Change combustion engine by electric motor

[exael]

hello engineers,
Do you know or have experience changing a combustion engine for an electric motor in heavy machinery such as tractors?
In the engineering office for which I work supervising production, they will take an unexpected turn and this is for me new, I wanted to know about your comments. Thanks.

 

[LittleInch]

The speed and torque curves will be potentially quite different.

Equally the cooling issues are quite different.

Electric motors would tend to prefer maybe constant speed operation compared to variable speed from a combustion engine.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[BrianPetersen]

This isn't just a motor swap. No experience with tractors but the automotive experience has found it best to fully redesign the vehicle around the characteristics of EV powertrains.

 

[LittleInch]

If the power system is a hydraulic drive then it might work better than a manual geared transmission.

If you need to go backwards and forwards, this might also be more difficult.

How is power delivered? - Battery or OH powerline.

Those massive earth moving trucks in some of the mines work by a diesel electric drive where the power sometimes gets delivered by OH power lines during the heavy lift haul road up from the base of the quarry.

But just swapping it out into a gearbox type drive is going to be difficult.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[TugboatEng]

Engines are typically structural to the tractor. This will make any such conversion quite difficult.

 

[exael]

Based on the comments, then the possible heavy machinery to replace the engine would be trucks that are used to transport 300-400 tons of stones at a constant speed and less than 15 mph.

 

[Jboggs]

I am assuming that you are not a native English speaker. Your comments are a little difficult to understand. If I understand your question correctly, I would give this answer: you cannot simply pull out a combustion engine and replace it with an electric motor. That is true on any equipment. That is the main reason it has taken auto manufacturers so long to offer electric versions of their vehicles. It requires a LOT of engineering. So much engineering and re-design that it would be easier and cheaper to replace an entire vehicle than to convert it from combustion to electric.

 

[GregLocock]

Building an electric tractor is feasible, powering it is difficult because a tractor spends hours at a time at full throttle, especially when ploughing or subsoiling, and so it needs big batteries (or external power).

Your idea of a low speed truck sounds much easier, and they are widely available

https://electrek.co/2022/10/18/ayro-vanish-utility-lsv-electric-mini-truck/

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[gtaw]

Ok, so I'm not alone in wondering if I understand the inquiry. I though he was trying to replace an electric motor with an IC engine.

Best regards - Al

 

[exael]

I am so sorry, I want replace IC engine by electric motor

 

[MintJulep]

In the engineering office for which I work supervising production, they will take an unexpected turn and this is for me new

Should we guess that the company you work for currently manufacturers tractors with gasoline or diesel engines and has decided to manufacture electric tractors?

In this thread thread1528-364721 there is some good discussion about converting road cars to electric. Including some photos of Eng-Tips member "moltenmetal"'s hobby conversion of a Triumph Spitfire.

 

[rb1957]

ok, fair enough ... post deleted ...

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

 

[TheTick]

Electric motors would tend to prefer maybe constant speed operation compared to variable speed from a combustion engine.

Really? I understand the opposite to be true. Especially for diesel.

 

[LittleInch]

The tick,

electric motors at a fixed frequency are fixed speed. Varying speed can be done, but takes up energy and adds cost. EV motors appear to use variable frequency drives to alter speed.

Diesel engines are most efficient at a certain fixed speeds, but can vary speed much more easily (your right foot).

Any system has efficiency curves - you just need to find out what it is.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[EdStainless]

Will there be a continuous external source of power? Such as overhead lines?
If not then you are likely in trouble.
The energy per mass for batteries is about 45x that of diesel fuel.
This is why many mine/quarry trucks are diesel electric.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[TheTick]

Respectfully, that seems a very narrow view of how electric motors operate and are controlled. There are other ways to control motors, and there are certainly many other types of motors.

AC motors have a peak speed tied to their frequency and poles. But they can and do go slower, and find a point where the torque-speed curve matches the torque they are driving. Additionally, the torque vs power curve changes with voltage.

DC motors also respond to changes in voltage. They respond even better to PWM.

 

[GregLocock]

EV motors are electronically commutated multiphase variable frequency.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[TheTick]

Good point. Add variable frequency to the list of control options.

 

[CWB1]

Not sure what info you're looking for but there have been many electric "tractors" over the past century ranging from LeTourneau mining equipment to the GE Electrak riding mower to various BEV and hybrid machines today. Different machines have different requirements but the biggest difficulty with offroad EVs is power density and component durability. Throw enough money and time at most any problem tho and it can be overcome, its just another engineering exercise.

 

[TheTick]

I worked on electrifying Jacobsen turf mowers in the 1990s. Some of the electric tractor patents in our knowledge portfolio dated to the 1930s.