Study Of Operating Mechanism In High-performance MCCB With ADAMS

Molded case circuit breaker(MCCB) is the core component in low-voltage apparatus. In recent years intelligence and high performance of MCCB are developed. Shorter operation time are needed to improve interruption ability of MCCB, which means the operation mechanism should have higher operating characteristics.In this study operating principle and design parameters are analyzed. By introducing analysis of transmission ratio and equivalent dynamic model, operating velocity and close process of sensitive parts are analyzed and torque calculation is matched. According to characteristics of the operating force, differences of simulation in closing, opening and resetting operations are represented. And a simulation model of resetting force is established. By combining design experience of operating mechanism, classical operating mechanism transforming from four bar to five bars is established. The corresponding simulation model is calculated by using dynamic multi-body software ADAMS, by which the translation, velocity, acceleration and animation video of each part in simulation model can be measured. Driving and resisting moments are achieved by evaluating dynamic parameters and analyzing force distribution of the mechanism. Designing demand of resetting force is satisfied by the use of virtual model. By analyzing influence of main spring and bar size to opening velocity, optimizing works are done. Based on the simulation results, the type model of MCCB is finished. The interrupting ability, electric life and other performance of the type model verify the validity of simulation model.From the experiment results each performance index of operating mechanism can satisfy design demands of high performance of MCCB.