Design of Main and Auxiliary Gap Linkage Mechanism and Self-Driven Mechanism of High Voltage Vacuum Interrupter

Vacuum circuit breaker is one of the mainstream directions to realize the environmental protection replacement of SF6 in high voltage power switch. However, there is a bottleneck of long gap insulation saturation in vacuum interrupter, which limits its development to higher voltage level. In this paper, a vacuum interrupter structure with integrated auxiliary gap and main gap is proposed, which is expected to achieve a breakthrough in the voltage level of 252 kV and above. Firstly, a new structure of high voltage vacuum interrupter with main and auxiliary gaps in series is designed, and the principle of asynchronous linkage between main and auxiliary gaps is analyzed. Secondly, a multi-dimensional coupling simulation method of transient electromagnetic field and multi-body dynamics which can fully reflect the dynamic characteristics of main and auxiliary gaps is proposed. Finally, the influence of relevant parameters of self-driven mechanism on the opening motion and collision characteristics of arc extinguishing unit is simulated and analyzed, and the selection design is carried out. The simulation results show that the opening displacement of the designed self-driving mechanism can reach 22.5 mm in 20 ms, and the peak value of the collision impact force is 42668 N when the opening is in place, which is 66.5%lower than that of the unconfigured eddy current damping. This paper provides a new idea for the development of 252 kV vacuum interrupter, and provides theoretical guidance for the design of mechanical linkage switch.