EPE Association: EPE-PEMC 2008 - Topic: Power Electronics in Transportation

EPE-PEMC 2008 - Topic: Power Electronics in Transportation
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2008 - Conference > EPE-PEMC 2008 - Topic: Power Electronics in Transportation

   [return to parent folder]

   A Multi-Core PC-Based Simulator for the Hardware-In-the-Loop Testing of Modern Train and Ship Traction Systems
By Christian Dufour, Guillaume Dumur, Jean-Nicolas Paquin, Jean Bélanger [View]
[Download]

Abstract: Today, the development and integration of train and ship controllers is a more difficult task than ever. Emergence of high-power switching devices has enabled the development of new solutions with improved controllability and efficiency. It has also increased the necessity for more stringent test and integration capabilities since these new topologies come with less design experience on the part of the system designers. To address this issue, a real-time simulator can be a very useful tool to test, validate and integrate the various subsystems of modern rail vehicle devices. This paper presents such a real-time simulator, based on commercial-off-the-shelf PC technology, suitable for the simulation of train and ship propulsion devices. The requirements for rail/water vehicle test and integration reaches several levels on the control hierarchy from low-level power electronic converters used for propulsion and auxiliary systems to high-level supervisory controls. This paper places great emphasis on the real-time simulation of several high-power drives used for train and ship propulsion, including a multi-induction machine drive, a three-level GTO - PMSM drive and a high-power thyristor-based converter - synchronous machine drive. All models are designed first with the SimPowerSystems blockset and then automatically compiled and run on commercial PCs under RT-LAB. Interfaces to I/O are also made at the Simulink model level without any low-level coding required by the user. Supervisory control integration and testing can also be made using the RT-LAB real-time simulator. The other objective of this paper is to demonstrate that HIL testing of complex drives, such as the those found on trains, can be done using commercial-off-the-shelf (COTS) software and hardware and model-based design techniques that only require high-level system models suitable for system specifications down to controller test and final system integration.

   A New Novel Power Electronic Circuit to Reduce Stray Current and Rail Potential in DC Railway
By Reza Fotouhi [View]
[Download]

Abstract: The problem of stray current in DC railways has not been solved completely in spite of many years of research and investigation, specially where there is not good rail insulation to prevent corrosion risk to the infrastructure. A new novel circuit, based on power electronic semiconductors, which has the same advantage of a booster transformer in AC systems, is proposed in this paper for DC railways. This circuit forces the return current to flow through return current wire (RCW) instead of the rail or earth. As a result, the current of the contact wire (CW) and return current wire would be approximately the same. Then, not only has the stray current reduced but also the rail current and potential decreases as well.

   Analysis and Configuration of Supercapacitor Based Energy Storage System On-Board Light Rail Vehicles
By R. Barrero [View]
[Download]

Abstract: This article will propose different energy storage systems, ranging from 0.91 kWh to 1.56 kWh, suitable for a 30 m long tram. To configure the system regarding energy content, voltage variation, maximum current and power losses, a model of the tram, network and substations power flow has been developed in a Matlab/Simulink environment. Results obtained in energy savings at substation level vary from 24\% to 27,6\% under the same driving profile and auxiliaries load; while at the end-of-life of supercapacitors, the range varies from 18,1\% to 25,1\% depending on the super capacitor module used and vehicle load. The effect of the power converter between the energy storage system and the pantograph will be evaluated in terms of efficiency and rated power.

   Analysis of a H-NPC topology for an AC Traction Front-End Converter
By I. Etxeberria-Otadui, H. Gaztañaga, U. Viscarret and M. Caballero [View]
[Download]

Abstract: In this paper a H-NPC topology is analyzed as the front-end converter at an AC traction application. These converters permit to achieve higher voltage levels and better current quality spectra than conventional single-phase H-bridge converters. The objective here is to analyze the suitability of main modulation strategies for traction applications, and to study the design requirements of current and voltage control loops for this kind of applications. Presented control and modulation loops have been tested in simulation and have been verified experimentally in a prototype test bench, showing the appropriateness of the proposed converter topology and control structures.

