| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a partial discharge detection device for a rotary electric machine capable of controlling automatically the detection level of partial discharge corresponding to the change of the signal level of partial discharge. SOLUTION: This partial discharge detection device is equipped with a partial discharge sensor for outputting a signal of partial discharge, an attenuator for attenuating the signal, a narrow-band-pass filter for removing a noise from the signal, an amplifier for amplifying the signal and outputting it as a first signal, a detection level control circuit for generating a second signal corresponding to a generation frequency of the partial discharge based on the first signal, an analog/digital converter for converting the second signal into a digital signal, and a computer for housing the second signal. The narrow-band-pass filter controls the detection level of the second signal in the range having the center frequency of 5 MHz-40 MHz and the bandwidth of 1 MHz-3 MHz, and the detection level control circuit executes the same control so that a generation frequency reference value set beforehand becomes the same value as a generation frequency value of the second signal.</p> |
