Aside from displaying new, market-ready machines, some manufacturers again used Germany’s Agritechnica machinery show to provide a glimpse into the engineering future. Tractors and equipment designed to use high-voltage electricity to power implement drives instead of traditional PTO or hydraulic systems have been appearing at the event since 2009. There were more concept machines advancing that technology on display again this year.
But because this is an emerging technology in agricultural equipment, electric drive standards for implements have still not been firmly established. When John Deere introduced its two market-ready 6RE tractor models at the 2011 show, they were designed to supply 480 volt power.
The Agricultural Industry Electronics Foundation (AEF), which is made up of engineering representatives from most manufacturers with a stake in electrical technology development, has been working to develop standards so the industry can really begin to move forward on the high-voltage drive front. “The idea behind this is that the electric motors on all standard attached machines should be compatible with every model of tractor, and the only limitation should be the output data of the tractor engine,” reads the AEF’s official explanation of the project.
Once standards have been set, we’re likely to see more manufacturers release market-ready, electric-drive equipment — or at least introduce concept machines. So far, however, AEF has not officially announced it has established a standard agreed to by all the major manufacturers.
Despite that, AGCO’s Fendt brand jumped into the electric drive arena this year, debuting its “X Concept” tractor at Agritechnica. Still only a concept machine, the Fendt comes equipped with a 700 volt DC implement drive outlet on the rear.
It is now widely expected that 700 volt DC power is likely to become the standard.
Powered by a 200 horsepower diesel engine, the X Concept tractor is capable of supplying 130 kilowatts of power to an implement.
“This is a research study,” said Benno Pichlmaier, a Fendt engineer, about the X Concept. “It’s only for advanced engineering. It will not go into production in the next years. We are looking at what are the concepts of the future. We’re looking to have a discussion with the implement manufacturers, because the tractor alone will not improve with the electrical system.”
Engineers at Fendt have been working to develop durable electrical systems that could be used in future tractors if high-voltage implement drive becomes mainstream.
“The generator itself, has been totally newly developed for agriculture,” Pichlmaier continued. “In 2001 we started a research project called MELA. In German it stands for mobile electric power drives. So we tried to bring that technology to mobile machinery. If you buy a standard electric motor it will not survive in our (agricultural) environment. The result is now the shape and the technical functionality of that (tractor’s) generator.”
With the tractor engine revving at 1,600 r.p.m., the newly-designed generator reaches peak output capacity to power systems on an implement.
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So far, Fendt is focusing on providing only high-voltage current through a standard rear outlet. However, it is possible that the tractor, if it ever sees production, could have additional lower voltage outlets capable of running typical electrical equipment like power tools, which is a feature John Deere initially included on the first electric drive-capable tractors it introduced at the 2009 Agritechnica show.
“Our strategy is to have one output, which is DC,” said Pichlmaier. “Currently we are focusing on the tractor-implement electrification, not so much to allow welding or drilling or something. It’s in discussion what (other) possibilities there are, because some contractors would be interested in connecting power tools in the field, and so on. But it’s also a legal issue, because, for example, in Germany it’s required to ground the system, which makes it a little more complicated to provide that.”
A little way down the aisle at another exhibit, Rauch, a German company, displayed its high-voltage concept machine: a three-point hitch mounted fertilizer spreader.
“There are a lot of tractor manufacturers out there working on electric drive systems,” said Michael Linz, from Rauch’s electronic development division. “Currently, we are 100 per cent compatible to the John Deere tractors, the 6RE. Our systems (on the spreader) consist of two direct drive electric motors. We expect the tractor system (to provide the) generator and inverter.”
The spreader is capable of taking power from an outlet that delivers 130 kilowatts of current, but it only requires 20 to power it. “In the industry there will be implements that need more (than 20 kilowatts),” Linz said. “We have decided, as an industry, to have a common connector.”
The current cost of motors and components for high-voltage drives in agricultural applications is quite high, due to the unique requirements and low volume demand. “Here we have a functional concept,” explained Linz. “However, right now we have quite an issue with the cost of components.”
In time, however, that cost premium compared to standard PTO or hydraulic drive systems will likely disappear when production numbers increase. And high-voltage drives offer benefits other systems can’t match, particularly lower power demands that reduce operating costs.
“If you compare the electric fertilizer spreader to the hydraulic one, we have about a 10 per cent increase in efficiency, which leads to reduced fuel consumption in the tractor,” he continued. “We see, also, improvements in the distribution of the fertilizer. We need quite exact disc speed. We can get that with electric drive.”
Linz believes electric drive for implements will become the dominant system in the future. “The only question is, how long will it take,” he said.
Scott Garvey is machinery editor for Grainews. Contact him at [email protected]