一种电容补偿型高压电容分压器的设计

根据高压脉冲实验测量的需要,阐述了外带积分器型、电阻补偿型及电容补偿型等几种电容分压器的工作原理,分析了影响各自响应时间的主要因素即对于测量ns量级快前沿高压脉冲信号,使用外带积分器型电容分压器时不宜采用大尺寸的伞式探针结构;使用电阻补偿型电容分压器时对其高压臂大电阻要求较高。在缺少高性能大阻值电阻的情况下,利用高压电容尝试设计并制作了电容补偿型电容分压器,其分压比约为9348,它在一定范围内可通过改变补偿电容值而方便地改变。实验结果与理论计算及PSpice软件的模拟结果基本一致,方波响应时间约为4.4ns,基本达到了设计目的。定标结果表明该分压器可用于测量高功率脉冲调制系统和强流电子束加速器中的高压脉冲。

Design of Capacitance-compensated Capacitive Divider for High-voltage Pulse Measurement

This article presents the principle of several kinds of capacitive dividers,which are capacitive dividers with integrators,resistance-compensated capacitive dividers and capacitance-compensated capacitive dividers.Expression of square wave response is deduced using the Laplace transformation to analyze factors effecting the response time of the capacitive dividers with integrators.By analyzing the other two kinds of capacitive dividers,it is found,when high voltage pulse signal with a steep front of ns range is measured, if capacitive dividers with integrators are applied,it is not suitable to choose umbrella probe of large scale,because if the capacitance of the low voltage arm is excessively large,it results in long response time,while other structure for this kind of measuring may be more complicated;If resistance compensated capacitive dividers are applied,high performance resistors of high resistance are required,as the second stage resistive dividers are essentially high resistance dividers.Due to the lack of high performance resistors,a capacitance-compensated capacitive divider is designed utilizing high voltage capacitors for measuring high voltage pulse with considerably long pulse width,steep front and amplitude up to several hundred kilovolts.Experimental results agree well with theoretical computation and simulation results from the PSpice software.The response time is about 4.4 ns.The ratio is about 9348,and can be changed in a certain range by altering the compensated capacitance.The calibrating results indicate the divider is feasible to measure the high voltage pulses on high power pulse modulators and intensive electric beam accelerators.