Fault current limiter based on series active compensator

Series active compensator (SAC) is a custom compensator utilized in power distribution network, however, due to connected in series with distribution line then SAC would suffer from large current flows due to downstream faults. To limit the flow those fault currents and protect SAC itself as well, a fault current limiting (FCL) function is proposed. Fault current limiting function of SAC will be activated by protection system and then SAC will start injecting a series voltage to the line in such a way to limit fault current to an appropriate level. The contribution of this proposal is the utilization of signals from existing feeder protection system to activate and terminate the FCL. This control simplifies the structure of SAC because the extra build-in fault detection module is not required. Moreover, it will ensure proper coordination between SAC and existing protection systems. Other benefits could be the voltage sag mitigation effect for upstream buses in case fault occurs at downstream section.