Development of UPS-SMES as a protection from momentary voltage drop

We have been developing the UPS-SMES as a protection from momentary voltage drop and power failure. The superconducting system is suitable as electric power storage for large energy extraction in a short time. The most important feature of superconducting coil system for the UPS-SMES is easy handling and maintenance-free operation. We have selected low temperature superconducting (LTS) coils instead of high temperature superconducting (HTS) coils from the viewpoint of cost and performance. However, it is difficult for the conventional LTS coils to fulfill maintenance-free operation since the cooling methods are either pool boiling with liquid helium or forced flow of supercritical helium. Thus, a conduction cooled LTS pulse coil has been designed as a key component of the UPS-SMES. The development program of 1 MW, 1 sec UPS-SMES is explained

Development of 1 MJ Conduction-Cooled LTS Pulse Coil for UPS-SMES

A 1 MW, 1 s UPS-SMES is being developed for a protection from a momentary voltage drop and an instant power failure. As a key technology of the UPS-SMES, we developed a prototype LTS pulse coil with a stored energy of 100 kJ and conducted cooling and excitation tests in 2005. The operation test of the prototype UPS-SMES using this 100 kJ coil with power converters have been performed in 2006. A 1 MJ coil was designed before the fabrication of the 100 kJ prototype coil. The superconductor, the electric insulation technique, the winding method, and the cooling structure used for the 100 kJ coil were based upon the 1 MJ coil design. The successful performance test results of the prototype 100 kJ coil validated the design concept and fabrication technique of the 1 MJ coil. According to the achievement of the prototype 100 kJ UPS-SMES, the 1 MJ conduction-cooled LTS pulse coil has been fabricated successfully. The successful experimental results of the 100 kJ prototype coil with power converters and the fabrication procedure of the 1 MJ full size coil are described