This document presents the small-signal AC modeling and closed-loop control of a three-phase interleaved boost converter. It begins with an introduction to boost converters and motivates the use of multiphase interleaved topologies. It then describes the development of a state-space averaged model for the three-phase converter by identifying the different circuit states over a switching period and deriving the corresponding state equations. These are then linearized around an operating point to obtain the small-signal AC model. Finally, it discusses the use of a Type III compensator in the closed-loop control system to improve frequency response and regulate the output voltage under load variations.
Simulation of 3 Phase to 3 Phase Power Conversion Using Matrix Converter with...IJERA Editor
This paper proposes a new approach of design and implementation of 3 phase to 3 phase conversion using
matrix converter. It includes the design, modeling and implementation. The entire matrix converter circuits are
developed by mathematical model so as to reduce computational time and performances of the converter are
evaluated using MATLAB/SIMULINK for RL Load. The mathematical expressions relating the input and
output of the three phase matrix converter are implemented by using simulink block set. The duty cycles of the
matrix converter bidirectional switches are calculated using modified venturini algorithm for maximum (0.866)
and minimum (0.5) voltage transfer ratio.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
A NOVEL TCHNOLOGY FOR HARMONICS AND UNBALANCE COMPENSATION IN ELECTRIC TRACTI...ijiert bestjournal
Power quality problems in power systems have been i mproved due to nonlinear loads. To compensate these problems Direct Power Compensator was proposed in this paper. A Direct Power Compensator (DPC) is proposed in this paper to elim inate the harmonic currents,compensate power factor and voltage unbalance problems created by th e nonlinear loads present in three phase systems. A DPC contains back to back converter by sharing th e same dc link power and v/v transformer to provide a voltage balance in transmission line. Hys teresis harmonic current regulator is used to produce pulse for back to back converter. A control ler maintains the dc-link voltage and compensates the power factor,harmonic currents. A comparative analysis for traction system with and without DPC was performed using MATLAB Simulink . Simulation results show the controller advantages and the applicability of the proposed me thod in railway systems.
1 ijaems oct-2015-3-design and development of novel matrix converter performanceINFOGAIN PUBLICATION
Matrix converter is a direct AC-AC converter topology that directly converts energy from an AC source to an AC load without the need of a bulky and limited lifetime energy storage element. Due to the significant advantages offered by matrix converter, such as adjustable power factor, capability of regeneration and high quality sinusoidal input/output waveforms. Matrix converter has been one of the AC–AC topologies that hasreceived extensive research attention for being an alternative to replace traditional AC-DC-AC converters in the variable voltage and variable frequency AC drive applications. In the present paper an indirect space vector modulated matrix converter is proposed. The basic idea of an indirect modulation scheme is to separately apply SVM to the rectification and inversion stages, before combining their switching states to produce the final gating signals. The paper encompasses development of a laboratory prototype of 230V, 250VA three phase to three phase DSP controlled matrix converter fed induction motor drive. The observations and real time testings have been carried out to evaluate and improve the stability of system under various typical abnormal input voltage conditions
Simulation of 3 Phase to 3 Phase Power Conversion Using Matrix Converter with...IJERA Editor
This paper proposes a new approach of design and implementation of 3 phase to 3 phase conversion using
matrix converter. It includes the design, modeling and implementation. The entire matrix converter circuits are
developed by mathematical model so as to reduce computational time and performances of the converter are
evaluated using MATLAB/SIMULINK for RL Load. The mathematical expressions relating the input and
output of the three phase matrix converter are implemented by using simulink block set. The duty cycles of the
matrix converter bidirectional switches are calculated using modified venturini algorithm for maximum (0.866)
and minimum (0.5) voltage transfer ratio.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
A NOVEL TCHNOLOGY FOR HARMONICS AND UNBALANCE COMPENSATION IN ELECTRIC TRACTI...ijiert bestjournal
Power quality problems in power systems have been i mproved due to nonlinear loads. To compensate these problems Direct Power Compensator was proposed in this paper. A Direct Power Compensator (DPC) is proposed in this paper to elim inate the harmonic currents,compensate power factor and voltage unbalance problems created by th e nonlinear loads present in three phase systems. A DPC contains back to back converter by sharing th e same dc link power and v/v transformer to provide a voltage balance in transmission line. Hys teresis harmonic current regulator is used to produce pulse for back to back converter. A control ler maintains the dc-link voltage and compensates the power factor,harmonic currents. A comparative analysis for traction system with and without DPC was performed using MATLAB Simulink . Simulation results show the controller advantages and the applicability of the proposed me thod in railway systems.
1 ijaems oct-2015-3-design and development of novel matrix converter performanceINFOGAIN PUBLICATION
Matrix converter is a direct AC-AC converter topology that directly converts energy from an AC source to an AC load without the need of a bulky and limited lifetime energy storage element. Due to the significant advantages offered by matrix converter, such as adjustable power factor, capability of regeneration and high quality sinusoidal input/output waveforms. Matrix converter has been one of the AC–AC topologies that hasreceived extensive research attention for being an alternative to replace traditional AC-DC-AC converters in the variable voltage and variable frequency AC drive applications. In the present paper an indirect space vector modulated matrix converter is proposed. The basic idea of an indirect modulation scheme is to separately apply SVM to the rectification and inversion stages, before combining their switching states to produce the final gating signals. The paper encompasses development of a laboratory prototype of 230V, 250VA three phase to three phase DSP controlled matrix converter fed induction motor drive. The observations and real time testings have been carried out to evaluate and improve the stability of system under various typical abnormal input voltage conditions
Optimal Placement of Static Series Voltage Regulator (SSVR) in Distribution S...IJERA Editor
This paper presents optimal placement of Static Series Voltage Regulator (SSVR), for voltage profile improvement and power loss reduction in radial distribution systems under steady state condition. SSVR consists of a series compensator. The series compensator injects the series voltage in quadrature with the branch current in such a way that the receiving end voltage is maintained at desired value (up to 1 p.u). The criteria for selection of optimum location of SSVR are under voltage problem mitigation and loss reduction in the network under steady sate condition. Particle Swam Optimization (PSO) technique is used to find the rating of the device. The proposed model is tested using standard distribution system consisting of 33 nodes
The high penetration of power electronic based distributed energy resources (DERs) has increased the importance and attention given to voltage security of distribution systems. Voltage control in the electrical power system is critical for a proper operating condition. Therefore, distribution systems must have the ability to maintain a secure voltage profile. Using inverters for Volt/VAR control (VVC) can provide a faster response for voltage regulation than traditional voltage regulation devices, such as transformer load tap changers and voltage regulators. The primary objective of this paper is to demonstrate how smart inverters can be used to eliminate the voltage deviation by solving a mixed-integer quadratic program to determine the amount of reactive power that should be injected or absorbed at the appropriate nodes. The proposed method incorporates capacitor banks connected to the network and determines whether to turn on or off the capacitor bank for voltage regulation. These processes will be demonstrated in several cases that are focused on mitigating voltage-dips and swells.
New Dead-Time Compensation Method of Power Inverter Using Carrier Based Sinus...IJECEIAES
A new dead-time compensation method of power inverter circuits is suggested and presented in this paper. The proposed method utilizes carrier based sinusoidal pulse width modulation technique to produce driving signals of the inverter power switches with dead-time correction capability. The proposed method able to eliminate dead-time effects such as reducing the waveform distortion of the inverter output current, and increasing the fundamental component amplitude of output current. An analysis of the proposed method is presented. Some computer simulations were carried out to investigate the principle operation, and to test performance of the new method. The developed method was validated through experimental test of H-bridge voltage source inverter circuits. The data obtained from the computer simulation and prototype experiments have confirmed that that the proposed method worked well compensating the dead-time in the voltage source power inverter circuits.
A Comparison Between Two Average Modelling Techniques of AC-AC Power ConvertersIAES-IJPEDS
In this paper, a comparative evaluation of two modelling tools for switching AC-AC power converters is presented. Both of them are based on average modelling techniques. The first approach is based on the circuit averaging technique and consists in the topological manipulations, applied to a converter states. The second approach makes use of a state-space averaged model of the converter and is based on analytical manipulations using the different state representations of a converter. The two modelling techniques are applied to a same AC-AC called matrix-reactance frequency converter based on buck-boost topology. These techniques are compared on the basis of their rapidity, quantity of calculations and transformations and its limitations.
This paper focuses on Power Loss estimation in
Electrical Sub Transmission and Distribution systems. The
earliest empirical approaches were by Buller and Woodrow in
1928, Hoebel in 1959, M.W. Gustafson from 1983 to 1993.
Gustafson changed the values of the coefficients and provided
them with a constant loss term. It has been observed that this
approach is not suitable for the present load scenario. In this
paper, its successive approach has been proposed and tested
with real time data. It has been concluded that the relationship
between loss factor and load factor is not as complicated as
perceived but easily understandable. By using exponential
curve fitting, a relationship that is very close to reality can be
obtained. To verify the obtained equation, data has been
collected from a 33kV sub transmission line existing between
132kV/33kV Thurkayamjal substation and 33kV/11kV
Hayathnagar substation, APTRANSCO, Andhra Pradesh.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Enhancement of upfc performance with matrix converter using advanced direct p...eSAT Journals
Abstract In this paper presents a direct power control (DPC) for three-phase matrix converters operating as unified power flow controllers (UPFCs). Matrix converters (MCs) allow the direct ac/ac power conversion without dc energy storage links; therefore, the MC-based UPFC (MC-UPFC) has reduced size and cost, reduced capacitor power losses, together with higher reliability. Theoretical principles of direct power control (DPC) based on sliding mode control methods are established for an MC-UPFC dynamic model including the input filter. As a result, line active and reactive power, together with ac supply reactive power, can be directly controlled by selecting an appropriate matrix converter switching state assuring good steady-state and dynamic responses. Experimental results of DPC controllers for MC-UPFC show decoupled active and reactive power control, zero steady-state tracking error, and fast response times. Compared to an MC-UPFC using active and reactive power linear controllers based on a modified Venturini high-frequency PWM modulator, the experimental results of the advanced DPC-MC guarantee faster responses without overshoot and no steady-state error, presenting no cross-coupling in dynamic and steady-state responses. Keywords: Ac/ac conversion advanced direct power controller, matrix converter, unified power flow controller.
