Yes, I've seen what you're talking about too, but believe it or not, it is an artifact not purely of the motors, but of how we drive them. One of the causes it is actually torque ripple, which is a combination of cogging torque and specific flux harmonics. This is accentuated by the trapezoidal commutation methodology used in most of our ESCs, as well as some harmonic interference between the ESC drive frequency and the commutation rate. BLHeli_32 solves some of that by making the drive frequency adjustable, so you can move it out of the range where it causes harmonic interference, and it also uses a slightly tweaked commutation method. I think more gains are possible given some looks at alternative commutation methods like sinusiodal or FOC, or maybe some sort of hybrid. There's a lot of stuff that goes in to the dynamics between motor and ESC and we have a lot of room for growth still.
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- Unapproved
quadmcfly:
Sep 19, 2017 at 08:48 AM
Yes, I've seen what you're talking about too, but believe it or not, it is an artifact not purely of the motors, but of how we drive them. One of the causes it is actually torque ripple, which is a combination of cogging torque and specific flux harmonics. This is accentuated by the trapezoidal commutation methodology used in most of our ESCs, as well as some harmonic interference between the ESC drive frequency and the commutation rate. BLHeli_32 solves some of that by making the drive frequency adjustable, so you can move it out of the range where it causes harmonic interference, and it also uses a slightly tweaked commutation method. I think more gains are possible given some looks at alternative commutation methods like sinusiodal or FOC, or maybe some sort of hybrid. There's a lot of stuff that goes in to the dynamics between motor and ESC and we have a lot of room for growth still.