   Characterization and Improved Control of a Brushless DC Drive with In-Wheel Motor
By Manuele Bertoluzzo [View]
[Download]

Abstract: The paper deals with a brushless DC drive belonging to the propulsion system of an innovative light electric vehicle. The drive consists of an in-wheel motor fed by a voltage-controlled inverter. At first, the parameters of the motor and the mechanical characteristics of the drive are measured; the latter results are supported by a formulation of the torque-speed equations. Afterwards, a novel strategy for the voltage control of the drive during the commutations is presented, intended to eliminate the torque ripple and the decrease in the available torque due to the commutations. Improvement in the drive performance achieved with the novel strategy is documented by simulation.

   Control of Primary Voltage Source Active Rectifiers for Traction Converter with Medium-Frequency Transformer
By Vojtĕch Blahník [View]
[Download]

Abstract: This paper deals with the new configuration of the traction converter with medium-frequency transformer intended for ac trolley wire fed locomotives. The main attention is paid to the primary serially connected single-phase voltage-source active rectifiers, which are directly connected to the trolley wire. This paper describes the control of the primary active rectifiers, presents simulation results as well as experimental evidence of designed lowvoltage laboratory prototype of loco converter of rated power of 12 kW.

   Control of Rotor Flux in AC Tram Drive During Sudden Braking Operation
By Andrzej Dębowski [View]
[Download]

Abstract: The paper focuses on the behavior of the rotor flux indirect control system for an inverter fed AC tram drive. The control strategy used in this drive is based on the original state stimulator concept and has been applied in several modernized trams and in a trolley-bus in Poland. In these vehicles some oscillations of the modulus of the rotor flux vector during sudden braking operation were observed. The phenomenon of oscillations was tested in laboratory stand with adequate physical model of real tram drive as well as in a computer simulation model. These research allowed to explain the nature of the oscillations and to find some way to improve the control quality.

   Design Considerations for Control of Traction Drive with Permanent Magnet Synchronous Machine
By Zdeněk Peroutka [View]
[Download]

Abstract: This contribution deals with the control of the wheel drive with permanent magnet synchronous machine of the tram car. In order to achieve minimal dimensions of PMSM and on the other hand to be able to provide sufficient torque, the drive is operating in very wide speed range in the field weakening and with the machine load angle of 90º. Thus, the new problem introduced by this drive is requirement for the limitation of the load angle. This paper presents proposed drive control, simulation results of tram drive prototype and experimental evidence of designed laboratory prototype of rated power of 10.7 kW.

   Design of High Power Electronic Building Block Based on Parallel of IGBTs for Electric Vehicle
By Wen Huiqing [View]
[Download]

Abstract: A number of IGBT modules or IGBT converters can be paralleled to enlarge output power level of the whole system, which is attractive in applications such as electrical vehicles, ships and spacecrafts where power density, power quality and cost are very sensitive. Firstly, this paper explains the reason why the NPT IGBT is fit for parallel operation. The principle of IGBT parallel operation and the new evaluation plan are also presented. A power electronic building block (PEBB) based on parallel of IGBT is designed and a Saber-based accurate simulation platform including IGBT model and main parasitic has been developed. The detailed experimental results are present and compared with the simulation results, which show the PEBB module is practical and the new evaluation is valid.

   Dual-Source Fed Multiphase Traction System with Standard and Non-Standard Control Regimes Based on Synchronized PWM
By Valentin Oleschuk [View]
[Download]

Abstract: This paper presents results of application of algorithms of synchronized pulsewidth modulation (PWM) for control of hybrid electric vehicle drive supplied by dual thee-phase inverter system with two DC sources. Both standard linear V/F=const and non-standard non-linear control regimes of hybrid vehicle drive with synchronized PWM have been analyzed and compared. Simulation results are given for the system with basic continuous and discontinuous schemes of synchronized PWM. The spectra of the phase voltages of hybrid electric vehicle with synchronized PWM do not contain even harmonics and sub-harmonics in both standard and non-standard modes, which is especially important for the high power/current applications.

