This document summarizes research on switchable transformers conducted at the University of South Australia since 2000. It describes the initial development of a 1kVA switchable transformer with series and parallel winding configurations to improve efficiency compared to a conventional transformer. Testing showed efficiency gains. Later studies expanded this to 3kVA and 10kVA three-phase switchable transformers. Finite element analysis was used to optimize core design. Recent work investigated using a microcontroller and CAN bus for control and monitoring, and adaptive fuzzy logic control. The research aims to further improve efficiency of switchable transformers.
H6 Transformer less Topology and Its Modulation Strategy for Mitigating Cm Cu...IJERA Editor
MATLABbasedsingle-phase three-level topology for a transformer less photovoltaic system is presented in this paper. Compared with the conventional H-bridge topology, it only needs two additional asymmetrically distributed switches, and the system common-mode voltage can be kept constant with a simple modulation scheme. Family of H6 transformer less inverter topologies with low leakage currents is proposed and highly efficient and reliable inverter concept (HERIC) topology is also presented in this paper. The proposed inverter can also operate with high frequency by retaining high efficiency which enables reduced cooling system. Finally, the proposed new topology is simulated by MATLAB/Simulink software to validate the accuracy of the theoretical explanation.
The Impact of Line Resistance on the Performance of Controllable Series Compe...Editor Jacotech
In recent years controllable FACTS devices are increasingly
integrated into the transmission system. FACTS devices that
provide series control such as Controllable Series Compensator
(CSC) has significant effect on the voltage stability of Electric
Power system. In this work impact of line resistance on the
performance of CSC in a single-load infinitive-bus (SLIB)
model is investigated. The proposed framework is applied to
SLIB model and obtained results demonstrates that line
resistance has considerable effect on voltage stability limits and
performance of CSC.
This document summarizes a study on using STATCOM and UPFC devices to control power flow in a distribution system. It presents the mathematical models of STATCOM and UPFC, including their control design procedures. Simulation results show that STATCOM effectively regulates local reactive power load and UPFC controls real power flow by varying the phase angle of injected voltage. The study demonstrates how FACTS devices like STATCOM and UPFC can improve power flow control in distribution systems.
International Journal of Engineering Research and DevelopmentIJERD Editor
This document describes a novel bidirectional DC-DC converter that can provide high step-up and step-down voltage gains. It utilizes a coupled inductor with the same number of turns in the primary and secondary windings to achieve these high voltage gains. The steady-state analysis and operating principles of the converter in continuous conduction mode are presented. Simulations in MATLAB are used to verify the performance of the proposed converter and show it can provide constant output voltage when feedback is applied. Compared to a conventional bidirectional DC-DC converter, the proposed design offers higher voltage conversion ratios in both step-up and step-down modes of operation.
Phase shedding in multiphase buck converters to improve the efficiencyIAEME Publication
This document summarizes a research paper that analyzes phase shedding in multiphase buck converters to improve efficiency. The paper simulates a multiphase buck converter with 1, 2, and 3 phases. It finds that using fewer phases at light loads improves efficiency, while more phases are needed at higher loads to reduce ripple. Specifically, 1 phase is most efficient below 0.76A, 2 phases from 0.72A to 1.04A, and 3 phases above 1.04A. Comparing the stages, efficiency increases from 82.01% to 97.57% as load and number of phases increases. Therefore, phase shedding allows a multiphase converter to automatically adjust the number of active phases
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
The document presents a simple algorithm for distribution system load flow analysis that can accommodate distributed generation. It begins by outlining the objectives, motivation and special features of distribution networks that require modified load flow analysis. It then describes the proposed forward-backward sweep method and models for loads and distributed generation. The algorithm is tested on three test systems and results show reductions in losses and improved voltage profiles with distributed generation integrated using the proposed method and models.
A New Filtering Method and a Novel Converter Transformer for HVDC System.IOSR Journals
This document presents a new filtering method and converter transformer design for HVDC systems. The new design aims to address issues with traditional converter transformers and passive filtering methods, such as additional harmonic losses and difficulties meeting insulation requirements.
The new converter transformer uses a prolonged-delta winding configuration and phase shifts of 15 degrees to provide 12-phase commutation voltages. It also employs an inductive filtering mechanism where a tap connects the prolonged and common windings to an LC resonance circuit. This allows harmonic currents to balance out so no inductive harmonics flow in the primary winding.
Simulation results show the new design greatly reduces harmonic content and transformer losses compared to traditional designs. The primary current waveform has lower distortion and THD with the
H6 Transformer less Topology and Its Modulation Strategy for Mitigating Cm Cu...IJERA Editor
MATLABbasedsingle-phase three-level topology for a transformer less photovoltaic system is presented in this paper. Compared with the conventional H-bridge topology, it only needs two additional asymmetrically distributed switches, and the system common-mode voltage can be kept constant with a simple modulation scheme. Family of H6 transformer less inverter topologies with low leakage currents is proposed and highly efficient and reliable inverter concept (HERIC) topology is also presented in this paper. The proposed inverter can also operate with high frequency by retaining high efficiency which enables reduced cooling system. Finally, the proposed new topology is simulated by MATLAB/Simulink software to validate the accuracy of the theoretical explanation.
The Impact of Line Resistance on the Performance of Controllable Series Compe...Editor Jacotech
In recent years controllable FACTS devices are increasingly
integrated into the transmission system. FACTS devices that
provide series control such as Controllable Series Compensator
(CSC) has significant effect on the voltage stability of Electric
Power system. In this work impact of line resistance on the
performance of CSC in a single-load infinitive-bus (SLIB)
model is investigated. The proposed framework is applied to
SLIB model and obtained results demonstrates that line
resistance has considerable effect on voltage stability limits and
performance of CSC.
