金属氧化物避雷器交流幅频特性的实验研究

摘要

在建立以非线性电阻和非线性电容并联的等效电路模型做为金属氧化物避雷器的等效电路模型基础上,推导了响应电流关于激励电压的时域表达式,参照激励电压通过确定的方法将响应电流分解为阻性部分和容性部分.通过对金属氧化物避雷器阀片在不同幅值、不同频率正弦激励电压下交流响应的实际测量,得到不同幅值与频率下激励电压和响应电流的时域波形并对其分析,获得不同激励电压幅值下响应电流、阻性电流有效随随频率变化的曲线以及不同频率下电流密度和电位移与电场强度关系曲线,并且对不同频率下电流密度和电位移与电场强度关系曲线进行了归一化处理分析其非线性程度,探究了交流正弦电压激励下不同幅值、频率对金属氧化物避雷器介电性能的影响.%Based on the equivalent circuit model of nonlinear resistor and nonlinear capacitance as the basis of the equivalent circuit model of the MOA,in this paper,time domain expression of response current about the applied voltage is derived and the response current is decomposed into resistive part and capacitive part by determinate method.Through the actual measurement of AC response under different amplitude and frequency sinusoidal applied voltage,the time domain waveforms of applied voltage and response current under different amplitude and frequency are obtained.The relationship curves of response current and resistive current versus frequency under different applied voltage amplitude and the relationship curves of current density and electric displacement versus electricfield under different frequencies are obtained.Then the relationship curves of current density and electric displacement versus electric field were normalized to analyze the nonlinear degree.The influence of different amplitude and frequency on the dielectric properties of MOA under AC sinusoidal applied voltage is explored.