Comparison of modular wind turbine generators considering structural aspects

Modular design of wind turbine generators is a promising means to increase the generator availability by reducing downtimes, especially for offshore turbines. With such physically modular designs, the structural support for the generator is an important consideration as it needs to overcome the loss of rigidity in the generator yoke. This makes the structural support design of the generator an important criterion when comparing modular topologies. This paper presents a comparison of modular generator topologies, both from an electrical and a structural performance perspective. It concludes that the 6/4 (6 slots in each stator module corresponding to 4 rotor poles) module is promising solution from the standpoint of maintenance, electrical performance, and structural performance.