Electric power generation (8R 410 Tractor shown)
Overview
Electric power generation offers a different approach to tractor and implement sizing and equipment utilization. With 100 kW (134 hp) (480V AC) of electrical power available for traction assist via powered implement axles, the ability to pull wider or larger implements without a larger or heavier tractor is a reality. This technology is only available on John Deere 8 Series tractors equipped with the eAutoPowr™ transmission and optional electric power generation.
NOTE: The 100-kW (134-hp) electric power does not come on top of the power the diesel engine generates. The electric power needs to come out of the maximum engine power.
Component overview
Overview of components
- Power split stage
- First electric motor generator (MG1)
- Second electric motor generator (MG2)
- Input of the planetary gear sets
- Summing planetary gear
- “Lo” planetary gear set
- “Hi” planetary gear set
- Reverse gear stage
- Mode subassembly
- Dual inverter for MG1 and MG2,
- Dual Inverter for electric power generation
- Electric power generation power connectors (one standard from the factory, additional connector purchased through field attachments)
- Mechanical front-wheel drive
- Mechanical rear-wheel drive
Component locations
Location of components
- Cooling circuit
- Electric motor generators
- Power connectors
- eAutoPowr/electric variable transmission (EVT)
- Dual inverters
eAutoPowr and electric power generation components
Electric power generation utilizes power already being created through the electric motor generators (2) built into the eAutoPowr transmission (4). The electric motor generators then supply raw power to the inverter (5) and on through the power connector (3) located at the back of the tractor. An integrated cooling circuit (1) ensures smooth, consistent operation. Simply put, this system is like a diesel genset with a transmission that can supply power to the tractor drivetrain and generate power for implement use. In the future, this system could not only provide tractive power as it does today, but it also provides power to tractor auxiliaries similar to technology used and proven in construction.
Potential benefits of traction assist enabled by electric power generation:
- Primary and secondary tillage – Use wider implements on the same size tractor or with the same ballast level by powering implement axles to increase traction through tough conditions.
- Planting and seeding – Use wider implements via increased traction to handle challenging terrain with the same tractor and ballast or the same implement with a lighter tractor.
- Application – Use wider or larger capacity implements on the same size tractor or with the same ballast level by powering implement axles to increase traction through tough conditions.
- Harvest – Use larger capacity wagons on the same size tractor or a smaller tractor on the same capacity cart by powering implement axles to increase traction through tough conditions.
Traction assist with Joskin E-Drive
8R Tractor with electric power generation pulling a Joskin E-Drive slurry tanker
Joskin is the first company partnering with John Deere to leverage traction assist enabled through electric power generation. Traction assist provides improved traction by powering two axles of the Joskin slurry tanker, essentially turning a 4WD tractor into an 8WD application system.
Operating concept
CommandCenter™ display user interface for eAutoPower - Motor area
The drive system is very easy to use as it is fully integrated into the existing vehicle concept and does not require any additional operator panels. The operators can easily switch traction assist on or off in the CommandCenter display. The CommandCenter display also shows the operator the distribution of electrical energy between the tractor and external consumers.
Benefits of the traction assist
- Utilize the dead weight directly over two powered implement axles for increased traction.
- Allow for a potential reduction of 3600 kg (8,000 lb) of ballast or more, which would be required of a traditional tractor to complete the same task.
- Powered axles both increase traction and reduce field compaction from additional tractor
Slurry application with tine incorporator
The Joskin E-Drive system controlled by traction assist, with two axles electrically driven by one 100-kW (134-hp) electric motor, increases the overall traction by utilizing the unused weight of the implement during slurry injection with a tine incorporator. This feature enables contractors to operate relatively smaller hp tractors with up to 100 percent wider implement. The result is an increase of up to 45 percent productivity and a decrease of application cost of up to 25 percent per hectare, all while maintaining high soil quality.
Traction assist enables up to 45 percent higher productivity and 25 percent less cost per hectare
Slurry application in grasslands
Minimum wheel slip and highest crop protection are key in grassland applications
While injecting slurry into grasslands, high rates of slip can occur causing significant crop damage. Through the use of the Joskin E-Drive controlled by traction assist, operators experience increased traction by utilizing the weight of the implement over the two powered axles. This technology helps reduce crop damage caused by excessive tractor wheel slip. This results in increased yields and forage quality, while preventing potential replant cost.