This document summarizes a study on using STATCOM and UPFC devices to control power flow in a distribution system. It presents the mathematical models of STATCOM and UPFC, including their control design procedures. Simulation results show that STATCOM effectively regulates local reactive power load and UPFC controls real power flow by varying the phase angle of injected voltage. The study demonstrates how FACTS devices like STATCOM and UPFC can improve power flow control in distribution systems.
International Journal of Engineering Research and DevelopmentIJERD Editor
This document describes a novel bidirectional DC-DC converter that can provide high step-up and step-down voltage gains. It utilizes a coupled inductor with the same number of turns in the primary and secondary windings to achieve these high voltage gains. The steady-state analysis and operating principles of the converter in continuous conduction mode are presented. Simulations in MATLAB are used to verify the performance of the proposed converter and show it can provide constant output voltage when feedback is applied. Compared to a conventional bidirectional DC-DC converter, the proposed design offers higher voltage conversion ratios in both step-up and step-down modes of operation.
Phase shedding in multiphase buck converters to improve the efficiencyIAEME Publication
This document summarizes a research paper that analyzes phase shedding in multiphase buck converters to improve efficiency. The paper simulates a multiphase buck converter with 1, 2, and 3 phases. It finds that using fewer phases at light loads improves efficiency, while more phases are needed at higher loads to reduce ripple. Specifically, 1 phase is most efficient below 0.76A, 2 phases from 0.72A to 1.04A, and 3 phases above 1.04A. Comparing the stages, efficiency increases from 82.01% to 97.57% as load and number of phases increases. Therefore, phase shedding allows a multiphase converter to automatically adjust the number of active phases
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
The document presents a simple algorithm for distribution system load flow analysis that can accommodate distributed generation. It begins by outlining the objectives, motivation and special features of distribution networks that require modified load flow analysis. It then describes the proposed forward-backward sweep method and models for loads and distributed generation. The algorithm is tested on three test systems and results show reductions in losses and improved voltage profiles with distributed generation integrated using the proposed method and models.
A New Filtering Method and a Novel Converter Transformer for HVDC System.IOSR Journals
This document presents a new filtering method and converter transformer design for HVDC systems. The new design aims to address issues with traditional converter transformers and passive filtering methods, such as additional harmonic losses and difficulties meeting insulation requirements.
The new converter transformer uses a prolonged-delta winding configuration and phase shifts of 15 degrees to provide 12-phase commutation voltages. It also employs an inductive filtering mechanism where a tap connects the prolonged and common windings to an LC resonance circuit. This allows harmonic currents to balance out so no inductive harmonics flow in the primary winding.
Simulation results show the new design greatly reduces harmonic content and transformer losses compared to traditional designs. The primary current waveform has lower distortion and THD with the
Voltage-current Double Loop Control Strategy for Magnetically Controllable Re...Kashif Mehmood
Voltage regulation depending on reactive power
compensation is the main feature of the AC power supply
system. Magnetically controllable reactors (MCR) are
becoming a growing demand for this purpose. The structure
and working principles of MCR are analysed in this paper
while a simulation model is established. The reactive power
compensation strategy based on a single loop voltage control
system (SLVCS) is presented and a double loop
voltage-current control system (DLVCCS) is proposed. A
comprehensive scenario is developed to mitigate reactive power
compensation by using the proposed controls. Simulation
results substantiate that proposed controls of MCR has a faster
response in comparison to the traditional control, and it
provides the least voltage variation at the line end. It also
shows that the proposed control on MCR meet the desired
objective of the voltage regulation and provides flexibility to ac
transmission system
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.
Voltage profile enhancement in distribution network using static synchronous ...IJECEIAES
STATCOM is one of FACTS devices that used as regulator for transmission and distribution systems which works for reactive power compensation. STATCOM utilisation in distribution system mostly for enhancing the profile of voltage, where used for adjusting the disturbance voltage by injecting into the system a controllable voltage. This paper present a Fuzzy controller based on STATCOM to enhance the voltage profile in distribution network. The controller of STATCOM has simulated for different types of abnormal load conditions of balance and unbalance load. The results of simulation show ability of proposed design to enhance the load voltage which was 96% of the nominal value.
IRJET - Comparison of Different Third Harmonic Injected PWM Strategies for 5-...IRJET Journal
This document compares three third harmonic injected PWM strategies for controlling a 5-level diode clamped inverter: THI-IPD, THI-APOD, and THI-POD. It discusses the inverter topology, describes how a third harmonic is added to the reference signal to increase the fundamental component, and outlines the three modulation strategies. Simulation and experimental results are presented to compare the performance of the strategies in terms of output voltage quality.
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.
The document describes an extended-phase-shift (EPS) control method for isolated bidirectional DC-DC converters used in power distribution for microgrids. EPS control adds an inner phase-shift ratio between switch driving signals in addition to the outer phase-shift ratio of traditional phase-shift control. This decreases the backflow power effect seen in traditional control, expanding the power regulating range and reducing current stress compared to traditional control. The document analyzes the operation principle and eight modes of the converter under EPS control through circuit diagrams and mathematical equations.
Design aspects of high voltage transmission linejournalBEEI
The transmission lines are very important in the transmitted of electrical power, and the process of selecting the voltage of the line is an important task in the design and implementation process. The process of transferring electrical power from one side then onto the next place for long away. While maintaining the percentage regulation within the permissible limits is an important problem in the transfer of energy. In electrical transmission line there are important elements are resistance, inductance and capacitance. The purpose of this paper is to study and calculate economic high-tension voltage and selection of overhead line conductor ACSR.
The document describes the design, simulation, implementation and control of a PLC-based integral cycle controller for resistance spot welding applications. Some key points:
1) An integral cycle controller provides power to a load by passing full voltage cycles on for a set number of cycles, then off for the remaining cycles, varying the duty cycle to control output power.
2) A simulation of an integral cycle controller was developed in MATLAB to analyze output waveforms and harmonic profiles for different duty cycles.
3) The integral cycle controller was designed using a PLC to provide flexible control and implemented for resistance spot welding, which benefits from integral cycle control's ability to minimize harmonics compared to phase control.
