一种提高智能变电站PMU相量测量精度的改进采样值调整算法

Improved sampled value adjustment algorithm increasing measurement precision of smart substation PMU

提出了一种适用于智能变电站应用环境下提高同步相量测量单元(PMU)测量精度的采样值调整算法。算法基于三次样条插值和时标变换,实现了过程总线采样数据与PMU算法的无缝连接。该算法减小了过程层定采样频率下系统频率偏移带来的离散傅里叶变换(DFT)算法频谱泄漏误差,同时可有效减小过程总线采样值传输丢包对相量算法精度的影响。在智能变电站应用环境下利用MATLAB对所提算法进行仿真,结果验证了其不受频率偏移和采样值丢包的影响,能保证PMU相量测量的高精度。

An improved adjustment algorithm of sampled value is proposed to increase the measurement precision of smart substation PMU,which applies the cubic spline interpolation and time scale transformation to realize the seamless join of the values sampled by process bus with the PMU algorithms.The spectrum leakage error of DFT algorithm due to system frequency deviation with fixed frequency sampling at process level is thus reduced and the influence of transmission data loss on the precision of PMU algorithm is also weakened.The proposed algorithm is simulated with MATLAB in smart substation environment and the results demonstrate that it is immune to the frequency deviation and transmission data loss and can guarantee precision of PMU measurement.