thunderstorm80
1 kW
- Joined
- Mar 29, 2016
- Messages
- 383
Hi,
As I understand, in a DC brushless motor, at each instant 2/3 coils (A & B) are being energized while the third rests. (One attracts the magnets, the second repels (but both create force in the same direction) , and the third rests)
This is very easy to understand on a Wye connection: The third coil is effectively terminated from it's "C" phase wire as it's conroller's MOSFET is cut-off so no current flows through it.
I also understand that since the same current has to flow through two coils, it is effectively a series connection with lower current but double back-EMF - and is equivalent
to a lower kV motor. Am I right? (the one which is often call a "torquey" motor wind)
What I don't understand is how a Delta connection can work:
If the controller wants to energize only two coils, and I would assume the voltage would be introduced via two phase wires only at a time, then still all 3 windings would still be energized - albeit at a different voltages¤ts: The coil which directly "see" that voltage would be (let's call it "fully") energized, while the two others would still have current in them - but via a series route - meaning half the current and quarter the power.
I assume I am wrong here, so I would be happy to get some professional answers...
Thank you
As I understand, in a DC brushless motor, at each instant 2/3 coils (A & B) are being energized while the third rests. (One attracts the magnets, the second repels (but both create force in the same direction) , and the third rests)
This is very easy to understand on a Wye connection: The third coil is effectively terminated from it's "C" phase wire as it's conroller's MOSFET is cut-off so no current flows through it.
I also understand that since the same current has to flow through two coils, it is effectively a series connection with lower current but double back-EMF - and is equivalent
to a lower kV motor. Am I right? (the one which is often call a "torquey" motor wind)
What I don't understand is how a Delta connection can work:
If the controller wants to energize only two coils, and I would assume the voltage would be introduced via two phase wires only at a time, then still all 3 windings would still be energized - albeit at a different voltages¤ts: The coil which directly "see" that voltage would be (let's call it "fully") energized, while the two others would still have current in them - but via a series route - meaning half the current and quarter the power.
I assume I am wrong here, so I would be happy to get some professional answers...
Thank you
