Assignment
Show all required calculations, MATLAB code and MATLAB plots for full credit.
1. A u nity feedback control system has a loop transfer function:
Gc(s)G(s) = K / ((1 + s/4)(1 + s)(1 + s/20)(1 + s/80))
where K = 10. Use MATLAB to obtain the Bode diagram of this system.
1. A closed-loop system has a loop transfer function:
L(s) = Gc(s)G(s) = K / (s(s + 8)(s + 12))
1. Determine the gain K so that the phase margin is 60 degree.
2. For the gain K selected in part (a) determine the gain margin of the system.
2. An uncompensated control system with unity feedback has a plant transfer function:
G(s) = K / (s(s/2 + 1)(s/6 + 1))
We want to have a velocity error constant of Kv = 20. We also want to have a phase margin of approximately 45 degrees and a closed-loop bandwidth greater than ω = 4 rad/s. Use two identical cascaded phase-lead networks to compensate the system.
1. The transfer function of a plant and a zero-order system shown below is
G(z) = K(z + 0.5) / (z(z - 1))
1. Use MATLAB to plot the root locus.
2. Determine the rang e of gain K for a stable system.