A New Type Electromagnetic Repulsive Mechanism for 40.5 kV Vacuum Circuit Breaker

In this paper, based on the research of "coil-coil" type electromagnetic repulsive mechanism, a new electromagnetic repulsive mechanism is proposed. The new mechanism improves the magnetic circuit that generates a magnetic field in a fixed coil, and the moving coil can be subjected to downward or upward electromagnetic force in the magnetic field , and driving the guide rod to move. In the process of motion, with the movement of the moving coil, the air gap of the magnetic circuit can be kept unchanged, and the magnetic resistance is only slightly increased, so the new mechanism has a longer stroke. The mathematical model of the magnetic field of the mechanical magnetic circuit is established, and the expressions of the air gap magnetic field strength and electromagnetic force are obtained. Based on the finite element analysis software, the new mechanism is simulated and analyzed, and some factors affecting the opening time of the mechanism are obtained. The parameters of the repulsive mechanism are optimized and analyzed. The simulation results show that the proposed electromagnetic repulsion mechanism has a faster opening speed and a long stroke.