PURPOSE: To eliminate an exciting transformer by rectifying the AC voltage induced in a stud and employing the rectified output current as exciting power source.

CONSTITUTION: A fastening stud 3 is passed through a hole made through a laminated stator core 1, then a stator is tightened from the opposite ends through springs 11 and secured to a stator frame. Induced voltage is taken out through a cable 12 from one end of the fastening stud 3 the other end of which is neutral-grounded through a press ring 11 and the section between the press ring 11 and the cable 12 is insulated by an insulator 2. The induced voltage is applied to a thyristor rectifier 9 where it is rectified and excites the exciting winding 8 of an AC exciter 6. Voltage generated from the AC exciter 6 is rectified through a rotary rectifier 7 in order to excite a generator field winding 5. By such arrangement, power can be generated from the generator 4 without requiring an exciting transformer.