Regenerative braking controller for a DC motor

• US 3,947,739 A
• Filed: 08/28/1973
• Issued: 03/30/1976
• Est. Priority Date: 08/30/1972
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Narita, Hiroshi, Horiuchi, Michimasa
• Primary Examiner(s): Schaefer, Robert K.
• Assistant Examiner(s): Duncanson, Jr., W. E.
• Application Number:
  US05/392,296
• Time in Patent Office: 945 Days
• Field of Search: 318/258, 318/269, 318/370, 318/371, 318/373, 318/376, 318/377, 318/380, 318/381, 307/239, 307/240
• US Class Current: 318/376
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 9/00 Electric propulsion with power supply external to the vehicle electric propulsion for monorail vehicles, suspension vehicles or rack railways B60L13/00; in combination with batteries or fuel cells within the vehicle B60L50/53
• CPC Class Codes: H02P 3/14 by regenerative braking

Abstract

A regenerative braking controller for use with a series-wound DC motor which drives an electric car for railways or electric automobile and which is controlled by a thyristor chopper comprises a series-connected circuit including an armature of the DC motor, a field winding thereof and a smoothing reactor, a chopper connected in parallel with said series-circuit, a diode connected between said parallel circuit and a power supply, and a gate controller for applying a gate signal to said chopper in succession only during a period of time when said chopper is to be rendered conductive.

Claims

1. A regenerative braking controller for use with a DC motor, comprising a series-connected circuit including an armature of the DC motor, a field winding thereof and a smoothing reactor;

a thyristor chopper connected in parallel with said series-circuit and including at least a main thyristor and a commutation thyristor for turning off said main thyristor;

a diode connected between said parallel circuit and a power supply; and

a gate controller means for applying a gate signal to the gate of said main thyristor continuously during the period of time when said chopper is to be conductive and applying a pulse signal to the gate of said commutation thyristor at the end of said period of time.

2. A regenerative braking controller for use with a DC motor as set forth in claim 1, further comprising an auxiliary excitor for energizing said field winding at the beginning of the regenerative braking cycle.

3. A regenerative braking controller as set forth in claim 1, wherein said gate controller means comprises two gate transformers each including an input coil, an output coil and a resetting coil;

two sets of series-connected circuits each including a switching element and said input coil of the gate transformer connected to a DC power supply;

a series-connected circuit including an impedance element and said resetting coil connected to said DC power supply;

control means for alternately turning on and off the switch elements of said two sets of series-connected circuits; and

an output circuit for summing logic outputs from said two gate transformers.

4. A regenerative braking controller as set forth in claim 1, wherein said gate controller means comprises a phase shifter means for providing outputs during a period of time when said chopper is to be rendered conductive depending on a deviation of motor current from an instructed value of current, and an oscillator means for generating pulses during the time when said phase shifter means produces said outputs.

5. A regenerative braking controller as set forth in claim 3, wherein said resetting coils of the two gate transformers are connected in series.

6. A regenerative braking controller as set forth in claim 3, wherein said impedance element is a resistor.

7. A regenerative braking controller as set forth in claim 3, wherein said switching element is a transistor.

8. A regenerative braking controller as set forth in claim 3, wherein said output circuit is constituted by a diode.