2Head of Stationary Equipment Design, R&D Department, MAPNA Generator Engineering and Manufacturing (PARS), Karaj
چکیده
In this research physical (e.g., density) and mechanical (e.g., Young’s modulus, etc.) properties are extracted via non-destructive testing (NDT) method for the stacked stator core of a 50 kW permanent magnet synchronous motor. Mechanical properties like Young’s modulus, Poisson’s ratio, etc. are essential parameters for the mechanical design of a component. As known, electric motors are comprised of two main parts, namely stator and rotor. In permanent magnet (PM) machines, the rotor of the electric motor includes some permanent magnets instead of windings; but the stator consists of windings to form the magnetic field. The stator core is made of a stack of coated electrical steel sheets or laminations, which are pressed together with tension bolts and tension bars or welded together in some cases. This matter causes different mechanical properties in axial and other directions. For electric machines such as induction and synchronous machines, the stacking pressure determination of the stator core is one of the major steps in machine design. The integrity of the stator core depends on the proper implementation of aforementioned step. The stacking process of the stator core of this type of electric (PM) machine comprises of three main stages including applying the stacking pressure, laminations welding under pressure, and releasing stacking pressure. These steps run as some static processes. In this study, the density and Young’s modulus of the stator core of a certain 50 kW PM electric machine in various directions are extracted using a non-destructive testing method. The non-destructive testing method utilized in this work is experimental modal analysis. Using the natural frequency obtained from modal test as the objective function and implementing the FEM optimization, the material properties are presented.
Material properties extraction of the stator core of a 50 kW permanent magnet synchronous machine (PMSM) by means of nondestructive testing method
Authors
Abstract
In this research physical (e.g., density) and mechanical (e.g., Young’s modulus, etc.) properties are extracted via non-destructive testing (NDT) method for the stacked stator core of a 50 kW permanent magnet synchronous motor. Mechanical properties like Young’s modulus, Poisson’s ratio, etc. are essential parameters for the mechanical design of a component. As known, electric motors are comprised of two main parts, namely stator and rotor. In permanent magnet (PM) machines, the rotor of the electric motor includes some permanent magnets instead of windings; but the stator consists of windings to form the magnetic field. The stator core is made of a stack of coated electrical steel sheets or laminations, which are pressed together with tension bolts and tension bars or welded together in some cases. This matter causes different mechanical properties in axial and other directions. For electric machines such as induction and synchronous machines, the stacking pressure determination of the stator core is one of the major steps in machine design. The integrity of the stator core depends on the proper implementation of aforementioned step. The stacking process of the stator core of this type of electric (PM) machine comprises of three main stages including applying the stacking pressure, laminations welding under pressure, and releasing stacking pressure. These steps run as some static processes. In this study, the density and Young’s modulus of the stator core of a certain 50 kW PM electric machine in various directions are extracted using a non-destructive testing method. The non-destructive testing method utilized in this work is experimental modal analysis. Using the natural frequency obtained from modal test as the objective function and implementing the FEM optimization, the material properties are presented.
Keywords
Modal Analysis, FEM Optimization, PM Electric Machine, Material Properties
مراجع
1. Abdallh, A. Abou-Elyazied, Peter Sergeant, and Luc Dupré. "A non-destructive methodology for estimating the magnetic material properties of an asynchronous motor." IEEE Transactions on Magnetics 48.4 (2012): 1621-1624. 2. Tang, Zhangjun, et al. "Effects of material properties on switched reluctance motor vibration determination." 38th IAS Annual Meeting on Conference Record of the Industry Applications Conference, 2003.. Vol. 1. IEEE, 2003. 3. Zec, Mladen, et al. "Finite element analysis of nondestructive testing eddy current problems with moving parts." IEEE Transactions on Magnetics 49.8 (2013): 4785-4794. 4. Yin, Hongbin, et al. "Research on equivalent material properties and modal analysis method of stator system of permanent magnet motor with concentrated winding." IEEE Access 7 (2019): 64592-64602. 5. Helbling, Hugo, et al. "Effect on magnetic properties of inhomogeneous compressive stress in thickness direction of an electrical steel stack." Journal of Magnetism and Magnetic Materials 500 (2020): 166353. 6. Chai, Feng, et al. "Accurate modelling and modal analysis of stator system in permanent magnet synchronous motor with concentrated winding for vibration prediction." IET Electric Power Applications 12.8 (2018): 1225-1232. 7. Zhou, D., et al. "3D vibration analysis of solid and hollow circular cylinders via Chebyshev– Ritz method." Computer methods in applied mechanics and engineering 192.13-14 (2003): 1575-1589. 8. Wu, Shengnan, et al. "Electromagnetic vibration analysis of high-speed permanent magnet synchronous machines with amorphous metal stator cores considering current harmonics." IEEE Transactions on Industrial Electronics 67.12 (2019): 10156-10167.
