Convergence Acceleration of Topology Optimization Based on Constrained Level Set Function Using Method of Moving Asymptotes in 3-D Nonlinear Magnetic Field System

Topology optimization (TO) has advantages over shape optimization; for example, the design space is wider and the degrees of the shape freedom is larger. The convergence characteristic in the conventional level set (LS) method is slow because of the limitation of the time step size that is used for solving the simplified Hamilton-Jacobi equation, which is normally defined as the width of one finite element in the design domain. To overcome this difficulty, convergence acceleration using the method of moving asymptotes is investigated. The performance of the proposed method is compared with the conventional LS method for a 3-D TO problem regarding the magnetic shielding and an interior permanent magnet motor in a 3-D nonlinear magnetostatic field.