Optimal Sizing and Placement of DG Units in Radial Distribution System

The continuous growth of electricity demand has presented a new challenge for power system utilities in preserving the system efficiency. Thus, Distributed Generation (DG) has attracted a lot of interest since it provides clean, reliable and cost-effective power supply. However, DG type, location and size should be properly chosen. To this end, this paper presents a DG placement and sizing method regarding system losses reduction, voltage magnitude and stability enhancement. The system weakest buses were selected for DG allocation in the basis of sensitivity methods and optimal DG size of a single DG unit has been determined by means of the quadratic curve-fitting technique. Multiple DG units' placement has been performed using loss improvement and loss reduction indices. Proposed approach has been applied to the 33- bus distribution system. Power system modeling and simulations have been performed using MATLAB\PSAT toolbox. Simulation results have shown accurate and satisfactory results in enhancing the steady-state voltage profile and decreasing total power losses.