CVT谐波传变特性及其影响因素的优化研究

Optimization of CVT harmonic propagation characteristics and influencing factors

电容式电压互感器(CVT)在用于谐波测量时受杂散电容、补偿电抗器电感值的影响较大,杂散电容等影响因素在选值不精确时会对谐波测量结果带来附加误差。为降低CVT谐波测量误差,提出一种基于函数映射关系的CVT输入参数优化方法。该方法以计算结果的误差最小为条件,输入参数的置信度最大为目标,在满足幅值、相移最小误差要求下选择置信度最大的输入参数组合,并基于测量不确定度对输入参数进行评定,通过实际案例验证分析了该方法的合理性和有效性。

Capacitive voltage transformer(CVT)is greatly affected by stray capacitance and inductance of compensating reactor when it is used for harmonic measurement.During the research process,it was found that influencing factors such as stray capacitance can cause harmonics when the value is not accurate.Wave measurement results introduce additional errors.In order to reduce the CVT harmonic measurement error,a method for optimizing CVT input parameters based on the function mapping relationship is proposed.The method is based on the minimum error of the calculation result and the maximum confidence of the input parameter as the goal.In order to meet the requirements of amplitude and phase shift minimum error,the input parameter combination with the greatest confidence is selected,and the input parameters are evaluated based on the measurement uncertainty.Finally,the validation and analysis of actual cases prove the rationality and effectiveness of the method.