Electronics > Projects, Designs, and Technical Stuff
pinout puzzle on big BLDC drivers (repurposed automotive motors)
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
[0] Message Index
[*] Previous page
Go to full version