Sizing and siting of distributed generation in distribution systems for voltage improvement and loss reduction

The integration of distributed generation (DG) into the distribution system brings conspicuous technical and economic benefits to the grid. Yet installation of non optimized sizes of DGs at arbitrary locations can result in degraded voltage profile and increased system losses. This would consequently drive cost escalation, creating an effect against the desired. It is therefore expedient that the sizing and location of DG units should be prudently planned and determined. This paper presents an analytical technique to determine the optimal size and siting of DGs in a distribution system for active power loss reduction and voltage profile improvement. DG unit sizing and siting are calculated using a sensitivity index that combines the exact loss formula and voltage sensitivity coefficients. Investigation is carried out on the IEEE 13 bus test feeder to validate the effectiveness of the proposed method. Aspects related to the connection of non-dispatchable renewable DG to the distribution network and the use of energy storage, as a representative of smart grid technologies, is also discussed.