A 3-ph system is shown below where a generator supplies power to a synchronous motor. The operating data for the motor is it draws 45 MVA at (G) 0.8 pf lag at terminal voltage Vm = 9 kV. The rated data for other devices are given below. (a) Draw the per unit impedance diagram for the system by selecting common bases as 200 MVA for the system and 20 kV for the generator. (b) Show that the generator internal voltage must be at 11.032 kV. (c) Re-draw the per unit impedance diagram by selecting common bases as 999 MVA for the system and 99 kV for the motor. What must be the generator internal voltage in kV as per new base values. G 100 MVA, 10 kV, X = 0.1 pu T1 10/100 kV, 100 MVA, X = 0.1 pu T2 100/10 kV, 100 MVA, X = 0.1 pu Line 100 kV, R = 10 \Omega, X = 20 \Omega

A 3-ph system is shown below where a generator supplies power to a synchronous motor. The operating data for the motor is it draws 45 MVA at (G) 0.8 pf lag at terminal voltage Vm = 9 kV. The rated data for other devices are given below. (a) Draw the per unit impedance diagram for the system by selecting common bases as 200 MVA for the system and 20 kV for the generator. (b) Show that the generator internal voltage must be at 11.032 kV. (c) Re-draw the per unit impedance diagram by selecting common bases as 999 MVA for the system and 99 kV for the motor. What must be the generator internal voltage in kV as per new base values. G 100 MVA, 10 kV, X = 0.1 pu T1 10/100 kV, 100 MVA, X = 0.1 pu T2 100/10 kV, 100 MVA, X = 0.1 pu Line 100 kV, R = 10 \Omega, X = 20 \Omega

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.56P: Three single-phase two-winding transformers, each rated 3kVA,220/110volts,60Hz, with a 0.10 per-unit...

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