   Energy Management Strategy for Coupling Supercapacitors and Batteries with DC-DC Converters for Hybrid Vehicle Applications
By M. B. Camara, F. Gustin, H. Gualous and A. Berthon [View]
[Download]

Abstract: In this paper, the authors propose an approach to the problem of the energy management in ECCE laboratory hybrid vehicle project. ECCE is a series hybrid vehicle, which currently has three sources of energy: two diesel motors each coupled with an alternator and a battery module of rated voltage DC 540 V. This contribution is focused on the energy coupling between batteries and two supercapacitors modules. The authors present a strategy for coupling these power sources with the batteries in order to find the best compromise between sizes of the on-board devices, dynamics of the supply and efficiency of the energy storage. The target is to provide 200 kW power during 20s from the supercapacitors modules.

   Energy Saving Control of Tram Motors Taking Light Signalling and City Disturbances into Account
By Stanislaw Rawicki [View]
[Download]

Abstract: The paper deals with the problems of the tram vehicle control according to the criterion of the minimum electrical energy use. The author has extended the methodics given in literature and has elaborated the algorithm of the energy saving tram traffic allowing for the light signalling and ride perturbations. During the running in the city, tram ride parameters change frequently. Mathematical optimization methods make possible the determination of the control means for the tram run with the minimum energy consumption. The influence of the following traffic disturbances was described: the light signalling, different speed limitations, stays, changes of size of the electrical energy recuperation during the braking and variations of the traction network voltage.

   Hybrid - Type System of Power Supply for a Trolleybus with an Asynchronous Motor
By Zygmunt Giziński, Marcin Gąsiewski, Ireneusz Maścibrodzki, Micha Zych, Krzysztof Zymmer and Marcin Żulawnik, [View]
[Download]

Abstract: The paper presents results of research work on a prototype trolleybus with asynchronous motor drive system and with energy storage operated by the Urban Transportation Company in Lublin. There are shown operation test results with a capacitor type energy storage and with an additional accumulator battery and without the battery. Basing on the operation test results, the advantages are shown, resulting from the introduction of this technical solution, such as energy saving and the possibilities of travelling over sections of routes without power supply from the traction network.

   Improvement of the Energy Recovery of Traction Electrical Drives Using Supercapacitors
By Diego Iannuzzi [View]
[Download]

Abstract: In the paper the possibility of improving the energy recovered during the braking of railway vehicles and reduction of power peaks during accelerating are discussed. The energy available from the regenerative braking of the motor is stored into supercapacitor sets placed on board and reused subsequently for the acceleration of the train. This auxiliary storage system allows the reduction of the losses on the line, because the power peaks are shaved by supercapacitors and, hence, the rms power supplied is reduced. In addition, also the energy consumption of the train can be reduced respect to traditional convoys, especially if the characteristic duty-cycle presents many accelerations and braking periods as the case of subways trains. The set of supercapacitors needs the use of an intermediate dc/dc converter in order to harmonize the voltage with that of the dc-link of the drive and control the power flows of the supercapacitors. The mathematical model of the whole system and the control strategy of energy management are presented.The actual possibilities of the energy recovery are shown by means of numeric simulations and expressed in percentage respect to the energy drawn during accelerations. The control strategy has been experimentally validated on a scale system made of an asynchronous drive supplied by a dc source and a set of supercapacitors as auxiliary storage device.

   Practical Aspects on the Improved DC Driving System Used in Electric Urban Traction
By Petre-Marian Nicolae [View]
[Download]

Abstract: The paper presents some practical considerations and experimental results obtained by the exploitation of a tram that has an electric driving system with an improved technological solution. One presents the technological solution using chopper that substitutes the initial accelerators of the tram. Some aspects concerning the operation in running and respectively in braking regimes in the new configuration (including the regenerative braking regime) are discussed. Some considerations with respect to the electromagnetic compatibility problems and modalities to improve it are made. The recordings of the current and voltage waveforms, during the normal running stage, when the tram climbs a ramp and respectively goes down on a slope are presented and explained. The experimental determinations revealed that the system was designed correctly, in order to support all the operational conditions that could appear in its exploitation.

