Problems 1. Two synchronous machines are connected through three phase transformer to the transmission line as given in Fig. the ratings and reactance's of the machines and transformers are: Machines 1 and 2: 100 MVA; 20 kV; Xd"=X1=X2=20%; XO = 4%; Xn= 5% Transformers T1 and T2: 100MVA; 20/ 345 kV ; X=8% The line reactance's are X1=X2= 15% and X0=50%. The system is operating at nominal voltage without prefault currents when a bolted single line to ground fault occurs on the phase 'a' at bus 3. Determine the subtransient current to ground at the fault

Problems 1. Two synchronous machines are connected through three phase transformer to the transmission line as given in Fig. the ratings and reactance's of the machines and transformers are: Machines 1 and 2: 100 MVA; 20 kV; Xd"=X1=X2=20%; XO = 4%; Xn= 5% Transformers T1 and T2: 100MVA; 20/ 345 kV ; X=8% The line reactance's are X1=X2= 15% and X0=50%. The system is operating at nominal voltage without prefault currents when a bolted single line to ground fault occurs on the phase 'a' at bus 3. Determine the subtransient current to ground at the fault

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

Chapter11: Transient Stability

Section: Chapter Questions

Problem 11.19P

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