Consider the control system shown in Figure 1. Using root locus method, design a
Compensator such that the unit step response curve will exhibit:
a. A maximum overshoot 15%
b. A settling time
t, ≤ 3.5 s
c. Suppose that initially the controller is a simply an amplifier with a gain K. Using
Routh Hurwitz criterion determine the range of gain K for stability. Find the
critical gain.
d.
Sketch the root locus of the system
e. Calculate the static velocity error for a ramp input.
f. Using Xcos of Scilab, plot the system response to unit step input before and after
the compensation.
1/s(s² +4s+5)
Fig. 1 System Block Diagram
Output
Y(s)