필터뱅크 시스템을 이용한 전력신호 품질 해석

Abstract

In power signal quality analyses, accurate detection of harmonics, inter harmonics, triggering points and flicker is important. This paper presents a technique which employ filter bank system, adaptive predictor and recursive algorithm for detecting harmonics, inter harmonics, triggering points and flicker. Filter bank system decompose input signal to sub bands, and then each sub band signals are processed by adaptive predictor. Magnitudes and frequencies of harmonics are estimated at predictor outputs by recursive algorithm. And inter harmonics are detected by the same processing at predictor error terminal. To detect triggering points of power signal event, error signal power change of adaptive predictor is used. In detecting flicker, filter bank composed by three filters is used. The magnitudes and frequencies of each filter outputs are obtained by recursive algorithm, and from these data flicker’s magnitude and frequency are calculated. To asses validities of the method, simulations were performed by synthesized input signals based on IEC standards. And the detecting results were compared with conventional methods.