A Novel Approach for Allocation of Optimal Capacitor and Distributed Generati...paperpublications3
Abstract: Distributed generation (DG) units, based on their interfacing technology are divided into synchronous generator interfaced DGs, asynchronous generator interfaced DGs and inverter interfaced DGs. This paper presents two algorithms for allocation of optimal capacitor and distributed generation on radial distribution system. These algorithms predict requirement of reactive vars and real power and supplied via capacitor banks and distributed generation. This arrangement reduces transmission losses and voltage stability problem. Developed algorithm has been implemented on two IEEE 69 nodes and 52 nodes systems.
The paper describes the single stage AC-AC converter. This converter is a good alternative to quasi direct back to back converter. This single stage converter is called Matrix Converter. Matrix converter is an array of controlled semiconductor switches that connects three phase source to the three phase load. This converter provides bidirectional power flow, sinusoidal input and output waveforms and they have no dc link storage elements. Simulation model and results presented showing Venturini control method of matrix converter.
Development of a Novel Three Phase Grid-Tied Multilevel Inverter TopologyIAES-IJPEDS
The conventional line-commutated ac-to-dc converters/ inverters have square-shaped line current. It contains higher-order harmonics which generates EMI and it causes more heating of the core of distribution or power transformers. PWM based inverters using MOSFET/IGBT have higher switching losses, and the power handling capability and reliability are quite low in comparison to thyristors/ SCR. A thyristor based forced commutated inverters are not suitable for PWM applications due to the problems of commutation circuits. A pure sinusoidal voltage output or waveform with low harmonic contents is most desirable for ac load using dc to ac conversion. This paper presents a new multilevel inverter topology in which three phase ac- to-dc converter circuits are used in inversion mode by controlling the switching angle. Due to natural commutation, no separate circuit is required for synchronization. In this paper simulation and analysis are done for grid-tied three-phase 6-pulse, Two three-phase, 3-pulse and 12-pulse converter. These converters are analysed for different battery voltage and different switching angle combinations in order to reduce the total harmonic distortion (THD). Three-phase harmonic filters are further added to the grid side to reduce the harmonic content in the line current. A comparative study of these converters is also presented in this paper.
This paper presents the control for Shunt Active Power (SAPF) filter in photovoltaic (PV) systems connected to the grid. The proposed configuration of the system consists of a photovoltaic array that connected to the grid through the three-phase inverter topology that also serves as an active filter. Photovoltaic is coupled in parallel with the direct curret (DC) side of the active filter. With this configuration, can be obtained three advantages, namely the elimination of harmonic currents caused by nonlinear load, reactive power injection, and injection of active power generated photovoltaic. The p-q Theory is used to calculate the harmonic reference current to be used to control the active filter coupled fotovoltaic in generating anti-harmonic currents. The results show that system can reduce harmonic distortion from THD 27.22% to be THD 1.05%, whereas when the active power from photovoltaic injected, the THD become 2.01%. Power sharing can also be seen from this study.
Algorithm for Fault Location and Classification on Parallel Transmission Line...IJECEIAES
This paper proposed a new algorithm for fault location and classification using wavelet based on Clarke’s transformation to obtain the fault current. This novel method of fault current approach is studied by comparing the use of the glide path of the fault voltage. The current alpha and beta (Current Mode) were used to transform the signal using discrete wavelet transform (DWT). The fault location was determined by using the Clarke’s transformation, and then turned into a wavelet, which was very precise and thorough. The most accurate was the mother wavelet Db4 which had the fastest time and smallest error detection when compared with the other wavelet mothers. In this study, the Clarke’s transformation is also compared with the Karenbauer’s, which has produced results with similar error percentage. The simulation results using PSCAD / EMTDC software showed that the proposed algorithm could distinguish internal and external faults to get the current signal in the transformation of a signal fault.
Neural Network based p-q-r Theory for Harmonic Reduction and Neutral Current ...IJECEIAES
The power quality compensator chosen in this paper is a DSTATCOM which integrates a three phase four leg Voltage Source Converter (VSC) with a DC capacitor. The major role of the DSTATCOM is to mitigate the components of harmonic/reactive current present in the line current thereby shapes the grid current to be sinusoidal and improves the power factor nearly unity under varying conditions. In addition DSATATCOM mitigates neutral current (I ) and balances the load currents under unbalanced conditions in three phase four wire (3P4W) distribution system. The control strategy proposed for the DSTATCOM is a Neural Network (NN) based p-q-r theory with two Artificial Neural Network (ANN) controllers for a 3P4W distribution system. The reference signal for 3P3W Shunt Active Power Filter (SAPF) is calculated by implementing an ANN controller. The alleviation of I sn under unbalanced condition is achieved by another ANN controller which produces reference signal for the 1Φ APF. The performance of the proposed DSTATCOM is analysed for various conditions through simulations in MATLAB SIMULINK and the simulation results justify the effectiveness of the propounded NN based control algorithm for DSTATCOM. sn
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
In this paper, a Wavelet modulated isolated two-stage three-phase bidirectional AC-DC converter is proposed for electric vehicle (EV) charging systems. Half-bridge resonant CLLC converter is proposed due to its high efficiency, wide gain range, galvanic isolation and bidirectional power flow. Wavelet modulation technique is used for three-phase six leg AC-DC converter due to its benefits of high DC component and lower harmonic contents. The proposed two-stage converter is developed and simulated in MATLAB Simulink environment. The contribution of this paper is on the implementation and performance analysis of Wavelet modulation in bidirectional AC-DC converters. The results show that Wavelet modulation is suitable to be implemented for the proposed bidirectional converter. The performance of the proposed converter delivers very low output voltage ripple and total harmonic distortion output current of less than 10% which is within the expected results.
State-space averaged modeling and transfer function derivation of DC-DC boost...TELKOMNIKA JOURNAL
This paper presents dynamic analysis of a boost type DC-DC converter for high-brightness LED (HBLED) driving applications. The steady state operation in presence of all system parasitics has been discussed for continuous conduction mode (CCM). The state-space averaging, energy conservation principle and standard linearization are used to derive ac small signal control to inductor current open-loop transfer function of the converter. The derived transfer function can be further used in designing a robust feed-back control network for the system. In the end frequency and transient responses of the derived transfer function are obtained for a given set of component values, hence to provide a useful guide for control design engineers.
Optimal Placement of Static Series Voltage Regulator (SSVR) in Distribution S...IJERA Editor
This paper presents optimal placement of Static Series Voltage Regulator (SSVR), for voltage profile improvement and power loss reduction in radial distribution systems under steady state condition. SSVR consists of a series compensator. The series compensator injects the series voltage in quadrature with the branch current in such a way that the receiving end voltage is maintained at desired value (up to 1 p.u). The criteria for selection of optimum location of SSVR are under voltage problem mitigation and loss reduction in the network under steady sate condition. Particle Swam Optimization (PSO) technique is used to find the rating of the device. The proposed model is tested using standard distribution system consisting of 33 nodes
The high penetration of power electronic based distributed energy resources (DERs) has increased the importance and attention given to voltage security of distribution systems. Voltage control in the electrical power system is critical for a proper operating condition. Therefore, distribution systems must have the ability to maintain a secure voltage profile. Using inverters for Volt/VAR control (VVC) can provide a faster response for voltage regulation than traditional voltage regulation devices, such as transformer load tap changers and voltage regulators. The primary objective of this paper is to demonstrate how smart inverters can be used to eliminate the voltage deviation by solving a mixed-integer quadratic program to determine the amount of reactive power that should be injected or absorbed at the appropriate nodes. The proposed method incorporates capacitor banks connected to the network and determines whether to turn on or off the capacitor bank for voltage regulation. These processes will be demonstrated in several cases that are focused on mitigating voltage-dips and swells.
New Dead-Time Compensation Method of Power Inverter Using Carrier Based Sinus...IJECEIAES
A new dead-time compensation method of power inverter circuits is suggested and presented in this paper. The proposed method utilizes carrier based sinusoidal pulse width modulation technique to produce driving signals of the inverter power switches with dead-time correction capability. The proposed method able to eliminate dead-time effects such as reducing the waveform distortion of the inverter output current, and increasing the fundamental component amplitude of output current. An analysis of the proposed method is presented. Some computer simulations were carried out to investigate the principle operation, and to test performance of the new method. The developed method was validated through experimental test of H-bridge voltage source inverter circuits. The data obtained from the computer simulation and prototype experiments have confirmed that that the proposed method worked well compensating the dead-time in the voltage source power inverter circuits.
A Comparison Between Two Average Modelling Techniques of AC-AC Power ConvertersIAES-IJPEDS
In this paper, a comparative evaluation of two modelling tools for switching AC-AC power converters is presented. Both of them are based on average modelling techniques. The first approach is based on the circuit averaging technique and consists in the topological manipulations, applied to a converter states. The second approach makes use of a state-space averaged model of the converter and is based on analytical manipulations using the different state representations of a converter. The two modelling techniques are applied to a same AC-AC called matrix-reactance frequency converter based on buck-boost topology. These techniques are compared on the basis of their rapidity, quantity of calculations and transformations and its limitations.
This paper focuses on Power Loss estimation in
Electrical Sub Transmission and Distribution systems. The
earliest empirical approaches were by Buller and Woodrow in
1928, Hoebel in 1959, M.W. Gustafson from 1983 to 1993.
