Abstract
A high-conductivity shield is often used for coating the rotor of solid-rotor synchronous machines for reducing the surface eddy-current losses due to armature-reaction space/time harmonics and/or tooth ripple. Since the design process for determining the optimal shield thickness can be complicated and time consuming, a simple analytical model based on Maxwell's equations was developed and presented in a previous paper to simplify the process. It has been shown that such an analytical tool can be used as a quick and effective "screening tool" for determining the range of the optimal shield thickness for minimizing rotor surface losses; however, the influence of finite rotor axial length including the end-face losses was not taken into account. In this paper, an additional step is introduced in the shield design process where a special finite-element (FE) method that accounts for the impact of finite rotor axial length is employed for refining the design obtained from the analytical solution. Comparisons are made for a number of shield thicknesses and rotor lengths for significant space and time harmonic combinations to verify the validity of the proposed two-step design process (analytical and FE) and to evaluate the impact of the finite length of solid rotors.
Original language | English |
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Article number | 5238577 |
Pages (from-to) | 1947-1953 |
Number of pages | 7 |
Journal | IEEE Transactions on Industry Applications |
Volume | 45 |
Issue number | 6 |
DOIs | |
Publication status | Published - 2009 Nov |
Keywords
- Ac machines
- Analytical and numerical harmonic analyses
- Eddy currents
- Electromagnetic shielding
- Rotor surface losses
- Solid rotor
- Synchronous machines
ASJC Scopus subject areas
- Control and Systems Engineering
- Industrial and Manufacturing Engineering
- Electrical and Electronic Engineering