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Dr.D

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- I'm interested in calculating the transient starting torque of salient pole synchronous motors. Can someone point me to a paper or other reference that develops the theory for this calculation, please?

It is pretty well known among electrical machines folk that large, salient pole electrical machines start typically with the field winding shorted and starting torque developed by current induced in the damper windings, acting much like a squirrel cage induction machine. The net machine torque pulsates rather strongly at twice slip frequency, a pulsation that often causes problems in the connected mechanical load. I read (on the internet) that motor manufacturers can typically provide curves for the "steady (accelerating) torque" and for the "pulsating torque," each as functions of slip. This raises several questions for me.

1) I'd like to know how these torque amplitudes are calculated for each slip value?

2) Is there any way to know the phasing of these torque pulsations?

3) Is there a way to estimate these torque amplitudes (as functions of slip) without detailed design information, say using just name plate data for the machine.

Direction to any sources (books, papers, web sites) would be much appreciated.

1) I'd like to know how these torque amplitudes are calculated for each slip value?

2) Is there any way to know the phasing of these torque pulsations?

3) Is there a way to estimate these torque amplitudes (as functions of slip) without detailed design information, say using just name plate data for the machine.

Direction to any sources (books, papers, web sites) would be much appreciated.

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