Torque transmission device and method of reducing effects of torque pulsations

Torque pulsations generated in the torque of an engine are obtained from detection signals from a crankshaft angle detection sensor and an engine water temperature detection sensor at the time of an engine starting operation. A control unit controls an MG1 via a drive circuit so that a damping torque of the same phase as the torque pulsations is generated, and ensures that the torque pulsations of the engine are not transmitted to a ring gear from a planetary carrier.