   Sliding-Mode Approach to Control Design for Induction Motor Drive Fed by a Three-Level Voltage-Source Inverter
By Sergey Ryvkin [View]
[Download]

Abstract: A novel sliding mode control for the induction motor (IM) fed by three-level voltage-source inverter (3LVSI) is proposed in this paper. The "classical" results of sliding-mode theory were extended on the actual variable structure system with more then 2m variable structures (m is the control space order) by using an original two-step design procedure that allows separately to use the nonlinearity of the IM and the switching character of the 3LVSI. The based on this design procedure original control algorithm that includes a choice condition for 3L-VSI input dc link voltage and a switch table for the 3L-VSI semiconductor switches is designed. The main advantages of such approach are given as follows: the control design is simpler and more graphical; the control system has such advantageous characteristics of the control plant with sliding mode control as high dynamic, low sensitivity to disturbance of both the load and the to plant parameter variations; the requirements to the quality of the input dc-link voltage and as a result to the dc-line filter capacitor are reduced; the measurement precision of the stator flux position is within (π/6). Simulation results are presented to validate the theoretical analysis and demonstrate the performance of the proposed control.

   Slip Control Upgrades for Light-Rail Electric Traction Drives
By Madis Lehtla and Hardi Hõimoja [View]
[Download]

Abstract: Many obsolete drives such as a rheostat, contactor or camshaft-contact controlled DC motor drives have often poor dynamic properties in insufficient adhesion conditions. Light-rail vehicles running in many cities already have switched-mode traction drives with thyristorbased or IGBT-based converters that often lack high quality slip, antilock or creep control. Switched-mode converter based multi-motor drives could be partially upgraded to microcontroller-based control. This paper presents and analyses some approaches to be used for performance, efficiency and safety improvement.

   Stability Analysis on the DC Power Distribution System of More Electric Aircraft
By H. Zhang [View]
[Download]

Abstract: The local DC Power Distribution System (PDS) of a More Electric Aircraft is one of the cores of the electric power transmission. Generally, the PDS is made up of small power subsystems designed on their own stand-alone operation. But the interaction between the subsystems (sources and loads) induces some problems of stability. This paper compares the different stability behaviours of two load models: resistive load and constant power load. Some tests for the two load models at different operating points are carried out and the results are compared. The small signal theory and the impedance criterion GMPM (Gain Margin Phase Margin) are used to analyse the stability of each system. At conclusion, some statements are expressed to contribute to such electric interconnected systems stability.

   Supply of Electric Vehicles via Magnetically Coupled Air Coils
By Slawomir Judek [View]
[Download]

Abstract: The paper describes the contactless electrical energy transfer system (CEETS), by which electrical energy may be transmitted, without electrical connection or physical contact, through the large air gap. In this case energy is transmitted via coreless transformer. Coupling between the coils changes and depend on dimension of air gap. The efficiency of CEETS is mainly depended on the transmission frequency. Additionally large leakage inductances may be compensated also in resonance condition by adding capacitors to the coils. The article presents theoretical analyses and simulation results of transformer equivalent circuit with capacitors. Theoretical developments are compared with practical measurements from a prototype contactless system.

   The Study of Using the Traction Drive Topology with the Middle-Frequency Transformer
By Martin Pittermann [View]
[Download]

Abstract: This paper presents research motivated by industrial demand for special traction drive topology devoted to minimization of traction transformer weight of traction vehicles. The main attention has been given to the special traction drive topology for AC power systems: input high voltage trolley converter (single phase) - middle frequency transformer (single phase) - output converter (single phase voltage-source active rectifier + three phase voltage-source inverter) - traction motor. This configuration can minimize traction transformer weight against topology with classical 50 Hz traction transformer. Several variants of innovative topologies of the traction vehicles fulfill the weight reduce requirements have been presented.

