Operation Schemes of Medium Voltage Distribution Networks with High Penetration of Distributed Solar Photovoltaics

The rapid development of small and mediumsized solar photovoltaics connected to the power distribution grids has led to many impacts on the management and operation of the grids. With a high penetration level, the power generated from these sources flows back to intermediate substations (at the level of 110 kV in Vietnam), leading to the risk of power transformer overload and increased losses on the grids. The paper focuses on calculation and analysis in different scenarios of these distributed solar photovoltaics in order to propose applicable operation schemes. The proposed grid restructuring solution using Grid Search Algorithm shows the prospect in reducing losses and improving voltage quality to the grid. Results of the paper obtained from a case study of specific medium-voltage grid of Vietnam will be a practical reference for distribution grid management and operation utilities.