To address the issue of DC voltage rise in large-scale wind power DC transmission systems based on modular multilevel converters （MMC） during AC voltage dips at the receiving end, a fault ride-through strategy utilizing supercapacitor energy storage MMC is proposed. The strategy involves utilizing the supercapacitor energy storage system to absorb surplus power during faults, thereby stabilizing the DC bus voltage, while optimizing the active and reactive current distribution of the receiving-end MMC to prioritize reactive power support for the AC grid. After the fault, the stored energy in the supercapacitor is released back into the grid, improving the utilization efficiency of wind power. Additionally, a parameter design method is presented for the supercapacitor energy storage system, including the filter inductance of the bidirectional Buck/Boost converter, the series and parallel numbers of supercapacitors, and the voltage reference value during steady-state operation. Simulation results in PSCAD/EMTDC demonstrate that the proposed strategy effectively suppresses overvoltage on the DC side and enhances the system's fault ride-through capability. In addition, the simulation results also verify that the proposed scheme has advantages in terms of DC voltage stability and energy utilization efficiency compared with the fault ride-through strategy based on DC unloading circuit.