Gustafson changed the values of the coefficients and provided
them with a constant loss term. It has been observed that this
approach is not suitable for the present load scenario. In this
paper, its successive approach has been proposed and tested
with real time data. It has been concluded that the relationship
between loss factor and load factor is not as complicated as
perceived but easily understandable. By using exponential
curve fitting, a relationship that is very close to reality can be
obtained. To verify the obtained equation, data has been
collected from a 33kV sub transmission line existing between
132kV/33kV Thurkayamjal substation and 33kV/11kV
Hayathnagar substation, APTRANSCO, Andhra Pradesh.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Enhancement of upfc performance with matrix converter using advanced direct p...eSAT Journals
Abstract In this paper presents a direct power control (DPC) for three-phase matrix converters operating as unified power flow controllers (UPFCs). Matrix converters (MCs) allow the direct ac/ac power conversion without dc energy storage links; therefore, the MC-based UPFC (MC-UPFC) has reduced size and cost, reduced capacitor power losses, together with higher reliability. Theoretical principles of direct power control (DPC) based on sliding mode control methods are established for an MC-UPFC dynamic model including the input filter. As a result, line active and reactive power, together with ac supply reactive power, can be directly controlled by selecting an appropriate matrix converter switching state assuring good steady-state and dynamic responses. Experimental results of DPC controllers for MC-UPFC show decoupled active and reactive power control, zero steady-state tracking error, and fast response times. Compared to an MC-UPFC using active and reactive power linear controllers based on a modified Venturini high-frequency PWM modulator, the experimental results of the advanced DPC-MC guarantee faster responses without overshoot and no steady-state error, presenting no cross-coupling in dynamic and steady-state responses. Keywords: Ac/ac conversion advanced direct power controller, matrix converter, unified power flow controller.
A Novel Approach for Allocation of Optimal Capacitor and Distributed Generati...paperpublications3
Abstract: Distributed generation (DG) units, based on their interfacing technology are divided into synchronous generator interfaced DGs, asynchronous generator interfaced DGs and inverter interfaced DGs. This paper presents two algorithms for allocation of optimal capacitor and distributed generation on radial distribution system. These algorithms predict requirement of reactive vars and real power and supplied via capacitor banks and distributed generation. This arrangement reduces transmission losses and voltage stability problem. Developed algorithm has been implemented on two IEEE 69 nodes and 52 nodes systems.
The paper describes the single stage AC-AC converter. This converter is a good alternative to quasi direct back to back converter. This single stage converter is called Matrix Converter. Matrix converter is an array of controlled semiconductor switches that connects three phase source to the three phase load. This converter provides bidirectional power flow, sinusoidal input and output waveforms and they have no dc link storage elements. Simulation model and results presented showing Venturini control method of matrix converter.
Development of a Novel Three Phase Grid-Tied Multilevel Inverter TopologyIAES-IJPEDS
The conventional line-commutated ac-to-dc converters/ inverters have square-shaped line current. It contains higher-order harmonics which generates EMI and it causes more heating of the core of distribution or power transformers. PWM based inverters using MOSFET/IGBT have higher switching losses, and the power handling capability and reliability are quite low in comparison to thyristors/ SCR. A thyristor based forced commutated inverters are not suitable for PWM applications due to the problems of commutation circuits. A pure sinusoidal voltage output or waveform with low harmonic contents is most desirable for ac load using dc to ac conversion. This paper presents a new multilevel inverter topology in which three phase ac- to-dc converter circuits are used in inversion mode by controlling the switching angle. Due to natural commutation, no separate circuit is required for synchronization. In this paper simulation and analysis are done for grid-tied three-phase 6-pulse, Two three-phase, 3-pulse and 12-pulse converter. These converters are analysed for different battery voltage and different switching angle combinations in order to reduce the total harmonic distortion (THD). Three-phase harmonic filters are further added to the grid side to reduce the harmonic content in the line current. A comparative study of these converters is also presented in this paper.
This paper presents the control for Shunt Active Power (SAPF) filter in photovoltaic (PV) systems connected to the grid. The proposed configuration of the system consists of a photovoltaic array that connected to the grid through the three-phase inverter topology that also serves as an active filter. Photovoltaic is coupled in parallel with the direct curret (DC) side of the active filter. With this configuration, can be obtained three advantages, namely the elimination of harmonic currents caused by nonlinear load, reactive power injection, and injection of active power generated photovoltaic. The p-q Theory is used to calculate the harmonic reference current to be used to control the active filter coupled fotovoltaic in generating anti-harmonic currents. The results show that system can reduce harmonic distortion from THD 27.22% to be THD 1.05%, whereas when the active power from photovoltaic injected, the THD become 2.01%. Power sharing can also be seen from this study.
Algorithm for Fault Location and Classification on Parallel Transmission Line...IJECEIAES
This paper proposed a new algorithm for fault location and classification using wavelet based on Clarke’s transformation to obtain the fault current. This novel method of fault current approach is studied by comparing the use of the glide path of the fault voltage. The current alpha and beta (Current Mode) were used to transform the signal using discrete wavelet transform (DWT). The fault location was determined by using the Clarke’s transformation, and then turned into a wavelet, which was very precise and thorough. The most accurate was the mother wavelet Db4 which had the fastest time and smallest error detection when compared with the other wavelet mothers. In this study, the Clarke’s transformation is also compared with the Karenbauer’s, which has produced results with similar error percentage. The simulation results using PSCAD / EMTDC software showed that the proposed algorithm could distinguish internal and external faults to get the current signal in the transformation of a signal fault.
Neural Network based p-q-r Theory for Harmonic Reduction and Neutral Current ...IJECEIAES
The power quality compensator chosen in this paper is a DSTATCOM which integrates a three phase four leg Voltage Source Converter (VSC) with a DC capacitor. The major role of the DSTATCOM is to mitigate the components of harmonic/reactive current present in the line current thereby shapes the grid current to be sinusoidal and improves the power factor nearly unity under varying conditions. In addition DSATATCOM mitigates neutral current (I ) and balances the load currents under unbalanced conditions in three phase four wire (3P4W) distribution system. The control strategy proposed for the DSTATCOM is a Neural Network (NN) based p-q-r theory with two Artificial Neural Network (ANN) controllers for a 3P4W distribution system. The reference signal for 3P3W Shunt Active Power Filter (SAPF) is calculated by implementing an ANN controller. The alleviation of I sn under unbalanced condition is achieved by another ANN controller which produces reference signal for the 1Φ APF. The performance of the proposed DSTATCOM is analysed for various conditions through simulations in MATLAB SIMULINK and the simulation results justify the effectiveness of the propounded NN based control algorithm for DSTATCOM. sn
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
In this paper, a Wavelet modulated isolated two-stage three-phase bidirectional AC-DC converter is proposed for electric vehicle (EV) charging systems. Half-bridge resonant CLLC converter is proposed due to its high efficiency, wide gain range, galvanic isolation and bidirectional power flow. Wavelet modulation technique is used for three-phase six leg AC-DC converter due to its benefits of high DC component and lower harmonic contents. The proposed two-stage converter is developed and simulated in MATLAB Simulink environment. The contribution of this paper is on the implementation and performance analysis of Wavelet modulation in bidirectional AC-DC converters. The results show that Wavelet modulation is suitable to be implemented for the proposed bidirectional converter. The performance of the proposed converter delivers very low output voltage ripple and total harmonic distortion output current of less than 10% which is within the expected results.
State-space averaged modeling and transfer function derivation of DC-DC boost...TELKOMNIKA JOURNAL
This paper presents dynamic analysis of a boost type DC-DC converter for high-brightness LED (HBLED) driving applications. The steady state operation in presence of all system parasitics has been discussed for continuous conduction mode (CCM). The state-space averaging, energy conservation principle and standard linearization are used to derive ac small signal control to inductor current open-loop transfer function of the converter. The derived transfer function can be further used in designing a robust feed-back control network for the system. In the end frequency and transient responses of the derived transfer function are obtained for a given set of component values, hence to provide a useful guide for control design engineers.
DESIGN, SIMULATION, IMPLEMENTATION AND CONTROL OF PLC BASED INTEGRAL CYCLE CO...IAEME Publication
The Class of ac power controllers consists of Solid State Power Controller (SSPC) which connects and disconnects the load to the supply according to the required power. Two important voltage control techniques are commonly used for heating power control in ac power controller are Phase Control Switching and Integral Cycle Control. In case that a PCS is used for the resistive load, it can produce higher order harmonics and heavy inrush current while switching on in a cold start. In the proposed method, a disadvantage of phase controlled is removed. In this paper authors have reported simulated results, design methodology, implementation and Control of PLC Based Integral Cycle Control (ICC) method for Resistance Spot Welding (RSW).
A Novel Optimal PI Parameter Tuning Strategy to Improve Constant Switching Pe...IJPEDS-IAES
This paper presents a novel method of optimal Propotional-Intergral (PI)
controller’s parameter tuning strategy in-order to improve the constant
switching performance of 3-phase direct torque control (DTC) shceme. The
DTC sheme is acknowledged to provide fast decoupled control over the
torque output and stator flux via a simple control structure. However, DTC
sheme has two major downsides, which are the inconsistent inverter
switching frequency and high torque output ripple. The main reason that
contributes to these tribulations is the usage of hysteresis comparators in
order to control the output torque. The realization of PI based controller
method as replacement of hyterisis controller in DTC system able to provide
significant solutions to over come the fall back while retaining the simple
control structure of conventional DTC. The combination usage of higher
sampling controller DS1004 and also 3-level cascaded H-bridge multilevel
inverters (CHMI) in this system can further minimize the output torque ripple
by providing higher resolution with lower digital error and greater number of
vectors. This paper presents detail explanation and calculation of optimal PI
parameter tuning strategy consecutively to enhance the performance of 3-
level DTC system. In order to verify the feasibility of the proposed method
experimentation, the proposed method is compared with convention DTC
system via simulation and experiment results.
