Predicting Post Outage Transmission Line Flows using Linear Distribution Factors

Abstract

In order to design and implement preventive and remedial actions, a continuous performance of fast security analysis is imperative amid outages of system components. Following the contingency of a system component, State estimation and Load flow techniques are the two popular techniques used to determine system state variables leading to estimation of flows, losses and violations in nodal voltages and transmission line flows. But the dynamic state and complexity of the system requires faster means of estimations which can be achieved by linear distribution factors. The use of Distribution factors in form of Power Transfer Distribution Factors (PTDF) and Line Outage Distribution Factors (LODF) which are transmission line sensitivities with respect to active power exchanges between buses and transmission line outages offer an alternative to these two techniques being linear, quicker, and non-iterative. Following the estimation of the linear distribution factors from a reference
operating point (base case) and contingency cases involving line outage, generator output variation and outage of a Six bus network using Matlab programs, the results show that by means of Linear Distribution factors quick estimates of post outage line flows can be made which match flow results obtained from DC load flow analysis.