speed control of dc motor by chopper

[alex dhaduk]

hello...........
i am using two quadrant chopper for speed control of 1/4 hp,48 volt dc motor with pwm.
then

what will be the switching frequency of the pwm for the MOSFET ????????????????/

 

[Pjdd]

In principle, you can use almost any frequency. Frequencies in the audio range can result in a whining sound. In my last design of a PWM-controlled motor drive, I used a frequency of about 25kHz.