1. Problem 04-01
Homework-04
In the control system shown in the figure Gp and Gc are given as Gp(s)=(2s+3)/(s3+6s2-28s) and Gc=K.
a) Is the system stable for K=100.
b) What is the value of the steady-state error for the parabolic input If the control gain is K=80.
Problem 04-02
Kuo 6-9. (P.355)
The block diagram of the dc-motor control system with tacometer feedback is shown in the figure. Find the range of the tachometer constant Kt so that the system is asymtotically stable.
Answer :

2. Problem 04-03
Thompson (p. 131)
Find the tranfer funtion of PID controller for the closed loop system using the Ziegler-Nichols method. Write the MATLAB program for the step response.
Answer:
Problem 04-04
If the control gain of a closed loop system is greater than 36.8, the system is unstable. In this crital gain, the poles are found as -2.4, ±1.8i, -1±3.6i. Find the tranfer funtion of PI controller for the closed loop system using the Ziegler-Nichols method.
Problem 04-05
Consider Example 4.2. Compare the results by plotting the step responses of the closed loop system for P, PI and PID control.