EPE-PEMC 2008 - Topic: Power Electronics in Transportation
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2008 - Conference > EPE-PEMC 2008 - Topic: Power Electronics in Transportation
	[return to parent folder]

	A Multi-Core PC-Based Simulator for the Hardware-In-the-Loop Testing of Modern Train and Ship Traction Systems By Christian Dufour, Guillaume Dumur, Jean-Nicolas Paquin, Jean Bélanger	[View] [Download]
Abstract: Today, the development and integration of train and ship controllers is a more difficult task than ever. Emergence of high-power switching devices has enabled the development of new solutions with improved controllability and efficiency. It has also increased the necessity for more stringent test and integration capabilities since these new topologies come with less design experience on the part of the system designers. To address this issue, a real-time simulator can be a very useful tool to test, validate and integrate the various subsystems of modern rail vehicle devices. This paper presents such a real-time simulator, based on commercial-off-the-shelf PC technology, suitable for the simulation of train and ship propulsion devices. The requirements for rail/water vehicle test and integration reaches several levels on the control hierarchy from low-level power electronic converters used for propulsion and auxiliary systems to high-level supervisory controls. This paper places great emphasis on the real-time simulation of several high-power drives used for train and ship propulsion, including a multi-induction machine drive, a three-level GTO - PMSM drive and a high-power thyristor-based converter - synchronous machine drive. All models are designed first with the SimPowerSystems blockset and then automatically compiled and run on commercial PCs under RT-LAB. Interfaces to I/O are also made at the Simulink model level without any low-level coding required by the user. Supervisory control integration and testing can also be made using the RT-LAB real-time simulator. The other objective of this paper is to demonstrate that HIL testing of complex drives, such as the those found on trains, can be done using commercial-off-the-shelf (COTS) software and hardware and model-based design techniques that only require high-level system models suitable for system specifications down to controller test and final system integration.

	A New Novel Power Electronic Circuit to Reduce Stray Current and Rail Potential in DC Railway By Reza Fotouhi	[View] [Download]
Abstract: The problem of stray current in DC railways has not been solved completely in spite of many years of research and investigation, specially where there is not good rail insulation to prevent corrosion risk to the infrastructure. A new novel circuit, based on power electronic semiconductors, which has the same advantage of a booster transformer in AC systems, is proposed in this paper for DC railways. This circuit forces the return current to flow through return current wire (RCW) instead of the rail or earth. As a result, the current of the contact wire (CW) and return current wire would be approximately the same. Then, not only has the stray current reduced but also the rail current and potential decreases as well.

	Analysis and Configuration of Supercapacitor Based Energy Storage System On-Board Light Rail Vehicles By R. Barrero	[View] [Download]
Abstract: This article will propose different energy storage systems, ranging from 0.91 kWh to 1.56 kWh, suitable for a 30 m long tram. To configure the system regarding energy content, voltage variation, maximum current and power losses, a model of the tram, network and substations power flow has been developed in a Matlab/Simulink environment. Results obtained in energy savings at substation level vary from 24\% to 27,6\% under the same driving profile and auxiliaries load; while at the end-of-life of supercapacitors, the range varies from 18,1\% to 25,1\% depending on the super capacitor module used and vehicle load. The effect of the power converter between the energy storage system and the pantograph will be evaluated in terms of efficiency and rated power.

	Analysis of a H-NPC topology for an AC Traction Front-End Converter By I. Etxeberria-Otadui, H. Gaztañaga, U. Viscarret and M. Caballero	[View] [Download]
Abstract: In this paper a H-NPC topology is analyzed as the front-end converter at an AC traction application. These converters permit to achieve higher voltage levels and better current quality spectra than conventional single-phase H-bridge converters. The objective here is to analyze the suitability of main modulation strategies for traction applications, and to study the design requirements of current and voltage control loops for this kind of applications. Presented control and modulation loops have been tested in simulation and have been verified experimentally in a prototype test bench, showing the appropriateness of the proposed converter topology and control structures.