The document discusses improving power system performance using Flexible AC Transmission System (FACTS) devices. It describes three types of FACTS devices: Static Var Compensator (SVC), Thyristor Controlled Series Compensator (TCSC), and Unified Power Flow Controller (UPFC). The SVC and TCSC are able to control voltage and improve the voltage profile. Simulations showed adding FACTS devices decreased power losses and improved the voltage level. The UPFC can simultaneously control parameters like line impedance, voltage, and phase angle to regulate power flow.
Analysis of a Single Stage Three Level Converter for a Wind Driven Self Excit...idescitation
The document analyzes a single stage three level converter for a wind driven self excited induction generator. It presents:
1) A model of a three phase single stage three level converter designed for a wind driven self excited induction generator to produce efficient power conversion.
2) Simulation results in MATLAB Simulink showing the generator phase voltage, rectified current, inverted output voltage, and converter output voltage.
3) Hardware prototype results for a 230W system that match the simulation outputs and demonstrate performance for different load values.
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.
This document presents a comparative study of the effects of GCSC (GTO Controlled Series Capacitor) and TCSC (Thyristor Controlled Series Capacitor) on the setting zones of a distance relay protecting a 400 kV transmission line in Algeria. It investigates the modified setting of the forward zones (Z1, Z2, Z3) and reverse zone (Z4) with GCSC and TCSC in capacitive and inductive modes at different firing angles. The study is performed using MATLAB software. Distance relays measure impedance by calculating the ratio of voltage to current. The presence of FACTS devices influences the total impedance seen by the relay, requiring zone settings to be modified to
A Novel Control Strategy of Indirect Matrix Converter Using Space Vector Modu...IJPEDS-IAES
This document presents a novel control strategy for an indirect matrix converter using space vector modulation. The control strategy aims to stabilize frequency variations. It was implemented in MATLAB/Simulink and showed better performance than conventional techniques with lower THD, higher output voltage at the same modulation index, lower switching stress and losses. The complete control strategy including DC link formation, commutation scheme, dwell time calculation and simulation results validating the theoretical analysis are described in the document.
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.
Characteristic and Surge Impedance Variation Impact on Transmission Line Perf...IJECEIAES
Modeling of power systems is essential to perform various network analyses. Voltage regulation, line losses and transmission line efficiency are greatly affected by transmission line parameters. Hence, accurate modeling of transmission line is required. The aim of this paper is to study the impact of characteristic and surge impedances on voltage profile, voltage regulation and transmission line efficiency.
A Review of Matrix Converter and Novel Control Method of DC-AC Matrix Converteridescitation
This paper presents a review of matrix converter and novel control methods for DC-AC matrix converters. It begins with a brief history of matrix converters and discusses different modulation and control strategies that have been developed, including Venturini scalar control, Roy scalar control, carrier-based PWM, and space vector modulation. The paper then proposes a new topology for a DC-AC matrix converter to generate a multilevel output voltage with fewer switches than a traditional multilevel inverter. The performance of the proposed DC-AC matrix converter module is evaluated through MATLAB simulation and by testing with a three-phase induction motor.
El documento habla sobre las propiedades de la piedra lapislázuli y su uso en terapias alternativas. Menciona que la lapislázuli contiene cuarzo, titanio y manganeso que le dan un color rosado a rosa intenso. También describe cómo se pueden usar piedras como la amatista, el citrino y el cuarzo rosa durante sesiones de gemoterapia para equilibrar las energías mentales y físicas y realizar una "cirugía sensible" del corazón. Finalmente, explica que en gemoterap
Galileo Galilei fue un astrónomo y físico italiano que nació en 1564 y murió en 1642. Realizó observaciones del cielo nocturno usando un telescopio que él mismo construyó y descubrió lunas alrededor de Júpiter, la naturaleza de la Vía Láctea y que Venus y Mercurio orbitan el Sol. Además, estableció las bases de la física clásica a través de sus estudios sobre el movimiento y la inercia. Sin embargo, fue juzgado por la
Shakira fue entrevistada por Jaime Baily. La entrevista se centró en la carrera musical de Shakira y sus éxitos recientes. Shakira también habló sobre sus próximos proyectos y planes futuros.
Este documento contiene 21 ejercicios de sistemas de ecuaciones y funciones cuadráticas. El estudiante Iván Darío Montoya Baena en el área de matemáticas del colegio I.E.R. Chaparral debe resolver estos ejercicios como prerrequisito para la evaluación de curso remedial del año 2012. Los ejercicios involucran métodos como sustitución, igualación, comparación de Cramer y resolución gráfica de sistemas de ecuaciones, así como determinación de raíces, vértices
Formadores ante la sociedad de la informacionxochilgarcia
Este documento describe los nuevos roles y responsabilidades de los docentes en la sociedad de la información. Los docentes ahora deben poseer competencias digitales para aprovechar las tecnologías de la información y la comunicación (TIC) en la enseñanza a distancia y el desarrollo de nuevas formas de entender el mundo. También deben diagnosticar las necesidades de los estudiantes, planificar el currículo, diseñar estrategias de enseñanza y aprendizaje, y evaluar los resultados obtenidos por los estudiantes.
Voltage-current Double Loop Control Strategy for Magnetically Controllable Re...Kashif Mehmood
Voltage regulation depending on reactive power
compensation is the main feature of the AC power supply
system. Magnetically controllable reactors (MCR) are
becoming a growing demand for this purpose. The structure
and working principles of MCR are analysed in this paper
while a simulation model is established. The reactive power
compensation strategy based on a single loop voltage control
system (SLVCS) is presented and a double loop
voltage-current control system (DLVCCS) is proposed. A
comprehensive scenario is developed to mitigate reactive power
compensation by using the proposed controls. Simulation
results substantiate that proposed controls of MCR has a faster
response in comparison to the traditional control, and it
provides the least voltage variation at the line end. It also
shows that the proposed control on MCR meet the desired
objective of the voltage regulation and provides flexibility to ac
transmission system
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.
