气体火花开关放电通道半径及电阻测量

搭建低电感实验回路平台，利用高速分幅相机拍摄火花开关放电通道发展过程，分析照片光强和放电通道半径的对应关系，根据图片光强测定不同时刻放电通道的半径，提出适合实验条件的放电通道半径计算公式。依据高压探头和Pearson线圈测量得到的放电通道电压和电流波形，计算放电通道的电阻，再利用测量的放电通道半径进而得到其电导率。放电通道半径随着放电通道的发展逐渐增大，有饱和的趋势，放电电流2 kA时电流峰值处放电通道半径约0.6 mm；随着放电电流峰值的增大，放电通道电阻下降速率增大，达到稳定值所需的时间减小，稳定值也随之减小，其电阻稳定值最小能达到0.08 。

Arc radius and resistance measurement of spark gap switch

With a low-inductance experimental apparatus， the arc radius is obtained by photographing the discharge processes of the spark gap switch with high-speed framing camera， and a formula is proposed for calculating the arc radius. The time-dependent arc resistance and conductivity of spark switch gap in the low-inductance circuit are obtained by solving the circuit equation using measured values of current and voltage. The arc radius increases and gradually reaches a saturation value while the discharge channel develops. The radius is 0.6 mm at the peak discharge current of 2.8 kA. The saturation resistance and the time to reach saturation decrease with increasing the peak current of discharge. In addition， the saturation value of arc resistance can be minimized to 0.08 .