VESC or ESC for new build

II built my first foilassist “box on board” with the 6384, Foildrive 3blade, 12S3P and a Kontronik Kosmik 200HV as ESC.

The ESC is in the aluminium box attached to the battery box - so no extra cooling needed… It works perfectly - I can foil for about 30 minutes at full speed in efoil mode. The reason for using a “normal” ESC was because “godfather Oliver” from beenee said it was “better” - he talked about the disadvantages of BLCDmode emulation in VESC (if I understood correctly). Now I’m moving on to my second build (everything in the board) and I’m wondering if I should use a VESC or stay with the ESC… What are the advantages and disadvantages of VESC vs. ESC? And what is this FOC mode in VESC?
Thanks a lot!

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Great combination you have!
My friend used Kontronik till it burned. It felt stronger than other esc from some reason. It has a capability to tune itself to the motor. The downside is the price, yes…

Sure reasons to use vesc are: a. Receivers aceepts it’s telemetry b.Tunability
About efficiency - that is an important subject that nobody made me sure - TODO test in the future.

As far as I have read on the forum, people struggle to use VESC in FOC.
Therefore the choice lies between duty cycle and current control.
Duty cycle is similar to esc.
So the only potential improvement can be in current control. Expected gain - less waisted current comparing to ESC.

Let me give a short excursion into FOC (fiel oriented control). As the name implies this control algorithm is based on controlling the electromagnetic field inside a motor. There is some quite complex mathematics behind - at least when comparing to the available processing power on conventional motor controllers.
By continuous modulation the motor current/ voltage almost reaches the optimum shape of a sine wave.

Here is a direct comparison on the oscilloscope:

This results in several advantages where the main ones seem to be:

  • Lower torque ripple
  • Lower noise
  • Higher efficiency

On the other hand there are some disadvantage:

  • More processing power needed
  • The algorithm demands a precise position and current measurement
    I think the last point might be the main reason for FOC not working with efoils that good. AND as stated in the paper below the two algorithms demand different kind of hardware. For this reason the VESC (specifically designed for FOC) might perform worse than a equally dimensioned BLDC controller.

I found this paper from Infineon with some detailed comparison of BLDC and FOC (please treat the information with caution - in the end they want to sell their chips I guess). Also I know from a professional standpoint that BLDC (block commutation) is used intentionally without sensors once the RPM is above a certain threshold due to better efficiency.

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