Conceptual Design Study of a Superconducting Flywheel System with Enhanced Speed Using Dipole Field

The high temperature superconductivity (HTS) technology present itself a bright future to be used in a flywheel energy storage system (FESS). In addition to the characteristics of conventional flywheel energy storage systems, the self-stability of high temperature superconducting maglev enables the suspension bearing to completely eliminate external control, improving the efficiency and stability of the whole system. And superconducting flywheel energy storage system can effectively eliminate the loss caused by mechanical friction and the electrical loss caused by resistance. In this paper, a superconducting flywheel system which is suspended and self-stabilized through the meticulous design of a high magnetic field is presented. The most obvious advantages are the reduction of mechanical friction, the use of Lorentz force to provide centripetal force instead of relying on mechanical limit of materials, and a higher speed than traditional flywheels. The optimization of the field distribution as well as the HTS coil of the flywheel is discussed. Subsequently, the energy storage efficiency, power density, energy ratio and suspension force of the flywheel are analyzed and compared in detail.