Thanks for adjusting the quality level.
So it's easier for me to provide a positive contribution - I'll dare again :wink:
larsb said:
Why not just google the field strength and conditions needed to demagnetize a neodym magnet.
Google'ing the coercivity of Nd Magnets yields somewhere between 600 and 1200 kA/m.
For Sa-Co I found values as low as 80 kA/m
larsb said:
I bet it would take less time than writing the speculations.
Whats our field?
can still only speculate.
I remember a figure of some forty windings for a custom make, so 50 might be a reasonable order of magnitude.
People (larsb?) have reported 500 phase amps.
And we need some geometry factor (coil length?), for which I'd throw up 50 mm
200 A - 50 turns / 0,05m = 500 kA/m
So we are in the magnitude of Nd coercivity, and taking inhomogenous flux intoaccount, i still see a risk.
Loooks like I did'nt manage to shift the borderline of speculation that far :?
larsb said:
I calculated the extra torque that this motor could give in field weakening because of the reluctance in IPM design, it was very small. I consider it as a normal bldc in this regard.
But as i've got it, reluctance torque and field weakening are different concepts?
Maybe both are utilized by the same sihft of current phase angle, but a motor w/o reluctance can still use field weakening - OK?
The rotor image here
https://endless-sphere.com/forums/viewtopic.php?f=30&t=93627#p1376479
shows nearly no gap between magnets, which I have learned were relevant for reluctance torque, OK?
Anyway, I'll not dig into all details of motor design.
I just would like to program my controller so that I can get out the torque curve QS labelled "with flux weakening" in their ads .
Unfortunately, the Votol controller figures are not comprehensible in terms of physical meaning - at least not for me.
The best point to start with I found is this file
QSMOTOR SPEC for VECTOR Dirt Bike V1.2.pdf
https://endless-sphere.com/forums/download/file.php?id=251220
in this post
https://endless-sphere.com/forums/viewtopic.php?f=30&t=93627&start=175#p1461316
from QS Judy.