Evaluation of a local DC load flow screening method for branch contingency selection of overloads

The author presents a novel screening method, involving a local DC solution, for branch flow limit violations (overloads) which, when incorporated with a performance index (PI) method, can greatly enhance the selection capabilities for online as well as study purposes. The local DC screening method and PI method are compared to results obtained from a full-system DC load flow assessment of two cases: a 24-bus system and a 584-bus representation of the Mid-Continent Area Power Pool system. The results indicate that, when these two methods are combined, excellent contingency selection capabilities are produced. The philosophy for this implementation and the details needed to implement the local DC screening method are presented.<>