teklektik wrote:At some point, sales may ramp up, but you certainly must realize that there is no proprietary technology involved in producing this motor. If it garners a respectable market share and there is money to be made, imitators will arise without difficulty. I would think that you would like to achieve as much product visibility, market penetration, and customer support/loyalty as soon as possible. That means aggressively enabling sales, not a vague plan of word-of-mouth tales by customers. You shot yourself in the foot when you released information of another (possibly better) commuter motor (also with no specs), which further clouded the picture and undoubtedly killed some sales of this motor.
Hey teklektik, nice post which I feel was pretty much spot on. Anywone who thinks they've nailed some secret motor sauce in a BLDC hub motor is generally out of touch with basic physics, and/or they are driven by hype and marketing rather than engineering and facts. Having now done a bit more background reading on the various post histories related to this hub I see there is a lot more of the former going on than the latter.
Anyways, on to this post:
accountant wrote:Once more time ;
It is about using different materials, not about the windings.
Cromotor is different than 2X NC, it just looks simmilar from outside, and that are all simmilarities.
From all I can tell you are making claims that the stator laminations are done with a different grade of silicon steel. Sure there many types of steel, with various resistivites, different hysteresis losses, different permeabilities, and slight variations in the saturation point. The effects of different permeability is fairly insignificant given the air gap present in field path. However, reducing the hysteresis losses can have a noticeable effect on the no-load "cogging" torque of the motor, making it spin more freely unassisted and also giving a higher peak efficiency at low power levels.
Similarly, higher resistivity and/or thinner laminations will reduce the eddie current losses which come into play at high RPMs. Both of these parameters would be accurately included in the model from item b) that I asked for, which is the no-load current draw at two different supply voltages. From the slope of that line we can deduce fairly well what the internal motor losses from eddie currents and hysteresis are like at any RPM. Your special material included.
However, neither of these things have much effect on the high power/ high torque side of the performance curve, where the behaviour is dominated almost entirely by the I^2R copper losses. And so even if I didn't both to model the steel and used just the 9C characteristics, the simulations at high power levels which is what most people here seem interested in would be pretty much the same. If you think I'm wrong and you have something really special going on with the hub, I'm all ears...