基矛dq变换和S变换的电能质量扰动识别

摘要

For the online identification of power quality disturbances, the paper proposes a method based on dq conversion and S transform. According to the distribution characteristics of the valid values of the disturbance signal, the disturbances are divided into two types firstly. The first type includes voltage sag, swell and interruption. The second type includes oscillation transient, voltage spike, voltage gap and harmonic. It uses valid values waveform characteristics of dq conversion to identify the first type. Then it uses S transform for the second type to get an S matrix and it identifies the second type through the spectrum standard deviation and power frequency amplitude changes of the S matrix. The simulation results show that the method possesses the following features: high accuracy rate of the identification, quick response, simple structure and strong resistance to noises.%针对电能质量扰动的在线识别，提出一种基于dq变换和S变换的电能质量扰动识别方法。首先根据扰动信号电压有效值的分布特性将扰动分为两类：第一类为电压暂降、暂升和中断；第二类为振荡暂态、电压尖峰、电压缺口和谐波。利用dq变换有效值波形特征对第一类扰动进行识别；然后对第二类扰动进行S变换，通过变换后S矩阵的频谱标准差和工频幅值变化进行识剐。仿真结果表明：该方法正确率高、响应速度快、结构简单且抗噪声能力强。