GATE EE 2015 Question Paper (07-Feb-2015) (Shift 2)

The synchronous generator shown in the figure is supplying active power to an infinite bus via two short, lossless transmission lines, and is initially in steady state. The mechanical power input to the generator and the voltage magnitude E are constant. If one line is tripped at time t₁ by opening the circuit breakers at the two ends (although there is no fault), then it is seen that the generator undergoes a stable transient. Which one of the following waveforms of the rotor angle δ shows the transient correctly?

A 3 – bus power system network consists of 3 transmission lines. The bus admittance matrix of the uncompensated system is

≤ft[ {*20c - j6&j3&j4\\ j3& - j7&j5\\ j4&j5& - j8 } ]Pu

If the shunt capacitance of all transmission lines is 50% compensated, the imaginary part of the 3${}^{rd}$ row 3${}^{rd}$ column element (in pu) of the bus admittance matrix after compensation is

A series RL circuit is excited at t = 0 by closing a switch as shown in the figure. Assuming zero initial conditions, the value of $\frac{d^{2}i}{d{t}^2}att=0^{+}$ is

The current i (in Ampere) in the 2 Ω resistor of the given network is _____.

Find the transformer ratios a and b that the impedance Zᵢₙ is resistive and equal to 2.5 Ω when the network is excited with a sine wave voltage of angular frequency of 5000 rad/s