Optimization Design and Characteristics Research of Linear Generator Based on Harmonic Analysis

Abstract

In the superconducting electrodynamics suspension (EDS) maglev, using the harmonic magnetic field of the 8-shaped coil to generate power is an effective way to address the vehicle power supply problem. This article proposes an analytical calculation model that comprehensively accounts for the magnetic field coupling among superconducting coils, 8-shaped coils, and collector coils in the topology of linear generators for EDS maglev. Firstly, by introducing the pole distance ratio k between the superconducting coil and the 8-shaped coil, the magnetic flux density distributions of the superconducting coil and the 8-shaped coil were obtained using harmonic analysis. Secondly, the mathematical expression for the maximum output power of the linear generator was derived. Furthermore, based on the principle of virtual work, an analytical model for the suspension and guiding forces of the EDS maglev, accounting for the influence of the linear generator, is constructed. Finally, linear generators corresponding to different 8-shaped coil structures were established, and the air-gap magnetic field distribution, power-generation characteristics, and dynamic performance of the EDS maglev were compared and analyzed. The analytical model proposed in this article can provide theoretical support for parameter optimization and system dynamic design of linear generators in EDS maglev.

Keywords

Superconducting electrodynamics suspension (EDS) maglev / Linear generator / Harmonic analysis / Output power / Suspension force / Guidance force

References

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