There are three types of vacuum circuit breaker operating mechanism: electromagnetic actuator, spring actuator and permanent magnet actuator.
Electromagnetic actuator consists of a solenoid coil and core, with the opening spring and the necessary mechanical locking system components, simple structure, fewer parts, reliable, low manufacturing costs. At the same time solenoid solenoid output characteristics easily meet the vacuum circuit breaker closing reaction characteristics requirements. The disadvantage is that the closing coil power consumption is too large, requiring the allocation of expensive batteries, coupled with the structure of the electromagnetic body bulky, longer operating time. Electromagnetic actuator appeared first, but the current amount tends to decrease.
The spring-operated mechanism stores all the energy required for closing and closing by a spring, and drives the vacuum interrupter contact action through the cam mechanism and the four-bar linkage mechanism. Its sub-closing speed from the power supply voltage fluctuations, rather stable, by adjusting the spring pressure to meet the requirements of sub-closing speed. The disadvantage is the mechanical parts (up to more than 160), parts of the material, machining accuracy and assembly accuracy have a direct impact on the reliability of institutions. The output characteristic of the spring mechanism is basically the energy release characteristic of the energy storage spring. In order to improve the matching, the four-bar linkage and the cam mechanism are used in the design to change the characteristics. At present, the spring operating mechanism technology has matured, so a larger amount.
Permanent magnet mechanism is a new operating mechanism, which uses permanent magnet, electronic control, capacitor storage. Its advantage is the simple structure, the number of parts is small, the work of the main moving parts only one, without mechanical tripping, locking device. Permanent magnet mechanism is divided into two types: monostable permanent magnet mechanism and bistable permanent magnet mechanism. Permanent magnet mechanism still need to stand the test, need to solve the problem of capacitor life, permanent magnet retention and reliability of electronic devices and other issues. At present, the amount is not large.
Article from NdFeB Industry Network