Dynamic Charge System Verified in Application under Various Road Conditions 2023-01-0705

The electric vehicle (EV) is one means of realizing carbon neutrality for automobiles, but at present, EVs still faces a number of issues. The main issues include, for example, (1) cruising range, (2) installed battery capacity, (3) charging time, (4) infrastructure facilities, and (5) support for Heavy-duty commercial vehicles. Full electrification of heavy-duty trucks, in particular, requires high power output. This means that enormous installed battery capacity is necessary, and as a result, cruising range on a par with engine-driven vehicles cannot be readily achieved.

Therefore a dynamic charge system was devised here that would provide electric power to EVs directly from the infrastructure so that EVs could undergo intermittent charging while driving. This is a conductive charging system that operates from the side of the vehicle (roadside), and research has been underway on the application of this approach to passenger cars and race cars. Attention was further directed to resolving issues with freight vehicles, which account for most of the CO₂ emissions in the transportation sector. The system was applied to a heavy-duty truck (4×2 tractor, 45-ton class), which up to now had not been readily convertible to an EV, and the results were reported at WCX 2022.

The present report will describe further support for heavy-duty vehicles by expanded application to a 6×4 tractor (60-ton class). To support use under various road conditions, the equipment was installed in a curved portion and on uphill and downhill sections, and the report will present results from verification with actual vehicles during dynamic charging.

The results include the following:

• The vehicle weight of the 6×4 tractor came out at 930 kg (about 10%) lighter than the diesel engine-powered truck that was the base vehicle.
• The minimum capacity of the batteries installed in the vehicle came out at 100 kWh, which is about 10% of that in an EV truck that charges while parked.
• The charging power was a maximum of 450 kW on the curved road portion, the uphill grade portion, and the downhill grade portion, and the viability of dynamic charging and its control was successfully verified at vehicle speeds from extremely low up to the legal limit of 80 km/h.