在聚龙一号装置(PTS装置)上开展了系列波形调节实验,成功在负载上输出脉冲上升时间达到600 ns、峰值电流大于5.0 MA的电流。聚龙一号装置在同步放电情况(短脉冲模式)下,负载电流的上升时间约90 ns, 峰值电流约10.0 MA。波形调节通过装置24台激光触发气体开关分时放电、脉冲输出开关短接等技术调整,实现负载上长上升时间的脉冲电流输出。波形调节根据需要实现的电流波形形状,通过全电路模拟计算,调整激光触发气体开关的触发时序和脉冲输出开关状态,在相应负载上输出接近需求的实验波形。聚龙一号装置波形调节实验研究表明,输出电流脉冲的前沿的最大值取决于24台激光触发气体开关最早触发时刻和最晚触发时刻的时间差,该时间差受制于激光触发气体开关的正常触发。激光触发气体开关能否被正常触发,除了取决于进入开关触发间隙的触发激光能量外,还取决于开关充气压力和加载于开关两端的电位差,该电位差与相关两路的渡越时间相关。通过波形调节研究,聚龙一号装置具备在不同实验负载上输出不同上升时间、不同波形形状的脉冲电流的能力。

A series of current pulse shaping experiments have been carried out on the Primary Test Stand(PTS). More than 5 MA peak current were successfully achieved on the load with a rise time of 600 ns. The typical rise time of PTS machine is 90 ns with about 10 MA peak current under short pulse mode, which means all 24 modules discharged simultaneously. By distributing the laser trigger target time of 12 laser beams logically and adjusting the status of the pulse output switch, longer rise time pulse can be obtained on the PTS facility. According to the required pulse shaping, whole circuit simulation will be used to calculate the trigger time of each laser triggered gas switch and the status of the pulse output switches. The experimental results indicate that the rise time of the current is determined by the time difference between the first and last triggered gas switches, normally it should be less than the transition time of the two neighboring modules. In order to trigger the laser triggered gas switch, sufficient laser power is needed to be sent into the gap of the gas switch, the gas switch press and voltage difference on the two electrodes also affects the triggering of the gas switch. The voltage difference is determined by the switch’s transition time. The study and experiments of the pulse shaping on PTS show the adaptable ability of the PTS for offering different waveform of mega ampere current pulse for different research purpose.