A Review to AC Modeling and Transfer Function of DCDC ConvertersRadita Apriana
In this paper, AC modeling and small signal transfer function for DC-DC converters are
represented. The fundamentals governing the formulas are also reviewed. In DC-DC converters, the
output voltage must be kept constant, regardless of changes in the input voltage or in the effective load
resistance. Transfer function is the necessary knowledge to design a proper feedback control such as PID
control to regulate the output voltage as linear PID and PI controllers are usually designed for DC-DC
converters using standard frequency response techniques based on the small signal model of the
converter.
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.
This paper analyses a 3-phase interleaved DC-DC boost converter for the conversion of low input voltage with high input current to higher DC output voltage. The operation of the 3-phase interleaved DC-DC boost converter with multi-parallel of boost converters is controlled by interleaved of switching signals with 120 degrees phase-shifted. Therefore, with this circuit configuraion, high input current is evenly shared among the parallel units and consequently the current stress is reduced on the circuit and semiconductor devices and contributes reduction of overall losses. The simulation and hardware results show that the current stress and the semiconductor conduction losses were reduced approximately 33% and 32%, respectively in the 3-phase interleaved DC-DC boost converter compared to the conventional DC-DC boost converters. Furthermore, the use of interleaving technique with continuous conduction mode on DC-DC boost converters is reducing input current and output voltage ripples to increase reliability and efficiency of boost converters.
This paper presents parameters analysis of 4-level capacitor-clamped boost converter with hard-switching and soft-switching implementation. Principally, by considering the selected circuit structure of the 4-level capacitor-clamped boost converter and appropriate pulse width modulation (PWM) switching strategy, the overall converter volume able to be reduced. Specifically, phase-shifted of 120° of each switching signal is applied in the 4-level capacitor-clamped boost converter in order to increase the inductor current ripple frequency, thus the charging and discharging times of the inductor is reduced. Besides, volume of converters is greatly reduced if very high switching frequency is considered. However, it causes increasing of semiconductor losses and consequently the converter efficiency is affected. The results show that the efficiency of 2-level conventional boost converter and 4-level capacitor-clamped boost converter are 98.59% and 97.67%, respectively in hard-switching technique, and 99.31% and 98.15%, respectively in soft-switching technique. Therefore, by applying soft-switching technique, switching loss of the semiconductor devices is greatly minimized although high switching frequency is applied. In this study, passive lossless snubber circuit is selected for the soft-switching implementation in the 4-level capacitor-clamped boost converter. Based on the simulation results, the switching loss is approximately eliminated by applying soft-switching technique compared to the hard-switching technique implementation.
Small Signal Modelling of a Buck Converter using State Space Averaging for Ma...paperpublications3
Abstract: Nowadays, step-down power converters such as buck scheme are widely employed in a variety of applications such as power supplies, spacecraft power systems, hybrid vehicles and power supplies in particle accelerators. This paper presents a comprehensive small-signal model for the DC-DC buck converter operated under Continuous Conduction Mode (CCM) for a magnetic load. Initially, the buck converter is modeled using state-space average model and dynamic equations, depicting the converter, are derived. The proposed model can be used to design powerful, precise and robust closed loop controller that can satisfy stability and performance conditions of the DC-DC buck regulator. This model can be used in any DC-DC converter (Buck, Boost, and Buck-Boost) by modifying the converter mathematical equations.
Wind Energy Conversion Based On Matrix ConverterIAES-IJPEDS
In recent years renewable sources such as solar, wave and wind are used for the generation of electricity. Wind is one of the major renewable sources. The amount of energy from a Wind Energy Conversion System (WECS) depends not only on the wind at the site, but also on the control strategy used for the WECS. In assistance to get the appropriate wind energy from the conversion system, wind turbine generator will be run in variable speed mode. The variable speed capability is achieved through the use of an advanced power electronic converter. Fixed speed wind turbines and induction generators are often used in wind farms. But the limitations of such generators are low efficiency and poor power quality which necessitates the variable speed wind turbine generators such as Doubly Fed Induction Generator (DFIG) and Permanent Magnet Synchronous Generator (PMSG). A high-performance configuration can be obtained by using a PMSG and a converter in combination AC-DC-AC connect between stator & rotor points for providing the required variable speed operation.
Accurate Symbolic Steady State Modeling of Buck ConverterIJECEIAES
Steady state analysis is fundamental to any electric and electronic circuit design. Buck converter is one of most popular power electronics circuit and has been analyzed in various situations. Although the behavior of buck converters can be understood approximately by the well-known state space averaging method, little is known in the sense of detailed behavior or exact solution to equations. In this paper a steady state analysis of buck converter is proposed which allows the exact calculation of steady state response. Our exact solution is expressed as a Fourier series. Our result is compared with numerical calculation to be verified. Our method copes with more complicated problems such as describing average power and root-mean-square power that are most critical issues in power electronics circuit.
Comparison of symmetrical and asymmetrical cascaded current source multilevel...eSAT Journals
Abstract This paper presents symmetrical and asymmetrical cascaded multilevel inverter approach for high power output applications. It is based on the cascade connection of the H-bridge inverter cells. Comparison of symmetrical and asymmetrical current source multi level inverter is shown using 2 H-bridge inverter cells with cascade connection. Now ever by the supplies which are in GP with different ratios like 2,3,etc. Structural and operational characteristics are discussed and their inherent advantages are shown. Simulation using Matlab Simulink is done to verify the performance. Simulation and results for this proposed scheme are presented in this paper. Index Terms: Asymmetrical cascaded multilevel inverter, Current source multi level inverter, MATLAB Simulink, Optimization angle control, Symmetrical multi level inverter, Total harmonic distortion (THD).
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Similar to Small-Signal AC Model and Closed Loop Control of Interleaved Three-Phase Boost Converter (20)
The aim of this research is the speed tracking of the permanent magnet synchronous motor (PMSM) using an intelligent Neural-Network based adapative backstepping control. First, the model of PMSM in the Park synchronous frame is derived. Then, the PMSM speed regulation is investigated using the classical method utilizing the field oriented control theory. Thereafter, a robust nonlinear controller employing an adaptive backstepping strategy is investigated in order to achieve a good performance tracking objective under motor parameters changing and external load torque application. In the final step, a neural network estimator is integrated with the adaptive controller to estimate the motor parameters values and the load disturbance value for enhancing the effectiveness of the adaptive backstepping controller. The robsutness of the presented control algorithm is demonstrated using simulation tests. The obtained results clearly demonstrate that the presented NN-adaptive control algorithm can provide good trackingperformances for the speed trackingin the presence of motor parameter variation and load application.
This paper presents a fast and accurate fault detection, classification and direction discrimination algorithm of transmission lines using one-dimensional convolutional neural networks (1D-CNNs) that have ingrained adaptive model to avoid the feature extraction difficulties and fault classification into one learning algorithm. A proposed algorithm is directly usable with raw data and this deletes the need of a discrete feature extraction method resulting in more effective protective system. The proposed approach based on the three-phase voltages and currents signals of one end at the relay location in the transmission line system are taken as input to the proposed 1D-CNN algorithm. A 132kV power transmission line is simulated by Matlab simulink to prepare the training and testing data for the proposed 1D- CNN algorithm. The testing accuracy of the proposed algorithm is compared with other two conventional methods which are neural network and fuzzy neural network. The results of test explain that the new proposed detection system is efficient and fast for classifying and direction discrimination of fault in transmission line with high accuracy as compared with other conventional methods under various conditions of faults.
Among the most widespread renewable energy sources is solar energy; Solar panels offer a green, clean, and environmentally friendly source of energy. In the presence of several advantages of the use of photovoltaic systems, the random operation of the photovoltaic generator presents a great challenge, in the presence of a critical load. Among the most used solutions to overcome this problem is the combination of solar panels with generators or with the public grid or both. In this paper, an energy management strategy is proposed with a safety aspect by using artificial neural networks (ANNs), in order to ensure a continuous supply of electricity to consumers with a maximum solicitation of renewable energy.
In this paper, the artificial neural network (ANN) has been utilized for rotating machinery faults detection and classification. First, experiments were performed to measure the lateral vibration signals of laboratory test rigs for rotor-disk-blade when the blades are defective. A rotor-disk-blade system with 6 regular blades and 5 blades with various defects was constructed. Second, the ANN was applied to classify the different x- and y-axis lateral vibrations due to different blade faults. The results based on training and testing with different data samples of the fault types indicate that the ANN is robust and can effectively identify and distinguish different blade faults caused by lateral vibrations in a rotor. As compared to the literature, the present paper presents a novel work of identifying and classifying various rotating blade faults commonly encountered in rotating machines using ANN. Experimental data of lateral vibrations of the rotor-disk-blade system in both x- and y-directions are used for the training and testing of the network.
This paper focuses on the artificial bee colony (ABC) algorithm, which is a nonlinear optimization problem. is proposed to find the optimal power flow (OPF). To solve this problem, we will apply the ABC algorithm to a power system incorporating wind power. The proposed approach is applied on a standard IEEE-30 system with wind farms located on different buses and with different penetration levels to show the impact of wind farms on the system in order to obtain the optimal settings of control variables of the OPF problem. Based on technical results obtained, the ABC algorithm is shown to achieve a lower cost and losses than the other methods applied, while incorporating wind power into the system, high performance would be gained.
