A New Approach to the Use of Energy from Renewable Sources in Low-Voltage Power Distribution Networks

Abstract

Currently, in rural networks with a large amount of distributed generation, PV installations are often disconnected due to the excessively high voltage in the network, which often exceeds the limit value, in accordance with the PN-EN 50160 standard. Disconnecting such an installation extends the return on investment costs by preventing the generation of electricity for the owner’s needs and results in the consumption of this energy from the grid. In such a case, the recipient has to bear the costs related to the purchase of this energy. In order to solve the problem of excessively high voltage in a low-voltage distribution network with a large amount of distributed generation, the authors of this article proposed a new approach to the use of electricity from these sources. In order to present the benefits of the proposed solution, a computer simulation was used. In order to carry it out, a mathematical model of a low-voltage power grid with distributed generation was developed using the electric multipole method and Newton’s method, which is discussed in the paper. To determine the advantages of the proposed solution, nine variants of the operation of an exemplary low-voltage power grid over one day were analyzed. The main conclusion based on the analysis of the results is that the proposed approach improves the operation of the power system by maintaining the voltage values within the standard range for the entire tested part of the network. In addition, the proposed approach does not increase the power or electricity when generating electricity from a PV installation. The proposed solution can also serve as a very attractive stimulus for the creation of energy cooperatives.

Keywords

• photovoltaic (PV)
• low-voltage (LV) distribution network
• power quality
• grid impact
• mathematical modeling
• power losses