8/20μs冲击电流发生器源阻抗对压敏电阻器性能表征的影响研究

Influence of Source Impedance of 8/20 μs Impulse Current Generator on the Performance Characterization of Varistor

文中研究了不同源阻抗8/20μs冲击电流对压敏电阻冲击能量的影响规律。建立了8/20μs冲击电流发生器电路模型,进行了电路仿真研究;搭建了8/20μs冲击电流实验平台,对不同规格的压敏电阻进行冲击电流实验。研究结果表明:随着8/20μs冲击电流源阻抗减小,相同冲击电流幅值下通过压敏电阻的冲击能量增加;随着压敏电阻直流参考电压增加,冲击电流源阻抗对压敏电阻冲击能量的影响作用增强,但随着冲击电流幅值的提高,冲击电流源阻抗对通过压敏电阻冲击能量的影响作用减弱。因此,在一定冲击电流幅值以下的8/20μs冲击电流试验中,冲击电流发生回路的源阻抗不能选择的太小。研究结果对压敏电阻冲击电流测试的规范化具有一定的理论与工程应用价值。

The effect of 8/20 μs impulse current generator with different source impedance on the impact energy of varistor was analyzed. A circuit model of 8/20 μs impulse current generator was established to conduct circuit sim- ulation.Then,the experiment platform for 8/20 μs impulse current generator was set up to conduct impulse current test for the varistors with different specifications. The results show that the smaller the source impedance of 8/20 μs impulse current generator is, the larger the impact energy through the varistor in the same impulse current amplitude is;the higher the DC reference voltage of the varistor is, the stronger the effect of the source impedance on the impact energy is.However,with the increase of the impulse current amplitude, the effect of the source impedance on the impact energy weakens.Therefore,for the 8/20 μs impulse current test under a certain impulse current ampli- tude, the source impedance of the impulse current generator cannot be too small.This study may provide theoretical and engineering support for standardization of the impulse current test on varistor.