ANALYSIS OF POWER QUALITY DISTURBANCE IN DISTRIBUTION NETWORK BY WAVELET TRANSFORM

Wavelet transform (WT) possesses good localized time-frequency characteristics. Using WT the time-frequency characteristics of signals can be extracted simultaneously. Here the power quality disturbances caused by the switching of circuit breakers, the saturation of transformers and the power electronic devices are analyzed by WT. It is verified by simulation analysis that the characteristic information of disturbances can be well extracted by WT. Therefore, the basis for detecting, evaluation, classification of harmonics and the improvement of power quality is provided.