Design and FE analysis of an outer-rotor PM generator for directly-coupled wind turbine applications

This paper presents the design and finite element (FE) analysis of a permanent magnet (PM) generator using neodymium-iron-boron magnets for directly-coupled wind turbine applications. To accomplish the goal of small size and light weight with an extra-low speed for direct coupling, the outer rotor structure is applied. The simple magnetic equivalent circuit approach is used for initial design iteration, and the finite element method applied to analyze the detailed characteristics. Comprehensive experimental tests were conducted to verify the theoretical predictions. A good agreement between the theoretical work and testing results was achieved.