Parallel hybrid vehicle employing parallel hybrid system, using both internal combustion engine and electric motor generator for propulsion

摘要

In a parallel hybrid vehicle employing a parallel hybrid system, using both an internal combustion engine and an electric motor generator for propulsion, a desired motor/generator torque is map-retrieved based on both the engine speed and throttle opening from a predetermined characteristic map in a fashion of feedforward processing. The signal indicative of the desired motor/generator torque is subjected to a low-pass filter that passes signals included in a frequency band lower than an oscillation frequency of powertrain torsional vibrations to remove the powertrain vibration frequency components. The map is preprogrammed so that the desired motor/generator torque is set at zero in a specified speed range lower than an engine idle speed. In another specified speed range from the engine idle speed to a predetermined direct-coupling engine speed that permits the motor/generator to be directly coupled with the engine, a gain of the desired motor/generator torque is set to increase with an increase in the engine speed. In a specified speed range above the predetermined direct-coupling engine speed, the motor/generator is coupled directly with the engine, so that the motor/generator torque output produced from the motor/generator is substantially identical to the engine torque output.