Application of Quasi-Force-Free Winding Concept to Superconducting Magnetic Energy Storage

The ratio of energy stored in the magnet to the mass of the structure required to withstand the electromagnetic load is known to be one of the most important characteristics of a system used as a superconducting magnetic energy storage (SMES).The concept of quasi-force-free winding, when applied to the design of the SMES magnet system, shows the way to increase the energy to mass ratio and allows to develop new SMES systems with technical and economical parameters better than the existing ones. This paper presents some progress in development of the concept for the SMES with stored energy up to 10 GJ and describes the steps of scaling the "large SMES project" towards a representative model for lab testing. The lab model has been manufactured and tested. The results of the magnetic measurements performed on the lab model confirm the correctness of the main theoretical assumptions which the concept is based upon and, in some way, a possibility to produce the SMES with a high energy-to-mass ratio.