EPE Association: EPE 1991 - 36 - Session 4.3: TRACTION 2

EPE 1991 - 36 - Session 4.3: TRACTION 2
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1991 - Conference > EPE 1991 - 36 - Session 4.3: TRACTION 2

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   PWM CURRENT SOURCE CONVERTER-INVERTER SYSTEM FOR RAILWAYS APPLICATION
By S. Nonaka; K. Yamasaki; S. Hirohata [View]
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Abstract: The drive system of pararell induction motors, which is composed of a single-phase converter and a three-phase current source inverter, is presented. This system has sinusoidal input and output voltage/current and input power factor is unity. One of the marked point is to have auxiliary GTO's. With the auxiliary GTO's, a sinusoidal pulsewidth modulation (PWM) can be performed easily. PWM strategies are applied to both the converter and inverter. The PWM patterns for the converter reduces switching frequency and switching losses in half. The harmonics of the input current are experimentally investigated in various circuit parameters. And the experimental results of steady state, acceleration and deceleration according to the inverter frequency command, and load step change characteristics of the system are reported.

   SYNCHRONOUS DRIVE FOR MOTORIZED WHEELS WITHOUT GEARBOX FOR LIGHT RAIL SYSTEMS AND ELECTRIC CARS
By G. Braga; A. Farini; F. Fuga; R. Manigrasso [View]
[Download]

Abstract: Rolling stock for light rail systems working in the center of historical European cities can be built according to a conventional design provided the platform is conveniently low and the wheels are independent. These measures allow ease of passenger movement with low noise and good commercial speed even over tortuous routes. The paper shows that these goals can be achieved using permanent magnet synchronous motors which are englobed in and integral with each wheel (without gearbox interposition) and steering each wheel by means of a proper power converter, this motorized wheel can also be used in electric or hybrid cars with the same structural simplifications.

   COMPACT ELECTRICAL POWER SUPPLY FOR ON-BOARD USE
By M. Krüger; W. Leonhard [View]
[Download]

Abstract: Autonomous vehicles, whether freely mobile, tracked, levitated or airborne, need electrical on-board power supplies for the various loads, either for auxiliary purposes, such as instrumentation and control, or for the main drive. Since electrochemical storage batteries are still unsatisfactory with regard to energy content, volume, weight and cost, there is continuous need for compact, light-weight on-board power supplies based on liquid or gaseous fuel. This problem is studied once more with a view towards a turbo-driven high-speed generator which is connected through a switched transistor converter to a DC-link buffered by a battery of reduced size. A directly coupled gas turbine, operating under optimal conditions with regard to fuel consumption and emissions, might eventually be used as a prime mover. This paper deals only with the electromechanical side of the scheme. Some experimental results are discussed in the paper.

   A STUDY ON THE POWER SUPPLY SYSTEM FOR THE SUPERCONDUCTING MAGLEV TRANSPORT
By E. Masada; H. Ohsaki; A. Seki [View]
[Download]

Abstract: The power supply system of the long-stator linear synchronous drive is studied for the superconducting maglev transport in relation with the utility network, d.c. intermediate system construction, power feeding circuits to stator sections, the current waveform and the influence on superconducting magnets. To suppress the load variation against the utility network, the d.c .linkage of converter stations is preferable for the practical system. The regulation of the waveform of the stator current is analyzed, considering the effect of feeding circuits and arrangement of coils on the basis of forces acting on the superconducting magnets. With the developnent of high-power GTO inverter, the construction of such power supply system is concluded to be well feasible for practical operation required by train service and utility networks.

   THREE LEVEL INVERTER DSC CONTROL STRATEGY FOR TRACTION DRIVES: PART 1 - THEORY AND SIMULATION RESULTS
By V. Cascone; L. Mantica; M. Oberti [View]
[Download]

Abstract: An improvement of the ETR 500 traction drive is obtained eliminating the input DC-DC converter stage and feeding the power inverter directly by the 3 kV overhead supply line. A three-level GTO power converter configuration and particular control methods are needed in order to reduce the negative effects due to harmonic injection in the supply line and in the signalling equipments. Actually the best results are obtained with a Direct Self Control technique. Aim of this paper is to analyse the features of a three-level power converter feeding asynchronous traction motor, with DSC control strategy . The simulations show the typical waveforms of this drive besides some peculiarities like fast dynamic response and the harmonic contents. This study has been carried out with the aid of EMTP (Electro-Magnetic Transient Program) for both control system and power electronic circuits.

   A VARIABLE-SPEED BRUSHLESS DOUBLY-FED AUTOMOTIVE ALTERNATOR
By Virendra Javadekar; Ravi D.K.; René Spée; Alan Wallace [View]
[Download]

Abstract: The loads on the electrical systems of automobiles are projected to increase significantly in the near future. This will result in a requirement for improved efficiency over the claw-pole or Lundell generators which to date have been employed in cars for approximately twenty years. The alternative system proposed in this paper is based on a machine with two sets of stator windings, for power generation and excitation respectively, and a cage-like rotor without electrical contacts. Regulation of the output voltage is provided by a pulse-width-modulated converter operating with adjustable magnitude and adjustable frequency and with reversible phase sequence for operation over a wide speed range. The system design is examined and test results from an experimental prototype are compared with both model predictions and the performance of a conventional generator.

