[SOLVED] starting torque of inverter

[ngochaigv888]

i want use inverter to control 3phase motor. i don't know, when speed's motor. is starting torque small?

 

[schmitt trigger]

A good, variable FREQUENCY drive, will have a starting torque identical or larger to the torque of the motor connected across the mains.

Torque is dependent on SLIP, and slip can be controlled by varying the frequency.

 

[ngochaigv888]

A good, variable FREQUENCY drive, will have a starting torque identical or larger to the torque of the motor connected across the mains.

Torque is dependent on SLIP, and slip can be controlled by varying the frequency.

I think. initial frequency is very small. slip is small too.
if direct provided 50hz of supply to torque is elder.

 

[FvM]

Are you talking about the maximum available starting torque (e.g. needed to overcome the breakaway torque of a machine) or the actual starting torque with a medium or light load?

The maximum torque of a VFD driven motor can be considerably larger than the starting torque of a direct driven induction motor. The actual torque will be determined by the VFD speed ramp and typically lower than in direct drive, it's also working as a soft starter.

 

[ngochaigv888]

example: i start of motor at 5hz of frequency , but rated frequency is 50hz
so, is it running.
thank for attention.