Bldc tricks/tuning ?

Anyone still playing with trap wave? Had a go at it today on my new batch dv6 pro. All seems good, vesc doesn’t spit faults like my d75 did. The noise is cool but it doesn’t seem like it has as much torque as foc.

Any setting in particular I can play with?

@Tony_Stark complains of the opposite :thinking:

Never played with bldc, but can say that the Radium prototype boards running bldc have way more torque than any other board i’ve ridden.

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Yes interestingly I tried out FOC for the first time on a Radium board yesterday and was very disappointed in the performance. It felt very underwhelming and “mushy” compared to the instant neck snapping torque and 2 stroke powerband I’m used to with BLDC.

I’d love to know if anyone has tips to improve acceleration with FOC mode. Other than the obvious “reduce ramping time” which I always run at 0.0

For BLDC optimisation, I suggest to try the following changes:

In general > advanced tab at the bottom you can increase hall sensor extra samples to 5 (this option is removed on most recent firmware)

Under BLDC > advanced tab increase minimum switching frequency to 5khz for smoother feeling startup

In BLDC > general you will notice a big difference from increasing startup boost. I’m only running 0.02 but you can go higher like 0.05 at your own risk.

I believe there are other parameters to get further performance from it but I’d like to build a dyno and have a spare controller on hand before toying with those.

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Killer info thanks man :metal: I’ve still got my ramping at .3… been hesitant to lower that too much after my accidental throttle flip to broken wrist trick I pulled last year. I’ll give those other settings a go for sure tomorrow though.

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Beware you may not have flawless standing starts in BLDC. I tried it and wasnt sold at all. It does make a nice sound though.

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Surprisingly man, it actually feels a bit smoother on my setup. I mean I only did a couple starts with it but it seemed good.

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Yeah nice. Maybe it was my shitty UboxV2.

Maybe time to re-visit now I’m running DV6s

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I have been running a fsesc 4.12 on 13s for a while now.

Is bldc mode saving me? Will it die if I switch to foc ,?

13S and FOC would definitely be great encouragement for a 4.12 to die. And in my experience they certainly don’t need encouragement

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This is a requirement for me and why I will never run bldc full time

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Why i abandoned it too. No good for race starts with the setup i was running.

I know Radium Performance has had success on BLDC with DV6s though.

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Looking at the time it takes to hit duty slow maybe it is just as quick, just smoother.

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Legit the only reason I run FOC instead of BLDC (trapezoidal) is because of HFI.

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I would beware though, using the ESC in a way that isn’t the most popular way, while it may suit your needs better, also would seem to increase your attack surface for finding firmware bugs. If the folks developing the software aren’t testing BLDC (they probably aren’t at all) then you may want to ease into it.

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I hear ya, seems to work the other way lately… more development more problems.

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If you used something like Ackmaniac 3.103 for your BLDC I would almost guarantee you won’t find any bugs.

Hope you don’t plan to use any modern peripherals though.

Peripherals?

All the UART stuff

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Ah ok safe there then, only have a bt module which I only use for checking battery level and temps.

Can definitely notice the increase in punch and response but it seemed soon as the motor temps got up around 75 degrees I started getting the issues with launching from a dig.

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I would argue the other way. Since BLDC is never touched it has always just worked on every firmware version I’ve tried. FOC however has changed and even been broken by firmware updates numerous times.

BLDC also produces smaller current spikes and is far less likely to trigger ABS overcurrent in my experience. With much less to go wrong one of the main reasons I use BLDC is for safety.

Also the trick to getting better starts in BLDC is high kv. With more rpm the sensored portion is much shorter before it kicks into sensorless at full power. Extra hall sensor samples and tuning the sensored to sensorless transition rpm helps with starts as well.

I don’t find it too difficult to give the board a little shove and roll onto the throttle as the board switches to sensorless to ensure a good start. Doing it that way still feels way faster than just punching it in FOC and being underwhelmed with the acceleration.

Its possible that FOC is not running optimally for me though because it does feel pretty tame at 150 motor amps.

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