| 摘要 |
<p>PROBLEM TO BE SOLVED: To detect the whole of a stator winding by providing a first detecting means arranged close to the stator winding and a second detecting means connected to the first detecting means in series and arranged inside a frame housing the stator winding. SOLUTION: A partial discharge detector for a dynamo-electric machine is provided with a first detecting means 6 arranged close to a stator winding 4b and constructed of a metal conductor, a second detecting means 7 arranged in a frame 2 and constructed of a metal conductor, and a partial discharge measurement device 8 connected to them and provided with a deterioration determining means 12. When partial discharge is generated in an insulating part 15 in the stator winding 4b, first high frequency current is propagated by electromagnetic coupling or electrostatic coupling so as to be detected by the first detecting means 6. On the other hand, electromagnetic waves are radiated from the insulating part 15, from which discharge is generated, and detected as the second high frequency signal by the detection means 7. From a pulse frequency above a predetermined intensity in a predetermined frequency band of the detected respective high frequency signals, a deterioration state in each coil is determined by means of the deterioration determining means 12.</p> |
