Dynamic Characteristic Simulation And Research On 27.5kV Permanent Magnet Actuator For Vacuum Circuit Breaker

With the rapidly development of electrical railway and the raised speed of electric engine, it requires more and more higher quality and reliability of railway power supply system. As a controlling and protecting equipment of vacuum circuit breaker, the reliability of opening and closing operation has great influence on power supply system. The key factor affects vacuum circuit breaker reliability is the operation of the actuator's reliability. As a kind of new vacuum circuit breaker, the new operating principle is adopted by Permanent Magnetic Actuator (PMA), in which, the electromagnetism actuator and Permanent Magnet (PM) are rationally combined, The mechanical tripping and locking devices of conventional actuator have been eliminated; the main moving part remains one, So the PMA parts are decreased by 50% comparison with conventional spring actuator. Structure and the parts have been largely simplified; the reliability of mechanical system has been greatly increased. Thus, to develop 27.5kV vacuum circuit breaker with permanent magnetic actuator becomes more significant.27.5kV vacuum circuit breaker with PMA has longer separation and needs faster opening and closing speed, it's more difficult to develop. So to research the dynamic characteristic becomes more meaningful for improving the performance of vacuum circuit breaker. In this work, the static characteristics of the permanent magnetic actuator are obtained using the finite element model with use of Ansoft software package. Next, the electrical circuit and mechanical models which describe the behavior of the circuit breaker are constructed using MATLAB package. The dynamistic characteristics are simulated on the basis of over static simulation. And results for the time variations of the coil current, the displacement of the contact system, move velocity and electromagnetic force are obtained. Finally, the testing plant is designed and the experiment is conducted in order to evaluate veracity of the simulation, it is indicated that simulation results coincide well with the experiment.