Systematical determination of load flow cases for power system planning

This paper presents a novel method to determine a minimum number of representative load flow cases with load and generation data in a meshed transmission grid, which cover all critical power line loading situations in a given time frame. Measured active and reactive line loading data obtained from SCADA are the basic data input for this method. In order to find the optimum number of load flow cases a heuristic search algorithm in combination with a genetic optimization algorithm is used. The comparison of the required load flow cases with conventional load situations e.g. peak load or peak generation show, that conventional load flow cases do not cover all critical power line loading situations. Load flow cases determined with the presented method give an objective and representative picture of the expected situations and can be used for power system planning in the view of increasing demand and new generation capacity installations.