Field weakening is awesome- testers needed

Anyone else knows what would happen?
Or have I overlooked a serious answer?
@Lee_Wright maybe? :pray:
or @Lee_Wright perhaps. :laughing:

1 Like

99% duty cycle works, and you should get some speed increase.

But test it before riding because maybe you should tweak D axis scaling option under foc > advanced (to much and it acts like field weakening, as it gives more D axis current). Just dont set both options to same value if you are not on latest beta fw.

3 Likes

You would probably notice the controller loses track of the motor and sends current the wrong way at the wrong time, making you faceplant

2 Likes

What does that mean? Some random acceleration or braking?

1 Like

It uses the 5% duty off time to determine the rotor position from the bemf so if you shorten it to 1% it may be more likely to lose track of the rotor.

4 Likes

Found this on youtube from Vitali.
It was for dual hub motor with enertion vescx 1.2 and he had no issues whilst riding :man_shrugging:

1 Like

Min duty cycle option is only used in BLDC control, so no efect in foc as duty cycle depends on speed.
It does effect current measurement like you said, but only on low speed.

Also default min is 0.5% not 5%, but max min value is 10%, limited in fw.

2 Likes

Yes but default max is 95% which means default duty off is 5%, in other words 5% of the time the rotor position is being analyzed. Increasing the default max reduces the % time the controller uses to determine rotor position.

3 Likes

Imagine those roller coasters with accelerator pads on the track. Each accelerator thingy represents one pulse in the right direction. Now imagine one of them is spinning at full speed in the opposite way. You’d have roller coaster seat shaped ribs for a while after that.
Same with vesc because with only 3 wires and 6 pulse stages there’s like 5 wrong ones that can lock the motor up.
Just, test it on the bench, put load on, variate speed, but don’t ride it until you’re sure and don’t recommend it to others as safe. It’s only 4% more speed

2 Likes

Anyone gone full out on the street with this yet?

2 Likes

someone in europe/canada should do this because they have free healthcare

12 Likes

Will someone please film a vesc during a battery disconnect test? Spin up a motor, switch off the battery. Will the mosfets explode from rectifying 100-120V bemf? That’s what I want to know.

2 Likes

you’re asking someone to intentionally break their vesc?

5 Likes

Give me a vesc and I’ll do it

6 Likes

use one of those 30$ flipsky ones

3 Likes

Link?

3 Likes

will try to find it again. they come up occaisionly for that price on aliexpress

1 Like

send me one, i will do the test on bench :joy:
jk, no plz dont

2 Likes

Sheesh I paid full price for a fsesc4.12, would hate to buy 2 more for that price.

1 Like

i aint paying

3 Likes