IEEE Transactions on Energy Conversion, Vol.28, No.3, 543-552, 2013
Optimal Design of Adjustable Air-Gap, Two-Speed, Capacitor-Run, Single-Phase Axial Flux Induction Motors
In this paper, a new optimized structure for two-speed, capacitor-run, single-phase axial flux induction motor (AFIM) for direct-drive operation is presented. Although, there are many advantages for direct-drive systems, their axial forces between the stator and rotor increases with reduction in air-gap length and is of serious concern. An increase in the air-gap length will result in the deterioration of performance characteristics of the motor. In this paper, a new construction technique is proposed to fabricate an AFIM with adjustable air-gap length. After presenting a comprehensive design algorithm, all geometrical dimensions and electrical equivalent circuit parameters are analytically calculated. Then, a multiobjective and multivariable optimization for a high efficiency and power factor with minimum usage of core materials is carried out. Optimization process is verified using three-dimensional, time-stepping finite-element analyses, and finally, the prototype of the optimal motor is fabricated and tested. Good agreements between analytic, finite element, and experimental results show the success of the proposed design.
Keywords:Multiobjective and multivariable optimization (MOMVO) approach;single-phase axial flux induction motor (AFIM);time-stepping finite-element analysis (TSFEA)