Abstract: A vibration reducing device that reduces the vibration of a control object includes a digital controller. A vibration state detection device detects the vibration of the control object and generates an analog signal of the vibration of the control object. An input-side bandpass filter has a passband that is narrower than a frequency range from a Nyquist frequency to a sampling frequency of the digital controller, and that contains no frequencies that are an integer multiple of the Nyquist frequency of the digital controller. The input-side bandpass filter allows a part of the analog signal that falls within the passband from the analog signal generated by the vibration state detection device to pass. An A/D conversion device converts the analog signal that has passed through the input-side bandpass filter into a digital signal.

Abstract: A controller (20) estimates an internal cylinder pressure of an engine (1) on the basis of the operating conditions of the engine (1), torque variation in the engine (1) is calculated on the basis of the estimated internal cylinder pressure, and an opposite phase torque of the torque variation in the engine (1) is calculated as a torque correction amount. The controller (20) then calculates a torque command value for a motor generator (2) by adding the torque correction amount to a basic torque value for driving the motor generator (2) to rotate, and performs torque control such that the torque of the motor generator (2) equals the torque command value.

Abstract: A vibration reducing device that reduces the vibration of a control object includes a digital controller. A vibration state detection device detects the vibration of the control object and generates an analog signal of the vibration of the control object. An input-side bandpass filter has a passband that is narrower than a frequency range from a Nyquist frequency to a sampling frequency of the digital controller, and that contains no frequencies that are an integer multiple of the Nyquist frequency of the digital controller. The input-side bandpass filter allows a part of the analog signal that falls within the passband from the analog signal generated by the vibration state detection device to pass. An A/D conversion device converts the analog signal that has passed through the input-side bandpass filter into a digital signal.

Abstract: A controller (20) estimates an internal cylinder pressure of an engine (1) on the basis of the operating conditions of the engine (1), torque variation in the engine (1) is calculated on the basis of the estimated internal cylinder pressure, and an opposite phase torque of the torque variation in the engine (1) is calculated as a torque correction amount. The controller (20) then calculates a torque command value for a motor generator (2) by adding the torque correction amount to a basic torque value for driving the motor generator (2) to rotate, and performs torque control such that the torque of the motor generator (2) equals the torque command value.