Researcher(s)
- Ethan Padilla, Electrical Engineering, University of Delaware
- Angel Robles-Ortiz, Computer Engineering, University of Delaware
Faculty Mentor(s)
- Willett Kempton, Electrical and Computer Engineering, University of Delaware
- Rodney McGee, Institute of Energy Conversion, University of Delaware
Abstract
The electrical grid is a highly versatile yet fragile piece of infrastructure that supports bidirectional charging. Part of bidirectional charging is Vehicle-to-Grid (V2G), a process where electric vehicles (EVs) can transfer energy back to the power grid. V2G-compatible vehicles can act as high-capacity batteries, providing relief to the electrical grid during high-demand periods using “smart” bidirectional electric vehicle supply equipment (EVSE). Current EVSEs struggle with accessibility for different connector types, with some using J1772, J3400, or others. This incompatibility forces owners to use improperly suited adapters, which pose a high voltage hazard to users. In the case of a “dumb” EV, this communication protocol incompatibility can prevent transmission of thermal or current sensing data, which can lead to high voltage arcing and/or cable melting. These issues highlight the need for a universal cable-and-plug that can improve accessibility and safety for EV charging at home and/or public charging infrastructure. To bridge the communication capabilities between different EVSE and EVs, the cable needed a facilitator board that could integrate communication between control pilot (CP) and proximity (PP) analog signals on older EVs and digital signals from newer smart EVSE. This board fits within a J3068 plug cable node and would include circuitry responsible for interpretation of either passive pulse-width modulation (PWM) or Local Interconnected Network (LIN) digital signals between EV and EVSE. Following testing with an EV emulator box, the charger displayed a successful connection to a smart station that used both PWM-CP and LIN-CP for communication between the EV and its EVSE. Through these new additions, these chargers are safer, more accessible, and optimized for charging at 3-phase AC or single-phase DC fast charging. Considering the outcome, adapting the cable for a higher voltage rating is the next target for the near future.