A certain industrial process is arranged in a unit-feedback configuration with p

Question

A certain industrial process is arranged in a unit-feedback configuration with proportional controller. When the controller gain reaches a value of 3, the system becomes marginally stable. The system unit step response is shown in Figure 1. Determine the proportional-integral Derivative, PID, controller parameters using the Zeigler-Nichols ultimate sensitivity method (method II). You should find kp, ki and ka and write the controller, D(s), transfer function. 1.4r 1.2 0.8 0.6 0.4 0.2 10 20 30 40 50 60 Time [sec Figure1 Unit step response using gain of 3 for Problem 1

Explanation / Answer

PID control parameters using Ziegler-Nichols tuning method are given below.

Kp = 0.6Ku

Ti = Pu/2 and

Td = Pu/8

Where Ku is ultimate gain : 3 (given)

Pu : period of oscillation : 13 seconds (Approximately from the figure)

Therefore Kp = 0.6*3 = 1.8  

Ti = 13/2 = 6.5

Td = 13/8 = 1.625

Therefore D(s) = 1.8*(1+1/6.5s+1.625s) =

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.