强激光与粒子束, 2011, 23 (7): 1985, 网络出版: 2011-07-29
PW级Z箍缩驱动源指数传输线的电路模拟
Circuit simulation of exponential transmission line for petawatt Z-pinch plasma drivers
电路模拟 指数传输线 脉冲传输 传输效率 Z箍缩等离子体驱动源 circuit simulation exponential transmission line pulse transmission transmission efficiency Z-pinch plasma driver
摘要
采用PSPICE软件,以PW级Z箍缩驱动源指数传输线为例,模拟分析了用有限多段分段阶跃变阻抗传输线序列模拟连续指数变阻抗传输线时,直角波、半周期正弦、全周期正弦平方等入射脉冲的电压和功率传输效率与分段数以及脉冲参数的关系,并计算了水电阻率对功率传输效率的影响。模拟结果表明:直角波波头的电压和功率传输效率随分段数增大而迅速趋近于理想传输线变压器的值;但对于非直角波入射脉冲而言,分段数并非越多越好,而是存在一个与传输线电长度和输入脉冲波前时间相应的最佳值;随着水电阻率下降,功率传输效率加速降低。
Abstract
It was demonstrated, based on the PSPICE circuit simulation, that the sectioning number for the circuit simulation of an exponential transmission line should be determined as twice the line’s one-way electromagnetic wave transport time (electric length) divided by the wave-front of input pulse, owing to elimination of the wave reflections caused by artificial impedance discontinuity in the line’s circuit simulation model, which employs a serial and sectional transmission line with impedances constant in each section but stair-step-varied between sections, and with total electric length the same as that of the exponential line under simulation. A pulse of 112.2 ns wave-front propagates through an exponential water transmission line of 1 234.2 ns one-way transport time will give the best sectioning number of 22, when the constant impedance of each section is given by the geometric mean of the two ends’ impedances of the corresponding section on the exponential line under simulation. This sectioning rule is equivalent to the statement that the two-way transport time of each section should be equal to the input pulse’s wave-front.
曾正中. PW级Z箍缩驱动源指数传输线的电路模拟[J]. 强激光与粒子束, 2011, 23(7): 1985. Zeng Zhengzhong. Circuit simulation of exponential transmission line for petawatt Z-pinch plasma drivers[J]. High Power Laser and Particle Beams, 2011, 23(7): 1985.