A comprehensive overview, behavioral model and simulation of a Fault Current Limiter

Distribution systems across most parts of the globe are highly radial in nature. As loads are gradually increased on a particular distribution system, a higher operating current state leading to increased fault current levels is attained. Hence, the relay co-ordination is disturbed and equipments such as feeders and circuit breakers need to be replaced with higher rating so that they can handle the new currents often leading to expensive retrofit costs. The use of fault current limiter (FCL) is proposed to mitigate the effects of high current levels on a distribution system. A comprehensive and up-to-date literature review of FCL technologies is presented. Detailed efforts of an in-house developed behavioral superconducting FCL model are delineated, including FCL control algorithm and its implementation in PSCAD/EMTDC environment. Results from simulation studies are investigated and compared to an actual FCL commissioned by Z-energy to highlight the effectiveness of a generic model without having to access proprietary details. Extending those concepts, a solid-state and hybrid type of limiter is also modeled and it results discussed. Finally, an impact assessment is conducted on the distribution protection scheme, due to the FCL being inserted and subsequently operated in the distribution system.