A circuit-container unit 22 has a structure in which a board 26, electric components 27 constituting a drive control circuit 24, a frame 28 made of synthetic resin, an insulating plate 29 made of synthetic resin, a shield plate 31 made of aluminum, and a cover 32 made of synthetic resin are stacked over a unit body 25 made of aluminum. The unit body 25 is constituted by a mount part 33 and a plate-like base part 34. Component-container portions 36a and 36b are projected in the lower surface side of the base part 34. The component-container portions 36a and 36b are provided to be projected into a gap between the base part 34 and a motor body. The insides of the component-container portions 36a and 36b serve as container spaces 38. FETs 27a which are short in height are provided on the board 26. Tall capacitors 27b and relays 27c are contained in the component-container portions 36a and 36b. Useless space over the components is thus saved and the space efficiency is improved.