Validation of Hybrid AC/DC Distribution Grids in the HYPERRIDE Project: Integration, Operation, and Performance in a DSO Environment

This paper presents a real-world implementation of a hybrid AC/DC distribution grid architecture, enabling enhanced control, flexibility, and resilience in low voltage (LV) networks. The demonstration was carried out by the Distribution System Operator (DSO) in the city of Terni (Italy) as part of the H2020 HYPERRIDE project. The pilot integrates a DC microgrid with existing AC infrastructure through bidirectional AC/DC and DC/DC converters, allowing seamless power exchange and supporting the operation of distributed energy resources, battery energy storage systems and electric vehicle charging infrastructure. A key innovation of this pilot is the implementation of a Low Voltage DC Soft Open Point (SOP) which links two MV/LV substations via AFE converters to enable dynamic, bidirectional power flow and enhanced fault resilience. A first operational scenarios regards stable grid operation and voltage regulation under both grid-connected and islanded conditions through converter coordination and droop control strategies; the second scenario regards the system's ability to support advanced energy management services such as peak shaving, PV power smoothing, and Vehicle to Grid (V2G) capabilities. Test results confirm the technical feasibility of hybrid AC/DC systems in real DSO environments and demonstrate their potential for scalable deployment.