The excess of short circuit currents (SCC) has threatened the security of electrical energy transmission and become one of the most critical problems in power grid operations.
At present, high voltage direct current (HVDC) transmission technology is a practical and applicable option to limit short circuit currents by separating a synchronous power grid into several asynchronous power grids
During the transmission expansion planning, the short circuit currents can be effectively limited by strategically converting
alternating current to high voltage direct current transmission systems, improving transmission capacity as well.
Due to the high construction cost of high voltage direct current transmission systems, improper conversion would influence the economy of power system planning and the effect of short circuit currents reduction. Therefore, an approach of optimal transmission conversion (OTC) for limiting short circuit currents is proposed in this paper.