Vacuum Detection Equipment of Vacuum Switch Based on Laser-Induced Plasma Imaging

Vacuum switch is used in power system because of its compact structure and strong breaking ability. The vacuum degree of vacuum switch directly determines the breaking performance of vacuum switch, but the existing technology can't achieve reliable on-line monitoring of vacuum degree. In this paper, a vacuum detection equipment of vacuum circuit breaker based on laser-induced plasma optical multiplexing was developed, which is expected to realize the vacuum on-line monitoring of the vacuum switch, and the experiment of vacuum detection was carried out at 10–⁴ Pa ~ 1 Pa. The experimental results show that the smallest detection error of this equipment is only 13.3% ± 4.8% when the reference vacuum is 1 Pa, which is better than the hot-cathode ionization gauge used in this experiment. When the reference vacuum is 10–³ Pa, 10–² Pa, and 10^–1 Pa the detection accuracy of this equipment is comparable to that of the hot-cathode ionization gauge used in this experiment. When the reference vacuum is 10–⁴ Pa, the detection error is the largest. This work can lay a foundation for the practical application of vacuum detection method of vacuum switch based on laser-induced plasma.