Good beginner background reading/videos and FAQ

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galstaf
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Good beginner background reading/videos and FAQ

Post by galstaf »

Hey all,
I have a decent understanding of power, voltage, amps etc. I am a MEng (but in materials and mechanical, not electrical).

So I get the basics of electrics and have built a few eBikes, and am ready to take on a bigger project. I would like to convert a twin engine boat and having checked around for the cost of motors etc, it seems that the power buy of the century is upcycling motors, chargers and controllers from decommissioned electric vehicles... 100kW motors with controllers for under $3K?! what what? :D

However this forum is a bit over my head and so am looking to get eased into it a bit more.
The FAQ is okish

https://openinverter.org/wiki/Inverter_ ... r_board.3F

but again throws you in at the deep end with talk of FOCs and VCUs and other such acronyms that currently mean not much to me.

Does anyone know of a good video series that shows the basics of taking and hacking an electric car and explaining how the control board works to control the the proprietary inverter/motor controller. Something that after watching, the regular forum posts won't be as mystifying to me.

I know enough to be dangerous, but would like some of the gaps filled in. Any suggestions would be sincerely appreciated!!

Cheers
Gal
MattsAwesomeStuff
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Re: Good beginner background reading/videos and FAQ

Post by MattsAwesomeStuff »

Generally it's hard to find that info, because the people who could write it, don't need to read it. So there's not a lot of discussion about it.

The forums are generally higher level troubleshooting and questions and detailed technical discussions that go over most people's heads. Bit of a curse of open source projects.

Cheapest bang for your buck are probably still salvaged hybrid motors. Not the most powerful, but they're quite literally being thrown away. It's common to see whole assemblies being picked up for $150-$300.

If your goals are higher end performance, then you probably want a Leaf or a Tesla motor, and to pay a lot for it.

For the Prius inverters, both Damien (gen3) and Johannes (gen2) have pretty much plug-n-play drop in solutions. Rip the control board out, shove the replacement board in onto the same mounting screws, do a little configuration dance with known-working parameters, and you're good to go. You could use these with the properly mated transaxles, or on any other motor you'd like. You could spin a leaf motor with a prius inverter if you felt like it.

VCU isn't something I've really seen someone show off or explain well in a finished project. I think the idea is that you'd run it on a touchscreen and it acts like a replacement to the brain that used to run the car, only you get to hook your own things up to it. I'm not sure what it's supposed to look like, what features it's supposed to have, why you'd use that instead of, I dunno, not using it or doing something else. (I'm not saying those answers don't exist, just that I don't know them). Most of the conversation around it jumps straight into the technical parts of how, because that's the real challenge. I think the current big VCU project is supposed to be as general as possible, you can configure it in a modular way for any vehicle, not just a specific vehicle it's designed for? Again, the details of what the project actually is aiming for and how far it's progressed to that goal are murky for me.

There's 2 basic ways to spin an AC motor, depending on the type of motor. I think one type has an encoder, the other type has a resolver? One type works on induction motors, the other on permanent magnet motors? Something like that. Anyway, you need to use the correct motor control software to spin the type of motor you've chosen. FOC is one of those, SINE is the other.

Batteries are going to be the expensive part of any budget build.
arber333
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Re: Good beginner background reading/videos and FAQ

Post by arber333 »

I for the most part am not a video generation. I cant decypher relavant data from video screen. I need to read about it and make notes.
I guess in the meantime rest of humanity have evolved so much that now we need to post videos for them to stay interested at all.
I am sure you can find much engineering information in wiki (besides the forum) if you motivate yourself enough to read through.
OTOH you can still watch Damiens videos where you can find tons of info on various options.
https://www.youtube.com/user/pooey1911

Or Johannes posted some very interesting videos with engineering data...
https://www.youtube.com/channel/UCNnQO1 ... 8ybbs7hltQ
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