Novel Topology Optimization Method for Weight Reduction in Electrical Machines

This paper proposes a combined electromagnetic and mechanical topology optimization for weight reduction in electrical machines based on Finite Element Analysis (FEA) and Evolutionary Structural Optimization (ESO). The devised method is an on- off-type algorithm with adaptative mesh in which low flux density and low Von Mises stress cells are removed successively from a first machine design. With this approach, the weight of the machine can be considerably reduced without compromising the electromagnetic performance of the machine, with a reduced computation time compared to other topology optimization methods. A case study involving a 1.2 MW low-speed, permanent magnet motor is analyzed under different conditions (algorithm parameters, initial mesh, rotational speed) and used to compare the proposed method with two other topology optimization approaches.