基于虚拟αβ静止坐标系的相角测量算法

A Phase Angle Measurement Algorithm Based on Virtual αβ Stationary Coordinate

根据离散傅里叶变换算法在异步采样条件下产生相角误差的机理,利用αβ静止坐标系中正序相量的2种表示形式,构建具有2个反相β轴的虚拟αβ静止坐标系,提出了一种将3个数据窗离散傅里叶变换结果乘以不同系数后合成的相角测量新算法。该算法能有效地削减传统离散傅里叶变换相角测量误差中的动态部分,再经由固定补偿,得到精确的相角测量结果。仿真结果表明,该算法准确度高、运算量小,具有良好的实时性。

According to the phase error mechanism on the asynchronous sampling condition of discrete Fourier transform（DFT）,a virtual αβ stationary coordinate contained two reversed-phase β axis is constructed by utilizing two forms of positive sequence component expression under αβ stationary coordinate.A new phase measurement algorithm synthesized with different proportion of three data window DFT results multiplied by different coefficients is proposed,which could greatly eliminate the dynamic part of phase measurement error of traditional DFT.After compensating the fixed offset,we can get the precise phase angle measurement results.The simulation results show that the proposed algorithm has high accuracy,small computation and real-time performance.