Determined to lead the charge toward zero-emissions freight and urban logistics, British electric truck maker Tevva has been working to ease the burden of carbon reductions on fleet operators. In January, it began production of its battery-powered medium-duty electric truck, for which it also plans to offer a hydrogen fuel cell range extender. For now, it's extending range a simpler way, improving its regenerative braking system so that it's four times more efficient than it was previously.
Tevva worked with German Tier 1 automotive supplier ZF to greatly improve upon the regenerative braking system that's a cornerstone of its TEV75 medium-duty electric truck. The companies adapted ZF's electronic braking system (EBS) for use with Tevva's combined regen and compressed-air braking system. The EBS electronically splits the driver's brake input into a blend of conventional air-powered friction braking and electric-motor regen braking that delivers improved response and safety, more balanced braking, and reduced wear and tear on components.
"When the brake pedal is pushed, most of the 'braking' is handled by regen, meaning that the drive system slows the vehicle down," explained Tevva's lead drive and brake systems engineer Uzair Jilani. "The conventional braking system is still needed to bring the truck to a complete stop, but this double layer of safety is an excellent aid to more efficient driving. It also means that the hardware undergoes less strain to extend the braking system's life in the long run."
Now that most of the braking is under the domain of regeneration, the system is able to safely output up to 180 kW back to the battery. Prior to the addition of the ZF EBS hardware, it was only able to safely regenerate at rates up to 40 kW, via the passive regeneration from the air braking system. This improvement promises to deliver more power back to the battery during driving, thereby actively increasing range per charge.
As for exactly how much mileage the system adds to the total range, Tevva doesn't provide an estimate. It advertises a 140-mile (227-km) total range for the TEV75 truck, which comes equipped with a 105-kWh battery pack.
Tevva engineers worked carefully to make the braking system compliant with ZF's stringent approval criteria. As part of the process, it tuned its vehicle control unit (VCU) for better integration and compatibility with the ZF EBS.
Tevva's 140-mile all-electric truck is in production now, and the company will next add the 7.5-t hydrogen-electric model, more than doubling the range of the BEV version for up to 354 miles (570 km).
