基于新型自卷积窗和插值补偿的采样方法研究

Research on Sampling Method Based on New Self-Convolution Window and Interpolation Compensation

针对电学计量中双通道交流电压信号幅值、相位差精确测量的要求,采用加窗函数法、离散傅里叶变换(DFT)对信号进行解析处理。考虑到非整周期条件下采样的双路信号序列通过DFT后的结果存在较大泄漏误差,提出利用一种新型卷积窗和插值补偿算法,以消除谐波对基波幅值测量引人的误差,并补偿基波本身泄露而引人的误差;将双路信号的同时采样和插值补偿算法结合,消除双路信号间的相位差的测量误差。仿真结果和实际测量结果比较表明:所提出的方法能够有效地消除谐波对基波的影响,更精确地测量双路信号的基波幅值以及其之间的相位差。该方法可应用于对幅值、相位差进行连续测量且测量精度要求较高的场合,还可作为核心计算方法应用于虚拟仪器技术之中。

In view of the electrical measurement,double channel AC voltage signal amplitude and phase difference measurement requirements,use window function method and discrete Fourier transform(DFT)to analytical processing of signal,under the condition of considering the whole cycle sampling the results of two-way signal sequence by DFT is leakage error,using a new type of window convolution and interpolation compensation algorithm,the introduction of the base amplitude value is used to eliminate the harmonic measurement error,and compensate the error of the leak and the introduction of fundamental wave itself;The simultaneous sampling and interpolation compensation algorithm are combined to eliminate the measurement error of the phase difference between the two signals.The comparison between the simulation results and the actual measurement results shows that the proposed method can effectively eliminate the influence of harmonics on the fundamental wave,and more accurately measure the fundamental wave amplitude and phase difference between the double-channel signals.This method can be applied to the continuous measurement of amplitude and phase difference with high precision and can also be used as a core calculation method in virtual instrument technology.