EPE Association: EPE-PEMC 2008 - Topic: Related Topics

EPE-PEMC 2008 - Topic: Related Topics
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2008 - Conference > EPE-PEMC 2008 - Topic: Related Topics

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   Determination of the Characteristic Life Time of Paper-Insulated MV-Cables Based on a Partial Discharge and tan(δ) Diagnosis
By I. Mladenovic [View]
[Download]

Abstract: Monitoring the condition of electrical equipment insulation by means of partial discharge measurement and analysis is an effective diagnostic tool for the prediction of service failures. In this paper an accelerated aging system specialized for paper insulated lead covered (PILC) cables, with a highly sensitive and selective PD-detection/localization and tan(δ) measurement is presented. It facilitates the monitoring of the entire aging process and the later development of sophisticated diagnostic criteria based on the physical aging process.

   DQ-Transformation Approach for Modelling and Stability Analysis of AC-DC Power System with Controlled PWM Rectifier and Constant Power Loads
By K-N Areerak, S. V. Bozhko, G. M. Asher and D. W. P. Thomas [View]
[Download]

Abstract: In this paper a technique for analysing aircraft frequency wild power systems with constant power loads is developed and demonstrated. Power electronic based loads often behave as constant power loads, especially when feeding machine or actuator drives under current and speed control. The constant power (CP) loads can affect the stability of the power system. The problem is a particular issue in aircraft power systems as the proportion of CP loads increases with the advent of the more-electric aircraft. This paper deals with stability analysis of a three-phase frequency-wild AC power system with a CP load fed through a vector-controlled front-end PWM converter. The mathematical model suitable for stability analysis is derived using the DQ-transformation method. It is shown how the proposed approach can be applied to study the power system behaviour under different loads and parameters variations, as well as to assess the power system stability margins. The study is supported by intensive simulations that verify the reported theoretical results.

   Elimination of Increased Excitation of Common-Mode Oscillations in Electrical Drive Systems with Active Front End and Long Motor Cables
By Thomas Weidinger [View]
[Download]

Abstract: In this paper the analysis of common-mode oscillations in electrical drive systems is presented. The analysed oscillations occur especially in electrical drive systems with active front end, common DC link and long motor cables. Because of resonant frequencies at 10 to 40 kHz low damping occurs. Some motors with concentrated winding show resonant behaviour in this frequency range and increase the overvoltages from the terminals to the star point. For example a torquemotor is analysed and modelled. In the concerned frequency range switching operations generate a significant excitation. As the focus of this paper a special coupling mechanism is described. This mechanism enforces the excitation by the switching of the active front end. Afterwards remedies are analysed. Simulations and measurements on sample systems with and without remedies show apparent voltage stressing of motors, common-mode losses and currents that disturb the drive system.

   Estimation of the Untapped Regenerative Braking Energy in Urban Electric Transportation Network
By Leonards Latkovskis [View]
[Download]

Abstract: The paper presents an estimation of the reserves of untapped regenerative braking energy in the power supply network of urban electric transport. The estimation is made by a method based on probabilistic principles, transport timetable and measured power diagrams. The amount of unused regenerative energy is calculated for two substations in the electric transport network in Riga, with power measurement technique described for T3A tramcars. The results of the work allow calculation of economical aspects of the regenerative braking energy utilization not only for the current situation but also for future, taking into account growth in the transport fleet and changes in its organization.

   Genetic Identification of Parameters the Sandwich Piezoelectric Ceramic Transducers for Ultrasonic Systems
By Pawel Fabijanski [View]
[Download]

Abstract: In this paper the genetic algorithm is used to optimization of parameters the equivalent electrical circuit of piezoelectric ceramic. Sandwich type piezoelectric ceramic transducer are the source of power ultrasounds when the vibration is activated by a voltage inverter. The output frequency of inverter most by equals the mechanical resonance frequency of the transducer and most by tuning with very high precise. In real circuits the mechanical resonant frequency is function of many parameters of piezoelectric material. The equivalent electrical circuit of transducer transforms this parameters in electrical value. This electrical circuit consist of connection in parallel: Co end RLC elements and this units are part of the oscillating circuit of inverter. The values of equivalent electrical circuit varies during the operation of transducer in function extending parameters, among others, the most important are temperature and time. In this situation to obtain the optimal value of the output voltage frequency of inverter most by know electrical parameters equivalent circuit of transducer. In the resolution of difficult problems to by effective the genetic algorithm.

