IEEE Electrification Magazine - June 2014 - 38

John Deere E-Premium Tractor-
Electric Drives in Agricultural Machinery

Figure 10. The JDES family of Class B PD 550 Inverter Deere and
original equipment manufacturer (OEM) applications.

diesel mower. the 7500 e-cut hybrid mower engine can be
throttled down to save fuel, which is significant during the
cutting season. in addition, throttling the engine down has
the added benefit of significantly reducing noise. the reel
speed always stays constant and steady for a consistently
ideal clipping frequency. the 7500 e-cut hybrid mowers
always look pleasing to the eye and play evenly as well.
these mowers are easier for technicians to maintain than
the conventional models due to use of maintenance-free
brushless electric motors, no hydraulic lines in the reel circuit, and all of the standard benefits of hybrid mowers, such
as quick-adjust cutting units and white-box diagnostics.
switching to hybrid technology is a breeze, with little to no
learning curve for the operator. enriching the customer experience is the key to the adoption of the hybrid technology
deployed on the turf-care vehicle platforms. the 8500 e-cut
hybrid mower is shown in Figure 12, and publicly known
information about e-cut hybrid mowers can be accessed
using the Web sites listed in the "For Further reading" section.

Figure 11. The JDES family of Class B PD 300 inverter for Deere
and OEM applications.

I E E E E l e c t r i f i c ati o n M agaz ine / j un e 2014

the increase in the need for agricultural equipment
caused by the increasing world population is more than
obvious. the current agricultural equipment has reached
its optimization limits in terms of complexity and efficiency with the current technology. Furthermore, improvements in the area of drive technology, mainly mechanical
or hydraulic drives, are currently limited. therefore, the
focus in this area will be on electric drives for heavy-duty
off-highway applications.
vehicles in agricultural applications currently use 14 v of
electricity just for onboard use. introduced at the 2007 agritechnica Fair, a high-voltage system was added to an agricultural vehicle, the John Deere e Premium tractor. this new
system provides power to the electrically driven engine auxiliaries. in addition to that, the intelligent control of the auxiliary drives helps to reduce the fuel consumption of the vehicle,
especially under part load conditions, by just driving the
auxiliaries at the actual required power level. the e Premium
tractors represent the first high-power electrification
approach in a series production within agriculture and
already represent a catalyst for further electrification in agricultural equipment.
the main drivers for the usage of higher voltage on
agricultural machines are
xx
optimized controllability of power flows across agricultural machines and between machines
xx
generated sufficient electrical power
xx
reduced parasitic loads caused by engine auxiliaries to
improve complete machine efficiency
xx
increased flexibility in arrangement of components
xx
increased productivity and operator comfort.
the areas of electrification using higher voltages can
be divided into four groups:
xx
engine auxiliaries
xx
traction drives
xx
energy storage for electric drives
xx
farm-implemented electrification.
the main focus will be on drives or functions requiring
high power, such as the engine radiator fan, the air conditioner (a/c) compressor, the air brake compressor, and the
alternator. the major benefits are improved performance,
productivity, efficiency, and flexibility in the component
arrangement. the indirect benefits for tractors are
1) the possibility of power increase
2) enhanced boost power curve
3) improved transport acceleration that enhances productivity
4) increased load response in field power take off (Pto) work
5) lower fuel consumption
6) improved comfort (electric driven a/c compressor).
the design criteria that affect almost all engine auxiliaries are
1) space requirements
2) mobile environment capability

Table of Contents for the Digital Edition of IEEE Electrification Magazine - June 2014