	Characterization and Improved Control of a Brushless DC Drive with In-Wheel Motor By Manuele Bertoluzzo	[View] [Download]
Abstract: The paper deals with a brushless DC drive belonging to the propulsion system of an innovative light electric vehicle. The drive consists of an in-wheel motor fed by a voltage-controlled inverter. At first, the parameters of the motor and the mechanical characteristics of the drive are measured; the latter results are supported by a formulation of the torque-speed equations. Afterwards, a novel strategy for the voltage control of the drive during the commutations is presented, intended to eliminate the torque ripple and the decrease in the available torque due to the commutations. Improvement in the drive performance achieved with the novel strategy is documented by simulation.

	Control of Primary Voltage Source Active Rectifiers for Traction Converter with Medium-Frequency Transformer By Vojtĕch Blahník	[View] [Download]
Abstract: This paper deals with the new configuration of the traction converter with medium-frequency transformer intended for ac trolley wire fed locomotives. The main attention is paid to the primary serially connected single-phase voltage-source active rectifiers, which are directly connected to the trolley wire. This paper describes the control of the primary active rectifiers, presents simulation results as well as experimental evidence of designed lowvoltage laboratory prototype of loco converter of rated power of 12 kW.

	Control of Rotor Flux in AC Tram Drive During Sudden Braking Operation By Andrzej Dębowski	[View] [Download]
Abstract: The paper focuses on the behavior of the rotor flux indirect control system for an inverter fed AC tram drive. The control strategy used in this drive is based on the original state stimulator concept and has been applied in several modernized trams and in a trolley-bus in Poland. In these vehicles some oscillations of the modulus of the rotor flux vector during sudden braking operation were observed. The phenomenon of oscillations was tested in laboratory stand with adequate physical model of real tram drive as well as in a computer simulation model. These research allowed to explain the nature of the oscillations and to find some way to improve the control quality.

	Design Considerations for Control of Traction Drive with Permanent Magnet Synchronous Machine By Zdeněk Peroutka	[View] [Download]
Abstract: This contribution deals with the control of the wheel drive with permanent magnet synchronous machine of the tram car. In order to achieve minimal dimensions of PMSM and on the other hand to be able to provide sufficient torque, the drive is operating in very wide speed range in the field weakening and with the machine load angle of 90º. Thus, the new problem introduced by this drive is requirement for the limitation of the load angle. This paper presents proposed drive control, simulation results of tram drive prototype and experimental evidence of designed laboratory prototype of rated power of 10.7 kW.

	Design of High Power Electronic Building Block Based on Parallel of IGBTs for Electric Vehicle By Wen Huiqing	[View] [Download]
Abstract: A number of IGBT modules or IGBT converters can be paralleled to enlarge output power level of the whole system, which is attractive in applications such as electrical vehicles, ships and spacecrafts where power density, power quality and cost are very sensitive. Firstly, this paper explains the reason why the NPT IGBT is fit for parallel operation. The principle of IGBT parallel operation and the new evaluation plan are also presented. A power electronic building block (PEBB) based on parallel of IGBT is designed and a Saber-based accurate simulation platform including IGBT model and main parasitic has been developed. The detailed experimental results are present and compared with the simulation results, which show the PEBB module is practical and the new evaluation is valid.

	Dual-Source Fed Multiphase Traction System with Standard and Non-Standard Control Regimes Based on Synchronized PWM By Valentin Oleschuk	[View] [Download]
Abstract: This paper presents results of application of algorithms of synchronized pulsewidth modulation (PWM) for control of hybrid electric vehicle drive supplied by dual thee-phase inverter system with two DC sources. Both standard linear V/F=const and non-standard non-linear control regimes of hybrid vehicle drive with synchronized PWM have been analyzed and compared. Simulation results are given for the system with basic continuous and discontinuous schemes of synchronized PWM. The spectra of the phase voltages of hybrid electric vehicle with synchronized PWM do not contain even harmonics and sub-harmonics in both standard and non-standard modes, which is especially important for the high power/current applications.

