Coupled 3D electromagnetic-dynamic modeling of radial-flux permanent magnet couplers

Purpose This paper aims to develop a new 3D electromagnetic analytical model in cylindrical coordinates to study the transient and steady-state dynamic performance of radial flux permanent magnet couplers. Design/methodology/approach The magneto-dynamic problem is addressed by coupling the proposed 3D electromagnetic model with the equations of motion and the circuit model of the drive motor. The electromagnetic model is developed by solving Maxwell’s equations in three-dimensional cylindrical coordinates using a magnetic scalar potential approach. The static torque expression is then derived from the Lorentz force, based on the electrostatic-magnetostatic analogy. Findings The obtained results demonstrate the accuracy of the proposed method, which accounts for magnetic edge effects without the need for correction factors. The magneto-dynamic model accurately predicts transient and steady-state performance while ensuring a good compromise between accuracy and computation time. Practical implications The 3D analytical model significantly reduces computation time compared to 3D finite element simulations, making it an efficient and accurate tool for designing and optimizing radial flux permanent magnet couplers. Originality/value A new 3D analytical model in cylindrical coordinates has been developed to compute the electromagnetic torque in radial flux permanent magnet couplers. This model inherently accounts for 3D magnetic edge and curvature effects without requiring correction factors. The 3D electromagnetic model is coupled with the dynamic equations to analyze both transient and steady-state performance.