高电压脉冲下BNC型组合电路退耦电阻选用的研究

Study of the Selection of Decoupling Resistor in BNC Type Combination Circuit

针对由气体放电管和双向抑制瞬态二极管组成的BNC型组合电路的配合问题,用Haefely PSURGE 6.1设备产生幅值为1 k A、2 k A的8/20μs电流波形冲击BNC型电路,改变退耦电阻的阻值,结果表明退耦电阻的增大可以缩短电路启动时间以及减小双向抑制瞬态二极管上的残压,退耦电阻增大到一定值后,双向抑制瞬态二极管的残压便不再减小,达到拐点值。用罗氏线圈套在气体放电管上监测放电管中流过的电流波形,用两个探头分别测量气体放电管和双向抑制瞬态二极管中的残压波形,根据波形来判断BNC型电路工作过程,分析负向尖峰形成的原因。

Aiming at the marching problem of the gas discharge tubes and the BNC type combination circuit made of dual suppression transient diode, the Haefelay PSURGE 6.1 is used to generate 8/20 μs impulse currents with peak of 1 k A and 2 k A and the value of the decoupling resistance in BNC type circuit is changed. The results show that, the increasing of the decoupling resistance would shorten the starting time of the circuit and reduce the residual voltage across the dual suppression transient diode; But, after the decoupling resistance increases to a certain value, the residual voltage would not decrease and reaches the turning point. The current through the discharge tube is measured by Rogowski coil, while the residual voltages across the gas discharge tube and the dual suppression transient diode are measured by probes respectively. Then the working process of the BNC circuit is judged and the cause of negative peak is analysed.