脉冲功率装置中电容分压器的设计和应用

为了测量脉冲功率装置形成线和传输线的电压,设计和标定了自积分电容分压器和V-dot探测器。在电容分压器结构设计中,重点叙述了降低结构电感、削弱局部高电场以及保持灵敏度一致的方法。电容分压器采用在线标定,标定用电阻分压器安装在电容分压器相对于轴线对称的位置,以减小对探头位置电场分布的影响。对阳加速器水传输线、脉冲形成线和PTS单路样机中储探测器的标定和实验结果表明:无论是自积分电容分压器还是V-dot探测器,只要取值合适,同时在结构设计中注意分布参数的控制,就都可以响应前沿为几十ns至接近μs量级的信号。

Design and Performance of Capacitive Divider for High-voltage Pulse Measurement

Several capacitive dividers and V-dot monitors were designed to measure high-voltage pulse.The monitors were installed on water transmission line and pulse forming line.The capacitor from cathode to the probe was the high-voltage arm of divider,which could reduce the structural inductance when the low-voltage arm of the capacitive divider was a ceramic capacitor ring and the structure was designed as coaxial.The V-dot monitor was another capacitive divider without the low-voltage arm.The output of V-dot was proportional to the time derivative of the voltage.And the signal proportional to voltage was given by a RC integrator.It could impair electric field intensity in water-plastic-metal triple-point when the surface of probe's insulation was lower than the probe.The position of probe compared to the inner-surface of anode could be immovable when pressurized ring was put in the groove.It could hold the sensitive of monitor changeless even if the probe was installed again.The monitor was calibrated in site with a calibrated resistive divider.The resistive divider was fixed to another side of coaxial line to reduce the change of electric field about the monitor.All monitors worked well at the highest Marx bank charge voltages.The capacitive divider and the V-dot monitor could response the signal of which raise time was from several decade nanoseconds to near microseconds when designed value and the distributed parameter of structure were proper.