   Implementation of a Virtual Laboratory for Low Power Electrical Drives
By Gh. Baluta [View]
[Download]

Abstract: E-learning has introduced new opportunities in teaching and learning electrical engineering subjects. This paper presents the architecture of a virtual engineering laboratory, designed to allow remote training in the control of DC, brushless DC, and stepper servomotors. An example of DC servomotors control on virtual laboratory is also presented.

   Inner Gas Pressure Measurement Based Life-span Estimation of Electrolytic Capacitors
By A. Riz [View]
[Download]

Abstract: As the wide scale usage of aluminum electrolytic capacitors it is very important to be familiar with them. The research and development of new and long sight better capacitors is very essential for circuit designers and costumers in general hence this is a very important issue to deal with. In the presented paper a summarize of the buildup and the useful life of the capacitors and a special procedure for the life-span analysis will be shown. The presentation is also deals with the related part of the Electrolytic Capacitor Measurement System (ECMS) implemented in the Aluminum Electrolytic Capacitor Development Laboratory of EPCOS Electronic Parts and COmponentS, Hungary. The results show, thanks to the introduction of the mentioned system, the efficiency of special measurements like the analysis of the useful life of aluminum electrolytic capacitors have been increased considerably.

   Internal Short Circuit in a Tooth Wound PMSM with Stranded Conductors
By Damien Birolleau [View]
[Download]

Abstract: This paper deals with the modelization of an internal short circuit in a coil of a permanent magnet synchronous motor with a tooth wound stator. It focuses on the simulation of windings made of stranded conductors. The method of modelization is described, validated and applied to a case study. Different configurations of shortcircuits and their consequences are investigated.

   LCL-Load Modular Converter for Induction Heating
By Maciej A. Dzieniakowski [View]
[Download]

Abstract: The paper presents novel resonant converter with LCL load, applied for induction heating. The control structure and power electronics circuit of VS inverter fed medium frequency induction furnace are described. The two resonant load topologies are investigated and applied. The control system assures fully synchronous operation in whole resonant load parameter changes. The control method and proposed converter topology results in resonant load independence on inverter parameters. It allows simple, modular converter construction. The present applications of the system cover range power to 1MW.

   On-Line PID Controller Tuning Using Genetic Algorithm and DSP PC Board
By Pawel Fabijański [View]
[Download]

Abstract: In this paper we uses a software pack, which allows to adjust PID controller automatically in real time way in the case of changes parameters of used object. PID settings are optimized in real time by using genetic algorithm and are compared with generally accepted quality indicators for control systems like rise time, \% overshoot and settling time of step response or such coefficient like oscillations frequency, reduced damping and gain of second order object. A digital signal processor (DSP) is a specialized microprocessor designed specifically for digital signal processing generally in real time applications requiring high computation. The simulation results were verified by some laboratory test.

   Optimal Control: Load Frequency Control of a Large Power System
By Sílvio José Pinto Simões Marianoa [View]
[Download]

Abstract: This paper addresses the stabilization and performance of the load frequency regulator. The problem is solved by using the theory of the optimal control. An algorithm, based on the new technique, proposed by the authors in [1], to overcome the difficulties of specifying the weighting matrices Q and R, is presented. The algorithm here proposed considers the multi-area electric energy system. The paper presents illustrative, numerical simulation results for this model. The results indicate that the obtained controller exhibits better performance then those based on classic control.

   Performance Evaluation of Electric Power Steering with IPM Motor and Drive System
By Hamidreza Akhondi, Jafar Milimonfared and Kaveh Malekian [View]
[Download]

Abstract: As the development of microprocessors, power electronic converters and electric motor drives, electric power steering system which uses an electric motor came to use a few year ago. Electric power steering systems have many advantages over traditional hydraulic power steering systems in engine efficiency, space efficiency, and environmental compatibility. This paper deals with design and optimization of an interior permanent magnet motor for power steering application. Direct search method is used for optimization. After optimization and finding motor parameters, an interior permanent magnet motor and drive with mechanical parts of electric power steering system are simulated and performance evaluation of system is done.

