Voltage and reactive power control have been widely employed to reduce power losses and satisfy the main distribution system operational constraints. In recent years, Distributed Generators connected to the distribution network have received increasing attention. The connection of enormous DGs into existing distribution network changes the operation of distribution systems and affect the daily Volt/Var control. Intermittent renewable resources, particularly wind and solar, or random changes in load level can cause significant fluctuations in distribution feeder voltages. This article presents a two-step control approach for finding the optimization feeder control settings and maintaining the feeder voltages and THD within specified levels by P-PSO optimization method. The load-tap changer transformers, voltage regulator and capacitor banks is controlled based on load and PV (with smart inverters) output 24 hours forecasting base on , while In order to reduce voltage fluctuations very short term output of PVs and load forecasting deal with the fast changing transients by output reactive power control. Evaluation studies are performed based on the harmonic IEEE 123 node radial test feeder under varying load and generation conditions. The results demonstrate that the proposed approach is promising for voltage and VAR control of distribution feeders with intermittent resources

Keywords: distribution systems, PV system, reactive power

Full-Text [PDF 1128 kb]   (5929 Downloads)