Q4.A power system with two generators is shown in the figure below. The system (generators, buses
and transmission lines) is protected by six overcurrent relays R_{1} to R_{6}. Assuming a mix of
directional and nondirectional relays at appropriate locations, the remote backup relays for R_{4} are

Answer : Option D Explaination / Solution: No Explaination.

Q5.A power system has 100 buses including 10 generator buses. For the load flow analysis using Newton-Raphson method in polar coordinates, the size of the Jacobian is

Q7.Consider a causal LTI system characterized by differential equation The response of the system to the input where u(t) denotes the unit step
function, is

Q8.The inductance and capacitance of a 400 kV, three-phase, 50 Hz lossless transmission line are 1.6 mH/km/phase and 10 nF/km/phase respectively. The sending end voltage is maintained at 400 kV. To maintain a voltage of 400 kV at the receiving end, when the line is delivering 300 MW load, the shunt compensation required is

Q9.Three single-phase transformers are connected to form a delta-star three-phase transformer of 110 kV/ 11 kV. The transformer supplies at 11 kV a load of 8 MW at 0.8 p.f. lagging to a nearby plant. Neglect the transformer losses. The ratio of phase currents in delta side to star side is