Implementation of a Coreless Axial-Flux PM Generator for Vertical-Axial Wind Turbine

In this paper, a rigorous and efficient approach, using the fuzzy-Inference Taguchi method with the multiple performance characteristics index (MPCI), is employed for obtaining the rigorous design of a small-scale direct-drive coreless axial-flux permanent-magnet (AFPM) generator for a vertical-axis wind turbine (VAWT) with both larger induced voltage and higher efficiency. The proposed method first establishes the orthogonal array (OA) recommended by the Taguchi method, then multiple targets are coordinated by the fuzzy inference mechanism to obtain a better combination of geometric parameters for achieving multiple quality targets. The three-dimensional (3-D) electromagnetic finite element method (FEM) is used as the tool for analyzing the performance of the coreless AFPM generator. The results have shown the proposed method can obtain the suitable generators geometric parameters for enhancing the induced voltage of the generator while keeping efficiency as high as possible under the rated speed.