Research On The MW Permanent Magnet Wind Power Generator Based On Halbach

In recent years,with the deterioration of the environment,the energy crisis in our world is becoming more and more serious,and more and more attentions have been paid to the research of renewable energy sources.Wind power generation is the most widely used in the all of renewable energy.Permanent magnet motor has a lots advantages,such as simpler structure,lower cost and better low speed.The design and manufacturing of large scale direct-drive and half-direct-driven permanent magnet power generator is the important part of the development of wind power generation,it has been leading technology as the research hot-point.In this paper,a new type of magnet array is introduced on the basis of the traditional large scale direct-driven and half-direct-drive wind turbines.First of all,according to the basic electromagnetic theory and previous research,learning from the traditional permanent magnet motor modeling,simple mathematical derivation of array magnetic field have been made to deduce the influence factor of permanent magnet wind turbine based on Halbach.The result shows that the air gap flux density of permanent magnet based on Halbach array have closely relationship with the thickness of permanent magnet,the magnetizing strength,wind generator pole arc coefficient,the number of poles and the motor radius.Secondly,according to the electromagnetic theory,the finite element analysis method and ANSYS Maxwell software modeling method,established direct-driven and half-direct-driven wind turbines two-dimensional finite element model,and according to the characteristics of the Halbach array to model at the same time.Finally,a large number of finite element simulation data are used to analyze the different results.By comparing the traditional permanent magnet generator and permanent magnet generator based on Halbach array,we can see that the permanent magnet generator based on Halbach array has a better effect in large permanent magnet generator.Compared to the traditional permanent magnet generator and permanent magnet generator based on Halbach array,the results show that the motor based on Halhach array has lower air gap flux density waveform distortion,and the Halbach array has more advantages when used by the small size permanent magnet generator.According to the calculation of permanent magnet eddy current loss,the permanent magnet based on Halbach has lower eddy current loss than the traditional array,so as to reduce the temperature of permanent magnet wind turbine,and that can improve the efficiency of wind turbines.According to the simulation with different pole number,the Halbach array get the amazing effect,the Halbach array should be fully taken into consideration used in motor field.This paper through the two dimensional finite element modeling and computation,and concludes the rule which Halbach array used by large permanent magnet direct-driven and half-direct-driven generator based on the law of electromagnetic field,provide a meaningful research for the design and research of a new MW permanent magnet generator.