Parameter optimized method for generalized S-transform algorithm and its application in the analysis of power quality disturbances

Abstract

Aiming at the difficulties of optimizing parameter r for generalized S-transform (GST), a parameter optimized method for generalized S-transform is proposed and applied to the classification and detection of the power quality disturbances. The value of r for the fundamental frequency is set independently so as to reveal the time disturbance, convenient to optimize the values of r for other frequencies on the concentration of frequency disturbance. So the time-frequency disturbances characteristics can be obtianed simultaneously in desireable resolution. The evaluating indicators for determining r are put forward so as to provide the theoretical basis to determine r adaptively. Based on the time-frequency matrix of this method, four disturbance characteristics are presented for classification by the decision tree classifier. The disturbance parameters such as starting and ending time, disturbance amplitude and harmonic components are further detected in this study. The experiment analysis and the application to real power engineering demonstrate that the method has good noise robustness and satisfactory accuracy.