Voltage profile enhancement in distribution network using static synchronous ...IJECEIAES
STATCOM is one of FACTS devices that used as regulator for transmission and distribution systems which works for reactive power compensation. STATCOM utilisation in distribution system mostly for enhancing the profile of voltage, where used for adjusting the disturbance voltage by injecting into the system a controllable voltage. This paper present a Fuzzy controller based on STATCOM to enhance the voltage profile in distribution network. The controller of STATCOM has simulated for different types of abnormal load conditions of balance and unbalance load. The results of simulation show ability of proposed design to enhance the load voltage which was 96% of the nominal value.
IRJET - Comparison of Different Third Harmonic Injected PWM Strategies for 5-...IRJET Journal
This document compares three third harmonic injected PWM strategies for controlling a 5-level diode clamped inverter: THI-IPD, THI-APOD, and THI-POD. It discusses the inverter topology, describes how a third harmonic is added to the reference signal to increase the fundamental component, and outlines the three modulation strategies. Simulation and experimental results are presented to compare the performance of the strategies in terms of output voltage quality.
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.
The document describes an extended-phase-shift (EPS) control method for isolated bidirectional DC-DC converters used in power distribution for microgrids. EPS control adds an inner phase-shift ratio between switch driving signals in addition to the outer phase-shift ratio of traditional phase-shift control. This decreases the backflow power effect seen in traditional control, expanding the power regulating range and reducing current stress compared to traditional control. The document analyzes the operation principle and eight modes of the converter under EPS control through circuit diagrams and mathematical equations.
Design aspects of high voltage transmission linejournalBEEI
The transmission lines are very important in the transmitted of electrical power, and the process of selecting the voltage of the line is an important task in the design and implementation process. The process of transferring electrical power from one side then onto the next place for long away. While maintaining the percentage regulation within the permissible limits is an important problem in the transfer of energy. In electrical transmission line there are important elements are resistance, inductance and capacitance. The purpose of this paper is to study and calculate economic high-tension voltage and selection of overhead line conductor ACSR.
The document describes the design, simulation, implementation and control of a PLC-based integral cycle controller for resistance spot welding applications. Some key points:
1) An integral cycle controller provides power to a load by passing full voltage cycles on for a set number of cycles, then off for the remaining cycles, varying the duty cycle to control output power.
2) A simulation of an integral cycle controller was developed in MATLAB to analyze output waveforms and harmonic profiles for different duty cycles.
3) The integral cycle controller was designed using a PLC to provide flexible control and implemented for resistance spot welding, which benefits from integral cycle control's ability to minimize harmonics compared to phase control.
The document discusses improving power system performance using Flexible AC Transmission System (FACTS) devices. It describes three types of FACTS devices: Static Var Compensator (SVC), Thyristor Controlled Series Compensator (TCSC), and Unified Power Flow Controller (UPFC). The SVC and TCSC are able to control voltage and improve the voltage profile. Simulations showed adding FACTS devices decreased power losses and improved the voltage level. The UPFC can simultaneously control parameters like line impedance, voltage, and phase angle to regulate power flow.
Analysis of a Single Stage Three Level Converter for a Wind Driven Self Excit...idescitation
The document analyzes a single stage three level converter for a wind driven self excited induction generator. It presents:
1) A model of a three phase single stage three level converter designed for a wind driven self excited induction generator to produce efficient power conversion.
2) Simulation results in MATLAB Simulink showing the generator phase voltage, rectified current, inverted output voltage, and converter output voltage.
3) Hardware prototype results for a 230W system that match the simulation outputs and demonstrate performance for different load values.
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.
This document presents a comparative study of the effects of GCSC (GTO Controlled Series Capacitor) and TCSC (Thyristor Controlled Series Capacitor) on the setting zones of a distance relay protecting a 400 kV transmission line in Algeria. It investigates the modified setting of the forward zones (Z1, Z2, Z3) and reverse zone (Z4) with GCSC and TCSC in capacitive and inductive modes at different firing angles. The study is performed using MATLAB software. Distance relays measure impedance by calculating the ratio of voltage to current. The presence of FACTS devices influences the total impedance seen by the relay, requiring zone settings to be modified to
A Novel Control Strategy of Indirect Matrix Converter Using Space Vector Modu...IJPEDS-IAES
This document presents a novel control strategy for an indirect matrix converter using space vector modulation. The control strategy aims to stabilize frequency variations. It was implemented in MATLAB/Simulink and showed better performance than conventional techniques with lower THD, higher output voltage at the same modulation index, lower switching stress and losses. The complete control strategy including DC link formation, commutation scheme, dwell time calculation and simulation results validating the theoretical analysis are described in the document.
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.
Characteristic and Surge Impedance Variation Impact on Transmission Line Perf...IJECEIAES
Modeling of power systems is essential to perform various network analyses. Voltage regulation, line losses and transmission line efficiency are greatly affected by transmission line parameters. Hence, accurate modeling of transmission line is required. The aim of this paper is to study the impact of characteristic and surge impedances on voltage profile, voltage regulation and transmission line efficiency.
A Review of Matrix Converter and Novel Control Method of DC-AC Matrix Converteridescitation
This paper presents a review of matrix converter and novel control methods for DC-AC matrix converters. It begins with a brief history of matrix converters and discusses different modulation and control strategies that have been developed, including Venturini scalar control, Roy scalar control, carrier-based PWM, and space vector modulation. The paper then proposes a new topology for a DC-AC matrix converter to generate a multilevel output voltage with fewer switches than a traditional multilevel inverter. The performance of the proposed DC-AC matrix converter module is evaluated through MATLAB simulation and by testing with a three-phase induction motor.
