Emergency power flow re-routing in a distribution system by using dynamic line rating

Abstract

Dynamic rating is a technology which allows loading power lines above their rated limits. More often, dynamic rating is used to transport new power and connect additional generators to the grid using existing infrastructure. However, this study explores the possibility to use dynamic rating for improving the security of supply and assisting fast reconnection of disconnected customers during emergency and fault situations occurring at other lines. DLR allows improving power system reliability during emergency conditions using Optimal Power Flow (OPF), which additionally helps to minimize costs of system operation. Large costs involving investment for new infrastructure and penalties for interruptions in the power supply can be considerably reduced by implementing DLR. Also, DLR can improve the reliability of the system by providing real-time information on the status of power lines. Using Optimal Power Flow ensures that the lines loading, bus voltage magnitudes and angles as well as generation injections are within the acceptable limits as per the utility regulations. Faults are modelled as cases when one of the lines becomes disconnected. The bottlenecks in the system during post-fault situations are identified to determine optimal lines in the system on which DLR could be implemented.