Abstract: A starting apparatus for an engine has a plurality of cylinders and an output shaft. The apparatus includes a power supply, an inverter having a switching element, a motor generator, an ECU, A crank angle sensor. The motor generator is coupled to the output shaft and connected to the power supply through the inverter. The ECU energizes the motor generator by controlling the inverter when the engine is started. The ECU causes ignition to occur in a specific cylinder that contains air-fuel mixture and is in an expansion stroke in an engine stopping state. The crank angle sensor indirectly detects a rotational speed of the motor generator. After the ignition caused, the ECU prohibits the motor generator from being energized until the rotational speed detected reaches or exceeds a predetermined value. As a result, the apparatus curbs an excessive increase in the temperature of a switching element.

Abstract: There is provided a generator system for internal combustion engines, which can produce power efficiently at all times irrespective of the engine speed even for use in an internal combustion engine operated at variable speeds such as a vehicle engine. An AC generator electronic control unit (ACG.ECU) 3 determines a rotation speed N2 of a rotating electromagnetic field to be generated by a rotor 1R based on a mechanical rotation speed N1 of the rotor 1R in an alternator 1 such that the relative speed N of the rotating magnetic field to a stator 1S agrees with the maximum efficiency speed of rotation Nx. Then the ACG.ECU 3 sends the determined value to a rotating electromagnetic field controller 2a. The rotating electromagnetic field controller 2a controls phases of AC power to be supplied to a three-phase coil 11 of the rotor 1R to generate a rotating electromagnetic field with the rotation speed N2.