Long-distance transmission of large-capacity clean energy to load center via DC is the development trend of power grid. Traditional measures for example strengthening the AC grid can no longer meet the requirements of safe and stable operation of multi-DC feeding receiving power grids. It is urgent to study the application feasibility of new flexible transmission technologies. This paper first analyzes the risks and challenges faced by the safe and stable operation of multi-DC feeding receiving power grids. Combined with the advantages of VSC-HVDC and aiming at the problem of limited transmission capacity of AC section caused by uneven power flow distribution, a VSC-HVDC layout method to maximize the transmission capacity is proposed and the effect of improving the transmission capacity of the VSC-HVDC grid-connected section is quantified. Aiming at the problem of multi DC simultaneous commutation failure caused by AC fault, a VSC-HVDC configuration method for reducing the risk of two DC simultaneous commutation failures is proposed and the reduction effect is quantified. The effectiveness of the proposed method is verified by taking the actual data of Henan Power Grid as an example. The configuration of VSC-HVDC in the key transmission section can fully exploit the potential of existing transmission equipment and improve the transmission capacity of the section, significantly reduce the range of AC fault areas that cause the two DC commutation failures, and improve the safe and stable operation level of the grid. This work is supported by National Natural Science Foundation of China (No. 51777196) and Science and Technology Project of State Grid Corporation of China (No. XTB11201703025).