Cost-Efficient Selection of Stamping Machines for Lamination Production in the Electric Traction Motor Application

In the booming market of electrified mobility, product cost plays a crucial role for the competiveness of electric vehicles. Approximately 70% of the product costs are determined in the product development phase. Therefore, a cost evaluation of the product design in the development stage is necessary to check the achievement of cost target and if needed to modify the design as early as possible. To get a holistic view, not only the material cost, but also the manufacturing cost have to be taken into consideration. This work presents an approach to evaluate the cost of lamination stacks (stacking cost not included) used in electric traction motors of electric or hybrid vehicles. By following design of the lamination, the stamping process is modularized, which has an influence on the raw material utilization and manufacturing cost. Minimum cost of laminations can be achieved by increasing raw material utilization and decreasing manufacturing cost. The proposed model is developed for lamination cost estimation based on an optimum production decision, which is determined by selecting suitable stamping machine and proper mold design. The relationship between lamination design and the stamping process in terms of cost is illustrated under the condition of a fixed production volume. Finally, the influences of design changes on lamination costs are analyzed and the significance of this model is demonstrated.