   Regulation Properties of Pumping Station Control System in the Highest Efficiency Range
By Szychta Leszek [View]
[Download]

Abstract: Three systems of control the work of watersupply pumping station were introduced in the article: the cascade, converter and highest efficiency range - worked out by the author. The motors of all pumps are supply by frequency converters in the system in the highest efficiency range. This makes possible the work of pumps in so called the recommended area in which the largest efficiencies step out. The author gives the conditions of the continuous and interrupted operation of the pump. The changes of the rotation speed were qualified stay in the function efficiency at the constant head for pumps characterized by specific speed nq=42. The author suggests applying the redimensioning pumps in the relation to the rated conditions of the demand.

   Robust Control Methodologies for Optical Micro Electro Mechanical System - New Approaches and Comparison
By Alireza Izadbakhsh [View]
[Download]

Abstract: The paper presents a comparison of three new robust control approaches for a micro electro mechanical system (MEMS) optical switch, considering uncertainties such as system parameter variations, external disturbance, and un-modeled dynamics. The control approaches are Sliding Mode Control, High Gain Control, and Model Free Based Control. Two of these approaches are quite novel in the field of MEMS control design. The comparative results highlights the main advantages of the proposed approaches which are simplicity, practicably, low computation burden, and low simulation time to control of electro mechanical systems.

   The Impact of Higher-Order Harmonics on Tripping of Residual Current Devices
By Stanislaw Czapp [View]
[Download]

Abstract: Distorted line to earth voltage on the output terminals of the inverter of variable speed drives results in an earth fault current comprising harmonics. Higher-order harmonics in the earth fault current have a negative effect on tripping of residual current devices. In some cases sensitivity of residual current devices rapidly decreases and protection against electric shock is not effective. In the paper results of the laboratory testing of residual current devices sensitivity are described.

EPE-PEMC 2008 - Topic: Related Topics
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2008 - Conference > EPE-PEMC 2008 - Topic: Related Topics
	[return to parent folder]

	Determination of the Characteristic Life Time of Paper-Insulated MV-Cables Based on a Partial Discharge and tan(δ) Diagnosis By I. Mladenovic	[View] [Download]
Abstract: Monitoring the condition of electrical equipment insulation by means of partial discharge measurement and analysis is an effective diagnostic tool for the prediction of service failures. In this paper an accelerated aging system specialized for paper insulated lead covered (PILC) cables, with a highly sensitive and selective PD-detection/localization and tan(δ) measurement is presented. It facilitates the monitoring of the entire aging process and the later development of sophisticated diagnostic criteria based on the physical aging process.

	DQ-Transformation Approach for Modelling and Stability Analysis of AC-DC Power System with Controlled PWM Rectifier and Constant Power Loads By K-N Areerak, S. V. Bozhko, G. M. Asher and D. W. P. Thomas	[View] [Download]
Abstract: In this paper a technique for analysing aircraft frequency wild power systems with constant power loads is developed and demonstrated. Power electronic based loads often behave as constant power loads, especially when feeding machine or actuator drives under current and speed control. The constant power (CP) loads can affect the stability of the power system. The problem is a particular issue in aircraft power systems as the proportion of CP loads increases with the advent of the more-electric aircraft. This paper deals with stability analysis of a three-phase frequency-wild AC power system with a CP load fed through a vector-controlled front-end PWM converter. The mathematical model suitable for stability analysis is derived using the DQ-transformation method. It is shown how the proposed approach can be applied to study the power system behaviour under different loads and parameters variations, as well as to assess the power system stability margins. The study is supported by intensive simulations that verify the reported theoretical results.

