A Novel Repulsion Hydraulic Operating Mechanism for Fast High Voltage Circuit Breaker

As the scale and complexity of the grid continues to escalate, the short-circuit current level of the power system keep increasing. Fast circuit breaker can effectively reduce the impact of short-circuit current and become one of the research hotspots of high-voltage circuit breaker (HVCB). The novel repulsive hydraulic operating mechanism proposed in this paper takes the comprehensive advantages of the fast response characteristic of repulsion mechanism and the characteristic of large output in the large stroke range of the hydraulic mechanism, which can help to achieve rapid opening of HVCB. The working principle and technical route of the proposed repulsive hydraulic operating mechanism are expounded. And the research on repulsion device and hydraulic system is conducted respectively from functional requirement, system modeling and parameter optimization. On the basis of which, the prototype of 252kV circuit breaker driven by the novel repulsion hydraulic mechanism is built to verify the correctness of the design and optimization method for the novel operating mechanism, and the feasibility of the novel repulsion hydraulic mechanism used to drive HVCB to achieve rapid opening. The tests show that the 252kV fast circuit breaker can complete arc extinguishing within 25ms, which is about forty percent less than conventional circuit breakers.