A copper or another high-conductivity shield is often used for coating the solid rotor for reducing the armature-reaction space and time-harmonic-induced surface eddy-current losses in a solid-rotor synchronous machine. Since finite-element-simulation-based surface-loss evaluation for shield design can be very time consuming and complicated; a simple analytical model for calculating the surface losses is derived in this paper. A set of equations is derived based on Maxwell's equations for a general case and applied to a solid-rotor synchronous machine. Simulation results are provided to show that the proposed analytical model can serve as an effective screening tool for determining the optimal shield thickness for minimizing the rotor surface losses. The model is useful for assisting the shield-design process for synchronous machines with solid rotors, especially for high-speed machines operating in conjunction with power electronic converters.
Bibliographical noteFunding Information:
Paper IPCSD 05-113, presented at the 2005 IEEE International Electric Machines and Drives Conference, San Antonio, TX, May 15–18, and approved for publication in the IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS by the Electric Machines Committee of the IEEE Industry Applications Society. Manuscript submitted for review September 1, 2005 and released for publication February 21, 2006. The work of S. B. Lee was supported by a Korea University Grant.
- AC machines
- Eddy currents
- Harmonic analysis
- Magnetic losses
- Magnetic shielding
ASJC Scopus subject areas
- Control and Systems Engineering
- Industrial and Manufacturing Engineering
- Electrical and Electronic Engineering