Evaluation of the design options and cost impact of improving induction motor efficiency

Aim of the paper is the evaluation of the manufacturing cost to move a motor from one efficiency class to the next one, with reference to the European Commission and CEMEP (European Committee of Manufacturers of Electrical Machines and Power Electronics) classification scheme: the analysis deals with low voltage three-phase, 4 pole, induction motors in the 0.7 divided by 90 kW power range. For each movement, the low cost design has been chosen, by considering several design strategies. The results of the study concern both the increase of Manufacturing Costs and Total Costs of the motor, and the percentage variation of active material costs respect to the "Reference motors" that represent typical commercial motors. The study was carried out in co-operation with several european Manufacturers that provided technical and economical data of commercial induction motors.