Method and system for fail-safe motor operation

• US 6,965,206 B2
• Filed: 12/02/2002
• Issued: 11/15/2005
• Est. Priority Date: 10/13/2000
• Status: Expired due to Term

• Current Assignee: Deka Products Limited Partnership
• Original Assignee: Deka Products Limited Partnership
• Inventors: Kamen, Dean, Field, J. Douglas, Morrell, John B., Robinson, David W., Sachs, Jason M., Heinzmann, John David, LeMay, Philip, Meyer, Steven R., Reich, Ronald K.
• Primary Examiner(s): Ro, Bentsu
• Application Number:
  US10/307,892
• Publication Number:
  US 20030146025A1
• Time in Patent Office: 1,079 Days
• Field of Search: 318/139, 318/434, 318/490, 318/563, 388/903, 180218-220, 180/7.1, 180/65.1, 180/198, 180/443, 180/446, 324/500, 324/772, 361 23- 34
• US Class Current: 318/139
• CPC Class Codes: A63C 17/12 with driving mechanisms
• CPC Class Codes: B60K 7/00 Disposition of motor in, or adjacent to, traction wheel roller-skate driving mechanisms A63C17/12
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B62D 57/00 Vehicles characterised by having other propulsion or other ground- engaging means than wheels or endless track, alone or in addition to wheels or endless track sledges B62B; motor sledges B62M
• CPC Class Codes: B62K 11/007 Automatic balancing machines with single main ground engaging wheel or coaxial wheels supporting a rider
• CPC Class Codes: H02P 29/032 Preventing damage to the motor, e.g. setting individual current limits for different drive conditions
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y10S 388/903 Protective, e.g. voltage or current limit

Abstract

An electric device includes a motor and a motor drive for commanding a torque generated by the motor. A fault control circuit detects a fault condition associated with the motor drive. Upon detection of the fault condition, the fault control circuit adjusts the torque commanded by the motor drive.

Claims

1. An electric device comprising:

a motor;

a motor drive for providing, under non-fault operating conditions, one or more desired line-to-line voltages to the motor; and

a fault control circuit for detecting a fault condition associated with the motor drive, the fault control circuit adjusting a pulse duty-cycle of a signal applied to a winding of the motor upon detection of the fault condition to substantially preserve at least one of said desired line-to-line voltages.

2. The electric device according to claim 1, wherein the motor has redundant winding sets.

3. The electric device according to claim 1, wherein the fault condition is a failed component associated with the motor drive, the failed component being one of a winding, a CPU, and a RAM.

4. The electric device according to claim 1, wherein the electric device is a transporter and the motor is coupled to at least one ground contacting element of the transporter so as to propel the transporter.

5. The transporter according to claim 4, herein the transporter is a dynamically stabilized transporter that is statically unstable with respect to tipping.

6. The electric device according to claim 1, wherein the fault condition pertains to a switch associated with the motor drive.

7. The electric device according to claim 6, wherein the switch is a transistor.

8. An electronic device comprising:

a motor having a winding;

a motor drive for commanding the motor; and

a fault control circuit for detecting a fault condition associated with the motor drive, the fault control circuit includes at least one squib for decoupling the motor drive from the winding upon detection of the fault condition, such that the winding is electrically isolated from the motor drive.

9. A method for controlling an electric device, the electric device including a motor driven by a motor drive, the motor drive for providing, under non-fault operating conditions, one or more desired line-to-line voltages to the motor, the method comprising:

detecting a fault condition associated with the motor drive; and

adjusting a pulse duty-cycle of a signal applied to a winding of the motor upon detection of the fault condition to substantially preserve at least one of said desired line-to-line voltages.

10. The method according to claim 9, wherein the fault condition pertains to a switch associated with the motor drive.

11. The method according to claim 10, wherein the switch is a transistor.

12. An electric device comprising:

a load;

a power converter for providing, under non-fault operating conditions, one or more desired line-to-line voltages to the load; and

a fault control circuit for detecting a fault condition associated with the power converter, the fault control circuit adjusting a pulse duty-cycle of a signal applied to a terminal of the load upon detection of the fault condition to substantially preserve at least one of said desired line-to-line voltages.

13. The electric device according to claim 12, wherein the load is a motor that includes redundant winding sets.

14. The electric device according to claim 12, wherein the fault condition is a failed component associated with the power converter, the failed component being one of a winding, a CPU, a switch, and a RAM.

15. The electric device according to claim 12, wherein the electric device is a transporter and the load is coupled to at least one ground contacting element of the transporter so as to propel the transporter.

16. The transporter according to claim 15, wherein the transporter is a dynamically stabilized transporter that is statically unstable with respect to tipping.

17. A method for controlling an electric device, the electric device including a load driven by a power converter, the power converter for providing, under non-fault operating conditions, one or more desired line-to-line voltages to the load, the method comprising:

detecting a fault condition associated with the power converter; and

adjusting a pulse duty-cycle of a signal applied to the load upon detection of the fault condition to substantially preserve at least one of said desired line-to-line voltages.

18. The method according to claim 17, wherein the load is a motor that includes redundant winding sets.

19. The method according to claim 17, wherein detecting the fault condition includes detecting a failed component associated with the power converter, the failed component being one of a winding, a CPU, a switch, and a RAM.

20. The electric device according to claim 17, wherein the electric device is a transporter and the load is coupled to at least one ground contacting element of the transporter so as to propel the transporter.

21. The transporter according to claim 20, wherein the transporter is a dynamically stabilized transporter that is statically unstable with respect to tipping.