The significance of the solar energy is to intensify the effectiveness of the Solar Panel with the use of a primordial solar tracking system. Here we propounded a solar positioning system with the use of the global positioning system (GPS) , artificial neural network (ANN) and image processing (IP) . The azimuth angle of the sun is evaluated using GPS which provide latitude, date, longitude and time. The image processing used to find sun image through which centroid of sun is calculated and finally by comparing the centroid of sun with GPS quadrate to achieve optimum tracking point. Weather conditions and situation observed through AI decision making with the help of IP algorithms. The presented advance adaptation is analyzed and established via experimental effects which might be made available on the memory of the cloud carrier for systematization. The proposed system improve power gain by 59.21% and 10.32% compare to stable system (SS) and two-axis solar following system (TASF) respectively. The reduced tracking error of IoT based Two-axis solar following system (IoT-TASF) reduces their azimuth angle error by 0.20 degree.
Kosovo has limited renewable energy resources and its power generation sector is based on fossil fuels. Such a situation emphasizes the importance of active research and efficient use of renewable energy potential. According to the analysis of meteorological data for Kosovo, it can be concluded that among the most attractive potential wind power sites are the locations known as Kitka (42° 29' 41" N and 21° 36' 45" E) and Koznica (42° 39′ 32″ N, 21° 22′30″E). The two terrains in which the analysis was carried out are mountain areas, with altitudes of 1142 m (Kitka) and 1230 m (Koznica). the same measuring height, about 84 m above the ground, is obtained for these average wind speeds: Kitka 6,667 m/s and Koznica 6,16 m/s. Since the difference in wind speed is quite large versus a difference in altitude that is not being very large, analyses are made regarding the terrain characteristics including the terrain relief features. In this paper it will be studied how much the roughness of the terrain influences the output energy. Also, that the assumption to be taken the same as to how much they will affect the annual energy produced.
Large-scale grid-tied photovoltaic (PV) station are increasing rapidly. However, this large penetration of PV system creates frequency fluctuation in the grid due to the intermittency of solar irradiance. Therefore, in this paper, a robust droop control mechanism of the battery energy storage system (BESS) is developed in order to damp the frequency fluctuation of the multi-machine grid system due to variable active power injected from the PV panel. The proposed droop control strategy incorporates frequency error signal and dead-band for effective minimization of frequency fluctuation. The BESS system is used to consume/inject an effective amount of active power based upon the frequency oscillation of the grid system. The simulation analysis is carried out using PSCAD/EMTDC software to prove the effectiveness of the proposed droop control-based BESS system. The simulation result implies that the proposed scheme can efficiently curtail the frequency oscillation.
This study investigates experimentally the performance of two-dimensional solar tracking systems with reflector using commercial silicon based photovoltaic module, with open and closed loop control systems. Different reflector materials were also investigated. The experiments were performed at the Hashemite University campus in Zarqa at a latitude of 32⁰, in February and March. Photovoltaic output power and performance were analyzed. It was found that the modified photovoltaic module with mirror reflector generated the highest value of power, while the temperature reached a maximum value of 53 ̊ C. The modified module suggested in this study produced 5% more PV power than the two-dimensional solar tracking systems without reflector and produced 12.5% more PV power than the fixed PV module with 26⁰ tilt angle.
This paper focuses on the modeling and control of a wind energy conversion chain using a permanent magnet synchronous machine. This system behaves a turbine, a generator, DC/DC and DC/AC power converters. These are connected on both sides to the DC bus, where the inverter is followed by a filter which is connected to the grid. In this paper, we have been used two types of controllers. For the stator side converter, we consider the Takagi-Sugeno approach where the parameters of controller have been computed by the theory of linear matrix inequalities. The stability synthesis has been checked using the Lyapunov theory. According to the grid side converter, the proportional integral controller is exploited to keep a constant voltage on the DC bus and control both types of powers. The simulation results demonstrate the robustness of the approach used.
The development of modeling wind speed plays a very important in helping to obtain the actual wind speed data for the benefit of the power plant planning in the future. The wind speed in this paper is obtained from a PCE-FWS 20 type measuring instrument with a duration of 30 minutes which is accumulated into monthly data for one year (2019). Despite the many wind speed modeling that has been done by researchers. Modeling wind speeds proposed in this study were obtained from the modified Rayleigh distribution. In this study, the Rayleigh scale factor (Cr) and modified Rayleigh scale factor (Cm) were calculated. The observed wind speed is compared with the predicted wind characteristics. The data fit test used correlation coefficient (R2), root means square error (RMSE), and mean absolute percentage error (MAPE). The results of the proposed modified Rayleigh model provide very good results for users.
This paper deals with an advanced design for a pump powered by solar energyto supply agricultural lands with water and also the maximum power point is used to extract the maximum value of the energy available inside the solar panels and comparing between techniques MPPT such as Incremental conductance, perturb & observe, fractional short current circuit, and fractional open voltage circuit to find the best technique among these. The solar system is designed with main parts: photovoltaic (PV) panel, direct current/direct current (DC/DC) converter, inverter, filter, and in addition, the battery is used to save energy in the event that there is an increased demand for energy and not to provide solar radiation, as well as saving energy in the case of generation more than demand. This work was done using the matrix laboratory (MATLAB) simulink program.
The objective of this paper is to provide an overview of the current state of renewable energy resources in Bangladesh, as well as to examine various forms of renewable energies in order to gain a comprehensive understanding of how to address Bangladesh's power crisis issues in a sustainable manner. Electricity is currently the most useful kind of energy in Bangladesh. It has a substantial influence on a country's socioeconomic standing and living standards. Maintaining a stable source of energy at a cost that is affordable to everyone has been a constant battle for decades. Bangladesh is blessed with a wealth of natural resources. Bangladesh has a huge opportunity to accelerate its economic development while increasing energy access, livelihoods, and health for millions of people in a sustainable way due to the renewable energy system.
When the irradiance distribution over the photovoltaic panels is uniform, the pursuit of the maximum power point is not reached, which has allowed several researchers to use traditional MPPT techniques to solve this problem Among these techniques a PSO algorithm is used to have the maximum global power point (GMPPT) under partial shading. On the other hand, this one is not reliable vis-à-vis the pursuit of the MPPT. Therefore, in this paper we have treated another technique based on a new modified PSO algorithm so that the power can reach its maximum point. The PSO algorithm is based on the heuristic method which guarantees not only the obtaining of MPPT but also the simplicity of control and less expensive of the system. The results are obtained using MATLAB show that the proposed modified PSO algorithm performs better than conventional PSO and is robust to different partial shading models.
A stable operation of wind turbines connected to the grid is an essential requirement to ensure the reliability and stability of the power system. To achieve such operational objective, installing static synchronous compensator static synchronous compensator (STATCOM) as a main compensation device guarantees the voltage stability enhancement of the wind farm connected to distribution network at different operating scenarios. STATCOM either supplies or absorbs reactive power in order to ensure the voltage profile within the standard-margins and to avoid turbine tripping, accordingly. This paper present new study that investigates the most suitable-location to install STATCOM in a distribution system connected wind farm to maintain the voltage-levels within the stability margins. For a large-scale squirrel cage induction generator squirrel-cage induction generator (SCIG-based) wind turbine system, the impact of STATCOM installation was tested in different places and voltage-levels in the distribution system. The proposed method effectiveness in enhancing the voltage profile and balancing the reactive power is validated, the results were repeated for different scenarios of expected contingencies. The voltage profile, power flow, and reactive power balance of the distribution system are observed using MATLAB/Simulink software.
The electrical and environmental parameters of polymer solar cells (PSC) provide important information on their performance. In the present article we study the influence of temperature on the voltage-current (I-V) characteristic at different temperatures from 10 °C to 90 °C, and important parameters like bandgap energy Eg, and the energy conversion efficiency η. The one-diode electrical model, normally used for semiconductor cells, has been tested and validated for the polemeral junction. The PSC used in our study are formed by the poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM). Our technique is based on the combination of two steps; the first use the Least Mean Squares (LMS) method while the second use the Newton-Raphson algorithm. The found results are compared to other recently published works, they show that the developed approach is very accurate. This precision is proved by the minimal values of statistical errors (RMSE) and the good agreement between both the experimental data and the I-V simulated curves. The obtained results show a clear and a monotonic dependence of the cell efficiency on the studied parameters.
The inverter is the principal part of the photovoltaic (PV) systems that assures the direct current/alternating current (DC/AC) conversion (PV array is connected directly to an inverter that converts the DC energy produced by the PV array into AC energy that is directly connected to the electric utility). In this paper, we present a simple method for detecting faults that occurred during the operation of the inverter. These types of faults or faults affect the efficiency and cost-effectiveness of the photovoltaic system, especially the inverter, which is the main component responsible for the conversion. Hence, we have shown first the faults obtained in the case of the short circuit. Second, the open circuit failure is studied. The results demonstrate the efficacy of the proposed method. Good monitoring and detection of faults in the inverter can increase the system's reliability and decrease the undesirable faults that appeared in the PV system. The system behavior is tested under variable parameters and conditions using MATLAB/Simulink.
The electrical distribution network is undergoing tremendous modifications with the introduction of distributed generation technologies which have led to an increase in fault current levels in the distribution network. Fault current limiters have been developed as a promising technology to limit fault current levels in power systems. Though, quite a number of fault current limiters have been developed; the most common are the superconducting fault current limiters, solid-state fault current limiters, and saturated core fault current limiters. These fault current limiters present potential fault current limiting solutions in power systems. Nevertheless, they encounter various challenges hindering their deployment and commercialization. This research aimed at designing a bridge-type nonsuperconducting fault current limiter with a novel topology for distribution network applications. The proposed bridge-type nonsuperconducting fault current limiter was designed and simulated using PSCAD/EMTDC. Simulation results showed the effectiveness of the proposed design in fault current limiting, voltage sag compensation during fault conditions, and its ability not to affect the load voltage and current during normal conditions as well as in suppressing the source powers during fault conditions. Simulation results also showed very minimal power loss by the fault current limiter during normal conditions.
