Accurate Simulation Model of Variable Flux Machines under Asymmetrical Demagnetization without FEA Co-simulation

Variable-Flux Permanent Magnet Synchronous Machines (VFMs) employ low-coercivity permanent magnets whose Magnetization State (MS) can be dynamically adjusted through controlled current pulses. Achieving accurate MS regulation under load, while avoiding torque discontinuities, requires injecting current pulses that are not aligned with the magnets, resulting in asymmetric demagnetization. These nonlinear magnetization and demagnetization dynamics are not captured by conventional control-oriented models, and are typically analyzed using computationally expensive finite element analysis (FEA) co-simulations, which are impractical for control development and calibration.