Design and Development of Three Phase Induction Motor Using Written Pole Technology

Abstract

Three phase induction motors are employed in almost all the industries because of its simple construction and easy operation. Efficiency of the induction motor is affected by its fixed losses and variable losses which mainly depend on the input supply voltage and load current respectively. An attempt is made to minimize the iron losses by using the permanent magnet ferrite. A new Three Phase Induction Motor Using Written Pole Technology is proposed in this paper whose stator consists of two three phase windings accommodated in the same core and rotor is used as squirrel cage rotor with ferrite material on its periphery. Shaft loads are categorized as low, medium and high, Stator windings are energized through a controller based on the load demand. When compared to conventional induction motor, the motor efficiency and power factor are improved. Another approach of this machine is that the ferrite layer on the rotor periphery will reduce the motor losses which results in improving the motor efficiency. In this motor, one windings (main winding) is designed for the 238 volt ac voltage while the second winding (exciter winding) is designed for 8 volt high frequency ac voltage. Experimental result ensures the considerable increase in the efficiency and power factor.