Modeling of the work of the UFLS using the new component of the UFLS in the PSCAD/EMTDC software

The most severe consequences for the power system occur during system accidents with the occurrence of a large deficit in the generated active power and a deep decrease in frequency. To prevent and limit the frequency avalanche, a complex of automatic frequency reduction limitation (AFRL) is used, namely its main component is under frequency load shedding (UFLS). The UFLS device is one of the emergency control (EC) devices, which is not provided as a separate component in some of the leading computer systems. In this paper, it is developed a component that implements the functions of under frequency load shedding in the power system. The introduced study briefly discusses the modeling of UFLS processes in the PSCAD/EMTDC software and testing the operation of the component developed by the authors.