In this paper,a new method with high accuracy for electric harmonic estimation is presented.First,the CZT (Chirp Z-transform) is used to extract the parameters (amplitude,frequency and phase) of fundamental frequecy signals precisely from the multifrequency signals of power system.Second,after subtracting the fundamental frequency signal from the multifrequency signals,the harmonic signals are truncated with the Blackman window and their spectrums are calculated by fast Fourier transform (FFT).Then,according to the fundamental frequency,each frequency harmonic is calculated.At last,interpolating on the frequency domain of the Blackman window,the parameters (amplitude and phase)of each frequency harmonic signals can be calculated precisely.The simulation results show that the proposed method almost has the same estimation accuracy with the method which is based on double-spectrum-line interpolation FFT,but the new method only costs about half computation times.%提出了一种电力谐波高精度估计的新方法.首先使用CZT (Chirp Z变换)从含有谐波的电力信号中高精度提取基波相量,并从中减去基波信号；然后加布莱克(Blackman)窗截断电力信号,用快速傅里叶变换(FFT)计算出剩余信号的频谱；再依据基波频率精确估计出各谐波的频率；最后依据各谐波频率对Blackman窗函数在频域插值,精确计算出各电力谐波的参数.仿真试验表明,该方法与加窗双谱线插值FFT分析电力谐波方法有基本同等的估值精度,但计算量约为1/2.
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