Control system for a hybrid vehicle for improving regenerative braking efficiency while avoiding engine stalls during regenerative braking

摘要

A control system for a hybrid vehicle including a traction motor with a regenerative braking function. In order to increase the efficiency of regeneration, engine brake during regenerative braking is reduced by lowering the rotational speed of the engine below the lowest rotational speed value of the conventional control system. The control system can avoid engine stall during sudden, rapid deceleration which may occur during regenerative braking. Rapid deceleration of the vehicle is detected based on operating conditions of the vehicle. The traction motor has an assisting function where the traction motor drives the engine to help prevent a stall. The assisting function is carried out by controlling torque output from the traction motor to a predetermined positive value upon detection of the quick deceleration of the vehicle. The predetermined positive value is preset according to the operating characteristics of the vehicle's clutch.