电能质量分析仪谐波测量频谱分析长度检测

Method for test of FFT window width of voltage harmonic in power quality analyzers

提出了一种电能质量分析仪谐波测量频谱分析长度的检测方案。根据国家标准对谐波测量的要求和谐波分析的软硬件原理得出通过检测频率分辨率达到检测目的的方法,这需要检测仪器是否采用谐波子组测量和矩形加权窗函数。文中根据分组的原理得出子组测量的检测方法;根据傅里叶变换、频谱泄露和栅栏效应的原理得出频率分辨率的检测方法;根据加窗函数减少频谱泄露的原理,通过公式推导和Matlab计算得出检测加窗算法的方法。综合以上实现电能质量分析仪频谱分析长度的检测。并通过大量的实验验证了该检测方法的正确性和检测方案的可行性。

The length of spectrum analysis test about harmonic analysis in power quality analyzer has been studied. The method is in accordance with the harmonic measurement request of standard and the harmonic analysis theory. The core is to test the frequency resolution which can be reacted from the output values. We need to detect the har-monic subgroup measurement according to the grouping theory. And we also check the weighting form which can re-alize by the different spectral leakage using rectangular weighting and others. After knowing these we can know the window width. The correctness of this method and the viability of this solution have been verified by many test ex-periments.