Anyone know roughly what the switching frequency for FOC mode is?
In BLDC its just motor_phases * voltage * Kv since the MOSFETs only switch once per phase
In FOC, I imagine its MUCH higher, something like 4-5 switches per phase? Anyone know?
You can set it in Vesc tool
AFAIK bldc is also switching through each phase.
It has to modulate each phase using something PWM-esque to vary the voltage. That’s how you get variable drive speed.
FOC maybe?
No, BLDC is most certainly modulating each phase to limit voltage.
FOC is switching much more frequently to output a smooth sine wave. (I’m not an expert)
EDIT: see @Pedrodemio 's explanation for something that makes more sense.
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In BLDC the switching frequency is variable and as you said depends in RPM
In FOC is a fixed number, the defaults is 20 kHz, but some motors are pretty noisy at that value, you can up that to 30 kHz and be truly silent
The fixed frequency is due it using PWM to form a sinewave
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