This paper provides a new approach to reducing high-order harmonics in 400 Hz inverter using a three-level neutral-point clamped (NPC) converter. A voltage control loop using the harmonic compensation combined with NPC clamping diode control technology. The capacitor voltage imbalance also causes harmonics in the output voltage. For 400 Hz inverter, maintain a balanced voltage between the two input (direct current) (DC) capacitors is difficult because the pulse width modulation (PWM) modulation frequency ratio is low compared to the frequency of the output voltage. A method of determining the current flowing into the capacitor to control the voltage on the two balanced capacitors to ensure fast response reversal is also given in this paper. The combination of a high-harmonic resonator controller and a neutral-point voltage controller working together on the 400 Hz NPC inverter structure is given in this paper.
Direct current (DC) electronic load is a useful equipment for testing the electrical system. It can emulate various load at a high rating. The electronic load requires a power converter to operate and a linear regulator is a common option. Nonetheless, it is hard to control due to the temperature variation. This paper proposed a DC electronic load using the boost converter. The proposed electronic load operates in the continuous current mode and control using the integral controller. The electronic load using the boost converter is compared with the electronic load using the linear regulator. The results show that the boost converter able to operate as an electronic load with an error lower than 0.5% and response time lower than 13 ms.
More from International Journal of Power Electronics and Drive Systems (20)
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
2. Int J Power Electron & Dri Syst ISSN: 2088-8694
Small Signal AC Model and Closed Loop Control of Interleaved 3 Phase Boost …(H.V.Gururaja Rao)
241
Many design procedures in the literature are empirically derived, its derivation process and
descriptions are not provided. Thus, for a given system it is difficult to follow and evaluate these procedures
[4], [7]. In this paper type III compensator is mathematically analyzed and employed. A linear control
technique can be applied to a linear system, but all the switch mode power supply systems are non-linear as
the system during one switching sub-interval is not the same as in other sub-interval. So, the power converter
system needs to be modeled to a linear system in order to apply a linear control technique. The objective of
the small signal ac modeling is to predict how small signal low-frequency ac variations in duty cycle results
in small signal low frequency ac variations in the converter voltage and current waveforms.
Interleaved boost converters are now extensively used for wide range of applications. Benefits of
multidevice interleaved converters over conventional converters for fuel cell applications is discussed in [10].
A PV fed interleaved boost converter is proposed for agricultural applications in [11]. Small signal model for
n phase interleaved boost converter is presented in [12]. Only open loop control studies are performed. The
small signal ac converter model is obtained by removing switching harmonics and averaging all sub-interval
waveforms over one switching period .An averaged model implies the disappearance of any switching event
to the benefit of a smoothly varying continuous signal. The averaged voltages and currents, in general
comprises nonlinear functions of the converter duty cycle, voltages, and currents and results in a system of
nonlinear differential equations [4]. Hence, it must be linearized to construct a small-signal linear converter
model and is discussed in general in section 2.
2. STATE SPACE AVERAGE MODEL
It is a common practice to select state variables based on energy storage elements [6]. Unlike
conventional dc-dc converter which has two states during each switching period, due to interleaved switching
sequence of multi-Phased converter, it undergoes various different states, depending on the number of phase.
The duration of each state is derived with relative to its duty ratio and the switching period. In three-phase
dc-dc converter, the different phase switches are operated with relative phase shifts of 120 degree [13].
Phase I
Phase II
Phase III
Ts
(D-2/3)Ts
(1-D)Ts
I II III IV V VI
rl1
L1
S11
ron11
C
rl2
L2
rl3
L3
ron12 ron13
S12 S13
S21
S22
S23
rc
Vin
ron21
ron22
ron23
R
Figure 1. Three-Phase Interleaved switching pulse Figure 2. Three-Phase boost converter
The gate pulse for interleaved three-phase dc-dc converter is shown Figure.1. Due to interleaved
switching, the three-phase system exhibits six states in each switching cycle. The states I, III and V lasts for
(D – 2/3), while states II, IV, and VI lasts for (1-D) times the switching period Ts [13].
For a three-phase dc-dc converter shown in Figure 2, operating in continuous conduction mode,
operating states form the state vector x(t), and the independent sources that drive the converter form the
input vector u(t). During each subinterval of a switching period, the converter reduces to the linear circuit
that can be represented by the following state equations as,
dx(t)
d(t)
= Anx(t) + Bnu(t)
(1)
y(t) = Cnx(t) + Enu(t) (2)
3. ISSN: 2088-8694
Int J Power Electron & Dri Syst, Vol. 9, No. 1, March 2018 : 240 – 251
242
During each of the subintervals, the circuit configuration is different and represent different linear
circuits; hence, the corresponding state equation matrices may also differ. These state equations are used to
obtain small-signal ac model [2], [6].
Since the switching frequency of the converter is generally very much greater than the converter input
frequency variations , the equilibrium state equations of the converter is given as,
0 = AX + BU (3)
Y = CX + DU (4)
Where, A = (A1 + A3 + A5) (D −
2
3
) … + (A2 + A4 + A6)(1 − D)
(5)
B = (B1 + B3 + B5) (D −
2
3
) … + (B2 + B4 + B6)(1 − D)
(6)
C = (C1 + C3 + C5) (D −
2
3
) … + (C2 + C4 + C6)(1 − D)
(7)
E = (E1 + E3 + E5) (D −
2
3
) … + (E2 + E4 + E6)(1 − D)
(8)
Here X, U and Y represent the state, input and output vectors respectively and D is the duty cycle.
By perturbation and linearization of the converter waveforms around its quiescent operating point [2], [14],
the state equation of the small signal ac model is given as,
dx(t)
dt
= Ax
̂(t) + Bu
̂(t) + Md
̂(t)
(9)
y
̂(t) = Cx
̂(t) + Nd
̂(t)
(10)
where û (t) and d
̂(t) represent small changes in the input vector and duty ratio. The vector x
̂(t) and
ŷ(t) are the resulting small deviations in the state and output vector. Here it is assumed that, in comparision
with the quiescent values, these deviations are much less [2].The matrices M and N are given as
M = ((A1 + A3 + A5) − (A2 + A4 + A6))X … + ((B1 + B3 + B5) − (B2 + B4 + B6))U
(11)
= ((C1 + C3 + C5) − (C2 + C4 + C6))X … + ((E1 + E3 + E5) − (E2 + E4 + E6))U (12)
rl1
L1
ron11
C
rl2
L2
rl3
L3
ron12 ron13
R
rc
Vin
rl1
L1
ron11
C
rl2
L2
rl3
L3
ron13
R
ron22
rc
Vin
Figure 3 (a) State I, III and V Figure 3 (b) State II
4. Int J Power Electron & Dri Syst ISSN: 2088-8694
Small Signal AC Model and Closed Loop Control of Interleaved 3 Phase Boost …(H.V.Gururaja Rao)
243
rl1
L1
ron11
C
rl2
L2
rl3
L3
ron12
R
ron23
rc
Vin
rl1
L1
C
rl2
L2
rl3
L3
ron11
R
ron21
rc
ron12
Vin
Figure 3 (c) State IV Figure 3 (d) State VI
2.1 Small Signal ac modelling of Three-Phase Boost Converter
Figure.2 shows a Three-Phase boost converter with synchronous switching. Very low voltage drop
across the MOSFETs compared to diodes, resulting in higher efficiency is the prime advantage of
synchronous switching dc-dc converter [14]. The conduction losses of the MOSFETs are modeled by on-
resistance ron, the dc resistance of the inductor as rl and equivalent series resistance of the capacitor as rc. The
inductor current and capacitor voltage being independent states of the converter comprise the state vector.
The input voltage Vin(t) being independent source comprise the input vector as,
𝑥(𝑡) = [𝑖𝐿1 (𝑡) 𝑖𝐿2 (𝑡) 𝑖𝐿3 (𝑡) 𝑉
𝑐 (𝑡)] ′ (13)
u(t) = [Vin(t)] (14)
The output vector is formed by the output port voltage variable Vo(t)
y(t) = [vo(t)] (15)
In order to have state equations for each subinterval, the circuit is analyzed for six different states during its
switching period.
2.1.1 State I:
All the three low side switches S11, S12 and S13 are closed, while its complementary switches S21, S22
and S23 are let open..The reduced linear circuit is shown in Figure 3 (a)
The state equations for inductor voltage,
L1
diL1(t)
dt
= Vin(t) − iL1(t)(rl1 + ron11)
(16)
L2
diL2(t)
dt
= Vin(t) − iL2(t)(rl2 + ron12)
(17)
L3
diL3(t)
dt
= Vin(t) − iL3(t)(rl3 + ron13)
(18)
Capacitor current, C
dvc(t)
dt
= − (
vc(t)
R+rc
)
(19)
and Output voltage,
vo(t) = (
vc(t)R
R + rc
)
(20)
2.1.2 State II:
The low side switch S12 is turned OFF; while it’s complementary S22 is turned ON. Thus the stored energy in
inductor L2 is freewheeled through switch S22 .Thus, the reduced linear circuit is shown in Figure 3 (b) The
phase I and phase III continues to store energy, thus the phase II inductor voltage is given as,
diL2(t)
dt
= Vin(t) − iL2(t) (rl2 + +
Rrc
R + rc
) … −
vc(t)R
R + rc (21)
5. ISSN: 2088-8694
Int J Power Electron & Dri Syst, Vol. 9, No. 1, March 2018 : 240 – 251
244
Capacitor current, C
dvc(t)
dt
=
iL2(t)R
R+rc
−
vc(t)
R+rc
(22)
Output voltage, vo = (
Rrc
R+rc
) iL2(t) + (
R
R+rc
) vc(t) (23)
2.1.3 State III: State III is similar to state I, where all the low side switches are closed and the inductors store
energy.
