基于快速提升小波变换的谐波实时检测新方法

A novel real-time harmonic detection method using fast lifting wavelet transform

提出一种基于提升小波变换的有源电力滤波器谐波实时检测方法.以经典Daubechies小波为谐波检测基函数,利用欧拉算法因子化分解得到其第二代小波提升步骤;通过当前采样值与历史采样值构造改进型数据帧实现小波实时算法,并采用周期延拓处理数据帧边界.搭建dSPACE试验平台,自编Simulink/Embedded Matlab Function函数实现检测算法,将Simulink/RTW和dSPACE/RTI生成C代码载入实时硬件系统进行分析.试验结果表明:该方法能准确实时地分离出电网稳态谐波分量,暂态跟踪调整时间少于一个周波;较第一代Mallet小波算法加速近一半;改进的实时数据帧构造方法硬件实现更加快速.

A new real-time harmonic detection method for active power filters based on lifting wavelet transform was proposed. A classical Daubechies wavelet primary function was factored into lifting steps of second generation wavelet using Euclidean algorithm for harmonic analysis. The improved real-time frame operation algorithm can avoid the reconstruction of data frames by joining the current sample values with history data in succession. Period extension method was adopted in lifting wavelet process and resolving data edge influence. Real-time harmonic detection algorithm was constructed by self-writing Simulink/ Embedded Matlab. The C codes, which were generated from Simulink/RTW and dSPACE/RTI tools, were loaded into dSPACE real-time hardware system, and the analysis was completed. Experimental resuits show that the proposed method can abstract harmonic component accurately, reduce the control tran- sient adjusting time to less than one period wave, and achieve hardware implementation rapidly. It is proved that the lifting wavelet transform algorithm can save half of time compared with the first generation wavelet mallet algorithm.