	Energy Management Strategy for Coupling Supercapacitors and Batteries with DC-DC Converters for Hybrid Vehicle Applications By M. B. Camara, F. Gustin, H. Gualous and A. Berthon	[View] [Download]
Abstract: In this paper, the authors propose an approach to the problem of the energy management in ECCE laboratory hybrid vehicle project. ECCE is a series hybrid vehicle, which currently has three sources of energy: two diesel motors each coupled with an alternator and a battery module of rated voltage DC 540 V. This contribution is focused on the energy coupling between batteries and two supercapacitors modules. The authors present a strategy for coupling these power sources with the batteries in order to find the best compromise between sizes of the on-board devices, dynamics of the supply and efficiency of the energy storage. The target is to provide 200 kW power during 20s from the supercapacitors modules.

	Energy Saving Control of Tram Motors Taking Light Signalling and City Disturbances into Account By Stanislaw Rawicki	[View] [Download]
Abstract: The paper deals with the problems of the tram vehicle control according to the criterion of the minimum electrical energy use. The author has extended the methodics given in literature and has elaborated the algorithm of the energy saving tram traffic allowing for the light signalling and ride perturbations. During the running in the city, tram ride parameters change frequently. Mathematical optimization methods make possible the determination of the control means for the tram run with the minimum energy consumption. The influence of the following traffic disturbances was described: the light signalling, different speed limitations, stays, changes of size of the electrical energy recuperation during the braking and variations of the traction network voltage.

	Hybrid - Type System of Power Supply for a Trolleybus with an Asynchronous Motor By Zygmunt Giziński, Marcin Gąsiewski, Ireneusz Maścibrodzki, Micha Zych, Krzysztof Zymmer and Marcin Żulawnik,	[View] [Download]
Abstract: The paper presents results of research work on a prototype trolleybus with asynchronous motor drive system and with energy storage operated by the Urban Transportation Company in Lublin. There are shown operation test results with a capacitor type energy storage and with an additional accumulator battery and without the battery. Basing on the operation test results, the advantages are shown, resulting from the introduction of this technical solution, such as energy saving and the possibilities of travelling over sections of routes without power supply from the traction network.

	Improvement of the Energy Recovery of Traction Electrical Drives Using Supercapacitors By Diego Iannuzzi	[View] [Download]
Abstract: In the paper the possibility of improving the energy recovered during the braking of railway vehicles and reduction of power peaks during accelerating are discussed. The energy available from the regenerative braking of the motor is stored into supercapacitor sets placed on board and reused subsequently for the acceleration of the train. This auxiliary storage system allows the reduction of the losses on the line, because the power peaks are shaved by supercapacitors and, hence, the rms power supplied is reduced. In addition, also the energy consumption of the train can be reduced respect to traditional convoys, especially if the characteristic duty-cycle presents many accelerations and braking periods as the case of subways trains. The set of supercapacitors needs the use of an intermediate dc/dc converter in order to harmonize the voltage with that of the dc-link of the drive and control the power flows of the supercapacitors. The mathematical model of the whole system and the control strategy of energy management are presented.The actual possibilities of the energy recovery are shown by means of numeric simulations and expressed in percentage respect to the energy drawn during accelerations. The control strategy has been experimentally validated on a scale system made of an asynchronous drive supplied by a dc source and a set of supercapacitors as auxiliary storage device.

	Practical Aspects on the Improved DC Driving System Used in Electric Urban Traction By Petre-Marian Nicolae	[View] [Download]
Abstract: The paper presents some practical considerations and experimental results obtained by the exploitation of a tram that has an electric driving system with an improved technological solution. One presents the technological solution using chopper that substitutes the initial accelerators of the tram. Some aspects concerning the operation in running and respectively in braking regimes in the new configuration (including the regenerative braking regime) are discussed. Some considerations with respect to the electromagnetic compatibility problems and modalities to improve it are made. The recordings of the current and voltage waveforms, during the normal running stage, when the tram climbs a ramp and respectively goes down on a slope are presented and explained. The experimental determinations revealed that the system was designed correctly, in order to support all the operational conditions that could appear in its exploitation.

