This paper deals with the steady and dynamic states analysis of induction motor using finite element analysis (FEA) approach. The motor has aluminum rotor bars and is designed for direct-on-line operation at 50 Hz. A study of the losses occurring in the motor performed at operating frequency of 50Hz showed that stator copper loss and rotor copper loss were higher than the other types of losses like the stray, iron core, frictional and windage losses. The motor efficiency based on material design was also studied at operating temperature. The materials considered in this paper are iron, nickel and cobalt. It was observed that iron at 75°C provided the best efficiency than other materials. The steady and dynamic states characteristics of the motor at rated load and on no-load conditions were observed. The flux levels at these loading conditions were also monitored.

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The switched reluctance motor (SRM) is among the special purpose electric machine family. It is simple in construction and avoids use of magnet so it is cheap to manufacture. The magnetic characteristics and simulation of three phase 12/8 switched reluctance motor (SRM) for enhanced starting torque is presented. The motor was analyzed using finite element technique (FET) and it was improved by focusing on the impact of important geometrical parameters on torque and efficiency. From the simulated results, the motor attained maximum efficiency of 91.7% at a speed of 1648.6 rpm and recorded a maximum torque of 321.1 Nm at a speed of 34.4 rpm. The magnetic flux lines and densities were also recorded. The maximum and minimum magnetic flux lines of the motor as observed were 1.2x10-3 Wb/m and -8.5x10-4 Wb/m respectively while the respective values of the maximum and minimum magnetic flux density of the motor were 3.8x10-1 T and 2.11x10-9 T. The results show that most of the field energy is confined within the motor and also concentrated in the air gap region of the motor. Dynamic analysis of the motor was performed for 0.02 s at a damping coefficient of 0.71 μNms/rad. The results showed that the motor has lower torque ripple. The preference to use this type of motor where high speed operation and better starting torque are needed has been highlighted in this study. Keywords:  Switched reluctance motor, static characteristics, transient analysis, torque, magnetic flux