摘要
现有基于插值FFT算法的间谐波检测方法需已知信号频率分布来进行结果修正,存在明显的不足。提出一种基于插值线性调频Z(Chirp Z Transform CZT)变换的间谐波分析方法。该方法在不增加采样长度的情况下,可获得较准确的间谐波信号频率分布估计值,通过调整CZT输出序列的值,使CZT结果等价于DFT结果,利用基于Rife-Vin-cent(III)窗的插值修正公式对CZT结果进行修正,可得到较精确的间谐波参数。仿真证明该方法明显优越于插值FFT的间谐波检测方法,具有一定理论价值和现实意义。
A method for interharmonic estimation based on interpolation Chirp Z Transform （CZF） is presented comparing with interpolated FFT which has to acquire the interharmonic frequency of signal to correct results of FFT. Under the situation of not increasing sampling length N, CZT can obtain mere accurate frequency distribution estimated value. In this foundation, CZT output sequence M is adjusted to make the CZT result be equal to the DFT result, therefore, Rife - Vincent （ Ⅲ ） window can be used to correct CZT results and mere precise interhamonic parameeter can be obtained. The simulation results have verified the effectiveness of the algorithm.
出处
《四川电力技术》
2007年第4期9-13,共5页
Sichuan Electric Power Technology
