Solar Photovoltaic–Small Hydro-Based Charging: Infrastructure for a Three-Phase, Four-Wire Distribution Network

Electrification of the transportation system IS needed to reduce carbon emissions. To ease the adoption of electric vehicles (EVs) by consumers, development of accessible charging infrastructure is required. However, the integration of charging infrastructure has adverse impacts on the distribution grid, due to the frequent connection and disconnection of vehicle loads as well as single-phase home loads. This article presents three-phase, four-wire (3P4W) renewable-based charging infrastructure that includes photovoltaic (PV)–small hydro energy conversion (SHEC) battery energy storage (BES) sources to provide power to local loads as well as incorporating ac and dc charging stations. Using a constant source, i.e., a hydrogenerator, reduces the intermittency of the sources. Besides, the integration of charging stations provides a reduction in energy curtailment. The generated PV power is utilized locally to increase the self-consumption rate, whereas the constant power generated from the SHEC is used to feed ac loads and EVs connected at the common point in conjunction with the utility grid. The system provides smooth grid integration, i.e., a dual-mode operation stand-alone mode and a grid-tied mode, between which it operates seamlessly. The harmonics introduced by the charging stations are suppressed using an improved multivariable notch filter (IMVNF). Moreover, the controller suppresses high neutral current due to the uneven distribution of the single-phase loads. Finally, the system is equipped with ancillary services, such as maintaining the power quality of the grid during frequent connection/disconnection of vehicle loads and home loads, undisrupted power to loads, reactive power compensation, and neutral current suppression. The system is simulated, and the results are validated on an OPAL-RT 5700 hardware-in-the-loop-based real-time simulator under various scenarios.