【摘要】 针对传统S变换存在时频分辨率低且计算量大的问题，该文提出一种基于最优Bohman窗的改进S变换。该方法通过直接控制窗长获得最优时频分辨率，同时只针对主要频率点进行时频分析，实现对各类扰动信号特征的精确快速提取。首先根据所提评价标准确定最优长度参数；其次将采样信号进行快速傅里叶变换得到FFT频谱，再通过基于极大值包络的动态测度快速算法确定主要频率点；然后根据主要频率点所处频段选择对应最优长度参数进行计算处理；最后根据模时频矩阵计算时频幅值向量完成时频特征提取。仿真分析和实验结果表明，所提方法相较于传统S变换具有更高的时频分辨率和更短的计算时间，适用于电能质量扰动信号特征的精确快速提取。更多还原

【Abstract】 Focusing on the problems of low time-frequency resolution and large amount of calculation in the traditional S-Transform, a modified S-Transform based on the optimal Bohman window is proposed. In order to extract accurately and quickly the characteristics of all kinds of disturbance signals, this method obtains the optimal time-frequency resolution by controlling directly the window length and carries out time-frequency analysis only for the main frequency points. Firstly, the optimal length parameter is determined according to the proposed evaluation criteria. Secondly, the sampled signal spectrum is obtained through fast Fourier transform, and then the main frequency points are determined by the dynamic measurement fast algorithm based on the maximum envelope; Then the corresponding optimal length parameter is selected according to the frequency band of the main frequency point for calculation and processing; Finally, the time-frequency feature extraction is completed by calculating the time-frequency amplitude vector based on modulus time-frequency matrix. Simulation analysis and experimental results show that the proposed method has higher time-frequency resolution and shorter calculation time than the traditional S-Transform, and is suitable for the accurate and fast extraction of power quality disturbance signal features.更多还原