A unity feedback system has the open-loop transfer function K G(s)= s(s+2)(s* +85 +40) The Root Locus Plot for the above
Posted: Tue Apr 26, 2022 3:15 pm
A unity feedback system has the open-loop transfer function K G(s)= s(s+2)(s* +85 +40) The Root Locus Plot for the above system is given in Figure 3. a) Identify quantitatively, all essential features of the plot. For full marks, consider all relevant steps involved in plotting a root locus plot. Translate all relevant values onto the Root Locus plot given in Figure 3 illustrating all relevant labels. (You may use a printout or draw a clean sketch on your answer booklet before translating the labels). b) From the plot, using the “magnitude condition”, find the value of gain that will make the system marginally stable. How does this value compare with the corresponding value predicted in part (a)? 10 Root Locus 0.5 0.34 0.16 0.76 0.64 0.86 8 0.94 4 0.985 14 12 10 8 6 4 N Imaginary Axis (seconds) -0.985 .4 4 0.94 -6 -8 0.86 0.76 -10 -15 -10 5 0.64 0.5 0.34 0.16 -5 0 Real Axis (seconds) Figure 3 (For Question 4)