A Refined Hybrid Analytical Framework Model for Homopolar Linear Synchronous Motor with Discrete Secondary Segments

Homopolar linear synchronous motors (H-LSM) represent a viable solution for high temperature superconducting (HTS) maglev requiring low-cost vehicle propulsion systems. However, due to the inherent 3D-field distribution of H-LSM, the necessary 3D finite element analysis (FEA) hinders its rapid design and optimization. This paper proposes for the first time a complete refined hybrid analytical framework model for H-LSM with discrete secondary segments. This model integrates the methods of airgap magnetomotive force-permeance, winding function theory, and conformal transformation, accurately considering the magnetic field modulation effects caused by discrete secondary iron segments and primary slotting, as well as the transverse and longitudinal end effects. The analytical predictions are verified by 3D FEA and a laboratory-scale prototype, demonstrating high agreement, which validates the effectiveness of the proposed model. This model reduces computational time by approximately 98% compared to FEA under the specific conditions, enabling rapid analysis and optimal design of H-LSM with complex 3D-field characteristics under arbitrary pole-slot combinations for HTS maglev applications.