Multiobjective Optimization Design of Small-Scale Wind Power Generator With Outer Rotor Based on Box–Behnken Design

In this paper, the finite-element method (FEM) based on 2-D numerical analysis was used for the basic design and characteristics analysis of a small-scale 3-kW wind power generator to which a permanent-magnet generator was applied. A prototype was manufactured, and a characteristics experiment was performed to verify the designed generator. In addition, the optimization design in order to satisfy required power of a generator while minimizing the cogging torque and the back electromotive force (EMF) total harmonic distribution (THD) on the basis of the designed initial model generator was conducted using the Box-Behnken design (BBD), which is a response surface method (RSM). The cogging torque, the back EMF THD, and the output power for each level of the design factors selected by the BBD were derived by the FEM based on 2-D numerical analysis. As a result, the optimal design model was derived in consideration of the RSA among each factor and the main effect and the interaction effects of each factor. This demonstrated the validity of the optimized design of the urban small-scale wind power generator design using the BBD.