Impact on on-load TAP-changer transformers in industries due to high penetration of photovoltaic distributed generation

In recent years, there has been a growing emphasis on diversifying and decarbonizing the energy matrix, paving the way for the emergence of new energy technologies as promising solutions for sustainable development. Among the emerging energies that have already achieved commercial maturity and deployment in Brazil are photovoltaic panels. This work proposes to analyze the potential impacts of on-load TAP-changers (OLTC) in transformers in industries located in distribution networks with a significant presence of photovoltaic distributed generation (PVDG). Thus, three industries are strategically allocated at different points of the IEEE 8500-node system using the OpenDSS program. The impacts are evaluated in several PVDG penetration scenarios in the network. The results show substantial fluctuations in the flow of energy generated by PVDG within the low-voltage network. This, in turn, induces frequent voltage changes in the medium-voltage network, leading to an increased operational frequency of OLTCs and a subsequent reduction in their lifetime. Moreover, this paper proposes alternative configurations for voltage regulator devices to enhance their lifetime in the face of intermittent voltage variations. The results suggest that adjusting the equipment's actuation delay and bandwidth of the OLTCs can decrease the OLTC switching frequency in a range of 65-85%, resulting in the preservation of the equipment's lifetime.