PACCAR Inc
Systems and methods for reducing noise, vibration, and/or harshness during engine shutdown and restart

Abstract:

In some embodiments of the present disclosure, an electric motor is used to generate correction torques to counteract unwanted torque pulses generated by an internal combustion engine during startup and/or shutdown. In some embodiments, the electric motor may be mounted to an accessory drive such as a power take-off mechanism or a front end accessory drive (FEAD). In some embodiments, the correction torques may be used to enforce an engine speed target profile for startup or shutdown, and may be determined using a feedback control loop based on the engine speed. The correction torques help to reduce or eliminate noise, vibration, and/or harshness (NVH) during startup and/or shutdown.