Thermal Analyses and Calculations of 1.5MW Half-Direct Permanent Magnet Wind Power Generator when PM Embedded in Different Rotor Positions

The 1.5MW half-direct permanent magnet synchronous wind generator with 252 slots, 32 poles is investigated in this paper, and two kinds of generator designs according to permanent magnet embedded in different rotor positions are presented. Based on the fluid mechanics theory, the mathematical models of 3D fluid field that fluid flowing through the outer-surfaces of generators are established, and the distributions of heat transfer coefficients on outer-surfaces of half-direct permanent magnet wind generators are calculated. Meanwhile, the 2D thermal analysis models of machines are established according to the heat transfer theories, then the temperatures of generators in rated wind speed at load are analyzed and the temperatures of casing surface, stator windings and rotor are given. At last, the comparisons of the analysis results with the test data on a small wind generator with the same structure are proposed, which is meaningful for the design of large capacity of half direct permanent magnet wind generator.