Rotor Eccentricity Fault Of Permanent Magnet Synchronous Generator Based On Multiple Working Conditions

With the increase of the world's energy crisis and the enhancement of people's environmental awareness, the use of renewable energy has been paid more attention.Wind power as a clean and renewable energy, its development and utilization is particularly important. Generator in the wind power system is very important, its operation directly affects the quality and stability of the entire power system. Rotor eccentricity fault is one of the most common generator mechanical failure, the failure will change air gap and, distribution of magnetic field of the rotor core, intensified set,the vibration of the rotor and lead to deformation of the core and winding wear and insulation damage and other serious consequences. Therefore, based on the simulation model of the motor electromagnetic field analysis method, the permanent magnet synchronous wind turbine rotor static eccentricity fault research work is very meaningful.In this paper, the 1.5MW semi direct drive permanent magnet synchronous wind turbine is used as the research object. First, based on the working principle of permanent magnet synchronous wind turbine, in the power system analysis software MATLAB established semi direct drive permanent magnet synchronous wind generator simulation model, calculate the normal operation of the wind speed and mutation operation of generator terminal current, and in accordance with the motor theory and mathematical model calculation starting motor asymmetric short circuit operation is stable under short-circuit current. Secondly, according to the electromagnetic field theory and finite element analysis method, using ANSOFT finite element software established semi direct drive permanent magnet synchronous wind generator 2D static magnetic field model, and in the semi direct drive permanent magnet synchronous wind generator no-load operation, rotor and the normal operation of the rotor eccentricity running two to carry on the simulation computation, analysis of permanent magnet wind turbine generator rotor eccentricity electromagnetic fielddistribution and the air-gap flux density distribution of the variation. Finally, in the case of permanent magnet synchronous wind turbine with load operation, the normal wind speed operation, the wind speed mutation operation, single-phase short circuit operation, two-phase short circuit operation and other four conditions are simulated.When the generator rotor eccentricity, for each kind of operating a gas space path is defined after calculated under three different air gap semi cycle air gap flux density curves and gas gap energy density curve, and calculates the static rotor eccentricity under different conditions of operation of permanent magnet generator stator and rotor iron core magnetic force and analysis of effect of different conditions on the rotor of the generator static eccentricity. Finally, the corresponding data are compared to analyze the change of the additional loss of permanent magnet wind power generator under different operating conditions.The analysis method used in this paper will provide a reference basis for further research on rotor eccentricity, and the results obtained are expected to provide theoretical basis for fault detection and diagnosis of permanent magnet synchronous wind turbine generator.