Calculation of Reaction Force for the Gas-Blast Type Circuit Breaker

In order to explore the calculation method of the arc chamber gas reaction force and provide support for the design of the high-voltage circuit breaker mechanical transmission system, four calculation formulas of the reaction force micro-element under the four gas-solid interface conditions were derived, a test calculation case was designed and the effectiveness of the calculation method was verified. The no-arc simulation calculation model of the 252kV SF6 arc chamber was established, and the pressure distribution and the gas reaction force were obtained, the simulation results showed that: with the piston moving, the pressure inside the compression chamber increased first and then decreased, the max pressure of 1.86 MPa occurred at 0.029s; similarly, the reaction force changed with the same trend, the max reaction force of 1.95×104N occurred at 0.03s, which showed that under no-arc condition, the pressure load of the compressor chamber dominates the reaction force for arc chamber.