Patent ID: 6829556
Filing Date: 2004-12-07
Classification: B60L,H02P,Y02T

Abstract:
A method for operating an electrical system of a propulsion drive system for a vehicle including an electrical machine to predict an incipient fault in the electrical machine, comprising:generating a neutral-to-ground leakage signal representative of current between a neutral point of the machine and an electrical ground; sensing a temperature of the electrical system; determining if the sensed temperature exceeds a temperature criteria of the electrical system, said temperature criteria corresponding to a temperature condition indicating that the electrical system is operating at a temperature and for a period of time which dissipates any moisture; operating the electrical system at a reduced power condition if the leakage signal exceeds a selected threshold and the sensed temperature does not exceed the temperature criteria; and operating the electrical system at normal power conditions if the leakage signal is below the selected threshold.