New hybrid powertrain developed by the CNH Steyr brand
Any Formula 1 fan will be accustomed to seeing its high-performance cars harvesting unused energy and deploying it as a tactical power boost along the track.
Farmers could be doing something very similar in the field soon, as Austrian tractor manufacturer Steyr unveiled its first fully operational hybrid tractor at a recent press conference in Austria.
The company debuted the hybrid tractor concept at the Agritechnica show in 2019 and was scheduled to unveil the hybrid transmission design at the next event in 2021 before the pandemic forced its cancellation.
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Now ready for production, the Steyr Hybrid CVT is based on the company’s 180-hp 6175 Impuls CVT, which has a hydromechanical continuously variable transmission in the rear half of the drivetrain.
This is combined with a hybrid electric module on the front axle, increasing the maximum permanently available horsepower of the tractor to 260 hp in a very light and nimble frame.
The hybrid system itself consists of an electric generator and an electric motor. The jar also contains a bank of supercapacitors that store energy that would otherwise be wasted for later use.
The power generated by the hybrid system can then be combined with the conventional hydraulic drive on demand via the intelligent all-wheel drive clutch.
Steyer says there are many advantages offered by hybrid technology, the first of which is E-CVT.
This can only propel the tractor using the hybrid electric system, drawing about 75 kW of engine power at 1,100 rpm, with the rest routed to a PTO-driven implement.
During operation requiring inconsistent power loads, the E-CVT results in a smoother, more comfortable ride, and significant fuel savings.
The E-Shuttling system provides smoother, more responsive directional shifting, with high torque instantly available from the electric motor at low engine speeds.
This means less dwell time and 41% increased maneuvering speed, again providing a 15% fuel saving while the loader is in operation, the company says.
Having instant torque is useful in the field and on the road, as E-Boost helps bring the tractor up to speed when pulling away from intersections or after slowing down at roundabouts with a heavy towing load.
When going downhill, electronic braking technology helps maintain a constant speed and uses the electric motor like a retarder in a truck, reducing brake wear and increasing safety.
The electronic power steering system uses power to accelerate the front axle when cornering in the field, reducing the turning radius by 15% and increasing maneuvering speed by 20%.
When four-wheel drive is engaged, E-Torque Vectoring directs torque to the front or rear wheels when needed, which means improved traction by running the axles at the same speed instead of running the front axles 3-5% faster.
Saving fuel, reducing tire wear and reducing soil and crop damage are advantages, as well as the ability to use four-wheel drive on the road without the risk of damage or rough driving.
Speed variation in the field when planting through difficult patches can also be reduced by 6% using electronic torque fill, increasing work rates, while E-Eco mode combines electric and CVT during light work to use as little fuel as possible.
The Hybrid CVT can supply up to 75 kW at 700 V via a standard AEF outlet to power tools, powering their various functions and the wheels of the trailer axles, for example.
Steyr did not provide a specific date for the start of commercial production but hopes to have it available before Agritechnica 2025.
Although development and pre-production models carry the Steyr branding, the technology is fully transferable, and other brands in the CNH group are likely to offer hybrids as well. It is also scalable to higher horsepower machines.
When asked if the technology will become the norm, Steyr’s Markus Butz said he believes it is likely to be a popular choice among current buyers of higher-spec, high-end tractors.
“The technology is flexible and there is potential for fuel savings if you stabilize the engine speed at a point you can’t achieve with a conventional transmission.
“We will also see more and more electric implements and we think the combination (with a hybrid tractor) could work well,” he concludes.