适用于同步相量测量的DFT算法研究

讨论了用于同步相量测量的离散傅氏变换DFT(Discrete Fourier Transform)算法。传统DFT算法计算量大，不适于采样率高且测量量多的场合。给出了一种递归傅氏变换算法，可减少计算量，并由此算法而推出一种频率测量方法，可以灵敏、准确地反映系统频率变化。将该算法用于所开发的同步相量测量装置中，实验结果表明该算法正确，且能满足精度要求。

Study of DFT algorithm in synchronized phasor measurement

The DF T(Discrete Fourier Transform)algorithm for synchronized phasor measurement is discussed.The non-recursive DFT has great computation work,which can't be used conveniently in the cases with high sampling rate or multiple measuring elements.A new recursive DFT is proposed,which reduces the computation work obviously.A frequency measurement method based on it is gi-ven,which reflects the frequency deviation of power system sensitively and accurately.The recursive DFT has been applied in a PMU(Phasor Measurement Unit)and the experimental results show that this algorithm is correct and meets the precision requirement.