Research Of The Rotor System Of Magnetic Suspension Wind Power Generator

Along with the rapid consumption of coal, oil and other fossil fuels and the sustained development of low-carbon industry, wind power receives extensive attention from all over the world as a renewable clean energy. For the problem of large threshold velocity and frictional power loss of wind power generator using conventional mechanical bearings, a method to use magnetic bearing replacing the traditional mechanical bearings is proposed, which can reduce the threshold torque and threshold velocity, increase the annual power generation hours, and improve the utilization of wind power greatly.By analyzing several common magnetic supporting types of magnetic suspension wind power generator comparatively, the scheme of active magnetic supporting technology is chosen to be applied finally, then the structure selection of magnetic bearing is analyzed, also is the overall structure of the magnetic bearing system.The magnetic field analytical expressions of radial and axial magnetic bearings are derived. With the help of FEM analysis, the electromagnetic properties of radial magnetic bearings are simulated, the phenomenon of electromagnetic coupling and magnetic flux leakage is analyzed. The FEM solution is done from two aspects of air-gap magnetic induction intensity and electromagnetic force, which is compared with traditional analytical solution, based on this, the variation of air-gap magnetic induction intensity and the electromagnetic force with controlling current is obtained, which establishes the foundation for structure design and study of controlling system.The mechanical model of magnetic suspension rotor system is established, according to the mechanical model, the static and dynamic load of magnetic suspension wind power generator rotor is analyzed, and the maximum bearing capacity of front and back-end radial magnetic bearing and axial magnetic bearing is determined. On this basis, a detailed structural design and electromagnetic calculation of front and back-end radial magnetic bearing and axial magnetic bearing is carried out, including the structure analysis of stator and rotor, the design calculation of winding coils and so on. Finally, the power loss of radial and axial magnetic bearing is estimated, and check for coil temperature rise and the calculation of other parameters is completed.The starting point of this thesis is the research of new energy technology based on the wind power, which has good prospects. But the research of magnetic suspension wind power generator is just at an initial stage, this thesis only do some part of study on the rotor of magnetic suspension wind power generator from the theoretical analysis because of the constraints of my knowledge and research time. Therefore, the research of magnetic suspension wind power generator are not very comprehensive, there are still many problems in this area needing further research and improvement.