基于Kerr电光效应，建立了用以对纳秒脉冲高电压作用下的真空绝缘子表面电场进行在线测量的实验系统。该测量系统由快脉冲高电压源、YAG激光器、同步控制系统、被测中空薄壁绝缘子及Kerr效应单元、光学相位差检测系统等部分构成。利用YAG激光器输出的激光脉冲，触发导通快脉冲高压源中的高压气体开关，使其给被测绝缘子试品上施加一个脉宽100 ns的高压脉冲方波。利用同步控制，使得探测激光在试品上的脉冲方波达到幅值后，入射到Kerr腔体中对Kerr效应进行探测。从而实现了对绝缘子表面电场的在线测量，并给出了初步的测量结果。

An on-line measurement system based on Kerr effect is established to investigate the surface electric field of insulators stressed by nanosecond high-voltage (HV) pulse in vacuum. A 180 kV Marx generator with the high-voltage cable as the pulse forming line are utilized to output a square nanosecond HV pulse stressing on insulator specimen in Kerr cell, once a gas switch is conducted by a laser pulse emitted from a YAG laser. And a synchronous controlling apparatus is developed to make sure that the measurement on surface electric field is performed during the HV pulse being stressing on the insulator. Accordingly, a preliminary experimental observation on surface electric field is performed.