2.1.4 State IV:
Complementary S23 is turned ON. Thus the stored energy in inductor L3 is freewheeled through
switch S23. The reduced linear circuit is shown in Figure 3 (c). Thus the phase III inductor voltage is given as,
L3
diL3(t)
dt
= Vin(t) − iL3(t) (rl3 + ron23 +
Rrc
R + rc
) … −
vc(t)R
R + rc
(24)
Capacitor current, C
dvc(t)
dt
=
iL3(t)R
R+rc
−
vc(t)
R+rc
(25)
Output voltage, vo = (
Rrc
R+rc
) iL3(t) + (
R
R+rc
) vc(t)
(26)
2.1.5 State V: State V is similar to state I, where all the low side switches are closed and the inductors store
energy.
2.1.6 State VI:
The low side switch S11 is turned OFF; while it’s complementary S21 is turned ON. Thus the stored
energy in inductor L1 is freewheeled through switch S11. The reduced linear circuit is shown Figure 3 (d).
Thus the phase I inductor voltage is given as,
diL1(t)
dt
= Vin(t) − iL1(t) (rl1 + ron21 +
Rrc
R + rc
) … −
vc(t)R
R + rc (27)
Capacitor current,
C
dvc(t)
dt
=
iL1(t)R
R + rc
−
vc(t)
R + rc
(28)
Output voltage, vo = (
Rrc
R+rc
) iL1(t) + (
R
R+rc
) vc(t) (29)
The six state matrices, input vectors and output vectors are identified and evaluated for state-space
averaged equations [2]. The approximations considered here are, all the three phase inductance is same and
its rating too, thus its dc resistance is approximately equal to each other, and can be given as rl. Similarly, all
the same rated MOSFET’s on-resistance is approximated to ron and let rl + ron = rl′.
Also, R + rc = R as R >> rc
Thus, using (5) and (16) to (29) the Averaged matrix A, is given by
[
− (
rl′ + rcD
́
L1
) 0 0 −
D
́
L1
0 − (
rl′ + rcD
́
L2
) 0 −
D
́
L2
0 0 − (
rl′ + rcD
́
L3
) −
D
́
L3
D
́
C
D
́
C
D
́
C
−
1
CR]
(30)
Similarly, using (6), (7) and (16) to (29) the averaged matrix B and C,
6. Int J Power Electron & Dri Syst ISSN: 2088-8694
Small Signal AC Model and Closed Loop Control of Interleaved 3 Phase Boost …(H.V.Gururaja Rao)
245
B =
[
1
L1
⁄
1
L2
⁄
1
L3
⁄
0 ]
(31)
C = [D
́ rc D
́ rc D
́ rc 1] (32)
Using (11) and (12), vector coefficient of d
̂(t) is given as,
𝑀 = [
𝑉𝑖𝑛
𝐿1 𝐷
𝑉𝑖𝑛
𝐿2 𝐷
𝑉𝑖𝑛
𝐿3𝐷
− 𝑉𝑖𝑛
𝐶𝑅𝐷2
]
′
(33)
N = [
−Vinrc
RD
́ 2
]
(34)
Figure 4. Small-signal ac model of Three-Phase boost converter
The small signal ac equations are obtained by perturbation with small ac variation and linearization
with removal of DC terms and higher order terms [2], [14]. Thus, small-signal model is found by evaluation
of (9), (10). When written in scalar form, the three-phase inductor voltages are given as,
L1
dîL1(t)
dt
= v
̂in(t) − îL1(t)(rl′
+ rcD
́ ) − v
̂c(t)D
́ … + (
Vin
D
́
) d
̂(t) (35)
L2
dîL2(t)
dt
= v
̂in(t) − îL2(t)(rl′
+ rcD
́ ) − v
̂c(t)D
́ … + (
Vin
D
́
) d
̂(t)
(36)
L3
dîL3(t)
dt
= v
̂in(t) − îL3(t)(rl′
+ rcD
́ ) − v
̂c(t)D
́ … + (
Vin
D
́
) d
̂(t)
(37)
The capacitor current is given as,
C
dv
̂c(t)
dt
= îL1(t)D
́ + îL2(t)D
́ + îL3(t)D
́ −
v
̂c(t)
R
… − (
v
̂in
RD
́ 2
) d
̂(t)
(38)
The output equation,
v
̂o(t) = (îL1(t) + îL2(t) + îL3(t))D
́ rc − v
̂c(t) … − (
v
̂inrc
RD
́ 2
) d
̂(t)
(39)
Circuits corresponding to equations (35) – ((39) are combined into a complete small-signal ac
equivalent circuit model of non-ideal three-phase boost converter as shown in Figure 4. This will aid in
frequency response based control system design.
7. ISSN: 2088-8694
Int J Power Electron & Dri Syst, Vol. 9, No. 1, March 2018 : 240 – 251
246
2.2 Closed loop control of three phase boost converter
Open loop characteristics is essential to analyse the performance and stability of the control system
that regulates the converter output voltage. The necessary transfer function is obtained by making the line
voltage variation û(s) zero and then solving for the transfer function from d
̂(s) to v
̂o(s) [2], [14]. Thus,
v
̂o(s)
d
̂(s)
= C(SI − A)−1
M + N
(40)
v
̂o
d
̂
= Gdo (
(1 +
s
ωesr
) (1 −
s
ωrhp
)
(1 +
s
Qωo
+
s2
ωo
2)
) (41)
Where,
DC gain is given by, Gdo = Vg (
3R(3RD′2
−rl′)
(3RD′2
+rl′)(3RD′+D′rc+rl′)
)
ωo = √(
3RD′2+D′rc+rl′
CLR
); Q = ωo (
1
1
CR
+
D′rc+rl′
L
);
ωrhp = 1 −
s
(
3D′2R−(rl′)
L
)
; ωesr = 1 + (
s
1
Crc
⁄
)
The three-phase boost converter in its voltage mode control will have four main characteristics, a
double pole due to LC filter which moves with operating conditions, an ESR zero due to equivalent series
resistance of output capacitor, Right half plane zero and finally a variable gain dependent upon the input
voltage of the converter [2].
Closed loop control systems are usually associated with stability and response time issues which
may conditionally affect the output; even though control loop allows the converter to adjust to load variations
or changes in the input voltage [10]. For compensated system, high DC gain ensures that the steady-state
error between the output and the reference signal is small [4], [5]. Enough phase margin and bandwidth
ensures satisfactory stability margin and transient response [4], [14].
2.2.1 Right half plane zero
A three-phase boost converter in voltage mode control will have an additional zero in the right half.
With right half zero, it is a challenging design task to stabilize converter when operating with voltage mode
control [5], [9]. RHP zero is introduced when the duty ratio is increased (low-side switch is of boost
converter is switched on for a longer duration). The output initially reduces, in spite of the control command
trying to increase it. This in fact is the characteristics of a zero in the right half; a rise in the control command
to the system results in an initial reduction in the output response. After about 4 to 5 times the time constant
associated with the right half zero, the output follows the input control command. Hence in a system with a
RHP zero, the control system will take a certain time to respond to any changes in the output; response is not
immediate [5]. In order to overcome this problem and to stabilize the system, the loop bandwidth must be
much less than the frequency of the right half zero [7], [3].
3. RESULTS AND DISCUSSION
3.1 Type III Compensator Design Procedure
Type III compensator has a phase angle 90° at some frequencies. Required phase boost is therefore
available to attain the desired phase margin. Figure 5 shows a closed loop three-phase boost converter with
type III compensator in its feedback path. A type III compensator will have two zeros and three poles, with a
pole at the origin [3]. Here, it is intended to place zeros coincident, one pole at origin and the remaining poles
coincident to each other. Thus equation (42) gives the desired transfer function.
C(s) =
K (1 +
s
ωZ
)
2
s (1 +
s
ωP
)
2
(42)
8. Int J Power Electron & Dri Syst ISSN: 2088-8694
Small Signal AC Model and Closed Loop Control of Interleaved 3 Phase Boost …(H.V.Gururaja Rao)
247
Figure 5. Closed loop voltage mode controlled three-phase boost converter
From (42), at any frequency ω, the amplitude and phase of the transfer function are given by (43) and (44)
respectively and (44) is rewritten as (45).
C(jω) =
K
ω
|(1 + j
ω
ωz
)
2
|
|(1 + j
ω
ωP
)
2
|
=
K
ω
1 + (
ω
ωZ
)
2
1 + (
ω
ωP
)
2
(43)
φ[C(jω)] = φ (
K
jω
) + φ (1 +
jω
ωZ
)
2
− φ (1 +
jω
ωP
)
2
(44)
φ[C(jω)] = −
π
2
+ 2φ (1 + j
ω
ωZ
) − 2φ (1 + j
ω
ωP
)
(45)
From (45), the phase of C (jω) comprise of a constant value of – π /2 due to the pole at the origin, and a
variable portion as a function of frequency ω,
φv(jω) = 2tan−1
ω(ωP − ωZ)
ω2 + ωZωP
(46)
At the geometric mean of the ωz and ωp the maximum variable phase angle occurs and is given as,
ωm = √ωPωZ
(47)
Here, let ωm be the maximum phase frequency of a type III compensator.