El documento habla sobre las propiedades de la piedra lapislázuli y su uso en terapias alternativas. Menciona que la lapislázuli contiene cuarzo, titanio y manganeso que le dan un color rosado a rosa intenso. También describe cómo se pueden usar piedras como la amatista, el citrino y el cuarzo rosa durante sesiones de gemoterapia para equilibrar las energías mentales y físicas y realizar una "cirugía sensible" del corazón. Finalmente, explica que en gemoterap
Galileo Galilei fue un astrónomo y físico italiano que nació en 1564 y murió en 1642. Realizó observaciones del cielo nocturno usando un telescopio que él mismo construyó y descubrió lunas alrededor de Júpiter, la naturaleza de la Vía Láctea y que Venus y Mercurio orbitan el Sol. Además, estableció las bases de la física clásica a través de sus estudios sobre el movimiento y la inercia. Sin embargo, fue juzgado por la
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This document discusses a transformer-less approach for series and shunt compensation using a cascaded multilevel inverter. The key points are:
1) A cascaded multilevel inverter arrangement with H-bridge cells is used for reactive power compensation without using a transformer between the series and shunt converters. This eliminates issues associated with using transformers such as cost, size, losses and response time.
2) The series converter controls voltage to regulate active and reactive power flow while the shunt converter controls current to compensate for any active power flow between the converters. This ensures no active power is exchanged so no transformer is needed.
3) Control methods for the shunt voltage and series current compensation use PI controllers
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
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.
IRJET- A Review on Three-Phase to Seven-Phase Power Converter using TransformerIRJET Journal
This document proposes and discusses a technique to generate a seven-phase power supply from a standard three-phase supply using a special transformer connection scheme. The transformer has three iron cores each with one primary and multiple secondary coils. By connecting the secondary coils in a specific configuration based on turn ratios, a seven-phase star output is obtained where each phase is 51.43 degrees out of phase. This technique allows generation of a pure sinusoidal seven-phase voltage that can be used for multiphase motor testing or in seven-phase power transmission and rectifier systems. Mathematical analysis is provided to derive the turn ratios needed to produce the seven evenly spaced phases from the three input phases.
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based three phase Induction Heating applications.
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Different type s of power converters fed relutanceSambit Dash
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Analysis of a Quasi Resonant Switch Mode Power Supply for Low Voltage Applica...IDES Editor
QRC provides efficient and regulated switch mode
power supplies for robotic and satellite applications. This paper
addresses the enhanced controller techniques for high
frequency isolation based push-pull Quasi Resonant
Converter. This technique is similar to the conventional PI
controller technique but varies only the enhancement
constants to improve the time domain response of the
converter. The proposed converter is designed for low output
voltage and power rating, characteristically 5V and 5 W, with
the comprehension of current design trends towards enhanced
performance. At the primary stage, to validate the design of
the converter, simulation is performed in PSIM for ±50% load
variations. A prototype model of this converter is developed.
The results obtained from the experimental set-up are
presented and analysed in detail. The results reveal the
superiority of the proposed method.
Analysis of a Quasi Resonant Switch Mode Power Supply for Low Voltage Applica...
Group 1,6
1. European Association for the
Development of Renewable Energies,
Environment and Power Quality
International Conference on Renewable Energies and Power
Quality (ICREPQ’09)
Valencia (Spain), 15th to 17th April, 2009
Development of Switchable Transformer Research
at University of South Australia
H. A. Dharmawan1
and S. A. M. Ali2
1
School of Electrical and Information Engineering
University of South Australia, Adelaide, South Australia 5095
Phone/Fax number: +61-8-83023346/+61-8-83023384, e-mail: dhaha001@students.unisa.edu.au
2
School of Electrical and Information Engineering
University of South Australia, Adelaide, South Australia 5095
Phone/Fax number: +61-8-83023346/+61-8-83023384, e-mail: Sam.Ali@unisa.edu.au
Abstract. This paper describes research development focusing
on the designs of switchable transformers and their control system
at University of South Australia. Research development of
switchable transformer has become one of the major research
interests in school of Electrical and Information Engineering,
University of South Australia since year 2000. Research in this
area has been carried out through undergraduate to post graduate
studies. Several transformer designs, starting from the rating of
1kVA to 10kVA, have been introduced. Testing results from the
designs have shown the improvement of the transformer
efficiency during low or high loads. As the switchable
transformers utilize several switching devices that need to be
synchronously controlled, research on the development of the
switchable transformer control systems has also been carried out.
Now, in this school, a study of utilizing controller area network
(CAN) as media to integrate modules in the control system is
done. The study also focused on the remote monitoring and
control system of the switchable transformer through a local area
network (LAN).
Key words
Switchable transformer, Energy efficient, Research
development.
1. Introduction
Switchable transformers are newly introduced types of
transformer featuring several winding configurations that
can be altered based on the variation of the loads[1]. Unlike
windings in normal or conventional transformers which
have fixed number of turns in their primary and secondary,
winding configurations in switchable transformers provide
higher number of turns for low loads and lower number of
turns for high loads. Through these configuration
implementations, amount of losses can be kept less than
that of fixed number of windings. In other words,
switchable transformers have higher efficiency than
conventional transformers have. A design strategy to
increase the number of turns in low loads is to provide
extra turns of windings and this is referred to as series
configurations. On the other hand, to lower the number of
turn in high loads, some portions of turns of windings are
configured in parallel and this is referred to as parallel
configurations.
Figure 1 and 2 provide an example of how efficiency of a
conventional transformer improved through utilization of a
series winding configuration below 0.5 p.u. and parallel
winding configuration above 0.6 p.u.[2]. The point of load
where the winding configuration should be switched from
series to parallel or vice versa is called switching point of
switchable transformers. In this example the switching
point is between 0.5-0.6 p.u. These graphs were visualized
from losses measurement results through open and short
circuit tests of a single-phase 1kVA switchable distribution
transformer built in 2000.
Fig. 1. Comparison of total losses of 1kVA conventional
and switchable transformer[2].
