The increasing share of intermittent renewable energy sources, the phase-out of controllable power generation units, and changes in electricity consumption behavior are significantly transforming the electric power system. By 2035, these changes will require greater flexibility from the demand side to ensure grid stability, particularly in Europe. Historically, domestic loads have contributed to frequency and voltage stability through their natural sensitivity to grid conditions. However, the widespread adoption of power electronics in consumer devices has diminished this inherent sensitivity.

This research project focuses on leveraging local electrical measurements to reintroduce automated and autonomous responsiveness in electric vehicle (EV) charging to enhance grid flexibility. Specifically, the project aims to develop a smart charging cable that modulates the EV charging power based only on local grid parameters such as voltage amplitude and frequency. This solution is particularly relevant for existing alternating current (AC) charging infrastructures (mode 3, single or three-phase), offering backward compatibility on existing charging station without requiring user intervention or centralized control.

The proposed system uses a hardware “man-in-the-middle” approach to dynamically adjust the control (CP) signals exchanged between the EV and the charging station. By altering this signal in real-time based on local voltage and frequency measurements, the cable can autonomously limit the charging power in response to grid disturbances, frequency deviations, or voltage reductions before for example activating the Load Frequency Demand Disconnection.

The methodology combines both scientific and technological components. Scientifically, it involves the development of an algorithm that determines optimal power limitation levels based on local grid conditions. Technologically, an LFSM-UC algorithm is integrated into a prototype smart cable that interfaces directly between any standard AC charger and an EV, ensuring real-time responsiveness without relying on telecommunications networks. This architecture provides robustness against communication failures, enhances grid stability, and minimizes environmental impact from additional infrastructure.

Preliminary lab tests using an EV emulator and several EV from different manufacturers confirm the cable's ability to quickly adjust charging power based on predefined voltage and frequency thresholds. The results demonstrate the feasibility of decentralized demand response in EV charging and offer a scalable, user-transparent solution to support future grid stability requirements.