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stability

GATE Electrical Engineering · Power Systems - Stability · 1991-2025

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2
elite explanations
23
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2025 Q2

Let $G(s) = \frac{1}{(s+1)(s+2)}$. Then the closed-loop system shown in the figure below, is

mediumanswer key
2025 Q23

The Nyquist plot of a strictly stable G(s) having the numerator polynomial as (s – 3) encircles the critical point –1 once in the anti-clockwise direction. Which one of the followi...

mediumanswer key
2025 Q41

Let $G(s) = \frac{1}{(s+1)(s+2)}$. Then the closed-loop system shown in the figure below, is

mediumanswer key
2025 Q49

In the system shown below, the generator was initially supplying power to the grid. A temporary LLLG bolted fault occurs at F very close to circuit breaker 1. The circuit breakers...

hardanswer key
2023 Q13

In the Nyquist plot of the open-loop transfer function $G(s)H(s) = \frac{3s + 5}{s - 1}$ corresponding to the feedback loop shown in the figure, the infinite semi-circular arc of t...

medium
2023 Q27

Which of the following statement(s) is/are true?

medium
2023 PYQ

Which of the following statement(s) is/are true?

mediumanswer keyelite explanation
2022 PYQ

The open loop transfer function of a unity gain negative feedback system is given by $$G(s) = {k \over {{s^2} + 4s - 5}}$$. The range of k for which the system is stable, is

easyanswer keybasic explanation
2019 Q15

The characteristic equation of a linear time-invariant (LTI) system is given by $\Delta(s) = s^4 + 3s^3 + 3s^2 + s + k = 0$. The system is BIBO stable if

medium
2018 Q11

A closed loop system has the characteristic equation given by s³ + Ks² + (K+2)s + 3 = 0. For this system to be stable, which one of the following conditions should be satisfied?

mediumanswer key
2018 Q22

Consider the unity feedback control system shown. The value of K that results in a phase margin of the system to be 30° is ______. (Give the answer up to two decimal places.)

hardanswer key
2018 Q34

The number of roots of the polynomial, $s^7 + s^6 + 7s^5 + 14s^4 + 31s^3 + 73s^2 + 25s + 200$, in the open left half of the complex plane is

hardanswer key
2018 Q35

The range of K for which all the roots of the equation s³ + 3s² + 2s + K = 0 are in the left half of the complex s-plane is

mediumanswer key
2018 Q55

The figure shows the single line diagram of a power system with a double circuit transmission line. The expression for electrical power is 1.5 sin δ, where δ is the rotor angle. Th...

hardanswer key
2017 PYQ

A closed loop system has the characteristic equation given by $${s^3} + K{s^2} + \left( {K + 2} \right)s + 3 = 0.$$ For this system to be stable, which one of the following conditi...

easyanswer key
2017 PYQ

The range of K for which all the roots of the equation $${s^3} + 3{s^2} + 2s + K = 0$$ are in the left half of the complex $$s$$-plane is

easyanswer key
2016 PYQ

Given the following polynomial equation $${s^3} + 5.5{s^2} + 8.5s + 3 = 0$$ the number of roots of the polynomial which have real parts strictly less than $$-1$$ is _____________.

medium
2016 PYQ

Loop transfer function of a feedback system is $$G\left( s \right)H\left( s \right) = {{s + 3} \over {{s^2}\left( {s - 3} \right)}}.$$ Take the Nyquist contour in the clockwise dir...

mediumanswer key
2015 PYQ

The following discrete-time equations result from the numerical integration of the differential equations of an un-damped simple harmonic oscillator with state variables $$𝑥$$ and...

mediumanswer key
2014 PYQ

In the formation of Routh-Hurwitz array for a polynomial, all the elements of a row have zero values. This premature termination of the array indicates the presence of

easyanswer key
2014 PYQ

A single-input single-output feedback system has forward transfer function $$𝐺(𝑠)$$ and feedback transfer function $$𝐻(𝑠).$$ It is given that $$\left| {G\left( s \right)H\left(...

mediumanswer key
2013 PYQ

Which one of the following statements is NOT TRUE for a continuous time causal and stable LTI system?