0
10
20
30
40
50
60
0.00 0.20 0.40 0.60 0.80 1.00 1.20
TotalLosses(Watts)
Load (p.u.)
Conventional
Series
Parallel
2. Fig. 2. Comparison of efficiency of 1kVA conventional
and switchable transformer[2].
2. Initial Studies of Switchable Transformer
In 2000, through postgraduate study, a small single phase
1kVA switchable distribution transformer was designed
and built in the school, with primary and secondary
voltages of 415V and 240V respectively, using a uni-core
shell-type configuration[2]. In the design process,
techniques and calculations used were not far different with
those for conventional transformers. The essential
differences were the use of lower flux density at low loads
and lower winding resistances at high loads through certain
arrangement of tappings of windings in the switchable
transformer. As can be seen from Fig. 3, the primary and
secondary windings were made up of several tappings of
the transformer which were connected through three
switching devices (S1, S2 and S3) for both windings.
Fig. 3. Tappings of the 1 kVA switchable transformer[2].
(Three tappings for each primary and secondary windings:
420, 140, 25+115, 248, 82, 13+69)
Table 1 summaries the characteristics of the transformer for
the different configurations. It can be seen from this table
the use of lower flux density (1.43T) for series
configuration with the consequence of increasing the
winding resistances. When this configuration is applied at
low loads, the lower flux density provides lower core
losses. As the core losses are dominant in low loads, the
total losses will be less, although the winding resistances
increase and cause more copper losses. On the other hand,
the use of lower number of turns through parallel
configuration will reduce copper losses which are dominant
at high loads. Again, this will reduce total losses of the
transformer at high loads. Using data from measurement
results of open and short circuit tests, the losses and
efficiency of the transformer configured in conventional,
series and parallel are visualized in Figure 1 and 2.
Figure 4 shows the 1 kVA transformer that was built and
tested in 2000. A view of application software made and
used in the design process of this transformer can be seen
from Figure 5. This software reduced complication tasks in
designing the transformer that included calculations and
modifications. The design was in fact not straightforward
and needed to perform some simulations to determine the
best result. This application was however intended for only
designs of switchable transformers having power rating up
to 5 kVA [2]. Through this application, users can enter
specifications such as power rating, input & output voltage,
flux density, core type etc. in the specification section (see
Figure 5 on the left column). After running the calculation,
the program will show the summary of data as the results
(see Figure 5 on right column). Users can scroll the
window of the result in order to view the next parameters in
this column. Setting for winding configurations, i.e
conventional, series and parallel, is entered through the
options section. Furthermore, percentage of additional turns
in series configurations and percentage of turns which will
be configured in parallel can also be set in this section. In
designing the 1 kVA switchable transformer, the best
configuration of tappings for series and parallel
configurations was mainly chosen based on the efficiency
performances that could be seen through the efficiency
figures which were generated automatically after running
the calculation.
As additional design guide for further design of switchable
transformers, the following limitations are mentioned in
reference [2]:
1. Extra turns in series configuration windings will take
more space compared to conventional windings. The
design should be taken care of so that there will be
sufficient window space left after installing whole
turns.
2. As the lower number of turns in parallel configuration
causes an increase in flux density, the design should
makes sure that the flux density is still below its
saturation region.
Table 1. Characteristic of the 1 kVA transformer[2].
Configuration
Number
of Turns
Flux
Density
(T)
Measured
Winding
Res. ( )
Switching
Devices
Status
Pri. Sec. Pri. Sec. S1 S2 S3
Series 700 412 1.43 2.44 1.44 off on off
Conventional 585 343 1.72 1.97 1.13 off on off
Parallel 560 330 1.80 1.70 1.01 on off on
Pri.: Primary, Sec.: Secondary.
90
91
92
93
94
95
96
97
98
0.00 0.20 0.40 0.60 0.80 1.00 1.20
Efficiency(%)
Load (p.u.)
Conventional
Series
Parallel
3. A1
A2
A3
A4
A5
A6
A7
A8
A16
A15
A14
A13
A12
A11
A10
A9
Top View
Fig. 4. The 1 kVA transformer built and tested in 1999[2].
Fig. 5. Switchable transformer design software[2].
The design of the switchable transformer was continued up
to year 2001, where a three-phase switchable transformer
was constructed using three single-phase switchable
transformers. Figure 6 shows the connection of th
transformer and its measurement setup. In the experiment,
a three-phase power supply and variable load were
connected to the transformer. While applying variable
loads, current and voltage signals were recorded through
DAQ interface in a personal computer for analysis
240V
Phase A
Phase B
Phase C
Ground
3PH Power Supply
415V, 50 Hz
3PH Switchable
Transformer
415V
A
Current
Sensor
V
A
Current
Sensor
Current
Sensor
Primary Secondary
Voltmeter
Amperemeter
DAQ
interface
Phase A
Phase C
Phase B
V
Fig. 6. Measurement setup of the three-
switchable transformer.
Primary
Terminals
Secondary
Terminals
Secondary
Windings
Primary
Windings
Core
The 1 kVA transformer built and tested in 1999[2].
. Switchable transformer design software[2].
The design of the switchable transformer was continued up
phase switchable transformer
phase switchable
shows the connection of this
. In the experiment,
phase power supply and variable load were
While applying variable
urrent and voltage signals were recorded through
for analysis.
W
Wattmeter
Three
voltage
transfor-
mers
3PH
Variable
Load
-phase
Moreover in this year, a microcontroller is provided to
control the switching devices in order to achieve smooth
switching process of the switching devices[
secondary voltages as well as currents were sensed and
passed through ADC to the microcontroller. The
microcontroller provided triggers to the intended switching
devices, based on the configuration that should be used.
Eighteen SSRs (see Figure 7) were used for the switching
devices and controlled synchronously by the
microcontroller. As presented in [3], the smooth switching
process from series to parallel configuration or vice versa
could be made possible through the utilization of the
microcontroller.
