杂散电容对CVT谐波测量影响的处理方法研究

电容式电压互感器(CVT)在用于谐波电压测量时受杂散电容的影响较大。通过对杂散电容的变化特点的分析,利用CVT的等效电路,本文提出了一种由输入输出传变关系的数据映射,在杂散电容可能的变化区间内,依据数理统计理论,以测量数据置信度为优化条件,校正误差最小为优化目标的数学处理方法确定杂散电容参数的优化组合,从而实现对谐波电压校正测量的方法,并通过实际案例的验证分析证明了方法的合理性和有效性。

Study on the Processing Method of Influence of Stray Capacitance on CVT Harmonic Measurement

Capacitive voltage transformers(CVT)are subject to greatstray capacitance in the harmonic voltage measurement.In this paper,a kind of data mapping of input-output transfer relationship is proposed by the analysis of variation characteristics of stray capacitance and by the use of equivalent circuit of CVT so to,within the possible variation interval of stray capacitance,define the optimization combination of stray capacitance parameters in accordance with theory of mathematical statistics and with the confidence coefficient of measurement data as optimization condition and minimum corrector error as optimization target so to achieve the correction measurement method of harmonic voltage.And the reasonableness and effectiveness of the method are proved through the verification analysis of actual case.