Operation Scenario of Mobile SMES for On-Site Eigenvalue Measurement of Electric Power System

Eigenvalues are essential values for discussing the stable operation of the power system. However, the eigenvalues vary in real-time, and their distribution is complex in the power system. The authors conduct a design study on a 1 MJ-class mobile superconducting magnetic energy storage (SMES), enabling the eigenvalue measurement while changing locations. To achieve the weight saving and heat load reduction of the SMES coil, the authors applied the force-balanced coil (FBC) configuration to minimize the required mass of structures. Cryocoolers cool the SMES coil composed of MgB$_{2}$ Rutherford cables with a temperature range of 10 K to 20 K. The layout of the compressors requires at least 1 m away from the SMES coil due to the leakage magnetic field. The heat load calculation results show that the mobile SMES keeps over 90% of the energy cycle efficiency during the on-site eigenvalue measurement. Moreover, from the calculation results on the thermal time constant and the re-cooling time of the SMES coil, the eigenvalue measurement can immediately be restarted with the reduced power of SMES in urban areas. The eigenvalue measurement intervals in the suburbs will be every two days.