Fig. 7. The switching devices for the three
switchable transformer used in 2000
3. Further Development of
Transformer
Since year 2000 then, switchable transformers become
major research interests in school of Electrical
Information Engineering, University of South Australia,
and in 2002, a three-phase 3 kVA
transformer was designed and built.
transformer can be seen from Fig
research on optimizing the design of the switchable
transformer was also done and focused on modeling the
magnetic flux in the transformer using Finite Element
Analysis (FEA) software, i.e.
Analysis Ltd.[4]. By using this software, magnetic
density in transformer’s cores can be visualized at any
moment in time. Research on optim
cores was carried out by simulating
configurations, performing geometrical adjustment
comparing the results visualized by the software.
As the research on switchable transformers continue
2003 a three-phase 10 kVA switchable transformer was
also built; see Figure 8b. The design was optimized through
the use of the FEA software. Figure
for the 3 kVA and 10 kVA switchable transformers
basically had the same manner of configurations as the
previous 1 kVA switchable transformer
these transformers are presented in Table
results from these transformers
n this year, a microcontroller is provided to
control the switching devices in order to achieve smooth
switching process of the switching devices[3]. Primary and
secondary voltages as well as currents were sensed and
passed through ADC to the microcontroller. The
microcontroller provided triggers to the intended switching
devices, based on the configuration that should be used.
were used for the switching
devices and controlled synchronously by the
microcontroller. As presented in [3], the smooth switching
process from series to parallel configuration or vice versa
could be made possible through the utilization of the
ing devices for the three-phase
switchable transformer used in 2000.
of Switchable
, switchable transformers become
school of Electrical and
Engineering, University of South Australia,
kVA switchable distribution
designed and built. Photo of this
transformer can be seen from Figure 8a. During this time,
on optimizing the design of the switchable
transformer was also done and focused on modeling the
magnetic flux in the transformer using Finite Element
e. Quickfield from Tera
. By using this software, magnetic flux
can be visualized at any
ptimization of transformer’s
by simulating the effects of winding
eometrical adjustments and
isualized by the software.
As the research on switchable transformers continued, in
phase 10 kVA switchable transformer was
The design was optimized through
Figure 9 shows tappings used
for the 3 kVA and 10 kVA switchable transformers which
basically had the same manner of configurations as the
previous 1 kVA switchable transformer. Specifications of
these transformers are presented in Table 2 and 3. Testing
rom these transformers also showed that higher
4. efficiency performance can be achieved through their series
and parallel configurations.
(a) (b)
Fig. 8. The three-phase switchable transformers:
(a) 3 kVA built in 2002 (b) 10 kVA built in 2003.
(a)
(b)
Fig. 9. The tappings of windings of the three-phase switchable
transformers: (a) 3 kVA built in 2002 (b) 10 kVA built in 2003.
Table 2. Characteristic of the 3 kVA transformer[7].
Config.
Number
of Turns
Flux
Density
(T)
Measured
Winding Res. ( )
Pri. Sec. Pri. Ph1,2,3 Sec. Ph1,2,3
Series 520 300 1.28 1.43, 1.44, 1.44 0.60, 0.60, 0.60
Conv. 433 250 1.55 1.15, 1.15, 1.16 0.48, 0.49, 0.49
Parallel 407 235 1.64 0.92, 0.93, 0.93 0.39, 0.39, 0.39
Pri. Ph1,2,3: Primary Phase 1, 2 & 3.
Sec. Ph1,2,3: Secondary Phase 1, 2 & 3.
Table 3. Characteristic of the 10 kVA transformer[4].
Config.
Number
of Turns
Flux
Density
(T)
Measured
Winding Res. ( )
Pri. Sec. Pri. Ph1,2,3 Sec. Ph1,2,3
Series 214 124 1.17 0.30, 0.30, 0.30 0.10, 0.09, 0.09
Conv. 178 103 1.41 Not Available Not Available
Parallel 161 93 1.55 0.18, 0.18, 0.18 0.06, 0.05, 0.05
Pri. Ph1,2,3: Primary Phase 1, 2 & 3.
Sec. Ph1,2,3: Secondary Phase 1, 2 & 3.
Not long after the 10kVA switchable transformer was built,
some studies (including postgraduate and undergraduate
studies) on development of a data acquisition for analyzing
performances of the transformer were conducted. One of
the studies utilizes a 16-bit PIC microcontroller as
embedded processor. Besides controlling the transformer,
through its built-in digital signal processing (DSP) engine,
the microcontroller performed FFT calculations to retrieve
harmonic contents in the primary and secondary voltages
and current signals. This microcontroller then sent acquired
and processed data to a PC through an RS232 connection.
A DAQ hardware and LabView from National Instrument
were combined to provide comparison in monitoring the
performances of the transformer.
Recently, in 2005, a study on the implementation of an
adaptive fuzzy logic controller using executable
heterogeneous model was conducted. This model was
intended to integrate the environmental, loading and
electrical parameters of the switchable transformers[5][6].
Through the use of fuzzy logic controller, more optimized
control could be expected. As the research continues, more
complications arise in the control system such as the
requirement for fast calculations, better user interface and
communication. These complicated tasks are difficult to
perform by using one microcontroller as implemented in
the previous control systems. More reliable designs with
reduced wirings are also expected.
A new idea is then proposed through post graduate study
and used as further development of the control system. The
new idea here is to utilize multi-processor and controller
area network (CAN) in the system. These processors are
programmed to perform fast acquisition, calculations, send
triggers and synchronize on/off operations of switching
devices, provide a comprehensive and easy user interface
and provide a reliable way of communicating to a server.
The controller area network is chosen as media to integrate
the processors which are separated through some modules
in the control system. CAN is considered to be used
because it is widely used in industries, low-cost (by using
only two wires) and provides reliable serial transmission
through its sophisticated error detection and robust error
handling mechanisms. Furthermore, CAN also immunes to
electromagnetic interference.
