michael Conlon, Eugene Coyle

Conference papers

No abstract provided.

Real Time Implementation Of An Artificial Immune System Based Controller For A Dstatcom In An Electric Ship Power System, Pinaki Mitra, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

A new adaptive control strategy based on artificial immune system (AIS) for a DSTATCOM in an electric ship power system is presented in this paper. DSTATCOM is a shunt compensation device, which can be used to improve the power quality during the pulse power requirements in a naval shipboard system. The role of DSTATCOM controller is very important to meet this objective. In this paper, the DSTATCOM controller parameters are first tuned by particle swarm optimization (PSO) technique, so that it can provide innate immunity to common system disturbances. Then, these optimum parameters are modified online by an artificial immune …

Intelligent Tool For Determining The True Harmonic Current Contribution Of A Customer In A Power Distribution Network, Joy Mazumdar, Ronald G. Harley, Frank C. Lambert, Ganesh K. Venayagamoorthy, Marty L. Page

Electrical and Computer Engineering Faculty Research & Creative Works

Customer loads connected to power distribution network may be broadly categorized as either linear or nonlinear. Nonlinear loads inject harmonics into the power network. Harmonics in a power system are classified as either load harmonics or as supply harmonics depending on their origin. The source impedance also impacts the harmonic current flowing in the network. Hence, any change in the source impedance is reflected in the harmonic spectrum of the current. This paper proposes a novel method based on artificial neural networks to isolate and evaluate the impact of the source impedance change without disrupting the operation of any load, …

The Role Of Micro Wind Generation In Ireland’S Energy Future, Keith Sunderland, Michael Conlon

Conference papers

This paper defines the current position for micro-generation, with particular reference to the potential for micro-wind units, in the Irish electricity supply system. A network model is developed using the Distflow method of load flow analysis and is applied to consider the appropriate level of micro-generation penetration.

A Comparison Of Linear And Nonlinear Statcom Control For Power Quality Enhancement, Atousa Yazdani, Mariesa Crow, Jianjun Guo

Electrical and Computer Engineering Faculty Research & Creative Works

This paper introduces a multilevel STATCOM for electric arc furnace power quality enhancement. An eleven level cascaded multilevel converter is used to alleviate the impacts of an unbalanced arc furnace load. The STATCOM provides a power electronic-based means of embedded control for reactive power support.

Analysis Of A Variable Speed Double-Fed Induction Generator Wind Turbine During Network Voltage Unbalance Conditions., Joseph Kearney, Michael Conlon

Conference papers

The behaviour of Double-Fed Induction Generators to supply network voltage unbalance is investigated. The paper shows the effects that voltage unbalance can have on a DFIG, using Matlab/Simulink. The results from simulations show that voltage unbalance affects both the induction generator and the rotor converter, due to the high unbalanced currents generated. The ability to modify the control strategy of a DFIG to compensate for voltage unbalance is outlined and simulations show the improvements to the performance of the DFIG.

Change In Voltage Distortion Predictions At The Pcc Due To Changing Nonlinear Load Current Profile Using Plant Startup Data, Joy Mazumdar, Frank C. Lambert, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

Customer loads connected to electricity supply systems may be broadly categorized as either linear or nonlinear. Nonlinear loads inject harmonics in a power distribution network. The interaction of the nonlinear load harmonics with the network impedances creates voltage distortions at the point of common coupling (PCC) which in turn affects other loads connected to the same PCC. When several nonlinear loads are connected to the PCC, it is difficult to predict mathematically how each nonlinear load is affecting the voltage distortion level at the PCC. Typically, customers with nonlinear loads apply harmonic filtering techniques to clean up their current and …

Performance Of A Variable Speed Double-Fed Induction Generator Wind Turbine During Network Voltage Unbalance Conditions, Joseph Kearney, Michael Conlon

Conference papers

The issues of the negative performance of DFIG’s due to supply network voltage unbalance are outlined in this paper. The paper shows the effects that voltage unbalance can have on a DFIG, using the power simulation program DigSilent. The results from simulations show that voltage unbalance affects the both the induction generator and the rotor converter, due to the high unbalanced currents generated. The ability to modify the control strategy of a DFIG to compensate for voltage unbalance is outlined and a proposal to build a test-rig suitable to implement such a system is suggested.

Overdistention Operation Of Cascaded Multilevel Inverters, Xiaomin Kou, Keith Corzine, M. W. Wielebski

Electrical and Computer Engineering Faculty Research & Creative Works

In the past decade, the multilevel power converter has transitioned from an experimental concept to a standard product of many medium-voltage drive manufacturers. By utilizing small voltage steps, the multilevel topology offers higher power quality, higher voltage capability, lower switching losses, and improved electromagnetic compatibility over standard topologies. Recently, several researchers have focused on the cascaded multilevel inverter whereby two multilevel inverters are series connected to a motor load by splitting the neutral connection. The resulting performance is exceptional in terms of power quality since the overall number of voltage levels is effectively the product of the two cascaded inverters. …