Optimized Design and Electromagnetic-thermalmechanical Analysis of a Toroidal D-shaped Superconducting Magnet in 5 MW LIQHY-SMES System

Compared with other energy storage devices, LIQHYSMES (the combination of liquid hydrogen and superconducting magnetic energy storage) systems have obvious advantages in conversion efficiency, response speed, energy storage capacity and have a bright prospect in power systems. Superconducting magnets are the electromagnetic energy storage units and the core components of LIQHY-SMES systems. In this paper, the electromagnetic optimized design of a toroidal D-shaped magnet applied in the 5 MW LIQHY-SMES system is completed by COMSOL and MATLAB co-simulation. In addition, the basic cryogenic system and quench protection system of the magnet are studied. Aimed at the difficulty of modeling and calculating the multi-physics field behaviors for toroidal D-shaped SMES magnets due to their complex structure, a method of electromagnetic-thermal-mechanical decoupling analysis is proposed, and the magnetic field distribution, AC loss, temperature rise and stress distribution during the operation of the designed magnet are studied. By this means, the stability of the designed magnet is verified, which provides a reference for toroidal D-shaped magnets to the multi-physics behaviors analyze.