Select FOC on the Motor tab, then Hybrid on the BLDC tab.
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Just off the top of my headâŚa short board cruiser built for carves & people slalom, not high speed, would definitely benefit from sensored FOC.
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Thatâs not hybrid mode. Thatâs going to use FOC and completely ignore your BLDC settings. Hybrid mode means hybrid between sensored BLDC and unsensored BLDC mode. I was under the impression @cliofreak is using BLDC mode, not FOC?
Doesnât matter if you are using FOC or BLDC. After takeoff, sensors should be switched off. Thereâs no benefit from the sensors after that. All it does is waste energy and produce extra heat. âSensored FOCâ in that sense doesnât even exist. Itâs always sensorless or hybrid, unless you set the switching frequency so high, that it doesnât happen. But thatâs would be a pretty bad idea.
Motor settings â Motor type â BLDC and Motor settings â BLDC â Sensor Mode â Hybrid
Iâm not gonna argue with you, but your wrong. Maybe do a few build then come back either some experience.
I just pulled that out off the top of my head, thanks for looking it up.
Sensor mode for BLDC:
Sensorless ERPM for FOC (always enabled, no switching to âpure sensored FOC modeâ):
Ok Iâm confusedâŚ
So Iâm running FOC. Can I have FOC hybrid as a thing!? I canât stand the coggy, noisey BLDC.
Ah, I see! When I read about your heat issue I thought you you might be running sensored BLDC, which would explain the problem. If youâre running FOC then sensored is fine. As I said: FOC has no pure sensored mode like BLDC. It always uses unsensored above the âSensorless ERPM for FOCâ value (unless you changed the default settings) similar to hybrid BLDC. So this is not the problem.
Your cut-outs will probably be solved once you fix your battery. But itâs still weird that your motor gets this hot. Maybe post your settings or try the motor detection again. You have a big motor. Maybe you have to increase the current for the detection. Also probably removing the belt for the detection makes it more accurate.
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Ive a new BMS and cells coming Tues hopefully. Iâll know more when that batt is fixed!
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Cool! Post some updates how it goes. Good luck, man!
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OK, so I replace the bad pack (What a nightmare⌠itâd be easier starting from scratch.) Good news is that its now charging to 100% and Iâve got 42V. I checked the BMS and I think its fine. I thing the error was that there was a break in one of the nickle strips. If a pack dies again, Iâll know that its the BMS for sure.
So bad news⌠Im getting a real stutter and shut off on the motor when I try to apply any torque from start off. If I gently take off or push start and gradually climb speed its ok and when its up and running (15mph +) I can hold throttle down fully but from slow speeds its useless. This setup used to have a savage torque. Itâd launch off the line very strongly (10s4p, 15T42T gearing).
With the bad pack I was topping out at 21mph. Now Im hitting 28mph.
So, any ideas why I canât apply torque at very low speeds!?
I did a mile loop of a park: https://metr.at/r/Q2oPc
SETTINGS:
Sensored FOC switches to unsensored at 2500 ERPM, which is something like 1-2 mph for you, so literally as soon as you are barely rolling. If you everything runs fine after you kick once it is probably a sensor problem. You can try doing the FOC sensor detection again, but it sure looks like you did it already. You have a big motor, so you should make sure that the motor easily spins during hall sensor detection. Maybe try to set the current for detection to 10 or 15 A instead of 5. Removing the belt wonât hurt either.
If that doesnât fix it, you could test unsensored FOC. Iâm not familiar with that app, whatâs that? Metr? It doesnât say in your screenshots which is FOC sensor mode but it should be where it says âSensor mode: Hallâ, not âhybridâ. The hybrid one must be BLDC sensor mode. Anyway, if unsensored FOC improves your startup there is definitely something wrong with your sensors.
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Yeah, I think its time to try BLDC at least just to try out a different mode. Its not really a 1-2 mile an hour issue. Itâll start in FOC no probs but only if I feather the throttle up to 15mph or so. I used to be able to slam on the throttle with exactly the same setup. However, throttle slamming, or indeed even half throttle chokes it up and kinda cuts out/stutters.
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OK, then itâs not a sensor thing. This sounds like something went wrong with the motor detection. Try re-doing it for BLDC and FOC. No belts. Increase the current for detection to 10 or 15 A, see if you get the same results as for 5 A.
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Late to the discussion, but did you check that the phase wires have a solid connection? My friend had the same problem, and when he got up to speed, the vibrations at that exact moment made one of the phases stutter, and when he then stopped, there was no problem (unless he wiggled the wires) 
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Hey, yeah this could be the issue but it seems to happen only on full load. Ive had stuttering motors in the past due to bad connections. This seems different.
Just getting around to setting this up again. Ive tried to set it up in FOC and it seems to go OK but then has the same stutter issue when I try to accelerate hard. However, when I try BLDC mode, it fails on the hall sensor test (bad detection). It also fails when I remove the hall sensor cable and select âno hall sensorsâ. It spins up ok etc but fails and judders at the end of the short test. Bad motor!? Its an Alien Power System motor. 6374 200kv
up the duty cycle slowly up to 0.10 and see if it detect. low kv want more voltage for detection
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So, I upped the duty cycle (even though Ive never had to do that before with this same setup) and it did detect hall sensors on BLDC mode (at 0.09 D). This mean BLDC works ok.
So, I tried to get FOC running again. I did the same thing and when detecting and setting up in VESC Tool, I ran it at 0.05 Duty first and it all went green as usual but when riding it it stutters an cuts off when accellerating hard from zero mph. I redid the VESC TOOL at 0.09 D in FOC mode and it made no difference. ??? Im lost.
Hall Sensors appear to be working but in FOC mode it stutters on full acceleration from zero mpg. I even checked the belt to see if it was slipping. Thats the kinda feeling it has but its not slipping (as its ok in BLDC mode). Any other thoughts please!?