Could use some advice on paralleling two controllers.

Voltron

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I have a couple of matched low power controllers sitting around, so going to try the paralleling thing on them for the experience, and could use some tips before letting the smoke out. So I have the phase wires are Y-ed out to go to both, and on the Halls, the three signal wires are Y-ed, with the red and black coming off of one controller. So the big question is does the black/red not get wired into the other controller at all, or does the black get hooked up too? In other words, does the second controller just need the signal input from the Halls? And will it basically be the same for the throttle wires?

Thx ahead of time...
 
This sounds like a great way to smoke two controllers...

No idea on how to do the wiring for this, though. Pull out some circuit diagrams for a similar controller and find out?
 
No, it's been done, and works. And there's not too much smoke in these controllers to begin with anyway, so it's not going to be too sad if they go up...
 
so you have 6 phase wires from the motor ? and 2 sets of hall sensors in the motor ?

edit or 3 phase wires from motor and 1 set of halls
 
No, not the 6 phase set up like the Hubmonster with 2 controllers each feeding separate offset 3 phase pairs....but rather 2 controllers feeding the same 3 phase and sharing the Hall sensors...
 
I have never seen this in a working setup and have my doubts if it will work reliably or even work at all .. but the black wires would need to be connected together but only use one 5v supply from just one controller..
 
Supposedly it works, as long as the Halls are getting the 5v from one controller, or slight differences between the 5v output for each controller means they will fight to regulate each other... and again, these are such cheap controllers that even if it goes badly will be worth it for the learning experience.
 
In wonder whether the controllers are consistent enough in their internal resistance to adequately share the load.
 
I can answer for the throttle, yes so long as you only power from one controller it will work fine. Done that lots. Halls SHOULD be the same. But I've never tried it.

It should work on hub motors, they have fairly low commutation speeds so you shouldn't have sync issues.

In any case is love to see the results!
 
So how did this work out, anyway?

Been a lot of discussion about paralleled controllers, but not much for actual testing and results.
 
Voltron said:
It didn't work at all, at least on the controllers I used, even with only one powering the Halls and throttle.

Can you tell us what happened?
Motor will not spin up, extreme stuttering, overheating, or controller(s) go pop?

Asking because I am interested in trying this myself, albeit with 2 identical controllers purchased from the same manufacturing batch.
Hoping they would be closely enough matched to make this work.
 
It wouldn't spin up... But I put very little time into pursuing it, as other projects beckoned, and so many cheap high power controller are available now, but most of the feedback from some weighty ESers was that unless you link them at the brain chip level it prob wasnt going to happen.
 
Ok cool, thanks for the feedback. Shame it did not work out, but I have a theory.

When you connect both controllers to the same 3 phases and halls, and apply the throttle, both controllers are going to try and start off on whichever phase the MCU chooses. This results in 2 phases receiving power at the same time, thus they fight one another.
Basically, the motor is not going to spin up, but rather stall in place.

So just like you mentioned, the controllers would need to be tied together at the processor level if there is any chance of this working.

AH! But what if you were to spin the motor up and then apply the throttle? This would give the controllers a chance to see feedback from the halls and fire the corresponding phases. Riding along peddling, get some RPMs going in the motor, then apply throttle....
maybe that would be enough to get the controllers in sync without needing to mess with joining at the MCU level?

(This would seem to be more sensible for hub motors. It might be more difficult to try with a mid-drive with a clutch/freewheel.)
 
I enjoy "armchair engineering" as much as everyone else here, but...the only way to truly see what will happen is to give it a shot. Take pics, and post the results.
 
Years ago, I split the throttle out-put and ran two KU63 controllers. I placed the controllers close to each other and kept the common ground short to reduce feedback looping. There was some degradation of throttle "feel" but eventually I went to two throttles(left half twist next to a left thumb), which IMO is the best set-up for 2WD short of an involved system using adjustable power deferential. The fact is, no 2WD needs to have both wheels under power all the time. W/my 2WD, the rea motor is the main motor and I use the frt. approx. 25% of the time. Accordingly, my frt. batt. pack is 25% the size of the main pack.
One way to run two controllers off one throttle is to use a Cycle Analyst to run the second controller.
 
Were you running the phases to two different motors? That I could see working... But with both controllers to one motor, my gut feeling is that as soon as there's the slightest imbalance in the timing, today's better fault protected controllers see it as a short in the phases and shut down.
 
No, I have one of those Cyclone 3kw mid-drive kits.

Plan was to buy a couple of those cheapo Sunwin controllers (preferably the 12fet), and experiment with them. As cheap as those are, I am not sure if they have much of any protection.
Spinningmagnets is right though... can't prove/disprove my particular theory unless I actually try it.

Edit: Sorry, I thought that question was aimed at me. Motomech's comment did not show up on my end until after I posted. :roll:
 
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