氧化锌压敏电阻在不同电流环境下老化规律研究

Research on the Degradation of Carbon Resistors in Different Current Conditions

通过试验室模拟氧化锌压敏电阻在不同电流环境下的老化过程,依据氧化锌压敏电阻的非线性特性与双肖特基势垒理论分析试验现象,得到其老化规律:在直流老化中正反向压敏电压与漏电流参数呈不对称变化,温度线性上升;交流老化中正反方向压敏电压与漏电流呈对称变化,温度呈上升-稳定-上升的趋势;冲击老化中压敏电压呈上升-稳定-急速下降的趋势,漏电流以稳定-急速上升的趋势变化,非线性系数始终下降的变化规律.该结论在氧化锌压敏电阻避雷器的使用和检测中具有一定参考意义.

The degradation of carbon resistors was simulated under different current conditions in laborato‐ry .The results of the experiment were analyzed according to the nonlinear characteristics of the carbon re‐sistor and the double Schottky barrier theory .In direct current degradation ,forward and reverse varistor voltage and leakage current were asymmetric ,and the temperature showed a linear increase .In alternating current degradation ,forward and reverse varistor voltage and leakage current were symmetric ,and the temperature changed in an increasing‐stability‐dropping pattern .In impulse current degradation ,the varis‐tor voltage showed an increasing‐stability‐dropping trend and the leakage current exhibited a stability‐rock‐eting trend ,w hile the nonlinear coefficient steadily declined .T he above conclusion should be of reference significance in the application and testing of carbon resistor surge protective devices .