Comparative analysis of wind generator energy efficiency based on machine design

This paper presents a comparative analysis between the energy efficiency of two wind generator designs. A hypothesis is presented that generators for wind applications should be designed based on their energy efficiency instead of rated efficiency. As wind generators are working with variable rotational speeds and power levels, resulting in changes in their electrical efficiency, there is a need for a method to define machine efficiency during the design process. Designing the generator based on the energy efficiency gives the opportunity to optimize the machine in a more effective way. Comparison between a slotless and a conventional directly driven wind turbine generator is given.