多通道表面放电光泵浦源触发特性研究

Trigger characteristic study on optical pumping source with multichannel surface discharge

介绍了多通道表面放电光泵浦源的设计,理论分析了触发电压幅值及上升时间、绝缘基板厚度等参数对所设计光泵浦源触发特性的影响。分析表明:在触发电压作用下,通道两电极处电场出现强烈畸变,而通道中间电场基本为零。采用高速相机拍摄泵浦源的放电图像以及电流线圈测量各通道的放电电流这两种方法实验研究了泵浦源的同步性及放电均匀性。当氮氩混合气体总气压为0.1 MPa(氮氩体积比为3∶7),充电电压20 kV,触发电压30 kV,前沿约10 ns时,成功实现了10通道均匀放电,抖动约20 ns。实验结果表明:在保证放电装置绝缘良好的情况下,若充电电压和触发电压越高,触发电压上升时间越短,触发电极至通道的有效距离越短,则多通道放电的抖动就越小,放电均匀性越好。

A design of an optical pumping source with multichannel surface discharge is introduced. The effects of the trigger voltage and risetime, and the thickness of dielectric substrate on trigger characteristic are analyzed theoretically. The electric field at two electrodes of each channel is intensely deformed, and it is nearly zero at the middle of channels by the action of trigger voltage. Two methods including taking pictures of discharging channels with high-speed multi-frame camera and measuring discharge current with Rogowski coils have been used experimentally to study the discharge synchronism and uniformity of the pumping source. The jitter of about 20 ns of 10 channel uniform discharge is obtained on the conditions of the charging voltage --20 kV, the trigger voltage of 30 kV with the risetime about 10 ns, and the pressure of 0.1 MPa. The results of the experiment indicate that higher charging voltage, smaller risetime of trigger voltage and smaller thickness of dielectric substrate bring smaller jitter and the better uniformity of discharge.