PWM Choice of switching Frequency

[pranay.upadhyay]

PWM Frequency

Hello,

What should be the Maximum operating PWM frequency for controlling the BLDC motor.

IS it any factor for choosing the PWM frequency?

As we tested it with, 16, 20 40 and 50 Khz. It work better at higher speed.

Please reply.

-Regards,
Pranay

 

[btbass]

Re: PWM Frequency

Switching loses.
The power device dissipates maximum power while switching, the higher the switching frequency, the more power the device has to dissipate.
The pwm frequency is normally chosen so it is out of the audio band so you cant hear it.
16KHz is a common choice of switching speed.

 

[Mr.Cool]

agreed with above comments.

switching frequency should be 10's greater than fundamental frequency (at least). it can be quite a bit higher if you also want to get out of audible range.

you probably need a filter between your inverter and your motor so that health of your motor can be maintained.

Mr.Cool