触发回路对主动型保护间隙保护性能的影响

Influence of Trigger Circuit on Protection Performance of Active Protection Gap

为了进一步研究主动型触发回路对浪涌保护间隙(surge protection gap,SPG)保护特性的影响,针对主动触发回路中各元件所起的作用进行了实验研究。实验结果表明:触发回路中压敏电阻未动作前,主要是通过自身的静态电容与串联电容进行分压的;增加触发回路中的压敏电阻,SPG击穿电压的增加量为增加压敏电阻的动作电压;压敏电阻U1mA电压值越小,SPG的保护范围就越宽,但压比K值越小;随着气体放电管(gas discharge tube,GDT)击穿电压的增加,SPG的击穿电压增加,但是GDT的击穿电压越小,SPG的保护范围越宽,SPG响应时间受GDT的影响较大;随着电容容量的增加,SPG击穿电压增加,但保护范围基本不变。研究结果可为主动型过电压保护间隙触发回路性能的优化提供实验基础。

In order to further study the effect of active trigger circuit on the protection characteristics of surge protection gap(SPG),we experimentally studied the effect of each component in the active trigger circuit.The experimental results show that the voltage of piezoresistor in the trigger circuit is dividually loaded by the static capacitance and the series capacitor before the action.When the piezoresistor in the trigger circuit is added,the increment in the SPG breakdown voltage is the action voltage of the piezoresistor.The smaller the U1mA voltage of piezoresistor is,the wider the SPG protection range will be,however the smaller the ratio-voltage K is.With the increase of the breakdown voltage of gas discharge tube(GDT),the breakdown voltage of SPG increases,but the smaller the GDT breakdown voltage is,the wider the SPG protection range will be,and the response time of SPG is greatly influenced by GDT.The breakdown voltage of SPG increases with the increase of capacitance,but the scope of the protection is not changed basically.The research results can provide an experimental basis for optimizing the performance of the active overvoltage protection gap trigger circuit.