Question 2 Draw the per-unit reactance diagram for the system shown below. Transformers 1 and 3 are identical. Transformers 2 and 4 are identical too. 1) Choose a base of 11 KV, 100 MVA in the generator side. Calculate the current in each transmission line. I 2) Choose a base of 11 KV, 100 MVA in the Motor side. Calculate the current in each transmission line. j25a +3E 11 kv 100 MVA 9% Bet T₁ T₂ Bet Et 11.5/115 kv 60 MVA 8% j182 T₁ = T₂ and Tu toe 11516-640 70 MA 10% T₂ =T4 M 6.6kv 80 MVA 18%

Question 2 Draw the per-unit reactance diagram for the system shown below. Transformers 1 and 3 are identical. Transformers 2 and 4 are identical too. 1) Choose a base of 11 KV, 100 MVA in the generator side. Calculate the current in each transmission line. I 2) Choose a base of 11 KV, 100 MVA in the Motor side. Calculate the current in each transmission line. j25a +3E 11 kv 100 MVA 9% Bet T₁ T₂ Bet Et 11.5/115 kv 60 MVA 8% j182 T₁ = T₂ and Tu toe 11516-640 70 MA 10% T₂ =T4 M 6.6kv 80 MVA 18%

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

Chapter8: Symmetrical Components

Section: Chapter Questions

Problem 8.41P

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Consider the single-Line diagram of a power system shown in Figure 3.42 with equipment ratings given: Generator G1: 50MVA,13.2kV,x=0.15p.u. Generator G2: 20MVA,13.8kV,x=0.15p.u. Three-phase -Y transformer T1: 80MVA,13.2/165YkV,X=0.1p.u. Three-phase Y- transformer T2: 40MVA,165Y/13.8kV,X=0.1p.u. Load: 40MVA,0.8PFlagging,operatingat150kV Choose a base of 100 MVA for the system and 132-kV base in the transmission-line circuit. Let the load be modeled as a parallel combination of resistance and inductance. Neglect transformer phase shifts. Draw a per-phase equivalent circuit of the system showing all impedances in per unit.
Three single-phase two-winding transformers, each rated 25MVA,34.5/13.8kV, are connected to form a three-phase bank. Balanced positive-suence voltages are applied to the high-voltage terminals, and a balanced, resistive Y load connected to the low-voltage terminals absorbs 75 MW at 13.8 kV. If one of the single-phase transformers is removed (resulting in an open connection) and the balanced load is simultaneously reduced to 43.3 MW (57.7 of the original value), determine (a) the load voltages Va,Vb, and Vc; (b) load currents Ia,Ib, and Ic; and (c) the MVA supplied by each of the remaining two transformers. Are balanced voltages still applied to the load? Is the open transformer overloaded?
With generator conyention, where the current leaves the positive terminal of the circuit element, if P is positive then positive real power is delivered. (a) False (b) True
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