为了提高非链式脉冲DF激光器注入能量和放电稳定性,研究了火花针紫外预电离放电引发非链式脉冲DF激光器的电路特性。通过分析工作气体中SF6分子的碰撞解离及其对电子的吸附过程,得到了电子连续性方程,结合放电回路基尔霍夫方程建立了描述DF激光器放电特性的数学模型。运用该模型模拟了预电离放电电压、主放电电压及电流随时间的变化关系,模拟结果较真实地反映了预电离放电与主放电之间的时间延迟、主电极间的击穿及自持放电等物理过程。利用非链式脉冲DF激光器样机对模拟结果进行了相应的实验验证,测量得到的主、预放电电压波形与修正后的模拟电压波形一致。进而运用该模型研究了主储能电容、延迟电感、锐化电容对放电特性的影响,得到了有助于提高DF激光器放电性能的电路参数。 In order to improve the injection energy and discharge stability of non-chained pulsed DF laser, the circuit characteristics of sparkless needle pre-ionization discharge induced by unidirectional pulsed DF laser were studied. By analyzing the collision and dissociation of SF6 molecules in the working gas and its adsorption process to the electrons, the electronic continuity equation was obtained. Based on the Kirchhoff equation of the discharge circuit, a mathematical model describing the discharge characteristics of the DF laser was established. The model was used to simulate the relationship between the pre-ionization discharge voltage, the main discharge voltage and the current over time. The simulation results more accurately reflect the time delay between the pre-ionization discharge and the main discharge, the breakdown between the main electrodes and the self-sustaining discharge Physical process. The simulation results are validated by unchained pulsed DF laser prototype. The measured main and pre-discharge voltage waveforms are consistent with the corrected analog voltage waveforms. Then, the influence of the main storage capacitor, delay inductor and sharpening capacitor on the discharge characteristics was studied by using this model, and the circuit parameters that helped to improve the discharge performance of the DF laser were obtained.