67 / 2021-06-04 09:23:11

Study of Laser-Induced-Plasma in Vacuum Breaker

Vacuum breaker has many advantages, such as low failure rate, compact structure, no greenhouse gas emission, and strong breaking capacity. Therefore, it’s widely used in medium and high-voltage power systems. The vacuum interrupter as the core component of the vacuum breaker, it’s vacuum degree directly determines whether the circuit can be broken reliably. However, the online monitoring of the vacuum degree of the vacuum breaker has always been a worldwide problem. In the previous work, our research group proposed to characterize the vacuum degree of the vacuum breaker by the radiation intensity and topographic characteristics of the laser-induced plasma. In this work, a vacuum breaker is simulated by a vacuum chamber and a shield of vacuum breaker, and the influence of the delay time and laser energy on the laser plasma at different pressures is studied by plasma imaging from the direction of laser incidence. The experimental results show that the laser plasma radiation intensity decreases with the increase of the ICCD’s response delay time, increases with the increase of the laser energy, and increases with the decrease of the pressure. This work verifies the feasibility of the vacuum detection of vacuum breaker based on laser-induced plasma imaging, and can lay the foundation for the practical application of vacuum degree detection based on laser-induced plasma.