EPE Association: EPE 1997 – 87: Dialogue Session DS7b: BATTERY CHARGER, BATTERY MANAGEMENT, TEST BENCH

EPE 1997 – 87: Dialogue Session DS7b: BATTERY CHARGER, BATTERY MANAGEMENT, TEST BENCH
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1997 - Conference > EPE 1997 – 87: Dialogue Session DS7b: BATTERY CHARGER, BATTERY MANAGEMENT, TEST BENCH

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   BATTERY MANAGEMENT SYSTEM WITH A TWO WIRE BUS: REALIZATION AND PRACTICAL EXPERIENCES
By Bernhard Hauck; Hans Kahlen [View]
[Download]

Abstract: Batteries have a strong stress during their lifetime. For extension, battery management systems should be used. With these systems a monitoring and charge equalization should be possible. The system with the two wire bus uses the same physical bussystem for communication and for charge equalization. The charge equalization is done in time division-multiplex with the communication. The used protocol for the communication is a masterslave protocol. Further the master can switch between communication and charge equalization. The slaves operate with a measurement system with high accuracy for the voltage measurement of the respective part battery. They are connected to the bussystem using a high frequency transformer. The patent for this system is pending.

   BATTERY TESTING WITH A CURRENT CONTROLLED HIGH LOAD RESISTOR
By Hans Kahlen [View]
[Download]

Abstract: Batteries are normally tested on a battery test bench. There are different goals like cycling to monitor the life time or to measure the capacity at different temperatures. For batteries in electric vehicles, fork-lift trucks or other mobile use a capacity check is necessary from time to time. To test electric vehicle batteries everywhere a special high load resistor with current control was developed. The light and small device is designed for adjustable currents of 0-75A, battery voltages of l00V- 350V and a maximum power of 15kW.

   EFFICIENCY OF OFF-BOARD, HIGH POWER, ELECTRIC VEHICLE BATTERY CHARGERS WITH ACTIVE POWER LINE CONDITIONING CAPABILITIES
By P. Karlsson; M. Bojrup; M. Alaküla; L.Gertmar [View]
[Download]

Abstract: A comparison is made of battery charger topologies for electric vehicles. The chargers are all off-board, and capable of active power line conditioning and bi-directional power flow to compensate local utilities during peak power loads. The active power line conditioning capability is important, since an increase of battery chargers based on ordinary diode rectifiers would increase the low order harmonic content in grid currents. The battery chargers studied are one hard switched with a voltage-stiff de link, and three soft switched with quasi-resonant de links. Performance characteristics and energy conversion efficiency were evaluated from simulations. Indeed, the results imply that quasi resonant topologies have higher efficiency than hard switched. The drawback with the soft switched de links studied is the additional components, active and passive, needed for quasi-resonant operation. In battery charger applications, where high power efficiency is of prime interest, quasi-resonant topologies should be chosen.

   CONTACTLESS POWER TRANSMISSION: FREQUENCY TUNING BY A MAXIMUM POWER TRACKING METHOD
By P. Germano; M. Jufer [View]
[Download]

Abstract: A new type of electric vehicle has been developed. It is based on an induction energy transfer, realised by an ironless transformer, at high frequency (5 to 100 kHz). The working frequency depends on the position of the vehicle, relative to the primaries and on the load. This is a consequence of the variation of the coupling between the primaries and the secondary relative to the position. This effect is increased with the load. The aim is to tune the frequency by measuring and maximising the power transmitted to the secondary. The way of tracking the maximum power consists in applying a frequency variation to the system and measuring the corresponding power variation. Therefore the optimal frequency is reached. Practical results are shown.

   AN ORIGINAL STATE OF CHARGE GAUGE FOR NICKEL- CADMIUM TRACTION BATTERIES ASSOCIATING A COULOMETRIC MEASUREMENT WITH IMPEDANCEMETRY
By E. Rullière; S. Nugues; E. Toutain [View]
[Download]

Abstract: A coulometric measurement of available energy in a traction battery is not accurate enough because of the influence of current, temperature, ageing, self-discharge, ... This is why we present a method including a classical Ampere-hours measurement and an impedance measurement at given frequencies; an experimental bench had to be realized in order to measure the impedance of batteries at differents frequencies and differents states of charge (SOC). Also, an analysis of the results had to be done in order to choose a good measurement strategy (i.e. deduce the SOC with a good accuracy and a minimum of experiments).