	Elimination of Increased Excitation of Common-Mode Oscillations in Electrical Drive Systems with Active Front End and Long Motor Cables By Thomas Weidinger	[View] [Download]
Abstract: In this paper the analysis of common-mode oscillations in electrical drive systems is presented. The analysed oscillations occur especially in electrical drive systems with active front end, common DC link and long motor cables. Because of resonant frequencies at 10 to 40 kHz low damping occurs. Some motors with concentrated winding show resonant behaviour in this frequency range and increase the overvoltages from the terminals to the star point. For example a torquemotor is analysed and modelled. In the concerned frequency range switching operations generate a significant excitation. As the focus of this paper a special coupling mechanism is described. This mechanism enforces the excitation by the switching of the active front end. Afterwards remedies are analysed. Simulations and measurements on sample systems with and without remedies show apparent voltage stressing of motors, common-mode losses and currents that disturb the drive system.

	Estimation of the Untapped Regenerative Braking Energy in Urban Electric Transportation Network By Leonards Latkovskis	[View] [Download]
Abstract: The paper presents an estimation of the reserves of untapped regenerative braking energy in the power supply network of urban electric transport. The estimation is made by a method based on probabilistic principles, transport timetable and measured power diagrams. The amount of unused regenerative energy is calculated for two substations in the electric transport network in Riga, with power measurement technique described for T3A tramcars. The results of the work allow calculation of economical aspects of the regenerative braking energy utilization not only for the current situation but also for future, taking into account growth in the transport fleet and changes in its organization.

	Genetic Identification of Parameters the Sandwich Piezoelectric Ceramic Transducers for Ultrasonic Systems By Pawel Fabijanski	[View] [Download]
Abstract: In this paper the genetic algorithm is used to optimization of parameters the equivalent electrical circuit of piezoelectric ceramic. Sandwich type piezoelectric ceramic transducer are the source of power ultrasounds when the vibration is activated by a voltage inverter. The output frequency of inverter most by equals the mechanical resonance frequency of the transducer and most by tuning with very high precise. In real circuits the mechanical resonant frequency is function of many parameters of piezoelectric material. The equivalent electrical circuit of transducer transforms this parameters in electrical value. This electrical circuit consist of connection in parallel: Co end RLC elements and this units are part of the oscillating circuit of inverter. The values of equivalent electrical circuit varies during the operation of transducer in function extending parameters, among others, the most important are temperature and time. In this situation to obtain the optimal value of the output voltage frequency of inverter most by know electrical parameters equivalent circuit of transducer. In the resolution of difficult problems to by effective the genetic algorithm.

	Implementation of a Virtual Laboratory for Low Power Electrical Drives By Gh. Baluta	[View] [Download]
Abstract: E-learning has introduced new opportunities in teaching and learning electrical engineering subjects. This paper presents the architecture of a virtual engineering laboratory, designed to allow remote training in the control of DC, brushless DC, and stepper servomotors. An example of DC servomotors control on virtual laboratory is also presented.

	Inner Gas Pressure Measurement Based Life-span Estimation of Electrolytic Capacitors By A. Riz	[View] [Download]
Abstract: As the wide scale usage of aluminum electrolytic capacitors it is very important to be familiar with them. The research and development of new and long sight better capacitors is very essential for circuit designers and costumers in general hence this is a very important issue to deal with. In the presented paper a summarize of the buildup and the useful life of the capacitors and a special procedure for the life-span analysis will be shown. The presentation is also deals with the related part of the Electrolytic Capacitor Measurement System (ECMS) implemented in the Aluminum Electrolytic Capacitor Development Laboratory of EPCOS Electronic Parts and COmponentS, Hungary. The results show, thanks to the introduction of the mentioned system, the efficiency of special measurements like the analysis of the useful life of aluminum electrolytic capacitors have been increased considerably.

	Internal Short Circuit in a Tooth Wound PMSM with Stranded Conductors By Damien Birolleau	[View] [Download]
Abstract: This paper deals with the modelization of an internal short circuit in a coil of a permanent magnet synchronous motor with a tooth wound stator. It focuses on the simulation of windings made of stranded conductors. The method of modelization is described, validated and applied to a case study. Different configurations of shortcircuits and their consequences are investigated.

