Optimization of the generator to rotor ratio of MW wind turbines based on the cost of energy with focus on low wind speeds

Abstract

The effectiveness of a wind turbine to transform wind energy in electrical energy on a specific site depends heavily on its design, above all on the generator to rotor (turbine) ratio (GRR). In this research, the optimization of the GRR is focused with respect to the cost of energy (COE). Using a wind speed, a power generation, and a cost model, the Annual Energy Production (AEP) and the COE can be calculated dependent on the average wind speed, which is a site characteristic. The optimal GRR is shown with respect to the plant size and the wind class. A sensitivity function is interpolated which gives an idea for which type of site a plant is convenient. Moreover, the performance of existing plants has been evaluated for sites with low average wind speed conditions, where the funding and convenience of a wind park is particularly critical. As a result of the optimization, a reference plant design is proposed, which is optimal with respect to the models and reduces the COE in low average wind speed conditions.