State of the art of Fault Current Limiters and their applications in smart grid

We summarize the state of the art of Fault Current Limiters (FCL), focusing on devices in or near to field test status, and then, based on capabilities and characteristics of FCLs and smart grid, assign the various types to the most appropriate nodes in a smart grid.: 1) solid-state FCLs can be installed at microgrid and renewable energy resource feeders to replace circuit breaker and maintain protection coordination of the transmission network; 2) resistive superconducting FCL, saturated iron-core superconducting FCL and dynamic FCL can be installed at distribution substations to maintain downstream over-current protection without current harmonics disturbance; and 3) resistive and saturated iron-core superconducting FCLs can be installed at optimum locations in the transmission network to reduce fault currents to within a tolerable range when a new power plant is installed. With these placements, we can make full use of the advantages of smart grid´s communication network and different characteristics of FCL devices in different categories to offer a more flexible and reliable protection for future power grid.