(Solved): Consider the feedback control system shown in Figure 4 below. Here G(s)=(s+1)41 and K(s) is a co ...
Consider the feedback control system shown in Figure 4 below. Here G(s)=(s+1)41? and K(s) is a compensator. a) Sketch the Nyquist diagram of G(s) indicating (i) where the frequency ? is zero and (ii) where it is infinite. Also calculate the real-axis intercepts. b) Show that the closed-loop is stable and determine the gain and phase margins. c) Comment on the stability and performance properties of the closed-loop. Your answer should include analysis of tracking disturbance and noise attenuation. d) Explain what is meant by a phase-lag compensator. Your answer should include an expression for such a compensator and a description of its frequency response. e) Without doing any actual design calculations, describe how a phase-lag compensator would affect the stability margin and the steady state tracking properties of the loop. Figure 4
Given, (b) To find Gain margin and Phase margin (i) For Gain margin,the phase crossover frequency is needed to be found The phase crossover frequency is the frequency at which the phase angle first reaches ?180° Now,the gain margin is