A major problem in the operation of HVDC infeeded to a weak AC system is that the faults occurred in the receiving AC system may cause commutation failures of the inverters, and in the event of faults removal, the receiving system will be further weakened, so that the AC/DC system will be difficult to restore to a stable operation state, and even may lead to DC system blocking. Based on electromagnetic transient simulations, this paper studies the characteristics of commutation failures of a DC transmission system infeeded to a weak AC system induced by AC faults near the inverter station, as well as the fault recovery characteristics of the AC/DC system with further weakened receiving systems. The HVDC transmission capability of the steady-state operation is evaluated by the dynamic process of fault recovery. The analysis method can be used as an evaluation method to check the steady-state transmission capability of HVDC transmission systems in actual operations.