Active vibration control system for hybrid vehicle

An active vibration control system for use in a hybrid vehicle having a generator motor for assisting an engine in rotating a crankshaft thereof, comprising:

• a basic signal generator for generating a harmonic basic signal from a rotational frequency of the crankshaft;
• an adaptive notch filter for being supplied with said basic signal and outputting a control signal;
• a combiner for combining said control signal and a drive signal for said generator motor with each other and supplying a combined signal to said generator motor;
• an error signal detector for detecting a rotational speed fluctuation of the crankshaft and outputting an error signal representative of the detected rotational speed fluctuation;
• a corrective filter for being supplied with said basic signal and outputting a reference signal, said corrective filter having a transfer function of said generator motor;
• and
• filter coefficient updating means for being supplied with said error signal and said reference signal and successively updating a filter coefficient of said adaptive notch filter so that said error signal will be minimized,
• wherein the control signal effects only frequencies relative to the rotational speed fluctuation of the crankshaft, and the drive signal is representative of a motor assistance signal, and
• wherein the system suppresses a torque fluctuation of the crankshaft in response to the torque fluctuation without detriment to a response of the motor assistance signal.