5. Figure 10 shows the current control system of switchable
transformer. The embedded controller is divided into
several modules: high current controller, data acquisition
(DAQ) for phase 1, 2 & 3 and user interface & RTU. The
high current controller provides synchronized triggers to
the 18 switching devices that connect the tappings of
windings of the transformer. These switching devices are
turned on/off based on the information that is directly sent
by the three DAQ modules through CAN bus. Data
processing, such as FFT calculation, is carried out in the
DAQ modules. Beside transmitting the acquired parameters
and processed data (temperature, voltages and currents) to
the high current controller module and to the user interface
& RTU module, the DAQ modules provide exchange
information between them self. The user interface module
& RTU module provides easy user interface to operators
and connection to a server. The server can also get direct
access to all the modules through CAN bus. Some client
and server applications are developed to enable remote
monitoring and control through the local area network
(LAN) in the school.
Fig. 10. Current control system of switchable transformer
4. Conclusion
Switchable transformers have become one of major
research interests in school of Electrical and Information
Engineering, University of South Australia since year 2000.
Attempts have been made to provide better designs with
higher power rating of switchable transformers and
enhance reliability of the control system of the switchable
transformers. Testing results have shown that the
switchable transformers provide better characteristic in
terms of efficiency performances during low or high loads.
This promises acceptance of using the switchable
transformers in industries.
5. Refferences
[1] Ali, S.A.M. & Dharmawan, H. A., "Energy Efficient
Switchable Transformer", Applied Electromagnetics and
Mechanics: Proceedings of the 10th International
Symposium on Applied Electromagnetics and Mechanics,
2001, pp.29-30, Japan (T Takagi, M Uesaka, Eds).
[2] Dharmawan, H. A., “Micro-controlled Energy Efficient
Switchable Transformer”, Masters Thesis, University of
South Australia, 2001.
LOCAL
AREA
NETWORK
MICROCONTROLLER
CAN CONTROLLER
CAN TRANSCEIVER
Drivers &
Oupto-couplers
UserInterface,
RTU
MICROCONTROLLER
CAN CONTROLLER
CAN TRANSCEIVER
18 Swicting Devices
RS232
THREE-PHASE SWITCHABLE TRANSFORMER
HighCurrentControler
DAQPhase1
PROCESSOR DSP
CAN CONTROLLER
CAN TRANSCEIVER
Signal Conditioning
2 VTs & 2 CTs
Primary &
Secondary
Lines
Serial
Temp.
Sensors
I2
C
PHASE 1
DAQPhase2
PROCESSOR DSP
CAN CONTROLLER
CAN TRANSCEIVER
Signal Conditioning
2 VTs & 2 CTs
Primary &
Secondary
Lines
Serial
Temp.
Sensors
I2
C
PHASE 2
DAQPhase3
PROCESSOR DSP
CAN CONTROLLER
CAN TRANSCEIVER
Signal Conditioning
2 VTs & 2 CTs
Primary &
Secondary
Lines
Serial
Temp.
Sensors
I2
C
PHASE 3
EMBEDDED
CONTROLLER
Buttons
Keypad
LCD
LEDs
CAN Interface
CAN BUS
SERVER CLIENT Remote Monitoring
and Control
18 3 3 3
6. [3] Dharmawan, H. A. & Ali, S.A.M., "Design of Switchable
Transformer Control System Employing the Micro-
controller 80C552", International Journal of Applied
Electromagnetics and Mechanics, Japan, Vol. 13 (2002) pp.
99-106 ISBN 1 58603 3271.
[4] Kelly, G. B., “Flux Modelling and Optimisation of 3 Phase
Transformers using Finite Element Analysis”, Project
Report, University of South Australia, 2003.
[5] Kiefer, R. H & Ali, S.A.M. “ Heterogeneous Modeling of an
Intelligent Switchable Energy Efficient Distribution
Transformer Inclusive of Environmental and Loading
Conditions”, Proceedings, ICIS 2005 (International
conference on intelligent systems Kuala Lumpur, Malaysia
1-3 December 2005, pp 1-6.
[6] Kiefer, R. H & Ali, S.A.M. “Executable Heterogeneous
Model of an Adaptive Fuzzy Logic Controller and
Switchable Energy Efficient Distribution Transformer”,
ICEM-06 (International conference on electrical machines),
Crete Island Greece, 2-5 September 2006.
[7] Ali, S.A.M & Smith, J.K.E “The Practical design and
application of a three phase, 3 kVA, energy efficient
distribution transformer”, Journal of Applications of
Electromagnetic Phenomena in Electrical and Mechanical
Systems” JSAEM and Kanazawa University, Japan, 2003,
pp. 307-314.
[8] Ali, S.A.M, & Klaer D. “Design & Implementation of a 3-
Phase Energy Efficient Switchable Transformer Controller
Using the PIC Microcontroller 18F8720”, 2004
International conference on power system technology, 21-
24 November 2004, Singapore, pp.1-6.
[9] Ali, S.A.M & Pham, H., “Design and Implementation of
Smart PIC Micro-controlled 3–Phase Energy Efficient
Distribution Transformer”, Proceedings of 15th Symposium
on Electromagnetics and Dynamics, 28-30 May 2003,
Kanazawa Japan, pp 327-330.
[10] Ali, S.A.M & Pham, H., “Testing and Evaluation of a 3–
Phase, 3 kVA Energy Efficient Distribution Transformer”,
Proceedings of 15th Symposium on Electromagnetics and
Dynamics,28-30 May 2003, Kanazawa, Japan, pp.323-325.
[11] Kiefer, R. H & Ali, S.A.M. ”Three-Phase Switchable
Distribution Transformers: Economics, Plus a Fuzzy Logic
Control and Condition Monitoring System”, The Third
IASTED International Conference on Power and Energy
Systems, 3-5 September 2003, Marbella, Spain, pp.516-520.