Power factor of motor with VSD?

AI Thread Summary
When a motor with a full load power factor of 0.8 and a starting power factor of 0.3 is equipped with a Variable Speed Drive (VSD) rated at a power factor of 0.95, the starting power factor remains at 0.3. The VSD's power input is designed to maintain a power factor of 0.95 through a power factor correction circuit. However, the DC reservoir capacitors separate the motor load's power factor from the main supply's power factor. While the VSD can improve efficiency, the motor's inherent power factor does not change. The VSD must be appropriately rated to manage the reactive VAR of the motor load effectively.
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Power factor at the motor with VSD
If I have a motor with a full load power factor of 0.8 and starting power factor of 0.3 and I install a VSD to run it with a datasheet power factor of 0.95, will the power factor during starting be 0.3 or 0.95? And at full load?

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The power input to the VSD should be maintained at 0.95 by a PF correction circuit that controls the switching input rectifier.

The DC reservoir capacitors isolate the PF of the motor load, from the PF of the main supply.

The motor PF will not change, but the VSD must be rated to handle the reactive VAR of the motor load.
 
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