불평형전류 측정에 의한 회전기 열화감시장치

초록

This paper described an on-line condition monitoring device for rotating machines by measurement of unbalance current due to insulation deterioration. The device consists of a zero-phase current transformer (ZCT), a low-noise amplifying circuit, and a microprocessor unit. The prototype device measures current of 500 μA ~ 30 mA in frequency ranges from 10 Hz to 3 kHz. An application experiment was carried out on 3-phase induction motors and we could measure current changes caused by a short-circuited turn.