Resonant Fault Current Limiter for MV applications

The present article summarizes results of a concept study of a resonant-type Fault Current Limiter for a potential application in the MV networks, whose short circuit current exceeds limits of conventional MV breakers. The concept is based on the known idea of a non-saturable series current limiting reactor compensated, under normal operating conditions, by a series capacitor. In the present article it has been demonstrated that the application of the present state-of-art solid-state switching technology and a fast control circuit, together with appropriate selection of passive elements minimizing the overvoltage and overcurrent stress on components allows one to design a cost-effective MV device using low voltage components. The analysis is based on a realistic MV network case study with a high short-circuit current level. The process of selecting the system components has been demonstrated. A small-scale physical concept demonstrator has been built using standard, off-the shelf components. The experiments performed at reduced voltage and current conditions confirmed the simulation results.