The H2 refueling process is monitored to assure a safe charge and full tank as indicated by the State of Charge (SoC), in the shortest period. The communication between the Hydrogen Refueling System (HRS) and vehicle is unilateral, from vehicle to HRS defined by SAE J2799. The SAE J2601 standard is sub divided into a Table-base Protocol, also named a Static refueling control and a Formula Protocol, also named a Dynamic refueling control. The latter one, assures quicker and a higher SoC refueling. The actual HRS market infrastructure uses two types of H2 gas pressures, 35 and 70MPa. Light-Duty Vehicles (LDVs) are mainly served with the 70MPa to increase the H2 mass stored on a vehicle. Typically, 2 to 3 tanks are integrated in a vehicle. The HRS protocol validation methodology consists of doing regular refueling’s with the few Original Equipment Manufacturer (OEM) vehicles in the market. Moreover, the station software is validated in a non-refueling environment. Therefore, it fails the simulation of the safety triggering scenarios of a real refueling event. This can result in safety gaps when in a real refueling these scenarios occur, resulting in potentially hazardous conditions. The study is focused on the potential of the communications of the vehicle to partially validate the station. The aim is to replace the vehicle communications side to simulate boundary case scenarios where the station should also stop. This shall be done by replacing the infrared generator of the vehicle with a dedicated one that will send a customized message from a computer with the test cases loaded. Thanks to this simple but effective approach, the validation of 30% of the ANSI HGV 4.3 (test methods for hydrogen fueling parameter evaluation) which defines all test scenarios to validate HRS fueling protocol SAE J2601. The simulation tool covers basically the vehicle communication with the HRS. The performance and functional integrity of the HRS itself is not included into the scope of this study. In a later stage, a rig with tanks and sensors will be built to access the HRS as well. The simulation protocol lay-out is an innovative approach to quickly assess the communication integrity between vehicle and HRS. The project has required the development of tools and devices capable of reading and sending messages in the communications protocol SAE J2799. Furthermore, for validating the protocol, a virtual refueling simulator has been developed, to execute the communications part physically, requiring an Infra-Red (IR) transmitter and an IR receiver. This virtual HRS enables the creation of extra custom test cases, as an added value. Moreover, it has also helped validate the final product in a virtual environment, before testing it in a real refueling. The results obtained in the present study can offer to the HRS industry the ability to simulate safety triggering scenarios in real refueling. This will ensure that station will be capable of responding to potentially hazard scenarios afterwards in real case events and solve the safety uncertainty created by current validation methods. KEYWORDS: H2 – HRS – Connectivity – Protocol simulation

Mr. Johan Bruyninx, Project manager, IDIADA