Research And Design On Permanent-Magnet Wind Generator

As one of the renewable energy technologies had development prospect, wind powerattracted high attention around the world. In recent years, investigations of the vertical axiswind turbines(VAWT) received wide concern of scholars domestic and oversea. Comparedwith the conventional horizontal axis wind generators, VAWT without wind device andaerodynamic noise has merits such as ground maintenance, easy to inspect, long operatinglife and wide application field. It turned out to be an important aspect of wind generator forfuture. Main contents of this paper are as follows:Firstly, combining with the principle and analytical expression of cogging torque, theinfluence of pole arc factor to cogging torque is studied, and the cogging torque isobviously weakened through optimization of pole arc factor. Then the influence oflamination bridge shape to cogging torque is studied. Researches shows that optimizationof lamination bridge shape can improve the distribution of air gap flux density in transitionregion, which decreased ultra harmonic and cogging torque.Secondly, a VAWT of100kW and900revolutions per minute is designed throughscheme contrast and computing by FEM calculation. According to the design requirements,four schemes of different pole-slot combination designed, and performances such asefficiency, losses, material utilization, cost and cogging torque are compared and analyzed.Scheme of8-pole and72-slot is selected to be pole-slot combination of optimalperformance. Then， main parameters of8-pole and72-slot are optimized to determine theinitial design scheme, such as air gap length, slot size and serial number of turns per phase.Aiming at optimum of cogging torque, schemes are optimized through changing pole arcfactor and lamination bridge dimensions. Finally, rationality of design is verified bycalculation result of electromagnetic field.