Abstract: This paper proposed a topology for integration of permanent magnet direct-driven wind turbines through a hybrid HVDC system. The HVDC system, adopting a modular multilevel converter（MMC） on the rectifier side and a line commutated converter（LCC） on the inverter side, combines the advantages of both MMC and LCC. MMC can transmit power from the passive networks of wind farms without an external commutation voltage; LCC can reduce the investment cost and power losses. By changing the number of the switched-on sub-modules, MMC can change its DC side voltage instantaneously. Based on this characteristic, this paper proposed a method to control the DC current of MMC, extending MMC control dimensions from AC side to DC side. The results of simulations show that MMC DC current control can reduce the possibility of LCC commutation failures and improve the power recovery performance after a commutation failure, achieving the goal of fault ride-through.