基于数字信号处理器的加窗插值算法在电网谐波检测中的应用

Application of Window Interpolation Algorithm Based on Digital Signal Processor in Power Grid Harmonic Detecting

提出运用快速傅里叶变换(fast Fourier transform,FFT)加窗插值算法进行电网谐波检测的数据处理。首先介绍了FFT和加窗插值算法的原理,并对比加窗前后的频谱图;然后利用MATLAB软件对模拟电量信号进行仿真,结果显示频谱泄漏明显减少;最后将该算法应用于数字信号处理器中,对实际的电力系统相关电量进行分析和计算,经过FFT加窗插值算法处理后的谐波幅值和相位与实际值基本吻合,说明该算法对电网信号的数据处理精度较高。

This paper proposes to use fast Fourier transform ＆window interpolation algorithm to proceed data process for power grid harmonic detecting. It firstly introduces principles of FFT and window interpolation and compares spectrogram before and after using window interpolation. Then it uses MATLAB software to proceed simulation for analog electric quan- tity signals and results show obvious decrease of spectrum leakage. At last it applies this algorithm in digital signal processor to analyze and calculate related electric quantity of the power system. It discovers harmonic amplitudes and phases after be- ing processed by using FFT and window interpolation algorithm are identical to practical values which indicate that this algo- rithm is able to improve data processing precision of power grid signals.