	LCL-Load Modular Converter for Induction Heating By Maciej A. Dzieniakowski	[View] [Download]
Abstract: The paper presents novel resonant converter with LCL load, applied for induction heating. The control structure and power electronics circuit of VS inverter fed medium frequency induction furnace are described. The two resonant load topologies are investigated and applied. The control system assures fully synchronous operation in whole resonant load parameter changes. The control method and proposed converter topology results in resonant load independence on inverter parameters. It allows simple, modular converter construction. The present applications of the system cover range power to 1MW.

	On-Line PID Controller Tuning Using Genetic Algorithm and DSP PC Board By Pawel Fabijański	[View] [Download]
Abstract: In this paper we uses a software pack, which allows to adjust PID controller automatically in real time way in the case of changes parameters of used object. PID settings are optimized in real time by using genetic algorithm and are compared with generally accepted quality indicators for control systems like rise time, \% overshoot and settling time of step response or such coefficient like oscillations frequency, reduced damping and gain of second order object. A digital signal processor (DSP) is a specialized microprocessor designed specifically for digital signal processing generally in real time applications requiring high computation. The simulation results were verified by some laboratory test.

	Optimal Control: Load Frequency Control of a Large Power System By Sílvio José Pinto Simões Marianoa	[View] [Download]
Abstract: This paper addresses the stabilization and performance of the load frequency regulator. The problem is solved by using the theory of the optimal control. An algorithm, based on the new technique, proposed by the authors in [1], to overcome the difficulties of specifying the weighting matrices Q and R, is presented. The algorithm here proposed considers the multi-area electric energy system. The paper presents illustrative, numerical simulation results for this model. The results indicate that the obtained controller exhibits better performance then those based on classic control.

	Performance Evaluation of Electric Power Steering with IPM Motor and Drive System By Hamidreza Akhondi, Jafar Milimonfared and Kaveh Malekian	[View] [Download]
Abstract: As the development of microprocessors, power electronic converters and electric motor drives, electric power steering system which uses an electric motor came to use a few year ago. Electric power steering systems have many advantages over traditional hydraulic power steering systems in engine efficiency, space efficiency, and environmental compatibility. This paper deals with design and optimization of an interior permanent magnet motor for power steering application. Direct search method is used for optimization. After optimization and finding motor parameters, an interior permanent magnet motor and drive with mechanical parts of electric power steering system are simulated and performance evaluation of system is done.

	Regulation Properties of Pumping Station Control System in the Highest Efficiency Range By Szychta Leszek	[View] [Download]
Abstract: Three systems of control the work of watersupply pumping station were introduced in the article: the cascade, converter and highest efficiency range - worked out by the author. The motors of all pumps are supply by frequency converters in the system in the highest efficiency range. This makes possible the work of pumps in so called the recommended area in which the largest efficiencies step out. The author gives the conditions of the continuous and interrupted operation of the pump. The changes of the rotation speed were qualified stay in the function efficiency at the constant head for pumps characterized by specific speed nq=42. The author suggests applying the redimensioning pumps in the relation to the rated conditions of the demand.

	Robust Control Methodologies for Optical Micro Electro Mechanical System - New Approaches and Comparison By Alireza Izadbakhsh	[View] [Download]
Abstract: The paper presents a comparison of three new robust control approaches for a micro electro mechanical system (MEMS) optical switch, considering uncertainties such as system parameter variations, external disturbance, and un-modeled dynamics. The control approaches are Sliding Mode Control, High Gain Control, and Model Free Based Control. Two of these approaches are quite novel in the field of MEMS control design. The comparative results highlights the main advantages of the proposed approaches which are simplicity, practicably, low computation burden, and low simulation time to control of electro mechanical systems.

	The Impact of Higher-Order Harmonics on Tripping of Residual Current Devices By Stanislaw Czapp	[View] [Download]
Abstract: Distorted line to earth voltage on the output terminals of the inverter of variable speed drives results in an earth fault current comprising harmonics. Higher-order harmonics in the earth fault current have a negative effect on tripping of residual current devices. In some cases sensitivity of residual current devices rapidly decreases and protection against electric shock is not effective. In the paper results of the laboratory testing of residual current devices sensitivity are described.