Abstract
Abstract. Over the past decade, the deployment of solar photovoltaic (PV) systems in electrical distribution networks has increased rapidly due to the declining cost of photovoltaic technologies and growing government support. This paper presents the development of an automatic power redistribution device aimed at mitigating voltage unbalance arising from the integration of electricity generated by solar photovoltaic systems into three-phase electrical networks.
Materials and Methods. Various technical solutions for voltage unbalance mitigation were analyzed, including three-phase system balancing systems, phase-switching and phase-selection devices, as well as three-phase and single-phase automatic transfer switching devices designed to monitor and switch between two power sources in electrical supply systems utilizing dual- or three-phase energy sources. In addition, the operating modes and functional schemes of smart electricity meters equipped with phase-selection devices for monitoring voltage unbalance indices were investigated.
Results. A functional scheme and control algorithm for a voltage unbalance mitigation device were developed. The proposed device enables the automatic redistribution of energy generated by a single-phase photovoltaic station among the phases of an electrical network when voltage unbalance occurs.
Conclusion. A device has been developed to regulate voltage unbalance and its associated indices in electrical networks, mitigate the increase in unbalance caused by the power generated by single-phase photovoltaic stations, and reduce power losses in distribution networks. As a result, phase-to-phase imbalance, power losses, and thermal losses can be reduced, while network stability and power quality are improved. The proposed device can be applied in distribution networks with widespread deployment of small-scale photovoltaic systems.
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