Studies of online monitoring of the pressure in vacuum circuit breaker by Penning discharge

In this paper, a method based on Penning discharge is presented for online monitoring of the pressure in vacuum circuit breaker. By making some changes to the end exhaust pipe in the stationary conducting bar of vacuum tube, an inverted magnetron gauge can be formed. In order to perform a reliable discharge in this inverted magnetron gauge and not have any adverse influence on the operation of vacuum circuit breaker, the problems studied here include the relationship between reliable discharge and the size of discharge volume, and the features of Penning discharge in pulsed operation mode. A battery-powered step-up pulsed voltage circuit and a permanent magnet provide the electromagnetic conditions required by the discharge. An embedded CPU in the circuit controls the generation of pulsed high voltage, the measurement of the ion current and data communication with other devices by radio or by optical fiber. It can not only indicate the vacuity in vacuum tubes, but give the remaining safety margin of vacuum in them. The whole circuit is characteristic of low-power consumption and has an operating life of almost 10 years.