1
GATE EE 2000
MCQ (Single Correct Answer)
+2
-0.6
A transmission line has equal voltages at the two ends, maintained constant by two sources. A third source is to be provided to maintain constant voltage (equal to end voltages) at either the midpoint of the line or at $$75$$% of the distance from the sending end. Then the maximum power transfer capabilities of the line in the original case and the other two cases respectively will be in the following ratios.
A
$$1:1:1$$
B
$$1:2:{1 \over {0.75}}$$
C
$$1:2:4$$
D
$$1:4:6$$
2
GATE EE 2000
MCQ (Single Correct Answer)
+2
-0.6
The severity of line-to-ground and three phase faults at the terminals of an unloaded synchronous generator is to be same. If the terminal voltage is
$$1.0$$ p.u. and $${Z_1} = {Z_2} = j0.1\,\,$$ p.u.,
$$\,{Z_0} = j0.05\,\,\,\,\,$$ p.u., for the alternator, then the required inductive reacttance for neutral grounding is
A
$$0.0166$$ p.u.
B
$$0.05$$ p.u.
C
$$0.1$$ p.u.
D
$$0.15$$ p.u.
3
GATE EE 2000
MCQ (Single Correct Answer)
+2
-0.6
The incremental cost characteristic of two generators delivering $$200$$ $$MW$$ are as follows $$\,\,\,{{d{F_1}} \over {d{P_1}}} = 20 + 0.1{P_1},\,\,{{d{F_2}} \over {d{P_2}}} = 16 + 0.2{P_2}$$
For economic operation, the generations $${P_1}$$ and $${P_2}$$ should be
A
$${P_1} = {P_2} = 100\,MW$$
B
$${P_1} = 80MW,\,\,{P_2} = 120\,MW$$
C
$${P_1} = 200MW,\,\,{P_2} = 0\,MW$$
D
$${P_1} = 120MW,\,\,{P_2} = 80\,MW$$
4
GATE EE 2000
Subjective
+5
-0
A synchronous generator, having a reactance of 0.15 p.u., is connected to an infinite bus through two identical parallel transmission lines having reactance of 0.3 p.u. each. In steady state, the generator is delivering 1 p.u. Power to the infinite bus. For a three phase fault at the receiving end of one line, calculate the rotor angle at the end of first time step of 0.05 seconds. Assume the voltage behind transient reactance for the generator as 1.1 p.u. and infinite bus voltage as 1.0 p.u. Also indicate how the accelerating powers will be evaluated for the next time step if the breaker clears the fault.

(i) at the end of an interval
(ii) at the middle of an interval.