I am doing 6 step commutation of 3 phase Synchronous motor. The pwm frequency is around 10khz. I read the formula from the documents for synchronous speed as 120 * f / p. What is the "f" here is it 10khz ? Please advise.

 

Frequency in that formula is in Hertz.

Regards, Dana.

 

"f" is the PWM modulation frequency, not the PWM switching frequency.
f would be 50-60Hz for standard motor operation.
Are you trying to control the synchronous motor speed with the PWM signal?

 

Not sure but in documents i read that the switching frequency should be high to avoid audible noise. How to program the pwm modulation frequency ? I mean to say i want higher speeds how to increase modulation frequency ?

 

Interesting reference -

https://www.nxp.com/docs/en/reference-manual/DRM018.pdf

Regards, Dana.

 

Picmicro recommend PWM motor control starting at around 5khz to 6khz to avoid audible buzz or noise, for a very small motor that might be an insignificant factor.
Max.

 

How to program the pwm modulation frequency ?

Depends upon what is generating the PWM.

 

Interesting reference -

https://www.nxp.com/docs/en/reference-manual/DRM018.pdf

Regards, Dana.

Does it mean i cannot do it with 120 mode of switching. Only SVPWM is the solution for torque control.

 

What do you mean by "120" mode ? Just the fact you are
switching in each phase of a 3 phase system ?

The ref I gave you not exact solution to your problem, more
generalized considerations for 3 phase motor control.

Regards, Dana.