CAJ | 학술논문

S变换是具有自适应分辨率的时频变换，近年来在电能质量分析中得到广泛应用。但是由于传统S变换计算量大(时间复杂度O(N3))，很难满足实时性要求。将一种新的S变换的快速算法(fast S-transform，FST)(时间复杂度O(N3 log N))用于电能质量分析：对不同电压扰动在 FST 域的辨识；对含有噪声电压扰动去噪；与传统S变换运行效率进行对比。仿真结果表明不同的电压扰动在 FST 域内系数有不同表现形式；对于有噪声的电压扰动消噪后，能够较好地恢复原有时域电压信号。从计算时间和所占内存来看，该算法具有较好的实时性。
S변환시구유자괄응분변솔적시빈변환，근년래재전능질량분석중득도엄범응용。단시유우전통S변환계산량대(시간복잡도O(N3))，흔난만족실시성요구。장일충신적S변환적쾌속산법(fast S-transform，FST)(시간복잡도O(N3 log N))용우전능질량분석：대불동전압우동재 FST 역적변식；대함유조성전압우동거조；여전통S변환운행효솔진행대비。방진결과표명불동적전압우동재 FST 역내계수유불동표현형식；대우유조성적전압우동소조후，능구교호지회복원유시역전압신호。종계산시간화소점내존래간，해산법구유교호적실시성。
S transform is a time-frequency transform with adaptive resolution, which is widely used in analyzing the power quality recently. However,the traditional S transform is very computation-intensive( O(N3) time complexity) and difficult to meet the real-time requirements. A new fast S transform (FST) algorithm (O(NlogN) time complexity) is introduced to analyze the power quality, which can differentiate the different voltage disturbances in the FST domain, and denoise the voltage disturbances. Compared with the traditional S-transform in terms of efficiency, simulation results show that the different voltage disturbances have different coefficient manifestations in the FST domain, and the original time-domain voltage signal is recovered after the voltage noise disturbances are suppressed with FST algorithm. The FST algorithm shows better real-time in view of computational time and memory share.