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Re: 1600/1800w Brushless DC Motor (my1020 clone)

Posted: Thu Nov 29, 2018 9:38 pm
by Brian
I think the smoothness of the data here is all measurement noise. The T20 looks better because it's a nicer scope, measured at a higher frequency , and spinning faster so the noise is a smaller percentage. Plus I just realized I screwed up my data analysis and the T20 data is artificially quantized in the time domain; that doesn't affect the results but makes the graph look more regular.

I think the difference in harmonic orders is driven by the physical construction of the motors (number of magnets and coils basically). However, I don't have a real explanation for how these numbers come to be from these motors, so that's a lot of guessing.

I don't have a good intuition for how the harmonics affect the efficiency with any commutation scheme (working on it). Roughly speaking a controller expecting a sinusoidal motor will be fairly happy with the BOMA/MY1020 but less happy with a T20.

Re: 1600/1800w Brushless DC Motor (my1020 clone)

Posted: Mon Dec 10, 2018 3:53 pm
by Jason
Interesting. Okay, just trying to wrap my head around what we can determine from this information between each motor.