ARRANGEMENT STRUCTURE OF DRIVE CIRCUIT FOR THREE-PHASE MOTOR

PURPOSE:To shorten the connections between respective FETs and between the FETs and a controlling circuit as well as the matching of the lengths of connections between the same by providing respective semiconductor switching elements (FETs) concentrically around the controlling circuit. CONSTITUTION:In a starter generator S, the FETs 57 of respective power modules 47 are connected directly to a casing 56 through the drains thereof so as to be capable of conduction while respective power modules 47 are arranged concentrically around a controlling circuit 48. According to this method, connections between mutual power modules 47 and between respective power modules 47 and the controlling circuit 48 may be simplified while the lengths of bus bard 53-55, connecting between the power modules 47, may be shortened and the values of resistance of the same may be matched.