In order to limit the 90 kA-level short-circuit current of power grids where the voltage class is equal to or greater than 500 kV

a current limiter topology based on high coupling split reactor is proposed. The inductance of one arm of the high coupling split reactor is in series with a group of quick switches

and the inductance of the other arm is in parallel. The input of the current limiter is controlled by quick switches. Firstly

the topology structure and working principle are analyzed and improved in detail

and the validity of the topology principle is verified by small prototype tests. Then

a equivalent model of the 500 kV system on the basis of the actual power grid parameters is set up. Through the configuration principle of current limiter parameters

the parameters of current limiter of 500 kV-90 kA-level short-circuit current are determined. The simulation results show that this topology has a current limiting depth of over 40% for the 90 kA short-circuit current

and the over-voltage in the limiting process will not exceed. Finally

in order to reduce the influence of current limiter on the main circuit breaker

the 1 500 n F capacitance is in parallel at both ends of the single module of the current limiter. The selection principle of the parallel capacitance of 500 kV system is given. And it is verified that the parallel capacitance will not impair the internal insulation of the current limiter.