Patent ID: 6607142
Filing Date: 2003-08-19
Classification: B60K,F01P,Y10S

Abstract:
A system for controlling coolant flow to cool an electric traction motor and an internal combustion engine of a hybrid electric vehicle (HEV), comprising:an electric coolant pump with an output and a return; a closed coolant flow path connecting to the electric coolant pump output, flowing through the electric traction motor and the internal combustion engine of the HEV to be cooled, and ending at an electric coolant pump return; the electric traction motor and the internal combustion engine having temperature sensors that send temperature signals to an electric coolant pump duty cycle controller; and the controller establishing a duty cycle of the electric coolant pump as a function of temperatures of the electric traction motor and internal combustion engine, wherein at least one of the temperature sensors associated with the electric traction motor generates a signal that is filtered to provide a signal that is adjusted to minimize the effect of rapid excursions in temperature signals.