GATE 2022 : National Champion Quiz 3

What happens during the Ferranti effect?

The z transform of is

Two identical unloaded generators are connected in parallel as shown below. Both the generators are having positive, negative and zero sequence impedance of j0.8 p.u., j0.2 p.u. and j0.3 p.u. respectively. If pre-fault voltage is 1 p.u. for a line to ground fault at the terminals of the generator, the fault current magnitude (in p.u.) is ___________. (Assume neutral impedance, Z_n = j0.02 p.u.)

The Exponential fourier series(EFS) expansion of a signal is

The fundamental period of x(t) is_________ (in sec)

Consider a CT (500/1), protecting a feeder. This CT is being used by IDMT type relay. If relay has plug setting 125% and time multiplier setting of 0.3

If fault current is 5000 A, Then which of the following option(s) are correct.

The fourier transform of a signal x(t) is X(w) and is a defined below.

The energy of the signal x(t) is______

A 11KV alternative protected by the balanced circulating current system has its neutral grounded through a resistance. The relay will operate for an out of balance current of 2A is the pilot wires which are connected to the secondary windings of 1000/5 ratio CT.

The minimum value of earthing resistance (in ohms) required to protect 75% of the winding is _____.

The block diagram representation of a system is shown in figure below

The differential equation description of this system can be given as

A 3-ϕ, 50 Hz, synchronous generator has rating 150 MVA . The kinetic energy of the machine at synchronous speed is 600 MJ. The machine is running steadily at synchronous speed and delivering 40 MW power at power angle of 15 electrical degrees. If load is suddenly removed, assuming the acceleration is constant for 8 cycles, the value of power angle after 5 cycle is _______ electrical degrees.

The time signal corresponding to