Investigation on phasing controlled vacuum circuit breaker for switching overvoltage of 110kV power system

Based on a special angle of voltage or current of power system, controlled switching technology of vacuum circuit breaker is presented to decrease overvoltage and inrush current due to the power equipment operating such as transmission line closing and no-load transformer closing. The optimum switching instant and synchronous switching control strategies are given by synthetically considering closing action time dispersion and pre-strike characteristic of vacuum circuit breaker. The optimal target points of the controlled switching technology are deduced and calculated by Matlab. The switching over voltages are simulated by statistical in ATPdraw. Simulation results show that the closing voltage of transmission can be reduced to 2.35 p.u. and switching voltage of transformer can be reduced to 1.85 p.u. So the theoretical analysis and synchronous switching control strategies in the article are verified correctly.