Electromagnetic Properties Research Of Permanent Magnet Actuator For 10kV Vacuum Circuit Breaker

The vacuum circuit breaker with permanent magnet actuator (PMA) has high reliability and good controllability, which is an ideal choice for synchronous opening and closing technology. To deeply study its design method and control techniques will help improve its static and dynamic performance, which has important implications for smart grid construction. This thesis designs three kinds of permanent magnet actuators for lOkV vacuum circuit breaker, including bistable, U-monostable and T-monostable ones. Their advantages and disadvantages are indicated by analyzing and comparing their characteristics with each other. After manufacturing and testing those prototypes, the experiment and simulation results are compared, which demonstrates the correctness and effectiveness the proposed design method.Firstly, the topological structure and working principle of the three PMAs are analyzed. By taking bistable PMA as an example, the design method is briefly introduced, which provides the preliminary design of those actuators including structure dimensions and coil parameters.Then, according to the preliminary design, electromagnetic field simulation models for the PMAs are established by using finite element analysis software Ansoft Maxwell. The simulation results including static and transient characteristics are given hereafter. For a permanent magnet actuator having preliminary structure dimensions, a bistable one for instance, this thesis proposes two methods including changing coil wire and reverse charging closing coil to improve opening speed of vacuum circuit breaker.For the purpose of simplifying design process and improving design efficiency, this thesis developes a Visual C++ based parameter creation software by calling PLOYFIT function in MATLAB. It can automatically create counter force function and coil parameters, which can be executed by Ansoft Maxwell, and read simulation results as well.Finally, the experimental platforms for bistable and U-monostable prototypes are built, combined with a lOkV vacuum circuit breaker, intelligent controllers, a switch mechanical properties tester and other equipments. The experiment and simulation results are in good agreement, which verifies the correctness of theoretical analysis.