Vehicle power flow analysis to distinguish between internal faults and external forces

• US 10,005,363 B1
• Filed: 02/24/2017
• Issued: 06/26/2018
• Est. Priority Date: 02/24/2017
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Correia, Josef J., Park, Jeong J., Rieland, Helen M., Kulas, Richard A.
• Primary Examiner(s): Ismail, Mahmoud S
• Application Number:
  US15/442,100
• Time in Patent Office: 487 Days
• Field of Search: 701 22
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/14 Acceleration
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/80 Time limits
• CPC Class Codes: B60L 2250/26 by pedal actuation
• CPC Class Codes: B60L 3/0007 Measures or means for preventing or attenuating collisions
• CPC Class Codes: B60L 3/0061 relating to electrical machines
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60L 3/12 Recording operating variables ; Monitoring of operating variables
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility

Abstract

A method of analyzing vehicle parameters to distinguish between whether an unexpected vehicle acceleration is due to an internal fault or external forces. The method uses a magnitude and direction of a change in acceleration for evaluating whether the unexpected acceleration is due to a potential system fault scenario or a potential crash scenario.

Claims

1. A method of analyzing vehicle parameters to distinguish between internal faults and external forces for a vehicle having an electric motor drive system operable to hold the vehicle stationary by applying a holding torque with the electric motor drive system without application of a braking system, comprising:

determining if there is an unexpected significant rate of change in vehicle acceleration;

based upon a determination that there is an unexpected rate of change in vehicle acceleration, determining whether there is a corresponding unexpected change in electric motor drive system holding torque above a predetermined level;

based upon a determination that there is an unexpected change in electric motor drive system holding torque above a predetermined level, determining if a direction of the change in electric motor drive system holding torque is in a same direction as vehicle travel;

based upon a determination that the direction of the change in electric motor drive system holding torque is in a same direction as vehicle travel, taking predetermined measures for evaluating a potential electric motor drive system fault scenario including at least one of bringing the vehicle to a stop and/or disabling the vehicle operation; and

based upon a determination that the direction of the change in electric motor drive system holding torque is in an opposite direction as vehicle travel, taking predetermined measures for a potential vehicle crash scenario including allowing the vehicle to continue to operate, wherein the predetermined measures for a potential vehicle crash scenario differ from the predetermined measures for evaluating a potential electric motor drive system fault scenario.

2. The method according to claim 1, wherein the predetermined measures for a potential crash scenario including allowing the vehicle to continue to operate, further includes engaging a parking brake after a first distance threshold is exceeded.

3. The method according to claim 1, wherein the predetermined measures for a potential crash scenario including allowing the vehicle to continue to operate, further includes shifting the vehicle to park after a predetermined threshold distance is exceeded.