High crop damage without traction assist
No crop damage with traction assist
A negative payload requires wheel weight without traction assist
No wheel weights required, even with negative payloads with traction assist
To learn more about the 8 Series Tractor electric power generation and Joskin E-Drive controlled by traction assist, view the following videos:
https://www.youtube.com/watch?v=kEj6_m5WtbQ
https://youtu.be/edhZn48RZJc
Components of the eAutoPowr/EVT and the Joskin E-Drive system controlled by traction assist
eAutoPowr/EVT and Joskin E-Drive components
- eAutoPowr/EVT transmission
- Dual inverter for MG1 and MG2 and dual inverter for electric power generation
- Electric power generation power connectors (one standard from the factory, additional connector purchased through field attachments)
- Future possibility: provide power to tractor auxiliaries
- Future possibility: second electric motor, such as for a pump
- 100-kW (134-hp) electric motor
- Gearbox
- Clutch
- Driveshaft for mechanical power transfer
- Axle differential cases
- First driven axle
- Second driven axle
- Mechanical power flow (blue)
- Electrical power flow (orange)
- Driven axles within the traction assist system
- Possibility to use wider incorporation tools for increased productivity
The theoretical maximum pulling force of the Joskin slurry tanker equipped with the E-Drive system controlled by traction assist is 45 kN (10,116.4 lbf). Under the assumption of a typical traction coefficient of 0,4, the electric motor supports the tractor with a power equivalent to 11,5 tonnes (25,353.2 lb) of additional ballast on the tractor. This additional ballasting weight of the tractor is not required when using the Joskin E-Drive system and can be saved.
Up to now, for the time-critical slurry application due to current restrictions, it was accepted to use relatively high wheel slip values of 8 to 12 percent to achieve optimum traction efficiency. The electric drive axles reduce these high wheel slip rates by up to 50 percent and thus dramatically increase the performance and efficiency of the entire system. In addition, the much lower tractor weight protects the soil from harmful compaction and ensures higher yields.
High-performance nutrient application – Value proposition
The reference system is a competitive tractor with 385.5 engine kW (517 engine hp) with an incorporator width of 6 m (19.7 ft) and an application speed of 11.5 km/h (7.15 mph), which reaches a real performance of 3.5 ha/h (8.65 acres/hr).
The John Deere 8R 410 Tractor with eAutoPowr system and Joskin E-Drive system with two driven axles and a 50 percent greater incorporator width of 9 m (29.5 ft), can achieve a 23 percent higher area performance at 4.3 ha/h (10.6 acres/hr), despite a reduction in the working speed to 9.5 km/h (5.9 mph).
If the width of the 8R 410 system doubles to 12 m (39.4 ft), productivity increases of 45 percent (5.1 ha/h [12.6 acres/hr]) are achieved, despite reduced speed to 8.5 km/h (5.3 mph). A system cost calculation, taking into account investment and operating costs, clearly shows that the cost of the procedure can be reduced by 15 percent and 25 percent respectively compared to the reference system, without taking into account the benefits of soil protection and higher yields.
The John Deere eAutoPowr/EVT gearbox impressively demonstrates the high potential of electrification solutions for machine combinations
Slurry application in strip-till applications
High-precision nutrient application is required for strip-till application
Poor traction during slurry injection with a strip-till injector is often experienced, resulting in less precise nutrient application, uneven gap rows, and a damaged seed bed. With the increased traction enabled through the Joskin E-Drive controlled by traction assist, operators can create perfect parallel rows and optimally apply nutrients in the seed bed. This allows for the best nutrient utilization, resulting in higher crop yields.
Damaged and low precise seed beds without traction assist
Perfect and precise seed beds with traction assist
Manure spreading with traction assist
Joskin, as John Deere’s partner for electric power offboarding, can implement the E-Drive system controlled by traction assist into their manure spreaders as well.
Spreading manure in hilly terrain traditionally requires the use of heavy rear wheels weights to counteract the weight distribution of the spreader, especially when the spreader is less than half full and driving upwards. The additional traction provided through traction assist, utilizing Joskin E-Drive, allows for a reduction in tractor rear wheel weight, reduces soil compaction and disturbance, and decreases slip and maintaining productivity.