Wind farm layout optimization with multi-type wind turbines for minimizing levelized cost of energy

Wind farms with multi-type wind turbines have recently begun to be considered to improve space utilization efficiency and increase the economic benefits of wind farms. The layout optimization of this kind of wind farm is crucial for its development and is much more complicated than that of traditional wind farms with single-type wind turbines, as the wake interactions between different types of wind turbines are difficult to estimate and the costs of different types of wind turbines are uncertain. This study develops an improved wake model for multi-type wind turbines based on numerical simulation. Using this wake model, a series of wind farm layout optimizations are carried out to minimize the levelized cost of energy (LCOE), which considers power generation, construction cost, and maintenance cost. A maintenance cost model based on fatigue coefficients is introduced to assess fatigue damage due to uneven wind speed and turbulence. Single-type and multi-type layouts are compared in terms of LCOE, power generation, fatigue distribution, and maintenance cost. The results show that the economic benefits of multi-type wind farms are largely influenced by the wind turbine cost ratio, and a reasonable layout design can reduce the LCOE by 4.96 % compared to traditional single-type wind farms.