To reduce costs and the size of a starter generator for an internal combustion engine for starting the engine by operating an electric rotating machine mounted to the internal combustion engine as an electric motor for starting, and for driving an AC load by converting output of the electric rotating machine into AC output with certain frequency after start of the engine.
This starter generator for the internal combustion engine is provided with a drive circuit 4 for supplying a drive current from a DC power supply 6 to armature coils Lu to Lw of the electric rotating machine 2; a rectifying circuit 10 for converting AC voltage induced in the armature coils Lu to Lw into DC voltage; an inverter circuit 5 for converting output voltage of the rectifying circuit 10 into AC voltage; and a changeover switch 11 for switching and connecting input/output terminals 2u to 2w of the electric rotating machine 2 to the drive circuit 4 and the rectifying circuit 10. The changeover switch 11 is controlled, such that at start of the engine, the input/output terminals 2u to 2w are connected to output terminals of the drive circuit 4, and after completion of the start of the engine, the input/output terminals 2u to 2w are connected to input terminals of the rectifying circuit 10.
INABA YUTAKA
NAKAGAWA MASANORI
SUZUKI HIDEAKI
