三种CuCr触头材料对真空灭弧室投切背靠背电容器组性能的影响

为研究三种不同触头材料(真空熔渗CuCr50、真空熔铸CuCr40Te0.005、电弧熔炼CuCr50)对真空灭弧室投切背靠背电容器组性能的影响,将采用三种不同材料制备的触头各装配在三只相同的12kV等级真空灭弧室中,每只真空灭弧室经过80次背靠背电容器组合分操作,高频涌流设定为幅值8 kA、频率3.8 kHz。结果表明:真空熔渗CuCr50、真空熔铸CuCr40Te0.005以及电弧熔炼CuCr50的平均重击穿概率分别为6.7%、5.8%、8.3%,重击穿现象主要发生于恢复电压持续时间的1/4T与10T之间(T表示恢复电压周期20 ms);复燃现象多次出现,真空熔铸CuCr40Te0.005(1次)电弧熔炼CuCr50(9次)真空熔渗CuCr50(10次)。

Effects of Three CuCr Contact Materials on Properties of Back-to-back Capacitor Banks Switching Performance in Vacuum Interrupters

This paper investigates the performance of back-to-back capacitor bank switching in vacuum interrupters（VIs） with contacts prepared by three different technologies, including infiltration CuCr50, vacuum induction melting CuCr40Te0.005, and vacuum arc melting CuCr50. Each kind of contacts is installed in three 12 kV VIs and the VIs undergo 80 closing/opening operations of back-to-back capacitor bank switching tests at an inrush current of 8 kA （peak value, frequency 3.8 kHz）. Results show that the average values of the restrike probability of the VIs for each contact material are as following： the vacuum induction melting CuCr40Te0.005 is 5.8%; the infiltration CuCr50 is 6.7%; and the vacuum arc melting CuCr50 is 8.3%. For all VIs, the restrikes mainly occur between 1/4T and 10T of the recovery voltage（T, the cycle of the recovery voltage, is 20 ms）. Reignition also occurs before 1/4T, and the occurrence number as follows：vacuum induction melting CuCr40Te0.005（1 time）〈vacuum arc melting CuCr50（9 times）〈infiltration CuCr50（10 times）.