Electric Transmission?

[npalen]

 

[5030]

Knowing how expensive big Deeres are to maintain, I bet it will be as well and of course i keeping with JD's no right to repair attitude, probably won't be any repair manuals printed except for dealers.

 

[npalen]

I found interesting the 100KW built in generator part of the system. I am curious, however, at what voltage and AC or DC? The Deere PTO driven generator that is used to power their electric drive planter meters is some odd like 56 volts.

Interesting is that they are promoting the 100KW to power an auxiliary device such as a trailer behind the tractor. Makes me wonder what "they" have up their sleeve and what the future holds.

Edit: Seems like the system would have to be fairly high voltage otherwise taking humongous size cables to transmit 100KW to an external device?

 

[npalen]

Lugged tires on tillage implements driven by the 100KW generator? Would require less tractor weight resulting in less compaction by utilizing weight of the implement to supplement the tractive force? I don't know, just kind of interesting I guess.

 

[stevem5215]

1st step in direction of Battery powered John Deere's. After all there are diesel generator Locomotives in use for a gazillion years now. Why not a tractor ?

 

[Vigo327]

The Deere eAutoPowr transmission utilizes two high-power electric machines, instead of the conventional hydrostatic unit, to achieve the required gear ratio. One electric machine is coupled to the engine and the other is coupled to the summing planetaries to deliver infinitely-adjustable wheel speeds.

Toyota invented this for the Prius 25 years ago, and most other hybrid cars have copied it on some level. If you use 2 motors as inputs to a planetary gearset (which usually have 1 input, 1 'held/braked' element and 1 output) and vary the speeds of those two inputs you get an infinitely variable gear ratio from a very small number of parts.

It's brilliant. It changed the world! But it's no longer new. Maybe new to tractors.

The 1997 Prius:

 

[npalen]

A demo of the Prius transmission.

 

[npalen]

1st step in direction of Battery powered John Deere's. After all there are diesel generator Locomotives in use for a gazillion years now. Why not a tractor ?

The Caterpillar D7E is a "diesel generator locomotive".

 

[npalen]

Agricultural implements with powered axles are already successfully used in Europe to help push the tractor from behind while working in the field. "EVT technology offboards electricity from the tractor to provide added power to the implement and can reduce wheel slip, improve up-hill performance, and enables the tractor to pull wide implements without the need for extra ballast or a larger tractor," Jardon said.

The above is an excerpt from this:

John Deere offers new Electric Variable Transmission

John Deere is offering a new stepless Electric Variable Transmission (EVT) that enables precise speed control and enhanced drivability.

www.deere.com

Feel like I'm talking to myself here but that's okay as long as I don't start answering myself!

 

[Vigo327]

I have a PTO-driven 3pt trencher I was using today. Only the chain bar is pto-driven, but it also requires hydraulic hookups! It has a hydraulic motor and a driven wheel axle. The reason is that you leave your tractor in neutral and use the hydraulically driven axle to give you a finely-variable low-low-low gear creep speed so your tractor only moves as fast as it trenches. You can set it to move one inch per minute if you want to. So you're no longer really tied to 'gears'.

With electric drive you can also do the same torque in forward and reverse so any time you have a modern electric drive you also have electric braking, so that's nice.