Running 03Nos Single Phase Motors By A 3Phase Vfd

[AB2005]

Hi;

I want to control the speed of 3 single phase motors each 120W by a 3phase inverter drive. In this case, the motors will be connected in star connection. How about this idea? Please share your experience.

[marke]

Hello AB2005

 

If the three motors are identical, and all operate at the same time, and at the same load, and are shaded pole motors, then this will work fine.

If the motors have a start winding along with a start switch to connect and disconnect that winding, then the impedance will be so variable, that the voltage applied to each motor will change and there will be issues.

 

It works well for shaded pole fan motors, but some of these motors do not like the PWM waveform and can overheat with increased slip losses.

 

There is a VFD designed for use with single phase motors, you would need one VFD per motor.

 

Best regards,

Mark