Q1) The equivalent low-side parameters of a 250kVA, 4160 - 480V, 60 = = 0.0433 9. The Hz transformer are Req,LS 0.00920 and Xeq, LS transformer is operated in the step-down mode and is delivering rated current at rated voltage to a 0.840 power-factor lagging load. Determine: the no-load voltage, the actual input voltage on the high-side, the high- side current, the input impedance, and the voltage regulation.

A transformer having a nominal voltage = 399V and a no load voltage = 420V at its secondary, the short circuit current at the secondary of this transformer in function of its nominal current will be: Select one: Isc=10*In None of these Isc=30*In Isc=20*In Isc=40*In

A real transformer has Np-500, Ns-100, Rp-3.52, Rs-22, Xp=202, and Xs-82. A 65V RMS source and a 20225° load are connected to the transformer. Draw the circuit and calculate the magnitude of the voltage across the load.

For all questions in this page, assume that the transformer is ideal. One side of a transformer has 280 turns while the other side has 140 turns. The high voltage side is connected to a 120 Vrms source. The low voltage side (secondary) is connected to an impedance Z₁ = 11.7 + j6.8 0. provide at least 2 digits after the What is the value of the load impedance when referred to the primary? Referred impedance = Q

b) A lkQ resistance is connected across the secondary winding of a 200V/400V transformer with the following equivalent circuit parameters, Kleq=502, Rc = 10k2, XM =1 k2 , ^leq = 100 2. Determine the following: R i. The Open Circuit Output Voltage (Vsoc) ii. The Output Voltage under load (Vs) i1i. The Output Current (Is) iv. The Transformer Efficiency (%)

figure the S-parameters for an ideal transformer with turn ratio N = N1:N2 where N1 is the no.of turns of the primary winding and N2 is the no. of turns of the secondary winding.