Multi-terminal flexible direct-current transmission receiving-end power grid access point selection method and system

The invention discloses a multi-terminal flexible direct-current transmission receiving-end power grid access point selection method and system. The method comprises the steps: selecting key areas ina receiving-end power grid and alternative substations with flexible direct-current access conditions in the key areas; selecting one alternative substation from each key area to form an access scheme; counting the path length of a newly-built line required by each access scheme, calculating and counting the network loss and area short-circuit current level of each access scheme, constructing a path length matrix, a network loss matrix and a maximum short-circuit current matrix of the newly-built line, carrying out normalization processing, constructing a multi-terminal flexible direct-currentaccess scheme target function, and solving the minimum value of the target function; and obtaining an optimal alternative substation scheme of multi-terminal flexible direct-current access. The invention also discloses a corr