Let k =
ωP
ωZ
(48)
Then the maximum phase of φv(ω) can be written as,
φv(ωm) = 2tan−1
(
k − 1
2√k
) (49)
Finally, the maximum phase of the type III compensator is given as,
φ[C(jωm)] = −
π
2
+ 2tan−1
(
k − 1
2√k
) (50)
Vg
rl1 L1
ron11
C
Driver
ron21
rc Load
Vref
+
_
S11
S21
Vc
d
PWM
rl2 L2
ron12
Driver –
120º
ron22
S12
S22
rl3 L3
ron13
Driver –
240º
ron23
S13
S23
Vi
Vo
C2
R2
C1
C3
R3
R1
+
_
9. ISSN: 2088-8694
Int J Power Electron & Dri Syst, Vol. 9, No. 1, March 2018 : 240 – 251
248
Here, ‘k’ is a measure of the separation between the zero and pole frequency. Due to RHP zero in
the boost converter, it is non-minimum phase system, because of which extra phase lag is added to the system
and it makes the system conditionally stable. Due to RHP zero, the system’s phase plot goes below -180º,
(more negative), but comes back again to -180º. Thus, it is required to have a phase boost at maximum phase
lag frequency ωmp [3]. Also, to attain desired phase margin and for loop stability, phase boost is necessary at
the crossover frequency too. Thus the maximum phase boost frequency ωm by type III compensator is
required to be placed somewhere between ωmp and ωc [3]. The ωm is given by,
ωm = α√ωmpωc (51)
In order to attain the desired phase margin and bandwidth, α need to be adjusted. Thus, by adjusting
the ‘α’ on trial and error basis, unconditional stability can be achieved. Once the ωm is selected for the given
system, and provided the ωm, Gp, ωmp and φp are noted. Using (50) and (46), it can be written as,
2tan−1
(
ωc(ωp − ωz)
ωc
2 + ωzωp
) = φm − φp −
π
2
(52)
ωc(ωp − ωz)
ωc
2 + ωpωz
= tan (
φm − φp
2
−
π
4
) (53)
Based on (52) and (53), the following two equations are obtained,
ωpωz = ωm
2
(54)
ωp − ωz = ωd
(55)
Where ωd is defined as, ωd = tan (
φm−φP
2
−
π
4
) (ωd + ωmp) (56)
From (54) and (55), the compensator’s zero and pole frequencies are given as,
ωz = 0.5 (√ωd
2 + ωm
2 − ωd) (60)
ωp = 0.5 (√ωd
2 + ωm
2 + ωd)
(61)
The separation factor is be calculated as, k =
√ωd
2+ωm
2+ ωd
√ωd
2+ωm
2− ωd
(62)
From (50), it is known that, |C(jωc)| =
K
ωc
1+(
ωc
ωZ
)
2
1+(
ωc
ωP
)
2
At the crossover frequency, |C(jωc)|GP = 1
Thus, the gain K is, K =
ωc(1+(
ωc
ωP
)
2
)
GP(1+(
ωc
ωz
)
2
)
(63)
(64)
(65)
10. Int J Power Electron & Dri Syst ISSN: 2088-8694
Small Signal AC Model and Closed Loop Control of Interleaved 3 Phase Boost …(H.V.Gururaja Rao)
249
Figure 6. Frequency response of Three-Phase boost converter
3.2 Control System Design for Three-Phase Boost Converter
Design specifications of three phase boost converter is given Table.1.
Table.1. Three-Phase Boost converter design specifications
Specifications
Vin 12 V
Vout 40 V
Power 700 watts
Switching frequency 100 kHz
Three-Phase Component details
Phase
Inductance,
DCR
Switch ON
Resistance
mΩ
Capacitance,
ESR
I 6.08µH, 5mΩ
S11 20
56µF, 10mΩ
S21 20
II 6.08µH, 5mΩ
S12 20
S22 20
III 6.08µH, 5mΩ
S13 20
S23 20
3.2.1 Compensator Design
Figure 6 shows the open loop, control-to-output, uncompensated, Bode plot for three-phase boost
converter. From Figure 6 the compensator can be designed by following the procedure given from (42) to
(62). The crossover frequency i.e. the bandwidth of the compensated system is generally chosen to be less
than one-fifth of switching frequency [2], [4]. In this case, the chosen crossover frequency is 7 kHz. The gain
and the phase angle at 7 kHz are noted to aid in compensator design. From Figure 6, the gain and the phase
angle at 7 kHz were found to be 36.5dB and -159° respectively and also the maximum phase lag due to RHP
zero dips at 70 kHz. A phase margin of 70° ° is considered to ensure good stability and better transient
response.
-60
-40
-20
0
20
40
60
80
Magnitude
(dB)
10
0
10
1
10
2
10
3
10
4
10
5
10
6
10
7
90
135
180
225
270
315
360
Phase
(deg)
Bode Diagram
Gm = 10.7 dB (at 4.39e+004 Hz) , Pm = 69.3 deg (at 6.99e+003 Hz)
Frequency (Hz)
Uncompensated system
Compensated system
-60
-40
-20
0
20
40
60
80
Magnitude
(dB)
10
0
10
1
10
2
10
3
10
4
10
5
10
6
10
7
90
135
180
225
270
315
360
Phase
(deg)
High DC Gain
11. ISSN: 2088-8694
Int J Power Electron & Dri Syst, Vol. 9, No. 1, March 2018 : 240 – 251
250
Figure 7. Transient response of Three-Phase boost converter
3.3 Discussion
The desired frequency response with high DC gain, enough bandwidth and phase margin is evident
from the Fig.6. The complete closed loop compensated system is tested for instant variable load to observe
the transient response. Fig.7 shows the output voltage waveform for regulated and unregulated three-phase
boost converter. From the Fig.7, when load is varied, the output voltage of unregulated system varies, while
in the regulated system the output voltage settles back to its desired reference voltage. Thus, this type of
closed loop regulated system; find its utmost application in point of load power supplies.
4. CONCLUSION
The foremost feature of the multi-phased boost converter, self-regulation of output, is easily achieved
by designing a closed loop control circuit which in turn is aided by small-signal ac model of the dc-dc
converter. The state-space averaging of several sub-intervals during one switching period results in accurate
small-signal ac model. The designing of compensator circuit for closed loop control is aided by the frequency
response of the small-signal ac model of dc-dc converter. The compensated system met desired frequency
domain responses such as, high DC gain, enough bandwidth and required phase margin for unconditional
stability. The difficulty in the compensation of the non-minimum phase system, due to maximum phase lag is
overcome by appropriate pole-zero placement of type III compensator. The step-by-step design procedure for
type III compensator leads to have an easy methodology for control system design. The closed loop regulated
system is tested for variable load and compared with unregulated system. The small-signal ac modelling and
closed loop control of multi-phase dc-dc converter paves the way to have an advanced design methodology for
high power applications requiring tight voltage regulation.
REFERENCES
[1] H. B. Shin, E. S. Jang, J. G. Park, H. W. Lee, and T. A. Lipo, “Small signal Analysis of Multiphase Interleaved
Boost converter with Coupled Inductors,” IEEE Proc. Electric Power Applications, vol.152 ,no.5, pp. 1161–
1170,Sep. 2005.
[2] J. Perduľak, D. Kováč, “A Novel Multiphase Boost Converter with High Energy Efficiency” Technical University
of Košice.
[3] Erickson, Robert W. “Fundamentals of Power Electronics” Second Edition. Secaucus, NJ, USA: Kluwer Academic
[4] Liyu Cao, “Type III compensator Design for Power Converters”, Design features,Power Electronic
Technology,2011
[5] Karuna Mudliyar, Suryanarayana K, H.V. Gururaja Rao, “Analysis of High-Frequency Multi-Phase Multi-Stage
Boost Converter”, International Journal of Advanced Electrical and Electronics Engineering, (IJAEEE), ISSN
(Print): 2278-8948, Volume-2, Issue-1, 2013.
[6] Dr. Raymond B. Ridley “Power Supply Design – Volume I: Control” First Edition, ISBN 978-0-9833180-0-2.
0 1 2 3 4 5 6 7 8
x 10
-3
10
20
30
40
50
60
Time
Voltage
(V)
Output Voltage under variable load
0 1 2 3 4 5 6 7 8
x 10
-3
0
10
20
30
Time
Current
(A)
Load current under variable load
0 1 2 3 4 5 6 7 8
x 10
-3
0
10
20
30
Time
Current
(A)
Load current under variable load
0 1 2 3 4 5 6 7 8
x 10
-3
10
20
30
40
50
60
Time
Output Voltage under variable load
Regulated Output
Unregulated Output
100% Load
50 % Load
0% Load
125% Load
12. Int J Power Electron & Dri Syst ISSN: 2088-8694
Small Signal AC Model and Closed Loop Control of Interleaved 3 Phase Boost …(H.V.Gururaja Rao)
251
[7] Mohammad Faridun Naim Tajuddin, Nasrudin Abdul Rahim “Small-signal AC modeling Technique of Buck
Converter with DSP Based Proportional-Integral-Derivative (PID) Controller” IEEE Symposium on Industrial
Electronics and Applications (ISIEA 2009), October 4-6, 2009, Kuala Lumpur, Malaysia
[8] Wenkang Huang, “A New Control for Multi-phase Buck Converter with Fast Transient Response” 0-7803-6618-
2/01/ 2001 IEEE.
[9] Chuanyun Wang, “Investigation on Interleaved Boost Converters and Applications” PhD thesis, Virginia
Polytechnic Institute and State University, 2009.
[10] R. Seyezhai, “ Simulation and hardware implementation of a multi device interleaved boost converter for fuel cell
applications”, International journal of Power Electronics and drive systems, Volume 4, Issue 3, September 2014.
[11] Adireddy Ramesh, M.Sivakumar, A. Chandra shekhar, “ Interleaved boost converter fed with PV for Induction
motor / agricultural applications”, International journal of Power Electronics and drive systems, Vol. 7, Issue 3,
Sep. 2016.
[12] Apoorv Yadav, Abhishek Awasthi et.al, “Small signal modelling and stability analysis of N – phase interleaved
boost converter”, IEEE international conference on electrical, computer and electronics engineering, December
2016, Varanasi, India.
[13] Daniel W. Hart “Power Electronics” McGraw-Hill, Third Edition, ISBN 978-0-07 338067-4.
[14] Basso, C. “Switch Mode Power Supplies: SPICE Simulations and Practical Designs”, McGraw-Hill, 2008