The Research On Permanent Magnetic Linear Motor Actuator For High Voltage Circuit Breaker

Actuator is one of the most important components of the circuit breaker which must ensure the action reliability of circuit breakers in long-term operation and meet the requirements of the operating mechanism determined by the arc at the same time. Linear motor actuator of the high voltage circuit breaker has a good rapid response capability and maneuverability, it uses linear motor as the entire drive source, with the cooperation of the mechanism such as the connecting rod and so on, to drive the movements of the moving contact and achieve the separating and closing operation of the brake.In this paper a kind of permanent magnet linear motor is designed which meets the separating and closing operation properties of the high voltage circuit breaker. The research method used is based on the simulation and experimental results of the permanent magnet mechanism which proves the rationality of the design. Analysis results of linear motor actuator of the high voltage circuit breaker are gained by analyzing the force characteristic of the high voltage circuit breaker and simulation of the electric actuator designed with the finite-element analysis method.First, the load characteristics and quality of 40.5 kV vacuum circuit breaker are calculated. This could provide the foundation and basis analysis of the dynamic of actuator side. Experiments on the vacuum circuit breaker which is mounted with a permanent magnetic actuator in it are carried out. The open and close current over time, the displacement of actuator side over time, travel curve of contactor as well as the curve of capacitance-voltage are obtained by experiments. Thus provide a reliable experimental basis for comparative analysis of permanent magnet linear motor actuator.Secondly, the 40.5kV vacuum circuit breaker with permanent magnet linear motor actuator are designed. Through experiment Stroke curve of actuator, curve of driving force are obtained. The 40.5kV motor actuator of the linear motor is presented and its advantages and disadvantages compared with the permanent magnet actuator are found through its simulation. Meanwhile, the reasonableness of the design of the motor are verified; Finally, the load characteristics and quality of 126kV vacuum circuit breaker are calculated. Then, permanent magnet linear motor actuator which meets the performance parameters of the circuit breaker is designed. Through simulation, its rationality and engineering properties are proved by analyzing its dynamic electromagnetic force, velocity characteristics, displacement characteristics. This verified the requirements of circuit breaker closing characteristics could be meet.