Title :
Experimental verification of optimal flux weakening in surface PM Machines using concentrated windings
Author :
EL-Refaie, Ayman M. ; Jahns, Thomas M. ; McCleer, Patrick J. ; McKeever, John W.
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Wisconsin, Madison, WI, USA
Abstract :
Previous analytical work has shown that it is possible to design surface permanent-magnet (SPM) machines using fractional-slot concentrated windings to achieve wide speed ranges of constant power operation by satisfying the optimal flux-weakening condition. This paper presents a 6-kW 36-slot/30-pole concentrated winding prototype SPM machine that has been designed using a closed-form analytical technique developed specifically for this class of machines. Experimental testing of this machine has been carried out to determine its performance capabilities, including flux-weakening operation. Detailed comparisons between analytical, finite-element analysis (FEA), and experimental results are presented, which confirm the ability of fractional-slot concentrated winding SPM machines to achieve their high-speed operating objectives. Important issues including the machine´s back EMF voltage at top speed, eddy-current losses in the magnets, and inverter performance are analyzed and discussed in detail.
Keywords :
design engineering; finite element analysis; machine testing; machine windings; permanent magnet machines; 6 kW; FEA; back EMF; eddy current losses; finite element analysis; fractional-slot concentrated windings; machine testing; optimal flux weakening; surface PM machines; surface permanent magnet machines; Finite element methods; Inverters; Machine windings; Magnetic analysis; Magnetic losses; Magnets; Prototypes; Scanning probe microscopy; Testing; Voltage; Concentrated; experimental; flux weakening; fractional slot; permanent magnet; surface; synchronous; verification; windings;
Journal_Title :
Industry Applications, IEEE Transactions on
DOI :
10.1109/TIA.2006.870043
