Medium Voltage to Low Voltage Load Flow Algorithm for Unbalanced Islanded Microgrids

In this paper, a load flow algorithm for unbalanced islanded Microgrids (MGs) is developed considering both the multigrounded low voltage (LV) and the medium voltage (MV) network. The method is based on the implicit Z
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load flow method and it can be applied even in highly meshed MGs regardless of the R/X ratio of lines. It presents fast convergence, low computation time and high robustness. In our analysis we consider a variety of transformer configurations and step voltage regulators. Simulations were conducted in IEEE 4-nodes, 6-nodes and in a highly meshed network of 749 MV and LV nodes.