Design and prototyping of outer rotor permanent magnet generator for small scale wind turbines

This paper describes the design and prototyping process of outer rotor permanent magnet generator meant for the use in small scale wind turbines. The initial design of the machine is presented. Main issues and phenomena, affecting the generator design, such as cogging torque and its reduction possibilities, selection and demagnetization risk assessment of permanent magnets, machine losses and thermal analysis is described. Test results of constructed prototype generator and final parameters are also presented. Necessity of further study is pointed out.