easyanswer key
2011 PYQ

An open loop system represented by the transfer function $$G\left( s \right) = {{\left( {s - 1} \right)} \over {\left( {s + 2} \right)\left( {s + 3} \right)}}$$ is

easyanswer key
2010 PYQ

The system $$\mathop X\limits^ \bullet = AX + BU$$ with $$A = \left[ {\matrix{ { - 1} & 2 \cr 0 & 2 \cr } } \right],$$ $$B = \left[ {\matrix{ 0 \cr 1 \cr } } \right]$$ is

easyanswer key
2009 PYQ

A cascade of 3 Linear Time Invariant systems is casual and unstable. From this, we conclude that

mediumanswer keyelite explanation
2009 PYQ

The first two rows of Routh's tabulation of a third order equation are as follows $$$\left. {\matrix{ {{s^3}} \cr {{s^2}} \cr } } \right|\matrix{ 2 & 2 \cr 4 & 4 \cr } $$$ this mea...

mediumanswer key
2008 PYQ

A system with input $$x(t)$$ and output $$y(t)$$ is defined by the input $$-$$ output relation: $$y\left( t \right) = \int\limits_{ - \infty }^{ - 2t} {x\left( \tau \right)} d\tau...

mediumanswer key
2006 PYQ

The algebraic equation $$F\left( s \right) = {s^5} - 3{s^4} + 5{s^3} - 7{s^2} + 4s + 20$$ $$F\left( s \right) = 0$$ has

mediumanswer key
2006 PYQ

A discrete real all pass system has a pole at $$z = 2\angle {30^ \circ };\,$$ it, therefore,

mediumanswer key
2004 PYQ

For the equation, $${s^3} - 4{s^2} + s + 6 = 0$$ the number of roots in the left half of $$s$$ plane will be

easyanswer key
2004 PYQ

A unity feedback system, having an open loop gain becomes stable when $$G\left( s \right)H\left( s \right) = {{K\left( {1 - s} \right)} \over {\left( {1 + s} \right)}}$$

easyanswer key
2004 PYQ

The Nyquist plot of loop transfer function $$G(s) H(s)$$ of a closed loop control system passes through the point $$(-1,j0)$$ in the $$G(s) H(s)$$ plane. The phase margin of the sy...

easyanswer key
2002 PYQ

For the system $$X = \left[ {\matrix{ 2 & 3 \cr 0 & 5 \cr } } \right]X + \left[ {\matrix{ 1 \cr 0 \cr } } \right]u,$$ Which of the following statement is true?

easyanswer key
2002 PYQ

A unity feedback system has an open loop transfer function, $$G\left( s \right) = {K \over {{s^2}}}.$$ The root locus plot is

easyanswer key
2001 PYQ

Given the homogeneous state-space equation $$\mathop X\limits^ \bullet = \left[ {\matrix{ { - 3} & 1 \cr 0 & { - 2} \cr } } \right]x$$ the steady state value of $$\,\,{x_{ss}}\,\,...

easyanswer key
2001 PYQ

A unity feedback system has an open-loop transfer function of $$G\left( s \right) = {{10000} \over {s{{\left( {s + 10} \right)}^2}}}$$ (a) Determine the magnitude of $$G\left( {j\o...

medium
2000 PYQ

Open-loop transfer function of a unity - feedback system is $$$G\left( s \right) = {G_1}\left( s \right).{e^{ - s{\tau _D}}} = {{{e^{ - s{\tau _D}}}} \over {s\left( {s + 1} \right)...

hard
2000 PYQ

A unity feedback system has open loop transfer function $$G\left( s \right) = {{K\left( {s + 5} \right)} \over {s\left( {s + 2} \right)}};K \ge 0$$ (a) Draw a rough sketch of the r...

hard
2000 PYQ

Out of the considerations (i) to (iv) listed below, (i) No distance limitation related to steady state stability (ii) No reactive power requirement from the system at the two termi...

mediumanswer key
1998 PYQ

The number of roots on the equation $$2{s^4} + {s^3} + 3{s^2} + 5s + 7 = 0$$ that lie in the right half of $$S$$ plane is:

easyanswer key
1997 PYQ

The system represented by the transfer function $$G\left( s \right) = {{{s^2} + 10s + 24} \over {{s^4} + 6{s^3} - 39{s^2} + 19s + 84}}$$ has . . . pole $$(s)$$ in the right-half $$...

medium
1994 PYQ

HVDC transmission is preferred to EHV __ AC because

easyanswer key
1994 PYQ

The number of positive real roots of the equation $${s^3} - 2s + 2 = 0$$ is __________.

medium
1991 PYQ

A unity feedback system has the forward loop transfer function $$G\left( s \right) = {{K{{\left( {s + 2} \right)}^2}} \over {{s^2}\left( {s - 1} \right)}}$$ (a) Determine the range...

medium