The three-phase ratings of a three-winding transformer are: Primary Y-connected, 66 kV, 24 MVA Y-connected, 13.2 kV, 12 MVA Secondary Tertiary A-connected, 2.3 kV, 4 MVA Neglecting resistance, the leakage impedances are: Zps = 6% on 24 MVA, 66 kV base Znt 8% on 24 MVA, 66 kV base "pt = Zst = 7% on 12 MVA, 13.2 kV base Find the per-unit impedances of the per-phase equivalent circuit for a base of 24 MVA, 66 kV in the primary circuit. {Ans: j 0.0; j 0.06; j 0.08}

Two transformers are to be operated in parallel such that they share load in proportion to their KVA rating. The rating of the first transformer is 500 kVA and its pu leakage impedance is 0.05 pu. If the rating of second transformer is 250 kVA, then its pu leakage impedance is A 0.20 B 0.10 C 0.05 D 0.025

In the medium and large transformers, the total copper losses should be A2 % of the rated output. (a) 0.7 to 0.9 (b) 0.5 to 2 (c) 0.2 to 0.6 (d) 0.4 to 1 In DC machines, provides the magnetic path as well as the

Three single phase transformers are connected in a Delta-Wye configuration.  Each transformer is rated 13kV/64kV.  The transformers are connected to a 3 phase 13kV (L-L) supply and the balanced three phase load is 788KVA. What is the current magnitude in the secondary winding of each transformer? explain the steps too please