Fault current limiter is one of the effective means to solve the problem of excessive short-circuit current. Aiming at the governance requirements of excessive short-circuit current in 750 kV power grid, the topology and structure of 750 kV platform-type fault current limiter were studied. The design of power supply system, repulsion mechanism, platform insulation were carried out. And the power supply system and insulation performance of the whole machine were verified, as well as the switch characteristics. The whole machine adopts modular design, the failure of a single current-limiting unit will not lead to failure of the whole current-limiting unit. The bus voltage is borne by the supporting insulator, and a single current-limiting unit only needs to be designed according to the insulation level of 72.5 kV. Inverted CVT power supply, dual power supply redundancy, power supply protection logic, and continuous power supply for 10s after power failure can ensure the reliability of platform power supply. The opening time of the fast switch driven by the repulsion mechanism is 0.616ms, and the closing time is 26.4 ms. The maximum field strength of the platform is 2 kV/mm, and the insulation meets the requirements. The fault current limiter designed can meet the requirements of engineering applications.