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What I want to achieve is: Drive the motor forward while the floating phases generates energy (P=U*I) and recover said energy.
When you say "Synchronizing to the rotor angle is still necessary." I'm still not sure what you mean exactly, do you mean other/better than the synchronizing already...
You mean like mr. debrajdeb is proposing here https://www.microchip.com/forums/FindPost/431639 ? Except not switching all 3 lower mosfet's but merely the floating phase(s) i.e. the phases that are not energized?
What do you mean by "resolver", something more precise at lower speeds than hall...
In post #15 I give reasoning to Mr. Kajunbee.
Next question, out of ignorance; Would it be possible to filter the terminal voltage, so that only the bemf remains, and would the linkage between circuitry after the filter and coil still remain intact? E.g. if you draw a current after the filter...
That is correct, as I have informed you on a previous occasion, I'm reluctant to disclose the main objective because then this thread would be filled with posts informing me that my undertaking is impossible.
Could you please elaborate on that, I don't quite understand what you mean.
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Yes indeed, but what would be the point though? I mean other than quantifying the bemf voltage?
I wanted to use the bemf for regenerative braking, but since the bemf is lower (I checked by spinning it around by hand) than Vcc it will require additional circuitry.
Here is the scope shot of phase A (probe across A and Neutral/Virtual ground) it resembles the scope shot of the delta configuration although a bit clearer
That would still require some serious signal processing to get something useful out of that. I'm surprised it's still such a gang bang of...
You may be confusing BEMF with FLYBACK, here is a thread that addresses the misappropriate use of the terms BLDC: Once and for all EMF, BEMF, CEMF or Flyback?
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Yes I see that now, in the beginning the delta was chosen for some reasons that made sense then, but let me try...
Gents,
These days I'm trying to identify my BEMF (BEMF=voltage induced in the coil by the moving magnetic field) in my BLDC system, but I can't seem to find it, maybe you can help me?
This is the circuit diagram for your kind reference
This is the scope shot of phase A
ch3 control signal...
As I said; you are correct. It doesn't make any difference. You have convinced me, it was a very silly idea from my side to begin with and I was wasting everybody's time, I'm sorry about that.
On popular demand, I have now thrown the circuit board and BLDC on the scrap heap, as we speak...
Klaus, in a three phase BLDC only one phase is energized at any given time. But let's say you are right about everything, I have no problem with that, the energy flow is always zero, I stand corrected, case closed.
But I said that you have already explained it very clearly in theoretical terms and that I agree with you. (It's not you, it's me that is "incorrect" ;-)
Nope. The experiment was simplified and conducted in a way so that the same physical coil was used i.e: Disconnect BLDC completely, connect...
My dear Klaus, first of all, you know that I value your opinion, and I don't want to antagonize anyone, if my post is doing so, then I would kindly request you to delete it, I don't mind.
Secondly, I'm in agreement with your theory, it is all logical and coherent.
That is a brilliant...
I was under the impression that the flyback current was trapped in the upper half of the bridge, so I wanted to set it free. I don't know if I did a complete behavior analysis, there seems to be diverging opinions, I can't really judge, so I thought an experiment was called for.
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