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Sensorless Startup Motor Cogging

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Swinde12
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Sensorless Startup Motor Cogging

I was wondering if BLDC mode or FOC mode is better for motor startup in terms of least cogging and most torque. Which settings can be tweaked (in either mode) to reduce the cogging on startup and increase torque. 

Thanks

e-nduro
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Joined: 2018-11-25 20:05
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In my opinion BLDC has better startup because you can set the initial duty cycle and then higher torque. While FOC seems to have some soft-start ramp.

And despite the advanced setting for injecting "Id" current it does not seem to provide the same start torque (actually it is not Id until the observer is not working)

Maybe Benjamin could clarify this topic.

In my experience FOC is also a bit dangerous at startup, I blowed up two VESCs (4) doing tests on the dyno (with high inertia), while with BLDC I never had any accident

Swinde12
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Last seen: 10 months 1 week ago
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I'll play around with BLDC and the initial duty cycle. I'm running VESC 6 so hopefully they aren't as prone to blowing in FOC mode. 

Thanks!

Caden