Large-scale offshore wind power cluster fan arrangement optimization method and system

The invention discloses a large-scale offshore wind power cluster fan arrangement optimization method and system. The method comprises the following steps: S1, dividing a large-scale wind power cluster area into a plurality of same small-scale wind power plant areas; S2, determining a medium-sized wind power plant of which the scale is smaller than that of the large-sized wind power cluster from the large-sized wind power cluster as an optimization object, wherein the shape of the optimization object is the same as that of the large-sized wind power cluster; S3, determining fan arrangement of the small wind power plant area with the minimum wake flow loss from the fan arrangement candidate points by using a random search algorithm; and S4, calculating the wake flow loss of the large-scale wind power cluster area, and when the wake flow loss of the large-scale wind power cluster area does not conform to the expectation, expanding the scale of the optimization object, and skipping to the step S3 until the wake