1
GATE EE 2003
+2
-0.6
Figure shows an ideal single-phase transformer. The primary and secondary coils are wound on the core as shown. Turns ratio $$\left(\frac{N_1}{N_2}\right)$$=2. The correct phasors of voltages $$E_1,\;E_2$$ currents $$I_1,\;I_2$$ and core flux $$\phi$$ are as shown in
A
B
C
D
2
GATE EE 2003
+2
-0.6
Figure shows a $$\triangle$$ - Y connected 3-phase distribution transformer used to step down the voltage from 11000 V to 415 V line-to line. It has two switches S1 and S2. Under normal conditions S1 is closed and S2 is open. Under certain special conditions S1 is open and S2 is closed. In such a case the magnitude of the voltage across the LV terminals a and c is
A
240 V
B
480 V
C
415 V
D
0 V
3
GATE EE 2003
+2
-0.6
Figure shows an ideal three-winding transformer. The three windings 1,2,3 of the transformer are wound on the same core as shown. The turn's ratio N1:N2:N3 is 4:2:1. A resistor of 10 Ω is connected across winding-2. A capacitor of reactance 2.5 Ω is connected across winding-3. Winding-1 is connected across a 400 V, ac supply. If the supply voltage phasor $$\overline V=400\angle0^\circ$$, the supply current phasor $${\overline I}_1$$ is given by
A
(-10 + j10) A
B
(-10 - j10) A
C
(10 + j10) A
D
(10 - j10) A
4
GATE EE 2002
+2
-0.6
A 400V/200V/200V, 50 Hz three winding transformer is connected as shown in Figure. The reading of the voltmeter 'V' will be
A
0 V
B
400 V
C
600 V
D
800 V
EXAM MAP
Medical
NEET