The present invention relates to an offshore wind farm cluster electrical
system planning method. On the basis of providing an onshore
power grid structure and all possible
grid connection points, a specific access capacity of each
grid connection point and onshore
power grid expansion are optimized according to a total access capacity of an offshore wind farm cluster by using an artificial fish school
algorithm; wind farm clustering is performed according to the access capacity of each
grid connection point obtained through optimization at an upper layer, and offshore
transformer substation locating and
sizing is optimized by using a
genetic algorithm; unified
topological optimization is performed according to a
transformer substation locating and
sizing result at a second layer, to obtain a new onshore grid connection point capacity and expansion result, the new onshore grid connection point capacity and expansion result is redelivered to a
fitness function of a second-layer geneticalgorithm, to guide offshore
transformer substation locating and
sizing, and repeated iteration is performed till the onshore
power grid structure is no longer changed, wherein an output is an optimalsolution. Compared with the prior art, according to the method, both economical efficiency and a reasonable degree after onshore power grid expansion are considered, and an onshore power grid and anoffshore wind farm cluster are integrated, to optimize costs and benefits.