Robust restoration of distribution systems considering DG units and direct load control programs

Abstract

This paper presents a new method for restoration of distribution networks after a fault occurrence. Thisproblem is solved from the viewpoint of the distribution system operator with the main goal of minimizing the operatingcost during the fault clearance period. The effects of distributed generation (DG) units and direct load control (DLC)programs are considered in designing the proposed restoration procedure. Moreover, the uncertainties associated withthe predicted loads of different nodes and the availability of DG are modeled here. Robust optimization is used to modelthe uncertainties of restoration problems and manage their associated risks. Finally, a robust reconfiguration plan isobtained solving a bilevel problem using a genetic algorithm (GA). The upper-level problem is concerned with evaluatingthe optimum configuration by GA and the lower-level problem obtains the optimum schedules of DG and DLC with anAC optimal power flow. A 32-bus test system is used to demonstrate the applicability of the proposed method.