为了稳定可靠地触发CO2激光器旋转火花开关, 设计了一套高压脉冲触发系统并且提出了一种新型的绝缘栅双极晶体管(IGBT)驱动与保护方法。根据CO2激光器中旋转火花开关的触发结构, 应用复杂可编程逻辑器件(CPLD)芯片EPM3512开发了可以输出100～500 Hz重频脉冲信号以及单次脉冲信号的触发信号源; 应用光耦HCPL-3120设计了具有过流、过压保护功能兼有电磁兼容(EMC)设计的IGBT驱动电路; 对高压脉冲变压器进行建模并通过PSPICE软件仿真; 搭建了实验平台, 进行了联机性能测试。实验结果表明: 在500 Hz的重复频率下, 高压脉冲触发系统可连续稳定地输出高于38 kV的高压重频脉冲, 基本满足CO2激光器的旋转火花开关稳定可靠触发的要求。

To trigger the rotated spark switch in a CO2 laser stably and reliably, a high-voltage pulse trigger system is designed and a new method for driving and protecting Insulated Gate Bipolar Transistor(IGBT) is proposed. According to the trigger structure of rotated spark switch in the CO2 laser, a pulsed source which can output 100-500 Hz repetition-rate pulses and a single pulse is developed with the EPM3512 CPLD chip and the IGBT drive circuit with over-current, over-voltage protection and Electromagnetic Compatibility(EMC) design is proposed by a optocoupler HCPL-3120. Besides, the model of a high-voltage pulse transformer is simulated by PSPICE software. Finally, an experimental platform is buit to test the system performance online. Experimental results indicate that the high-voltage pulse trigger system can output high-repetition-rate pulses higher than 38 kV continuously and stably, which satisfies the requirements of the rotated spark switch in the CO2 laser for stability and reliability.