Multi-Objective Optimization Applied to the Matching of a Specified Torque-Speed Curve for an Internal Permanent Magnet Motor

Traditionally, the objective function used for optimizing the design of an internal permanent magnet motor (IPM) has maximized efficiency or torque for a particular current or volume. Creating a particular torque speed curve can be considered to be a multi-objective problem and would usually be expressed in terms of a single objective by minimizing the average error over the curve. In this paper, it is proposed to treat this directly as a multi-objective problem thus allowing the designer to decide which tradeoffs in the torque-speed performance are most acceptable after the analysis has been performed rather than before. Additionally, a new variant of a multi-objective evolutionary algorithm using mixed elitism, intended for this problem, is described.