Study of Load Growth on Optimal Sites and Sizes of DGs Units in SUFALGEN 66 kV Sub-Transmission Network

The problem of voltage drop in distribution and sub-transmission system networks due to increased load growth can be solved by installing multi DG units identical photovoltaic, wind, geothermal and hydro on some network buses. This solution can reduce the real power losses and cost of generated energy from main plants. In this study, an adapted algorithm by MPSO modification particle swarm optimization has been applied to selecting the optimal site and size of fitting DGs units under diverse operating conditions in the SUFALGEN 66kV sub-transmission network in Libya. Furthermore, an impact study of load growth on the optimal site and size has been carried out to expect the optimal solution. DGs units Effects have been studied on a 49-bus sub-transmission test network using the three DGs units. A comparative study indicates that the optimal positions of DGs units don’t change with region load growth, while the optimal size modifications of the new three DG units change directly with region load growth. Re-pairing three DG units of new sizes confirms that the voltage profile alterations are within acceptable limits, as the least voltage decrease is 0.998 p.u.