Hybrid AC/DC Microgrid Reconstruction in Rural Low-Voltage Distribution Grids to Enhance Electric Vehicle Penetration

In this paper, an easy-to-implement hybrid microgrid reconstruction scheme is proposed to enhance EV penetration in traditional rural low-voltage distribution grids. Unlike the traditional grid update solution, the introduced scheme reuses the existing transformers and power lines, and based on the energy routing unit (ERU), the AC distribution grid is converted to a hybrid microgrid. A prominent power transfer capacity increase and power loss reduction via hybrid microgrid reconstruction are quantified. Moreover, considering the efficiency characteristics of transformers and ERU, a power coordination strategy is designed to achieve optimal power dispatching between two feeders. The case study demonstrates that the maximum EV penetration in the reconstructed architecture could reach 352%, which is significantly superior to that in the traditional AC networks. Moreover, the overall efficiency and load ratio increase is realized under the reconstructed architecture.