Patent ID: 6659213
Filing Date: 2003-12-09
Classification: B60K,B60L,B60W,Y02T,Y10S

Abstract:
A control device for a hybrid vehicle which comprises an engine as a power source for running the vehicle and a motor/generator, comprising:a high-voltage battery which functions as a power source for the motor/generator; a low-voltage battery for vehicle-mounted electrical loads which has a lower voltage than the high-voltage battery; an inverter for controlling the motor/generator; a sensor which detects a condition of the high-voltage battery; a sensor which detects a rotation speed of the engine; a sensor which detects a vehicle speed; a sensor which detects depression of an accelerator pedal; and a microprocessor which is programmed to: compute a state of charge (SOC) of the high-voltage battery based on the condition of the high-voltage battery; compute a degree of deterioration of the high-voltage battery based on the condition of the high-voltage battery; control a current generated by the motor/generator so that the SOC of the high-voltage battery coincides with a target SOC; vary the target SOC according to the degree of deterioration of the high-voltage battery; determine whether or not the vehicle is decelerating, based on the rotation speed of the engine, the vehicle speed and the depression of the accelerator pedal; and set the target SOC to a low target SOC when the vehicle is not decelerating and to set the target SOC to a high target SOC when the vehicle is decelerating, wherein the low target SOC is lower than the high target SOC.