采样法交流电参量测量的误差分析

摘要

For the sampling measurement of AC electrical parameters, the errors are mainly caused by discrete sampling and digital quantization. By analyzing the randomicity of sampling and quantization, the measurement errors of AC electrical parameters are presented using the standard deviation formulas of RMS voltage, RMS current and active power etc. The theoretical correctness is examined by the numerical simulation and the deviation between the result of the numerical simulation and the theoretical value is analyzed for weak signal.%基于采样法对交流电参量进行测量,信号的离散采样和数字量化是引入测量误差的主要因素. 分析了采样和量化的随机特性,借助能反映采样和量化影响的相应电参量的标准差给出了有效值和有功功率等主要交流电参量测量的误差公式. 通过数值仿真验证了理论的正确性,并分析了小信号情况下误差的仿真结果偏离理论值的原因.