A new voltage control scheme for active medium-voltage (MV) networks

The main objective of this paper is the effective voltage regulation in radial medium-voltage (MV) distribution networks with high distributed generation (DG) penetration, ensuring near-minimum active power losses. For this purpose, a new control strategy with low computational complexity is proposed. The method exploits the reactive power capability of DG units to mitigate overvoltages in coordination with the on-load tap changer of the high-/medium-voltage transformer to achieve power losses reduction. This is attained by introducing a time delay allocation method based on the graph theory to prioritise the response of DG units. The control scheme is further enhanced by the active participation of MV loads in the voltage regulation process, contributing to the reactive power control of DG units. To evaluate the performance of the proposed control strategy, time-domain and time-series simulations are performed in radial MV distribution networks. The former demonstrates the robustness and fast response of the proposed control scheme, while the latter highlights its improved power system performance over existing centralised as well as decentralised control methods.