A Comprehensive performance assessment of the integration of magnetic bearings with horizontal axis wind turbine

Abstract

This paper presents a comprehensive performance assessment for the use of Magnetic Bearing (MB) with Wind Turbine (WT). It is reported that this integration aims to improve the WT performance by eliminating fractional losses, mitigating vibration, reducing cut-in speed and prolonging the life span. However, there is no thorough studies regarding this integration in the literature to show in what extent the power generation will be affected in comparison with the use of conventional mechanical bearing (CB). This task constitutes the aim of this work. First, the main shaft of an existing conventional WT is redesigned to match the assembly with the MBs. Second, the design of two Radial Homopolar Pole Biased Hybrid Magnetic Bearings (RHPBHMB) and one Axial Active Magnetic Bearing (AAMB) is introduced. The MB design is analyzed using nonlinear magnetic circuit analysis and FEM. The MSC Marc software is employed to build 3D and 2D FEM models for the two radial and axial MBs respectively. Thirdly, the mathematical dynamic equations for the overall system is derived and an elaborated multi-disciplinary dynamic model is built using Simscape package. In addition, a robust intelligent TSK fuzzy Q-parameterization controller is synthesized to stabilize the RHPBHMB in order to achieve robust stability, overcome model nonlinearity and reject the step and sinusoidal imbalance disturbance at any rotational speed. Finally, an extensive comparison between the performance of the WT supported with Conventional mechanical Bearing (WT-CB) and the WT supported with Magnetic Bearing (WT-MB) is provided. The results show the ability of MB to defeat the disadvantages of the Conventional mechanical Bearing (CB), as well as, enhance the WT performance without decreasing the power generated.