Analysis And Automatic Design Study Of Circuit Breaker Spring Operating Mechanism

The spring operating mechanism of circuit breaker is widely used in daily life as a kind of switching equipment.It plays the role of protecting and controlling the power network by connecting or cutting off the circuit.Spring operating mechanism is types of actuator commonly used in circuit breaker.The breaker is mainly operated by the spring actuator to complete the closing.But the output force characteristics of the spring operating mechanism can’t match well with the load characteristics of the circuit breaker.At the same time,according to the statistical data,the operating mechanism fault occupies a high proportion in the circuit breaker failure.Therefore,in order to better match the output and load of the circuit breaker and reduce the failure rate,it is particularly important for the rational design of the spring operating mechanism.In the design process of the spring operating mechanism of the circuit breaker,the traditional design methods mostly depend on the design experience accumulated by the designer in the engineering practice or refer to the imported foreign products for reform and design.It is of great significance to find a more systematic,simple and intuitive design method for the spring actuator of circuit breakers.In the spring operating mechanisms of the circuit breaker,the force released by the closing spring determines the output force of the system’s closing process and affects the life of the system.Therefore,the parameters of the split spring need to be reasonably designed and selected.According to the relationship between the output requirements of the circuit breaker and the spring characteristics,the spring parameters are designed and calculated according to the spring design standard.In the circuit breaker spring operating mechanism,the use of cam makes the input and output of the operating mechanism better match.It is very important to design the cam profile curve simply and accurately.Through the analysis of the relationship between the cam parameters and the output force characteristics and the design method of the oscillating roller follower cam,the mathematical model of the cam mechanism in the spring operating mechanism is set up,and the genetic algorithm is used to solve the mathematical model.A graphical user interface(GUI)is developed based on MATLAB.The structural parameters of the double four-bar linkage in the spring operating mechanism of the circuit breaker directly affect the speed and displacement of the moving contacts of the circuit breaker.In order to meet the output requirements of different circuit breakers,the structure of the double four-bar linkage is different in different spring operating mechanisms.In order to adapt to the output requirements of different organizations in the actual production process,the theoretical modification scheme of the parameters of thedouble four-bar linkage is quickly and accurately given.By analyzing the relationship between the hinge four-bar linkage and the output characteristics of the spring operating mechanism of the circuit breaker,the structure parameters of the hinge four-bar linkage are designed according to the output force characteristics,and the optimization results are calculated based on the particle swarm optimization algorithm.The test platform is set up to test the gate speed and rebound amplitude.Based on the development of the graphical user interface(GUI),the optimization results can be obtained by changing the corresponding parameters,so that the four-bar linkage of the spring actuator can be designed intuitively and conveniently.In this paper,the graphical user interface is programmed by Visual Basic 6 language,and the automatic design of circuit breaker spring operating mechanism is studied.The automatic design method makes the spring operation mechanism more intuitive and convenient,and shortens the design cycle.