PURPOSE: To provide a failure detector of rotating electric machine which can detect a partial discharge signal and its generating location with high accuracy by discriminating partial discharge from radio noise generated while a rotating electric machine is running.
CONSTITUTION: Plural partial discharge sensors 9 is mounted onto the slots of respective phases of a stator winding 4 to detect partial discharge in the slots. Output signals from the partial discharge sensors 9 are filtered by a filter circuit 23, and by a noise discriminating circuit 25 provided with a peak hold circuit 30, a delay circuit 33, a time comparison circuit 32, and an eliminating circuit 34, radio noise is discriminated from a partial discharge signal based on a time difference between respective detected signals of the partial discharge sensors 9 to specify a partial discharge generating location. Processing is carried out by a partial discharge generation processing circuit 26 according to the partial discharge generated, and processed results appear on a display 28.
TOKURA HIDEKI
HAYASHI KENJI
TANAKA TAKAO
KANEDA KICHIJI
ITO KEIICHI
KIMURA TAKESHI
KITAMURA SHIGEO
MITSUBISHI ELECTRIC CORP