Multimaterial Magneto-Structural Topology Optimization of Wound Field Synchronous Machine Rotors

A combined magneto-structural topology optimization approach based on the solid isotropic with material penalization method is proposed for wound field synchronous machines (WFSMs) to optimally distribute multiple materials including electrical steel, copper, and air in a rotor design domain. Magnetic topology optimization is simultaneously combined with structural topology optimization to ensure rotors, which are mechanically feasible. A topology optimization approach does not require the use of a geometric template where dimensions are controlled by parameters. Example designs of salient pole WFSM rotors are used to demonstrate the proposed technique. The proposed topology optimization technique is compared with a multiobjective optimization with the rotor geometry defined by a geometric template. For the same torque level the topology optimized rotor has lower copper losses.