FOC mode setup issues

Hi guys!

I’ve been playing around with setting op FOC mode this morning but for some reason I can’t get it to run smoothly. Having issues with startup cogging of the motor. I’ve done all that jazz measuring the resistance, inductance and flux linkage in VESC tool. Also played with the settings for Openloop mode, but can’t get it to start properly.

Setup is: Aerodrive 6374 192kv motor (Sensorless) Maytech 50A VESC (FW:3.38 HW: 410) 10S3P li-ion pack

Any ideas on how to fix this? The reason why I want to use FOC mode is that it would make the board a bit more silent.

ok so foc is great for if you’re running sensored motors on either a vesc 6 or focbox. running a vesc 4.2 on foc unsensored will most definitely blow up your speed controller. it’s just too hard on the components. use bldc and don’t set battery amps over 40a. motor amps you can push to 70a i think

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Cogging is normal for unsensored. Change to sensored to get rid of the Cogging. Or push to start.

This is a pretty broad statement. There are loads of people running 4.12’s on foc without issue.

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Did you do motor detection without the belt on?

when i say this i mean stock where there is no cooling and no heat sink

It’s actually pretty well known that 4.12 without direct FET’s will blow on FOC.

Cogging will occur in both BLDC and FOC settings modes if you are running and sensorless motor.

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Not a great idea foc with normal vesc 4.12 and maytech definitely don’t like it.

The scream of a sk3 motor is a beautiful noise

I would be checking the type of battery before telling someone to set the max battery amps. ie; if thats a 10s3p from diye or a chinese prebuilt then the bms will go poof at 40 amps.

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@dareno (i assumed he’d know the Max draw of the pack)

Built the pack myself, VTC6 cells and a 60A Battery Supports BMS. Should be fine. Have been running it at 50A battery settings.

What is exactly the issue then? Why does it blow up the FET’s? Also I did think the cogging should be solved with running it open loop to start with (weird name, as the FOC should also run open loop seeing as I’m not using a hall sensor, encoder. Or is the current and voltage measurement of the stator done properly enough with some added observer to derive RPM from that data?)

Didn’t do the detection without the belt. It would be slightly of but not significantly it seems. Even saw Benjamin do these measurements with the belt still attached.

And yes the sound of the SK3 really does sound futuristic. I also like it. But want to be a bit more stealthy. :slight_smile: