Investigation into spacing restriction and layout optimization of wind farm with multiple types of wind turbines

Abstract

In this paper, a new Directional Restriction method is presented to restrict the spacing between wind turbines. Compared to existing restrictions, the new method additionally considers the influence of wind directions, and the restriction for each wind turbine is related to its rotor diameter. Therefore, the method is especially effective for the site with obvious prevailing wind directions. With the Directional Restriction, a wind farm optimization process applying the Multi-Population Genetic Algorithm has been presented. The optimization can exploit the wind resource more effectively and can be used to optimize the layout of nonuniform wind farm. Four representative cases are then studied and discussed: (a) aligned layout with uniform wind turbines; (b) optimized layout with uniform wind turbines; (c) optimized layout with nonuniform wind turbines and (d) a commercial nonuniform offshore wind farm. Through these cases, the utilization rate of a nonuniform wind farm with five types of wind turbines can increase to 99.21%, in which the minimum utilization rate of a single wind turbine is 94.27%. Especially, in the last case, a potential offshore wind farm in Sha Chau Island in Hong Kong is analyzed. The results demonstrate that the proposed optimization method is practical in designing wind farms. The coastal area in Hong Kong is the ideal region to develop offshore wind power.