Research On Dynamic Simulation And Stress Analysis Of Spring Operating Mechanism Of High-voltage Circuit Breaker

High voltage circuit breaker is an important device for protecting and controlling the electrical circuits in high voltage electrical equipments.A large number of circuit breaker accident investigation statistics show that operating mechanism fault is the main cause of circuit breaker failure.The operation reliability of the circuit breaker is not only related to the electrical performance(such as the breaking and insulating property),but also largely depends on the mechanical reliability of the operating mechanism,such as dynamic characteristics and mechanical strength,etc.In order to improve the mechanical reliability of the circuit breaker,the dynamic characteristics and stress distribution of the circuit breaker operating mechanism need to be analyzed and studied in depth.In this paper,the 3D-model of operating mechanism is established by Pro/E firstly,then the dynamic simulation analysis about the length,velocity and other characteristics of the moving contact in the breaking and closing course is carried out,the model is verified by contrasting the experimental data.The finite element modeling and solving analysis of the mechanism are carried out by Hyper Mesh and LS-DYNA.The simulation results obtained the stress distribution of the critical components and pointed out the dangerous parts which need to be noticed.Finally,the stress acquisition test of the critical components is carried out by the strain gage embedment method.By comparing the simulation results with the experimental results,it can be concluded that manufacture errors,installation errors,service wear,impact damage and other factors in the operating mechanism may have a significant impact on the dynamic characteristics and stress distribution of the mechanism.Cam roller mechanism has a large impact force;the crank arm,transmission rod and the spring have the stress concentration;the long rod parts also have the problem of vibration and instability.The analysis methods and results can provide theoretical guidance and reference for the research and optimization design of the circuit breaker operating mechanism and improve the analysis efficiency.