GATE EC|| CONTROL SYSTEM ||GAIN & PHASE MARGIN|| PYQS(2000-2025)

In the feedback system shown below [Tex]G(s) = \frac{1}{(s + 1)(s + 2)(s + 3)}[/Tex]

The positive value of K for which the gain margin of the loop is exactly 0 dB and the phase margin of the loop is exactly zero degree is

(GATE 2016 || EC || MCQ ||2 MARK)

The phase margin (in degrees) of the system

is _

The phase margin in degrees of

calculated using the asymptotic Bode plot is

(GATE 2014 || EC || MCQ ||2 MARK)

The gain margin of the system under closed loop unity negative feedback is

[Tex]G(s)H(s) = \frac{100}{s(s + 10)^2}[/Tex]
(GATE 2011 || EC || MCQ ||2 MARK)

The Nyquist plot of G(jω)H(jω) for a closed-loop control system passed through (–1, j0) point in the GH plane. The gain margin of the system in dB is equal to
( GATE 2006 || EC || MCQ ||2 MARK)

With the value of "a" set for the phase margin of π/4, the value of the unit-impulse response of the open-loop system at t = 1 second is equal to
(GATE 2006 || EC || MCQ ||2 MARK)

The value of "a" so that the system has a phase-margin equal to π/4 is approximately equal to

( GATE 2006 || EC || MCQ ||1 MARK)

The open-loop transfer function of a unity feedback system is given by

[Tex]G(s) = \frac{3e^{-2s}}{s(s+2)}[/Tex]

Based on the above results, the gain and phase margins of the system will be

(GATE 2005 || EC || MCQ ||2 MARK)

The open-loop transfer function of a unity feedback system is given by

[Tex]G(s) = \frac{3e^{-2s}}{s(s+2)}[/Tex]
(GATE 2005 || EC || MCQ ||2 MARK)

The gain margin and the phase margin of a feedback system with

[Tex]G(s)H(s) = \frac{s}{(s+100)^3}[/Tex] are

(GATE 2003 || EC || MCQ ||2 MARK)