In order to make suggestions on the selection of starting resistance and the starting strategy of in the Kunliulong transmission project. This paper first introduces the start-up circuit of the flexible converter station. Then the startup loops under different topologies are analyzed，and the startup characteristics under different topologies are obtained. Finally，for the flexible converter station in Kunliulong transmission project，a PSCAD/EMTDC model is built to simulate the impact energy，and the results obtained are consistent with theoretical calculations. According to the simulation results，the requirements for the starting resistance shock absorption energy of the flexible converter station in Kunliulong transmission project and the system starting suggestions are proposed.