Two-Stage Dynamic Voltage/Var Control in Distribution Network Considering Uncertain Distributed Generations

After integrating distributed generators (DGs), the voltage/var control in distribution networks requires addressing multiple objectives, including power loss reduction, lifetime saving of mechanical switching voltage control devices and uncertain power output of DGs. Therefore, this paper proposes a two-stage voltage/var control method for distribution networks with uncertain power generation from DGs. A dynamic voltage/var optimisation model is formulated in the primary optimisation stage. It dispatches all the voltage/var controllers to minimise the action times of mechanical switching devices and the total active power loss over the day. The second stage consists of a stochastical optimisation model in which probabilistic scenarios replace the deterministic parameters of DGs and loads. The Monte Carlo approach and K-mean clustering technic are utilised to generate the scenarios to be used in the second stage. The DGs’ setpoints are recursively calculated to address the uncertainties. The proposed method is tested on a modified IEEE 33-node distribution network. The effectiveness of the method is demonstrated through the simulation results.