The one line diagram of a simple power system is shown in below figure. XT-8% BE X=20% G 100 MVA 1 20/66 kV 20 kV 100 MVA 2 Xt-15 f2 Xr-10% to M 3 20 MW/ 66 kV P.F-0.8 Lag. All Sub transient reactance Xd" are expressed in percentage. The motor is operating at full load with lagging power factor 0.8 Assume the the three phase fault occurs through bus 2. Calculate the voltage (bus 1) in per unit during the fault. Choose 20 kV as the voltage base for generator and 100-MVA base.

The one line diagram of a simple power system is shown in below figure. XT-8% BE X=20% G 100 MVA 1 20/66 kV 20 kV 100 MVA 2 Xt-15 f2 Xr-10% to M 3 20 MW/ 66 kV P.F-0.8 Lag. All Sub transient reactance Xd" are expressed in percentage. The motor is operating at full load with lagging power factor 0.8 Assume the the three phase fault occurs through bus 2. Calculate the voltage (bus 1) in per unit during the fault. Choose 20 kV as the voltage base for generator and 100-MVA base.

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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