基于傅里叶变换的高精度频率及相量算法

A High-Precision Algorithm for Frequency and Phasor Based on Fourier Transform

离散傅里叶变换(DFT)是电力系统中频率及相量测量的基本算法,作者首先从理论上分析了传统的离散傅里叶算法存在的测量误差,并在传统的离散傅里叶算法的基础上提出了一种前向递推的DFT算法,该算法利用3点DFT数据进行频率及相量的测量,有效减小了运算量,仿真试验验证了所提算法的正确性。仿真结果还表明,该算法能有效地减小由傅里叶算法引起的测量误差,具有测量精度高的优点。

Discrete Fourier transform （DFT） is the basic method for the measurement of frequency and phasor of power system. In this paper the authors firstly analyze the measuring error existing in traditional DFT algorithm; then based on conventional DFT propose a forward recursive DFT algorithm in which the frequency and phasor can be measured by use of three data derived from DFT, thus the operation amount can be effectively reduced. The correctness of the proposed algorithm is validated by simulation. Simulation results also prove that the measuring error caused by conventional DFT can be effectively reduced and the measuring accuracy of the proposed algorithm is high.