Apparatus for providing controlled mechanical braking torque

• US 5,442,276 A
• Filed: 02/22/1993
• Issued: 08/15/1995
• Est. Priority Date: 03/27/1989
• Status: Expired due to Term

• Current Assignee: Integrated Technology Corporation
• Original Assignee: Integrated Technology Corporation
• Inventors: Schwartz, Rodney E., Clauter, Steven T., Orman, Gary M.
• Primary Examiner(s): KINCAID, KRISTINE LYNN
• Application Number:
  US08/021,275
• Time in Patent Office: 904 Days
• Field of Search: 322/10, 322/29, 322/25, 322/32, 322/35, 322/40, 322/100
• US Class Current: 322/25
• CPC Class Codes: H02P 3/06 for stopping or slowing an individual dynamo-electric motor or dynamo-electric converter

Abstract

Apparatus and method for electrically generating mechanical braking torque employs direct field drive incorporating an AC alternator plus a current regulator. The stator windings of the alternator are directly coupled to the field winding via a full wave rectifier and the current regulator. The invention simplifies electrical circuitry for generating braking torque, provides wide dynamic range of torque generation, limits voltages and currents to easily manageable levels, and reduces mechanical drive train requirements. The invention produces a constant power mechanical load from essentially 0 to over 1,000 watts from an alternator of the size typically used for automotive applications.

Claims

1. An electrical apparatus for generating a mechanical braking torque, comprising:

an electro-mechanical device which generates electrical energy as a function of a mechanical input using at least one winding, said at least one winding being lossy; and

means for dissipating substantially all said electrical energy in said at least one winding to generate said mechanical braking torque.

2. The electrical apparatus of claim 1, said electro-mechanical device comprising a device selected from the group consisting of an alternator, a generator and a motor acting as a generator.

3. The electrical apparatus of claim 1, wherein said electro-mechanical device is an alternator and said at least one winding is a field winding of said alternator.

4. The electrical apparatus of claim 1, wherein said electro-mechanical device is a wound field motor and said at least one winding is a field winding of said wound field motor.

5. The electrical apparatus of claim 4, wherein said wound field motor is a series wound motor.

6. The electrical apparatus of claim 4, wherein said wound field motor is a shunt wound motor.

7. The electrical apparatus of claim 4, wherein said wound field motor is a DC motor.

8. The electrical apparatus of claim 1, wherein said electro-mechanical device is a DC motor.

9. The electrical apparatus of claim 1, wherein said electro-mechanical device is a permanent magnet type DC motor and said at least one winding comprises an armature winding of said permanent magnet type motor.

10. The electrical apparatus of claim 1, wherein said at least one winding comprises a plurality of lossy windings and said means for dissipating causes substantially all said electrical energy to be dissipated in said plurality of windings to generate said braking torque.

11. The electrical apparatus of claim 1, further comprising current regulator means for regulating the flow of current in said electro-mechanical device in order to control the amount of said mechanical braking torque.

12. The electrical apparatus of claim 11, said current regulator means comprising a resonant mode power controller.

13. The electrical apparatus of claim 12, said resonant mode power controller comprising at least one of a capacitor and an inductor for temporarily storing energy associated with said current.

14. The electrical apparatus of claim 11, said current regulator means comprising a pulse-width modulated current regulator.

21. The electrical apparatus of claim 1, said electro-mechanical device comprising AC alternator means for generating said electrical energy as a function of said mechanical input, rectifier means for rectifying the output from said AC alternator means to provide a rectified DC output, and current regulator means for controlling the amount of current which flows from the alternator output and back into the field of the alternator, said alternator means and current regulator means being coupled such that current induced in the stator flows back into the field winding, and said at least one winding comprising at least one of said stator and said field winding.

15. An electrical apparatus for generating a mechanical braking torque, comprising:

an electro-mechanical device having a winding for generating an electrical current as a function of a mechanical input, said winding being lossy; and

means for directing substantially all of said electrical current into said winding to result in said mechanical braking torque.

16. The electrical apparatus of claim 15, said electro-mechanical device comprising a device selected from the group consisting of an alternator, a generator and a motor acting as a generator.

17. The electrical apparatus of claim 15, further comprising current regulator means for regulating the flow of current in said electro-mechanical device in order to control the amount of said mechanical braking torque.

18. The electrical apparatus of claim 17, said current regulator means comprising a resonant mode power controller.

19. The electrical apparatus of claim 18, said resonant mode power controller comprising at least one of a capacitor and an inductor for temporarily storing energy associated with said electrical current.

20. The electrical apparatus of claim 17, said current regulator means comprising a pulse-width modulated current regulator.