Mobile Superconducting Magnetic Energy Storage for On-Site Estimations of Electric Power System Stability

Renewable energy and electric power liberalization have become important watchwords for present electric power systems. However, the stability of electric power systems is also a serious concern. Superconducting magnetic energy storage (SMES) systems are a promising candidate for the on-line evaluation of power system stability. From the viewpoint of the mobility of SMES systems, the authors carried out a design study on a 1 MJ-class mobile SMES system using MgB Rutherford cables. The results showed that 1) the 1 MJ-class mobile SMES components can be installed in a 40 feet dry container; 2) because of the effect of the force-balanced coil design, the SMES coil can be excited up to 2.0 T or 3.0 T without reinforcements for the MgB Rutherford cables; and 3) the 1 MJ-class mobile SMES coil can be cooled using 3 or 4 sets of conventional cryocoolers, including the cooling system for a 80 K thermal shield at a cooling temperature of 20 K or 10 K. Therefore, the engineering feasibility of the 1 MJ-class mobile SMES system using MgB Rutherford cables is confirmed.