Question

Figure shows a one-line diagram of a three-phase system. Assume that the line length between the two transformers is negligible and the three-phase generator is rated 4160 kVA, 2.4 kV, and 1000 A and that it supplies a purely inductive load of Ipu = 2.b8∠−90° pu. The three-phase transformer T1 is rated 6000 kVA, 2.4Y−24Y kV, with leakage reactance of 0.04 pu. Transformer T2 is made up of three single-phase transformers and is rated 4000 kVA, 24Y−12Y kV, with leakage reactance of 0.04d pu. Determine the following for all three circuits, 2.4-, 24-, and 12-kV circuits: 

(a) Base kVA values 

(b) Base line-to-line kilovolt values 

(c) Base impedance values 

(d) Base current values 

(e) Physical current values (neglect magnetizing currents in transformers and charging currents in lines) 

(f) Per-unit current values 

(g) New transformer reactances based on their new bases 

(h) Per-unit voltage values at buses 1, 2, and 4 

(i) Per-unit apparent power values at buses 1, 2, and 4 

(j) Summarize results in a table

(Roll=abcd)