	Sliding-Mode Approach to Control Design for Induction Motor Drive Fed by a Three-Level Voltage-Source Inverter By Sergey Ryvkin	[View] [Download]
Abstract: A novel sliding mode control for the induction motor (IM) fed by three-level voltage-source inverter (3LVSI) is proposed in this paper. The "classical" results of sliding-mode theory were extended on the actual variable structure system with more then 2m variable structures (m is the control space order) by using an original two-step design procedure that allows separately to use the nonlinearity of the IM and the switching character of the 3LVSI. The based on this design procedure original control algorithm that includes a choice condition for 3L-VSI input dc link voltage and a switch table for the 3L-VSI semiconductor switches is designed. The main advantages of such approach are given as follows: the control design is simpler and more graphical; the control system has such advantageous characteristics of the control plant with sliding mode control as high dynamic, low sensitivity to disturbance of both the load and the to plant parameter variations; the requirements to the quality of the input dc-link voltage and as a result to the dc-line filter capacitor are reduced; the measurement precision of the stator flux position is within (π/6). Simulation results are presented to validate the theoretical analysis and demonstrate the performance of the proposed control.

	Slip Control Upgrades for Light-Rail Electric Traction Drives By Madis Lehtla and Hardi Hõimoja	[View] [Download]
Abstract: Many obsolete drives such as a rheostat, contactor or camshaft-contact controlled DC motor drives have often poor dynamic properties in insufficient adhesion conditions. Light-rail vehicles running in many cities already have switched-mode traction drives with thyristorbased or IGBT-based converters that often lack high quality slip, antilock or creep control. Switched-mode converter based multi-motor drives could be partially upgraded to microcontroller-based control. This paper presents and analyses some approaches to be used for performance, efficiency and safety improvement.

	Stability Analysis on the DC Power Distribution System of More Electric Aircraft By H. Zhang	[View] [Download]
Abstract: The local DC Power Distribution System (PDS) of a More Electric Aircraft is one of the cores of the electric power transmission. Generally, the PDS is made up of small power subsystems designed on their own stand-alone operation. But the interaction between the subsystems (sources and loads) induces some problems of stability. This paper compares the different stability behaviours of two load models: resistive load and constant power load. Some tests for the two load models at different operating points are carried out and the results are compared. The small signal theory and the impedance criterion GMPM (Gain Margin Phase Margin) are used to analyse the stability of each system. At conclusion, some statements are expressed to contribute to such electric interconnected systems stability.

	Supply of Electric Vehicles via Magnetically Coupled Air Coils By Slawomir Judek	[View] [Download]
Abstract: The paper describes the contactless electrical energy transfer system (CEETS), by which electrical energy may be transmitted, without electrical connection or physical contact, through the large air gap. In this case energy is transmitted via coreless transformer. Coupling between the coils changes and depend on dimension of air gap. The efficiency of CEETS is mainly depended on the transmission frequency. Additionally large leakage inductances may be compensated also in resonance condition by adding capacitors to the coils. The article presents theoretical analyses and simulation results of transformer equivalent circuit with capacitors. Theoretical developments are compared with practical measurements from a prototype contactless system.

	The Study of Using the Traction Drive Topology with the Middle-Frequency Transformer By Martin Pittermann	[View] [Download]
Abstract: This paper presents research motivated by industrial demand for special traction drive topology devoted to minimization of traction transformer weight of traction vehicles. The main attention has been given to the special traction drive topology for AC power systems: input high voltage trolley converter (single phase) - middle frequency transformer (single phase) - output converter (single phase voltage-source active rectifier + three phase voltage-source inverter) - traction motor. This configuration can minimize traction transformer weight against topology with classical 50 Hz traction transformer. Several variants of innovative topologies of the traction vehicles fulfill the weight reduce requirements have been presented.