Performance of Superconductor Dynamic Synchronous Condenser on an Electric Grid

High-temperature superconductor (HTS) dynamic synchronous condensers have been developed for applications in an electric grid. The HTS dynamic synchronous condensers, also called SuperVARreg, are similar to conventional synchronous condensers, but the copper field winding has been replaced with an HTS field winding. The HTS dynamic synchronous condensers have some very attractive features, such as a small footprint, transportability, high reliability, and peak and dynamic reactive compensation capability for leading or lagging VARS. These HTS dynamic synchronous condenser machines are also inherently stable to close-in faults and can provide up to twice the nominal rating for about one minute (peak rating) during depressed voltage events. These machines also use about one-half of the energy of a conventional synchronous condenser because the HTS field winding losses are essentially zero. In October 2004, the first HTS dynamic synchronous condenser was installed on the Tennessee Valley Authority (TVA) grid serving an arc furnace where it is being exposed to a large number of transients, providing an excellent accelerated age test of the device. TVA has ordered five HTS dynamic synchronous condensers rated at 12 MVAR, and successful operation of the first prototype machine is expected to lead to release of these orders to production by TVA, making HTS dynamic synchronous condensers the first HTS commercial product for enhancing power grid reliability. This dynamic synchronous condenser machine will also be very attractive for dispersed generation applications (such as wind farms), for providing voltage regulation, and for improving the low voltage ride-through (LVRT) capability and for the decommissioning of older, less efficient "Reliability Must Run" generators