TEST, SAFETY & SYSTEMS
RADICAL REGEN The development of a more efficient regenerative
electronic braking system is poised to provide enhanced brake management for electric trucks
R
egenerative braking is the process used by an electric vehicle (EV) to regain kinetic energy that would otherwise
be lost during braking. This energy is instead returned to the car’s battery as electricity so it can be used to replenish range. These small boosts in battery range can accumulate and improve efficiency over time when used regularly. Now, Tier 1 supplier ZF’s Commercial
Vehicle Solutions (CVS) and EV manufacturer Tevva have teamed up to develop an enhanced regenerative braking system for the latter’s 7.5 tonne zero-emission battery electric trucks.
THE TEVVA HGV BEV The trucks are based on Tevva’s own
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hydrogen fuel-cell range extension technology, and uses a blend of regenerative and compressed air brakes to add an extra layer of safety and responsiveness for drivers. Asher Bennett, Founder and CEO, explains: “For normal short distance operation, the truck will run as a normal BEV vehicle, with the energy to the motor being delivered solely from the battery. For longer trips, as the battery state of charge becomes low and/or when power demand is high, the hydrogen fuel cell will start up and supplement the battery with initially 25kW and up to 50kW of additional power. For high gradient and heavy load operation where the power demand is high, fuel cell and battery can feed the motor in parallel to ensure that the required
power is always available.” The Tevva BEV has been developed
with several key design considerations that Bennett says differ from most other HGV BEVs on the market. “We have a twin motor and twin inverter system which allows for optimisation of motor power supply to ensure that the power can be delivered in the most efficient way at all times. It also allows for ‘limp home’ in the event of a single motor or single inverter failure,” he continues. “The switched reluctance motors have no rare earth metals which further enhances the environmental credentials of Tevva vehicles. Thirdly, the battery chemistry is Lithium Iron Phosphate which ensures great long-term durability as well as good thermal stability. Lastly, the unique Tevva exterior design sets the vehicle
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