   CHARGE EQUALIZATION USING A NON-DISSIPATIVE CURRENT DIVERTER WITH A CENTRALIZED MULTIWINDING TRANSFORMER
By Nasser H. Kutkut [View]
[Download]

Abstract: This paper presents a new technique for equalizing series connected battery stacks using a non-dissipative current diverter. Non dissipative current diverters provide a means to divert the charging current away from a fully charged cell to weak cells in the stack in a lossless manner. This allows the rest of the stack to be fully charged while avoiding overcharging healthy cells. The proposed technique utilizes a centralized multiwinding transformer to divert the charging current away from overcharged cells.

   A THREE-PHASE ZERO-VOLTAGE-TRANSITION INVERTER WITH INDUCTOR FEEDBACK
By S.C. Frame; D. Katsis; D. H. Lee; D. Boroyevich; F. C. Lee [View]
[Download]

Abstract: A novel zero-voltage transition (ZVT) three~phase voltage source inverter is proposed and experimentally verified. This topology uses a low-power auxiliary circuit employing inductor feedback. The auxiliary circuit activates for a short period prior to main switch turn-on to achieve ZVT. An advantage of this inductor feedback topology is that the auxiliary devices accomplish ZVT without any modification of the original switch modulation scheme. The proposed soft-switching inverter offers reduced device stress and increased efficiency compared to conventional hard-switched inverters.

   DEVELOPMENT OF A BRUSHLESS DC DRIVE FOR ELECTRIC VEHICLES
By P. Van Tichelen; D. Blight; P. Coenen; F. Vermeulen [View]
[Download]

Abstract: This paper describes the development of a high speed (12000 rpm) 44 kW Brushless DC motor, transmission and controller for an electric vehicle with field weakening. Drive train performance, vehicle integration requirements, design trade off and controller functions will be discussed.

EPE 1997 – 87: Dialogue Session DS7b: BATTERY CHARGER, BATTERY MANAGEMENT, TEST BENCH
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1997 - Conference > EPE 1997 – 87: Dialogue Session DS7b: BATTERY CHARGER, BATTERY MANAGEMENT, TEST BENCH
	[return to parent folder]

	BATTERY MANAGEMENT SYSTEM WITH A TWO WIRE BUS: REALIZATION AND PRACTICAL EXPERIENCES By Bernhard Hauck; Hans Kahlen	[View] [Download]
Abstract: Batteries have a strong stress during their lifetime. For extension, battery management systems should be used. With these systems a monitoring and charge equalization should be possible. The system with the two wire bus uses the same physical bussystem for communication and for charge equalization. The charge equalization is done in time division-multiplex with the communication. The used protocol for the communication is a masterslave protocol. Further the master can switch between communication and charge equalization. The slaves operate with a measurement system with high accuracy for the voltage measurement of the respective part battery. They are connected to the bussystem using a high frequency transformer. The patent for this system is pending.

	BATTERY TESTING WITH A CURRENT CONTROLLED HIGH LOAD RESISTOR By Hans Kahlen	[View] [Download]
Abstract: Batteries are normally tested on a battery test bench. There are different goals like cycling to monitor the life time or to measure the capacity at different temperatures. For batteries in electric vehicles, fork-lift trucks or other mobile use a capacity check is necessary from time to time. To test electric vehicle batteries everywhere a special high load resistor with current control was developed. The light and small device is designed for adjustable currents of 0-75A, battery voltages of l00V- 350V and a maximum power of 15kW.

