Experimental Hybrid

Electric cars, trucks, ATVs, NEVs - things bigger than a motorcycle.
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Solar DH   100 µW

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Experimental Hybrid

Post by Solar DH » Dec 16 2016 6:13pm

Thanks all for this forum. A little experiment I have been working on for years:

https://youtu.be/9z9b6AC46Nc


Progress was slow until I got the jackshaft idea from building ebikes. Probably breaking all kinds of rules but I am learning a lot. Made a new end plate for the motor, and rewired it to isolate ground and enable reversing. I’ll post the bike builds next. 1st post so apologies if I am embedding wrong.
I garage tested it with a ebike controller at 24v. I then drove around the block by connecting it directly to the pack, starting off in first and putting it in neutral while hitting the contactor. It sagged under 16V at over 750A at one point, but lived. The motor is a direct drive series wound, and the Bosch stall spec is 730A. Any reason I can't rewind this motor into a sepex and run it at 48v?

[moderator edit to fix link] thank you!
Last edited by Solar DH on Apr 06 2018 11:37pm, edited 3 times in total.

Punx0r   100 GW

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Re: Diesel Starter Motor PHEV

Post by Punx0r » Dec 17 2016 9:28am

It's basically a 1HP motor (and an inefficient one at that, so lots of heat) no matter how you wind it, you'll just make the current more manageable if you're using cheap, readily-available controllers.

I admire your ingenuity but can't see how this is a practical idea...

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amberwolf   100 GW

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Re: Build 0.0: '84 VW Rabbit Diesel Starter Motor PHEV

Post by amberwolf » Dec 17 2016 2:18pm

Solar DH wrote: It sagged under 16V at over 750A at one point, but lived. The motor is a direct drive series wound, and the Bosch stall spec is 700A. Any reason I can't rewind this motor into a sepex and run it at 48v?
It's only meant to run for very short periods (seconds) with very long (hours) cooling time between them.

I suppose if you force-cool it with air thru it, it might run for a while as a continuous motor, but you'd be a lot better off finding some other continuous-duty motor to use, like forklift motors (some of which will already be sepex if that's the kind of controller you've already got for it).


Another consideration is the RPM of the motor--you don't want to spin any brushed faster than it was designed for (max rated RPM on the plate), or the commutator can explode--the copper segments detach and fly off, possibly destroying the rest of the motor in the process as it jams things up and stops it's rotation in a real hurry. If they are travelling fast enough to exit the motor casing itself, they can also damage other things inside the compartment the motor is in, or even exit that compartment if the walls are thin enough depending on the material.

"Severe unscheduled self-disassembly" is the phrase I usually think of whenever I read of this happening to someone doing an EV conversion without planning for that. (usually when they use a series-wound motor with no load on it during testing, at a higher voltage than it was originally used at)

Punx0r   100 GW

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Re: Build 0.0: '84 VW Rabbit Diesel Starter Motor PHEV

Post by Punx0r » Dec 17 2016 3:07pm

They also usually have bronze bushings instead of ball or roller bearings. As you say, AW, not meant to operate for any significant time (either at any one time or total over the car's lifetime).

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