Effect of the distribution of the laminations in an axially laminated reluctance motor

This paper discusses the benefits for an axially laminated reluctance (ALAREL) motor deriving from a nonuniform distribution of the rotor laminations and from use of grain-oriented steel. It is shown that higher torque-to-current ratios may be obtained by rearranging the rotor laminations. An analytical model is firstly presented for a preliminary analysis. Then, a finite element analysis (FEA) is used for better estimation of the motor inductances. A comparison between calculated and measured inductances confirms the FEA accuracy. Thus, FEA is adopted to investigate the effect on motor performance of a nonuniform distribution of the laminations in the rotor as well as the effect of the magnetic material quality. The study proves that with nonuniform distributed and grain oriented steel laminations a higher flux linkage (up to 30%) can be obtained. Consequently, lower current is required to develop the same motor torque