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Diesel / Electric Locomotive Technology

2640 Views 75 Replies 13 Participants Last post by  SeattleTrainGuy
I wish to follow the technology of the diesel / electric locomotive, as I have a 1983 Isuzu P/U with a 58hp, 4 cyl diesel engine, that I would like to have power one of my 10kw generator heads, with a 120v or 240v electric motor powering my rear axle.

My intention is to remove the 5-speed manual transmission and put one of my 10kw generator heads in its place, then idle the engine at the RPM necessary to achieve 60Hz, and direct-wire the A/C 120 or 240V drive motor to the generator head to supply power to the motor.

It doesn't make sense to me to spends thousands of dollars on batteries, along with adding the extra weight, then having to recharge the batteries, when I already have a complete power source.

If anyone knows where I should be searching, please point me in that direction? Thanks!
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Very good. Thank you. I'm interested to learn all I can here.
If it makes you feel any better, I've wondered about doing the same thing for my Jeep. Do all the EV motor stuff I want to do, then put a lawn mower engine in it to generate the electricity. In my case I'd want to go to batteries eventually, but this setup would get the electric motor portion done, and meanwhile I'd be getting 50+ mpg. I know pretty much the same about this stuff that you do.

Definitely following this, to see how things go and whatnot.
Without a battery, the entire system just replaces the transmission with an electro-mechanical transmission system which is continuously variable (which is nice) but much less efficient than any conventional automotive transmission... and that doesn't make much sense.
OK, probably a really stupid thought here, but I'm pretty sure if this was the case, trains would use massive versions on automotive transmissions. Forget for a minute the 10kw Harbor Freight piece--assuming you got one that actually had a reasonable output, then it would adjust for how much power was actually being USED by the system. I suspect brian_ would want one battery at least, to help with regen braking, and also so that the power has somewhere to go when you're sitting at a stoplight not using much/any power.

With the generator setup you can set the load such that the engine is in whatever torque peak (most efficient points in an engine's power curve--lower ones in the rpm band generally take less gas and usually make a little less power) it needs to be to make adequate power, and will be most efficient at WOT, so if you can get it to run at like 1200 RPMs and WOT, and make enough power for your needs, then it should run well and get like 50 mpg (assuming you have an engine that is a good size for the application). Additionally, if you put that much load on it, it should require little to no cooling, as it won't be losing much energy as heat when you lug it that much.
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Mechanics do maintenance (change lubricants, etc), diagnose the location of faults, and replace faulty components. Just as the mechanic who services a car has no idea how anything inside any of the car's electronic components work (but can replace a failed ECU), the train mechanic probably has no ability to design or even functionally describe the control systems of a locomotive. Maybe you'll find one who has a personal interest in the technology...
OK, so how DOES the ECU work? I'm not going to say you're wrong that they probably don't know--I'm much the same way with cars. But really it's just a motherboard (a bunch of wires organized on a green board, effectively), with some transistors and maybe a couple of transformers and such right? I mean it's just a computer...if anything goes wrong it's a broken wire or component?
If you're already getting 44 mpg and refuse to add even a small battery (could you somehow use a 12V Li-ion and a step-down for it????? Seems unlikely but I guess you probably could), it sounds like you're really not going to gain anything with the swap, except maybe some low-end torque (which, being a diesel and a 2600 lb truck, shouldn't be an issue anyway).
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I guess I have no idea where you're getting these numbers. With the 5-speed you ought to be able to short-shift it and keep it in a similar RPM range, and thus get similar mileage. At that point it all comes down to your foot and shifting.

It being a diesel, you shouldn't be pulling a ton of RPMs anyway right? And because of all of the low-end torque of the diesel you should be able to shift it at like 1800-2000 right? And either way it's going to be idling at stop lights and such, so I would think it would be a wash, or it would be LESS efficient if anything, if it's stuck around 1800.

And as @brian_ (thanks for your patience!) said, if you refuse to use ANY batteries, then the RPMs are going to be all over the place, and frankly will have to be stalled at stop lights and such, correct? Which is good from a fuel perspective, but diesels don't like being shut off and then fired right back up again, correct?
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