An electrical load of 250Kva has a pf of 0.65 inductive. Connects to the same network a 75kW star synchronous motor, with 88% efficiency, to raise the pf of the installation at 0.85 inductive. a) Calculate the apparent pf of the synchronous motor and the pf at which it will work. b) If the supply voltage is 380V, and the motor has a synchronous impedance of j0.5 ohms per phase determine the induced emf of the machine.

An electrical load of 250Kva has a pf of 0.65 inductive. Connects to the same network a 75kW star synchronous motor, with 88% efficiency, to raise the pf of the installation at 0.85 inductive. a) Calculate the apparent pf of the synchronous motor and the pf at which it will work. b) If the supply voltage is 380V, and the motor has a synchronous impedance of j0.5 ohms per phase determine the induced emf of the machine.

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter39: Synchronous Motor Operation

Section: Chapter Questions

Problem 14SQ: Induction motors and welding transformers require magnetizing current, which causes a. lagging power...

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