Quote:
Originally posted by Serum
Artur, I thought you meant in the earlier post that a bigger airgap (Increasing) gave less eddy currents? (page three of this thread) I kind of lost you there to be honest..
Again, i don't think producers of BL motors use segmented magnets without a reason.... partial load is the reason.. (a-b repeat)
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If you review my post again, you will find out when and why air gap works.
(One-piece magnet to reduce losses – increase air gap, for segmented magnet losses are minimized that is why you can reduce air gap more. Cost more due to the high tolerances.)
Quote:
Originally posted by Serum
Problem is; heat is produced in the copper and in the magnets (electric magneticall lost?) the reason the magnets get heated is simple; everything with resistance produces heat, the speed of the electromagnetical field is higher than the speed of the magnet, (obvious) so it needs to absorb/compres something, with this absorbing/compressing is heat involved. reason for the copper to heat up is because of the resistance etc.
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Wrong for motor type we discuss. Both magnetic fields are synchronized.
Quote:
Originally posted by Serum
the magnet is used as a translator, to translate electro mechanical force into a rotating motion. I compare an audio transformer (as used in a tube amplifier) with this. It also works with electromagnetical forces, the packet of the transformer (E's and I's) normally are capable of producing a certain bandwith (limited in height (high frequencies), and due to statisfaction in depth (low frequencies) the thinner the E's and I's, the more efficient the transformer gets. And the faster it resonds to the electromagnetical 'signal' this translates in a higher achieved frequency (lets say 150khz instead of 30 khz)
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Every motor comes with inductive/capacitive/resistive ratings for phases. And based on them you can define what frequency response you get and what switching frequence to use and how efficiency will lay across
RPM range.
Artur
Threaded Mode
