Adaptive Droop Control of Multi-Terminal MVDC Distribution Network for High Solar PV Penetration

The MVDC distribution network has attracted numerous power system applications including renewable energy (RE) integration. Currently, there is growing interests in solar photovoltaic (PV) penetration in the distribution network. However, the PV grid penetration poses great challenges in the operation control of the distribution network in which the MVDC network can be a solution. In this paper, an adaptive droop-based DC voltage control strategy is proposed for increased PV penetration in the MVDC distribution network and validated in PSCAD/EMTDC. The results show that the proposed droop control accurately regulates the DC voltage hence the power flow in the network than the conventional droop control at 26 and 52% PV penetration. This provides the proposed strategy with a greater capacity to control higher PV penetration prior to possible PV power curtailment which is often the last resort. Future studies will extend the MVDC distribution network to encompass wind power and the proposed adaptive droop control strategy enhanced with the model predictive controller (MPC) or fuzzy-logic controller for better response and flexibility.