智能变电站数字采样下双重插值算法对高次谐波测量精度的影响

摘要

With digital sampling in smart substation, sample data synchronization which is sent by the merging unit is necessary for the IEDs. For real-time tracking and measuring the operating frequency of the power system, the sampling data’s resampling is often required by using interpolation algorithm. In order to analyze the error caused by dual interpolation, this paper analyzes the theoretical error of Lagrange and Newton interpolation algorithm, and quantitative analyzes of impact for high order harmonic is provided. The compensation due to interpolation algorithm is calculated according to the analysis. In the end, the method of improving the accuracy of high order harmonic measurement based on interpolation algorithm is proposed.%智能变电站数字化采样之后，间隔层二次设备需要对合并单元发送的SV采样数据作同步插值处理。为实时跟踪测量电力系统的运行频率，计算模块需要通过插值重构的算法进行重采样。为分析双重化插值带来的误差影响，本文详细分析了拉格朗日和牛顿插值算法的理论最大误差，对高次谐波的精度影响进行了量化分析和补偿计算。最后提出了进一步提高插值算法下高次谐波测量精度的思路和方法。