A design strategy is presented to prevent irreversible demagnetization and reduce detent force in a single-sided permanent magnet linear synchronous motor (PMLSM) using Nd-bonded magnets. Nd-bonded magnets are susceptible to irreversible demagnetization under high temperature and armature reaction due to lower residual flux density ( \({B_r}\) ) and coercivity, whereas higher resistivity and lower flux density reduce eddy-current loss and detent force. The trade-off between magnet variables and performance was quantified by 3-dimensional finite element analysis (3D FEA) through recoil \({B_r}\) reduction and detent force. A surrogate-based multi-objective optimization with an evolutionary algorithm is conducted, and the optimized design is validated against the initial model. The framework integrates high-fidelity 3D FEA with surrogate based multi-objective search and is a design-oriented methodology for minimizing irreversible demagnetization and detent force in PMLSMs. Beyond this study, it can be extended to other topologies and operating conditions, offering both academic insights and practical value for industry application.
