Feasibility Study of Superconducting Current Limiter Application in a Cogeneration Plant

Fault current limiters (FCL) have been developed using high temperature superconductors. Possible applications of FCL are medium and high voltage energy supply systems. In this field conventional protection against high currents often cause high expenses. Using a superconducting FCL gives an economic advantage, if technical problems can be solved at lower costs or if the usage of a FCL makes savings in other equipment possible. This work deals with possible applications of a superconducting fault current limiter in a medium voltage auxiliary power network of a typical small cogeneration power plant. For possible installation locations in the existing energy supply system of Braunschweig, Germany, calculations of short circuit currents were made. It is investigated, whether the power plant can be expanded while staying or becoming short-circuit-proof. One result of the work is that the auxiliary power system of the power plant is an especially interesting installation location for a FCL. Advantages of a FCL compared to conventional strengthening of the installations are discussed.