EPE 1991 - 36 - Session 4.3: TRACTION 2
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1991 - Conference > EPE 1991 - 36 - Session 4.3: TRACTION 2
	[return to parent folder]

	PWM CURRENT SOURCE CONVERTER-INVERTER SYSTEM FOR RAILWAYS APPLICATION By S. Nonaka; K. Yamasaki; S. Hirohata	[View] [Download]
Abstract: The drive system of pararell induction motors, which is composed of a single-phase converter and a three-phase current source inverter, is presented. This system has sinusoidal input and output voltage/current and input power factor is unity. One of the marked point is to have auxiliary GTO's. With the auxiliary GTO's, a sinusoidal pulsewidth modulation (PWM) can be performed easily. PWM strategies are applied to both the converter and inverter. The PWM patterns for the converter reduces switching frequency and switching losses in half. The harmonics of the input current are experimentally investigated in various circuit parameters. And the experimental results of steady state, acceleration and deceleration according to the inverter frequency command, and load step change characteristics of the system are reported.

	SYNCHRONOUS DRIVE FOR MOTORIZED WHEELS WITHOUT GEARBOX FOR LIGHT RAIL SYSTEMS AND ELECTRIC CARS By G. Braga; A. Farini; F. Fuga; R. Manigrasso	[View] [Download]
Abstract: Rolling stock for light rail systems working in the center of historical European cities can be built according to a conventional design provided the platform is conveniently low and the wheels are independent. These measures allow ease of passenger movement with low noise and good commercial speed even over tortuous routes. The paper shows that these goals can be achieved using permanent magnet synchronous motors which are englobed in and integral with each wheel (without gearbox interposition) and steering each wheel by means of a proper power converter, this motorized wheel can also be used in electric or hybrid cars with the same structural simplifications.

	COMPACT ELECTRICAL POWER SUPPLY FOR ON-BOARD USE By M. Krüger; W. Leonhard	[View] [Download]
Abstract: Autonomous vehicles, whether freely mobile, tracked, levitated or airborne, need electrical on-board power supplies for the various loads, either for auxiliary purposes, such as instrumentation and control, or for the main drive. Since electrochemical storage batteries are still unsatisfactory with regard to energy content, volume, weight and cost, there is continuous need for compact, light-weight on-board power supplies based on liquid or gaseous fuel. This problem is studied once more with a view towards a turbo-driven high-speed generator which is connected through a switched transistor converter to a DC-link buffered by a battery of reduced size. A directly coupled gas turbine, operating under optimal conditions with regard to fuel consumption and emissions, might eventually be used as a prime mover. This paper deals only with the electromechanical side of the scheme. Some experimental results are discussed in the paper.

	A STUDY ON THE POWER SUPPLY SYSTEM FOR THE SUPERCONDUCTING MAGLEV TRANSPORT By E. Masada; H. Ohsaki; A. Seki	[View] [Download]
Abstract: The power supply system of the long-stator linear synchronous drive is studied for the superconducting maglev transport in relation with the utility network, d.c. intermediate system construction, power feeding circuits to stator sections, the current waveform and the influence on superconducting magnets. To suppress the load variation against the utility network, the d.c .linkage of converter stations is preferable for the practical system. The regulation of the waveform of the stator current is analyzed, considering the effect of feeding circuits and arrangement of coils on the basis of forces acting on the superconducting magnets. With the developnent of high-power GTO inverter, the construction of such power supply system is concluded to be well feasible for practical operation required by train service and utility networks.

	THREE LEVEL INVERTER DSC CONTROL STRATEGY FOR TRACTION DRIVES: PART 1 - THEORY AND SIMULATION RESULTS By V. Cascone; L. Mantica; M. Oberti	[View] [Download]
Abstract: An improvement of the ETR 500 traction drive is obtained eliminating the input DC-DC converter stage and feeding the power inverter directly by the 3 kV overhead supply line. A three-level GTO power converter configuration and particular control methods are needed in order to reduce the negative effects due to harmonic injection in the supply line and in the signalling equipments. Actually the best results are obtained with a Direct Self Control technique. Aim of this paper is to analyse the features of a three-level power converter feeding asynchronous traction motor, with DSC control strategy . The simulations show the typical waveforms of this drive besides some peculiarities like fast dynamic response and the harmonic contents. This study has been carried out with the aid of EMTP (Electro-Magnetic Transient Program) for both control system and power electronic circuits.

	A VARIABLE-SPEED BRUSHLESS DOUBLY-FED AUTOMOTIVE ALTERNATOR By Virendra Javadekar; Ravi D.K.; René Spée; Alan Wallace	[View] [Download]
Abstract: The loads on the electrical systems of automobiles are projected to increase significantly in the near future. This will result in a requirement for improved efficiency over the claw-pole or Lundell generators which to date have been employed in cars for approximately twenty years. The alternative system proposed in this paper is based on a machine with two sets of stator windings, for power generation and excitation respectively, and a cage-like rotor without electrical contacts. Regulation of the output voltage is provided by a pulse-width-modulated converter operating with adjustable magnitude and adjustable frequency and with reversible phase sequence for operation over a wide speed range. The system design is examined and test results from an experimental prototype are compared with both model predictions and the performance of a conventional generator.