Electrical Engineering GATE 2015 Set-2 Questions with Answer

Ques 53 General Aptitude

If the list of letters, P, R, S, T, U is an arithmetic sequence, which of the following are also in arithmetic sequence?
I. 2P, 2R, 2S, 2T, 2U
II. P-3, R-3, S-3, T-3, U-3
III. P², R², S², T², U²

Ques 54 General Aptitude

Four branches of a company are located at M, N, O, and P. M is north of N at a distance of 4 km; P is south of O at a distance of 2 km; N is southeast of O by 1 km. What is the distance between M and P in km?

Ques 55 Power Electronics

A buck converter feeding a variable resistive load is shown in the figure. The switching frequency of the switch S is 100 kHz and the duty ratio is 0.6. The output voltage V_o is 36V. Assume that all the components are ideal, and that the output voltage is ripple-free. The value of R (in Ohm) that will make the inductor current (i_L) just continuous is ________.

Ques 56 Power Electronics

For the switching converter shown in the following figure, assume steady-state operation. Also assume that the components are ideal, the inductor current is always positive and continuous and switching period is T_s. If the voltage V_L is as shown, the duty cycle of the switch S is ________.

Ques 57 Power Electronics

In the given rectifier, the delay angle of the thyristor T₁ measured from the positive going zero crossing of V_s is 30°. If the input voltage V_s is 100sin(100πt)V, the average voltage across R (in Volt) under steady-state is ________.

Ques 58 Power Systems

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?

Ques 59 Power Systems

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

Ques 60 Power Systems

The incremental costs (in Rupees/MWh) of operating two generating units are functions of their respective powers P₁ and P₂ in MW, and are given by dC₁/dP₁ = 0.2P₁+50 and dC₂/dP₂ = 0.24P₂+40, where 20MW≤P₁≤150MW and 20MW≤P₂≤150MW. For a certain load demand, P₁ and P₂ have been chosen such that dC₁/dP₁ = 76 Rs/MWh and dC₂/dP₂ = 68.8 Rs/MWh. If the generations are rescheduled to minimize the total cost, then P₂ is ________.

Ques 61 Power Systems

A composite conductor consists of three conductors of radius R each. The conductors are arranged as shown below. The geometric mean radius (GMR) (in cm) of the composite conductor is kR. The value of k is ________.

Ques 62 Power Systems

A 3-phase transformer rated for 33 kV/11 kV is connected in delta/star as shown in figure. The current transformers (CTs) on low and high voltage sides have a ratio of 500/5. Find the currents i₁ and i₂, if the fault current is 300 A as shown in figure.

Ques 63 Signals and Systems

Consider a signal defined by

Ques 64 Signals and Systems

For linear time invariant systems, that are Bounded Input Bounded Output stable, which one of the following statements is TRUE?

Ques 65 Signals and Systems

The z-Transform of a sequence x[n] is given as X(z) = 2z + 4 - 4/z + 3/z². If y[n] is the first difference of x[n], then Y(z) is given by