What Is "stator magnetizing inductance"

Altair Forum User
Altair Forum User
Altair Employee
edited October 2020 in Community Q&A

Submitted by Joe on Fri, 04/27/2012 - 03:23

 

This is a parameter on many of the Motion blocks. What does it mean and how do I find it?

Tagged:

Answers

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited June 2016

    Submitted by Duco Pulle on Fri, 04/27/2012 - 03:41.

    Okay lets start from first principles: inductance (L) is the ratio of flux divided by current( or voltage divided by rate of current change). So if you apply a current to the phase winding then a flux will result. Of the flux that a winding 'sees' part of this is leakage flux, which is the component of the flux that does not cross the airgap to the rotor, IE it is only seen by the stator winding. That flux component divided by the applied current is the leakage inductance. The other flux component that crosses the airgap (twice of course) is called magnetizing flux from its use in induction motors to induce current flow and a resulting magnetic field in the nonmagnetic but conducting rotor. In PM machines, this flux component is small compared to the leakage flux as it passes through air and magnets (which are also seen as air), so it has a larger path through air than the leakage flux which sits nears the flux concentrating slots.
    The flux that crosses the air gap divided by the excitation current is the magnetizing inductance. The sum of magnetizing inductance and leakage inductance is the stator inductance (which is half the terminal inductance in a wye connected motor) see equation 6.2 of our book. Indeed measuring the magnetizing component separate from the stator inductance as a whole is difficult, finite element approach is then the way to go, but it is not needed for motor simulation as the total inductance is required in this case. Hope this helps, -Duco

Categories