Doesn’t the core material also dictate saturation point for a given frequency? I forget how that works but I thought as your frequency increases you need to go to higher permeability materials; ferrite saturates at much higher frequencies, however is much more fragile to the kind of abuse we see with our motors physically, in addition, I think the frequencies it tends to shine in may be beyond all but the highest switching speed (high ERPM) motors, and even so, we aren’t talking MHz range here, so kind of moot. There is however advantage (up to some point I am unfamiliar with) in how thin the steel laminations are in hobby motors; competition/high performance multirotor outrunners (28mm and below) are running as thin as 0.12mm laminations last I checked. Only a few motors in the 63xxx size I know of that run 0.2mm lams, and those in theory will saturate their iron stacks at much higher frequencies. Not sure if this also affects magnetic saturation as well. I might be using the wrong terms; as the lamination thickness gets thinner I kind of imagine it’s like the magnetic inductance decreases…?
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