光学学报, 2017, 37 (3): 0314002, 网络出版: 2017-03-08
3 kW射频板条CO2激光器多电极放电均匀性与阻抗匹配性
Discharge Uniformity and Impedance Matching of Multi-Group Electrodes for 3 kW Radio Frequency Slab CO2 Lasers
激光器 3 kW射频板条CO2激光器 多组电极放电模型 均压电感 放电均匀性 阻抗匹配 lasers 3 kW radio frequency slab CO2 lasers multi-group electrode discharge model shunt inductors discharge uniformity impedance matching
摘要
针对3 kW大功率射频板条CO2激光器的多组电极放电均匀性与阻抗匹配性问题, 采用麦克斯韦时域差分法构建了多组电极下的放电模型, 获得了最佳放电均压效果的均压电感值。以放电区等效阻抗值为基础结合均压电感值得到极板放电的总负载阻抗值。利用总负载阻抗值并通过Smith圆图获得与之对应的匹配网络阻抗参数, 使总负载阻抗与匹配网络阻抗之和为纯电阻50 Ω, 实现射频输入功率的完全馈入。实际测得当放电均匀与阻抗匹配时驻波比为1.18。研究结果表明, 在时域差分法模型中增加匹配的均压电感后, 极板整体放电均匀性波动从之前的15%降低到2.8%, 且每组电极的放电均匀性差异控制在0.3%以内。放电实验表明, 在放电均匀且阻抗匹配情况下, 对应激光器输出功率为3.1 kW, 且在2 h内波动可稳定在±1%以内。
Abstract
As for the discharge uniformity and impedance matching problems during multi-group electrode discharge at 3 kW high-power radio frequency (RF) slab CO2 lasers, the multi-group electrode discharge model is built with the Maxwell time domain difference method and the shunt inductor value is gained under the optimum discharge uniformity efficiency. The impedance of total load in the discharge electrode is calculated with the combination of the shunt inductor value and the equivalent impedance of discharge area. The impedance matching network parameters are given with the Smith circle and the impedance of total load, and the sum of impedance of total load and matched network impedance is 50 Ω which makes the RF input power completely fed. The actual measured standing wave ratio (SWR) is 1.18 when the discharge uniformity and impedance matching are satisfied simultaneously. The results show that, with the matched shunt inductors added in the time domain difference method, the fluctuation of the overall discharge uniformity of electrode slab decreases from previous 15% to 2.8% and the discharge uniformity difference between each electrode group is within 0.3%. The discharge experiment shows that, under the discharge uniformity and impedance matching conditions, the laser output power of 3.1 kW within 2 h can be stable with the fluctuation within ±1%.
王振, 彭浩, 王炜, 吴超, 唐霞辉. 3 kW射频板条CO2激光器多电极放电均匀性与阻抗匹配性[J]. 光学学报, 2017, 37(3): 0314002. Wang Zhen, Peng Hao, Wang Wei, Wu Chao, Tang Xiahui. Discharge Uniformity and Impedance Matching of Multi-Group Electrodes for 3 kW Radio Frequency Slab CO2 Lasers[J]. Acta Optica Sinica, 2017, 37(3): 0314002.