Voltage Control of Distribution Grids with Multi-Microgrids Using Reactive Power Management

Low-voltage Microgrids can be valuable sources of ancillary services for the Distribution System Operators (DSOs). The aim of this paper was to study if and how multimicrogrids can contribute to Voltage Control (VC) in mediumvoltage distribution grids by means of reactive power generation and/or absorption. The hierarchical control strategy was proposed with the main focus on the tertiary control which was defined as optimal power flow problem. The interior-point algorithm was applied to optimise experimental benchmark grid with the presence of Distributed Energy Resources (DERs). Moreover, two primary objectives were formulated: active power losses and amount of reactive power used to reach the voltage profile. As a result the active power losses were minimised to the high extent achieving the savings around 22% during entire day.