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Flipsky 4.12 Vesc in FOC mode?

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Jonny254
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Flipsky 4.12 Vesc in FOC mode?

Hi Everyone

I am running a longboard with a Flipsky  FSESC 4.12 50A SK8-ESC4 on a 6S setup (2x3S in series).

in the manual it says it is compatible with FOC.

i haven’t tried it as I am scared by the warning that vesc tool gives about 3rd party hardware.

Can anyone confirm that this vesc is fine in FOC mode?

Thanks a lot

Jon

jlcortex
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why not? 6S is very conservative for this ESC, I have run this ESC with FOC at 6S with not problems with default current limits.

I tested the VESC6 at 12S and 110A, someone told me not to think about trying it, not problem, works perfectly. 

I will test the Flipsky at 12S with FOC, i am sure it will work perfectly, for now I have not broken anything and I have done atrocities!

 

 

 

 

frank
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FOC on the 4.12 works best at low ERPM. In consequence low KV motors may work better than high KV ones (at a given voltage). Problems with FOC on 4.12 are often related to running the system close to the ERPM limit of the hardware design, while pushing a lot of Amps. For a 4.12HW 60K ERPM is about the limit. ERPM = RPM x pole pairs of the motor. The two shunt design of the 4.xx is not as good as a the 3 shunt design of the VESC 6. So any HW with two shunts is a bit limited FOC wise. The rotor can be tracked a lot more precise using 3 shunts. Precise rotor position tracking is essential for FOC operation.

Example: 200KV at 12 S (50V), 14 pole motor (7 pole pairs).    

200KV x 50V x 7pole pair = 70000 ERPM >> to much for 4.12

130KV x 50V x 7pole pairs = 45500 ERPM >> much better!

Just make sure you are in the lower ERPM area and don't push to many amps (use conservative settings like 35-40A motor max).

Jonny254
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Thanks for the infomative replies guys.

I am running at about 42000 erpm so I’m confident to try out the FOC.

It will be interesting to see what the effect of turning down the motor max current to 35-40A will have on performance. Currently this is set to 70A (manufacturer’s spec) but maybe I am never drawing that much when riding?

Jon