Electronics > Projects, Designs, and Technical Stuff
pinout puzzle on big BLDC drivers (repurposed automotive motors)
<< < (4/4)
mtraven:

--- Quote ---The measured phase resistance of the coils means nothing.
--- End quote ---
well shit that's a useful piece of information.  Would measuring the inductance be of any use to me?


--- Quote ---A EPAS system in order to provide the maximum fidelity must provide torque assistance to the driver.....
--- End quote ---
while I very much appreciate your detailed explanation, all I was really trying to say was the column mounted, wormgear style assist systems get away with a smaller motor because of the huge reduction in a worm gear.  I just didn't want people to think it was one of those smaller ones.  and that is enough on that.


--- Quote ---You won't get any info from Hella regarding the driver IC, as that is a proprietry automotive chipset, so you'd have to sign an NDA with them before they will release it to you.
--- End quote ---
I didn't even ask for a schematic, just a pinout and what the pins were expecting...but they didn't even bother send a "no" ...seems a bit unprofessional if ya ask me.


--- Quote ---Realistically, peak motor currents of around 100 amps are used, perhaps as high as 150 amps for a few seconds, but the resistance of a lead acid battery starts to become limiting, ie the supply voltage falls with increasing current, limiting the power you can pull from the battery to a couple of kW at peak.
--- End quote ---
so based on that, how much current should my mosfets be rated for? 150? 200?

your comment about a limited supply from a battery got me thinking, what the hell kind of power supply and I gonna need to run this thing.  I made a spot welder a few years back that supplies 1200-1500amps, but that's just a few seconds..thats going to need some serious consideration.

On a related note, I have just learned one of the methods for controlling speed (maybe the only?) is to regulate the supply voltage feeding the mosfets.  Do I have that right?  So that is another big ass mosfet(or set of mosfets) correct?  I had just assumed the gates of the Fets would be driven by a variable input that would determine speed.  I am sure there is a reason they don't do it that way, any idea what that reason is?




james_s:
Something I forgot to mention, there is an open source firmware called BLHeli, and another one the name of which escapes me. Those and the associated hardware notes are a treasure trove of information on driving BLDC motors.
oPossum:

--- Quote from: james_s on December 02, 2019, 04:41:21 am ---Something I forgot to mention, there is an open source firmware called BLHeli, and another one the name of which escapes me. Those and the associated hardware notes are a treasure trove of information on driving BLDC motors.

--- End quote ---

SimonK is one of the others. I think they both are derived from an earlier firmware.

edit: Derived from Bernhard Konze's tp-18a firmware

There is also the more comprehensive VESC firmware (unrelated to the previous).
Navigation
Message Index
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod