Voltage control system and transient analysis of DG interfaced dc distribution system

In the liberalized power energy market, the delivery of electrical energy with high power quality to the supplied customers can be achieved through low voltage dc distribution systems. The design process of a dc system, where DG and storage system are interconnected, requires the selection of the most suitable devices for responding to the necessities and requirements of the optimal functioning of the power system. The energy management of the proposed dc grid requires the choice of an optimal control strategy for obtaining the best performances of the system through: realization of a bidirectional flow ac-dc; insurance of a high degree of voltage quality and supply continuity; interconnection and efficient use of DG and storage systems. The fast and safe isolation of the dc fault, such that the dc distribution system equipments are not damages, is the most challenging task. The simulations demonstrate the feasibility and correct operation of the system control logic and the dc protection strategy.