Modeling of Coupled Electric and Magnetic Circuits in Electromagnetic Suspension Vehicles

A comprehensive understanding of electromagnet behavior is crucial for advancing levitation system development, particularly in high-speed transportation. This paper presents a non-linear magnetic circuit model for analyzing static and dynamic behavior of a magnetic levitation system. The model accommodates iron saturation and the impact of eddy currents. It is validated and parameterized by comparing its behavior with experimental data obtained at a testbench. The static characteristics of the system are analyzed in terms of the magnetic force depending on current and the system’s air gap. Dynamic behavior is explored through the examination of inductance. We show how a differential algebraic structure of the model can be avoided by incorporating eddy currents in a specific way. Thereby, our approach solves mathematical difficulties and leverages physical accuracy to a level which makes the model highly appropriate for fast computation and dynamical analysis. The results obtained show that the proposed magnetic model is able to accurately predict the behavior of the magnetic levitation system over the entire operating range. In contrast to simpler models widely used in magnetic levitation design, the proposed model supports the design, optimization and model-based control of magnetic levitation systems, up to the real implementation within vehicle components.