Control Strategy For An Electric Machine In A Vehicle

摘要

A system and method for controlling an electric vehicle include at least one controller configured to detect an over-voltage condition when an electric-machine voltage exceeds an over-voltage threshold. In response to the over-voltage condition, the electric machine and a variable voltage controller (VVC) are disabled. Upon determining the electric-machine voltage is decreased to at least a second threshold being less than the over-voltage threshold, the controller is configured to set the VVC to a limited-operation mode. Upon determining the electric-machine voltage is decreased to at least a third threshold being less than the second threshold and the over-voltage threshold, the controller is configured to re-enable the electric machine and set the VVC to a normal-operation mode. The limited operation-mode enables the vehicle to maintain vehicle propulsion during the drive-cycle as the electric machine is recovered from a transient condition causing the over-voltage condition.

主权项

1. A method of controlling a hybrid-electric vehicle comprising:
disabling an electric machine and a variable voltage converter (VVC) when an electric-machine voltage exceeds an over-voltage threshold; and upon determining the electric-machine voltage decreased to at least a second threshold being less than the over-voltage threshold: re-enabling the electric machine; and operating the VVC in a normal-operation mode.