Research on the Magnetic Repulsion Composite Operating Mechanism for Long-Stroke High-Voltage Circuit Breakers

To address the high-speed tripping requirements of large-capacity, long-stroke high-voltage circuit breakers, this paper proposes a novel composite mechanism that combines magnetic and repulsive forces. A timing circuit is used to control the engagement time of the repulsive mechanism, allowing the electromagnetic force to increase rapidly, thus accelerating the mechanism's action and optimizing the circuit breaker's interruption capability. Finite element methods were employed to simulate and analyse the motion characteristics of the magnetic-repulsive composite mechanism. The study primarily investigates the impact of the composite mechanism on the tripping process compared to the magnetic mechanism, as well as the effect of the timing of the repulsive mechanism's intervention on the motion characteristics of the mechanism. The simulation results indicate that, compared to the magnetic mechanism, the composite mechanism significantly enhances the tripping speed and reduces the tripping time. Furthermore, the intervention of the repulsive mechanism at the initial action of the magnetic mechanism yields the best motion performance. This research provides valuable insights for the design of operating mechanisms in large-capacity, long-stroke high-voltage circuit breakers.