Research On Motor Operating Mechanism In High Voltage Circuit Breaker

With the development of power electronics technology,intelligent electrical appliances have attracted the attention of scholars.The motor operating mechanism of high voltage circuit breaker is a new type of the operating mechanism witch can match modern power electronics technology to improve the reliability and intelligence of the circuit breaker.This paper has designed the driving motor which is used in the 40.5kV vacuum circuit breaker operating mechanism,and taken driving motor as the research object,the control strategy is researched.Firstly,the structure and principle of Permanent magnet brushless DC motor(BLDCM)are introduced;the dynamic model of the motor is established,the controllability of permanent magnet brushless DC motor is studied;the motion characteristics of the vacuum high voltage circuit breaker;and the influence of high voltage circuit breaker contact switching speed on the performance of the circuit breaker are analyzed;the ideal speed curve of the drive motor during the closing process of the circuit breaker is proposed.A motor design method which takes the energy required by the maximum torque as the target parameter is proposed according to above analysis.The BLDCM is designed by combining electromagnetic field calculation and magnetic circuit calculation.The motor rotor structure is simulated and analyzed by ANSNS/Maxwell software,and the dovetail groove pressing type of rotor is determined.The design method of the motor winding of the motor winding is selected by changing the turn diameter ratio of the motor winding under the condition of the full rate of the motor slots and the number of ampere turns of the motor.Then,according to the permanent magnet brushless drive motor,the control strategy of the motor operating mechanism is studied,and the PID control method based on radial basis radial basis function neural network(RBF-PID)of motor motion process is proposed.The MATLAB dynamic simulation model of BLDCM is established,the conventional double closed loop control system is designed,the PID parameters are adjusted.While the results show that the conventional PID control system can't achieve a good tracking function in the whole speed adjustment process.A PID control method based on radial basis radial basis function neural network is proposed to improve the control effect of PID method in this paper.Both of the control systems are simulated and compared,the results show that the RBF-PID control system tracks the given speed curve well,and realizes better control effect on the driving motor's movement process.At the end of this paper,the test of motor operation mechanism of 40.5kV high voltage circuit breaker is carried out.The control platform of the driving motor is built.The motor control test,interval debugging test and intelligent control test is done.The test results show that the driving motor is reasonable and reliable,and the designed control method and control system are feasible.