	EFFICIENCY OF OFF-BOARD, HIGH POWER, ELECTRIC VEHICLE BATTERY CHARGERS WITH ACTIVE POWER LINE CONDITIONING CAPABILITIES By P. Karlsson; M. Bojrup; M. Alaküla; L.Gertmar	[View] [Download]
Abstract: A comparison is made of battery charger topologies for electric vehicles. The chargers are all off-board, and capable of active power line conditioning and bi-directional power flow to compensate local utilities during peak power loads. The active power line conditioning capability is important, since an increase of battery chargers based on ordinary diode rectifiers would increase the low order harmonic content in grid currents. The battery chargers studied are one hard switched with a voltage-stiff de link, and three soft switched with quasi-resonant de links. Performance characteristics and energy conversion efficiency were evaluated from simulations. Indeed, the results imply that quasi resonant topologies have higher efficiency than hard switched. The drawback with the soft switched de links studied is the additional components, active and passive, needed for quasi-resonant operation. In battery charger applications, where high power efficiency is of prime interest, quasi-resonant topologies should be chosen.

	CONTACTLESS POWER TRANSMISSION: FREQUENCY TUNING BY A MAXIMUM POWER TRACKING METHOD By P. Germano; M. Jufer	[View] [Download]
Abstract: A new type of electric vehicle has been developed. It is based on an induction energy transfer, realised by an ironless transformer, at high frequency (5 to 100 kHz). The working frequency depends on the position of the vehicle, relative to the primaries and on the load. This is a consequence of the variation of the coupling between the primaries and the secondary relative to the position. This effect is increased with the load. The aim is to tune the frequency by measuring and maximising the power transmitted to the secondary. The way of tracking the maximum power consists in applying a frequency variation to the system and measuring the corresponding power variation. Therefore the optimal frequency is reached. Practical results are shown.

	AN ORIGINAL STATE OF CHARGE GAUGE FOR NICKEL- CADMIUM TRACTION BATTERIES ASSOCIATING A COULOMETRIC MEASUREMENT WITH IMPEDANCEMETRY By E. Rullière; S. Nugues; E. Toutain	[View] [Download]
Abstract: A coulometric measurement of available energy in a traction battery is not accurate enough because of the influence of current, temperature, ageing, self-discharge, ... This is why we present a method including a classical Ampere-hours measurement and an impedance measurement at given frequencies; an experimental bench had to be realized in order to measure the impedance of batteries at differents frequencies and differents states of charge (SOC). Also, an analysis of the results had to be done in order to choose a good measurement strategy (i.e. deduce the SOC with a good accuracy and a minimum of experiments).

	CHARGE EQUALIZATION USING A NON-DISSIPATIVE CURRENT DIVERTER WITH A CENTRALIZED MULTIWINDING TRANSFORMER By Nasser H. Kutkut	[View] [Download]
Abstract: This paper presents a new technique for equalizing series connected battery stacks using a non-dissipative current diverter. Non dissipative current diverters provide a means to divert the charging current away from a fully charged cell to weak cells in the stack in a lossless manner. This allows the rest of the stack to be fully charged while avoiding overcharging healthy cells. The proposed technique utilizes a centralized multiwinding transformer to divert the charging current away from overcharged cells.

	A THREE-PHASE ZERO-VOLTAGE-TRANSITION INVERTER WITH INDUCTOR FEEDBACK By S.C. Frame; D. Katsis; D. H. Lee; D. Boroyevich; F. C. Lee	[View] [Download]
Abstract: A novel zero-voltage transition (ZVT) three~phase voltage source inverter is proposed and experimentally verified. This topology uses a low-power auxiliary circuit employing inductor feedback. The auxiliary circuit activates for a short period prior to main switch turn-on to achieve ZVT. An advantage of this inductor feedback topology is that the auxiliary devices accomplish ZVT without any modification of the original switch modulation scheme. The proposed soft-switching inverter offers reduced device stress and increased efficiency compared to conventional hard-switched inverters.

	DEVELOPMENT OF A BRUSHLESS DC DRIVE FOR ELECTRIC VEHICLES By P. Van Tichelen; D. Blight; P. Coenen; F. Vermeulen	[View] [Download]
Abstract: This paper describes the development of a high speed (12000 rpm) 44 kW Brushless DC motor, transmission and controller for an electric vehicle with field weakening. Drive train performance, vehicle integration requirements, design trade off and controller functions will be discussed.