Optimal Placement and Sizing of Distributed Generator in Meshed Distribution System

Voltage stability and reliability is the major concern in radial distribution system (RDS). Customer far away from the substation faces voltage reliability and system fluctuation issues. These issues should be resolved through different methodologies under smart grid paradigm. Studies proved that loop and mesh distribution systems (MDS) show better voltage reliability and stability than RDS. A comparative study of different load models is done in terms of losses, voltage profile and cost of active power losses in both radial and mesh distribution system. Two different multiple-criteria decision analysis (MCDA) techniques PROMETHEE and Weighted product model (WPM) are used to identifying the best decision by considering active power loss, voltage and cost of active power cost attributes. A distinctive voltage stability index (VSI) is used to find the critical bus which is highly sensitive to voltage collapse. The bus having lowest VSI value is the most critical bus which is optimal location for siting the distributed generation unit (DG). VSI is evaluated for both radial and mesh distribution network. Different load models; constant power (CP) and constant impedance (CZ) models are used in this paper. The impacts of CZ and CP load models have been observed on voltage profiles and system losses on IEEE 33 bus system.