基于S变换与全局最优阈值的暂态扰动信号降噪  

Transient disturbance signals de-noising based on S-transform and optimal global threshold

作　　者：林琳[1] 杨金成[2] 张卫辉[3] 杨永建[2] 王新库 黄南天[3] 

机构地区：[1]吉林化工学院信息与控制工程学院,吉林吉林132022 [2]新疆电力公司电力科学研究院,乌鲁木齐830000 [3]东北电力大学,吉林吉林132012 [4]山东电力公司德州供电公司,山东德州253000

出　　处：《电测与仪表》2015年第23期48-51,共4页Electrical Measurement & Instrumentation

基　　金：国家自然科学基金资助项目(51307020);吉林省科技发展计划项目(20150520114JH);吉林市科技发展计划资助项目(2014064052)

摘　　要：现有的电能质量扰动信号降噪处理方法容易损失信号中包含的高频暂态扰动细节。提出一种基于S变换与全局最优阈值的扰动信号降噪方法。首先,通过S变换获得扰动信号的时-频矩阵;其次,将S变换模矩阵转化为灰度表示;之后,采用Otsu’s算法,计算全局最优阈值,进行滤波降噪;最后,将降噪后的时-频矩阵进行S变换逆变换获得降噪后的扰动信号。仿真实验证明,新方法能够有效保留信号中的高频扰动成分,降噪效果好,能够满足扰动信号分析要求。The details in the high frequency area of transient disturbances signals are always destroyed by current the signal de-noising methods. A new approach of disturbance signals de-nosing based on S-transform and local optimal global threshold has been proposed in this paper. Firstly, the time-frequency matrixes of disturbances signals were cal- culated by the S-transform. Secondly, the amplitudes of S-transform modular matrix were transformed to grey level presentation. Then, the optimal global threshold was chosen by Otsu＇ s algorithm, and the thresholds were used to de- noise the disturbance signals. Finally, the time-frequency matrix after de-noising was transformed into disturbances signals by invert S-transform. The simulation results show that the new method can remain the high frequency elements of the disturbances effectively with excellent de-nosing ability. It could satisfy the requirements of disturbance analysis. signals

关 键 词：电能质量 暂态扰动 S变换 Otsu’s算法 最佳全局阈值 

分 类 号：TM714[电气工程—电力系统及自动化]