基于改进S变换的电力系统谐波检测方法  

Detection of harmonics in power system based on modified S-transform

作　　者：肖助力[1] 龚仁喜[1] 陈双[1] 于槟华 贾僖泉 

机构地区：[1]广西大学电气工程学院,广西南宁530004

出　　处：《电力系统保护与控制》2015年第3期84-90,共7页Power System Protection and Control

基　　金：国家自然科学基金(60962008)~~

摘　　要：快速而准确地检测出谐波是实现电力系统谐波治理的前提条件,对提高电能质量具有重要的意义。提出了一种基于改进S变换的电力系统谐波检测方法。该方法在S变换的高斯窗函数中引入了三个参数p、q、?,根据输入信号的不同设置合适的参数,提取谐波成分、幅值、暂态发生的起止时间等特征信息。首先介绍了改进S变换的基本原理及特性;其次详细阐述了改进S变换应用于电力系统谐波检测的方法;最后分别对稳态、暂态及噪声环境下的谐波进行了仿真实验。仿真结果验证了该检测方法的有效性,同时也表明:该方法性能好、精度高,在信噪比较低的情况下仍能达到满意的检测效果,具有一定的抗噪声干扰能力。Rapid and correct detection of harmonics is the premise of suppressing harmonics in power system, and is also of great significance to the improvement of power quality. A new detection method for the harmonics based on a modified S-transform（MST） is proposed, in which three parameters of p, q and λ are introduced into the Gaussian window function in conventional S-transform（ST）. According to the differences of the input signal, suitable parameters of Gaussian window are selected to extract the characteristic quantities of harmonics such as harmonic order, amplitude, and the start and end time of transient state, etc. The fundamental principle and characteristics of the MST are firstly presented, and then the detection method of harmonics in power system based on MST is elaborated in detail. Finally, the steady harmonics, transient harmonics and the harmonics with noise are simulated respectively. The simulation results verify the efficiency of the proposed method, and show that it is also characterized by simple utilization, high accuracy, and good anti-interference performance. Furthermore, the method can be also used for the detection of the power harmonics under the condition of low signal noise ratio（SNR）.

关 键 词：电力系统 谐波检测 改进S变换 高斯窗 稳态 暂态 

分 类 号：TM935[电气工程—电力电子与电力传动]