Answer to Question #261095 in Chemical Engineering for Shirisha

Question

The value of ultimate period of oscillation Pu is 3minutesand the ultimate control gain Kcu is 2,select correct set of parameters for PID controller using Zeigler-nicholas

Answer 1

K_p = 0.6K_u

τ_i = P_u/2

τ_d = P_u/8

K_p = Controller gain value that you should enter into the controller for good performance

K_u = “Ultimate” gain determined by increasing controller gain until self-sustaining oscillations are achieved

τ_i = Controller integral setting that you should enter into the controller for good performance (minutes per repeat)

τ_d = Controller derivative setting that you should enter into the controller for good performance (minutes)

P_u = “Ultimate” period of self-sustaining oscillations determined when the controller gain was set to K_u (minutes)

K_p = 0.6K_u = 0.6*2 = 1.2 minutes

τ_i = P_u/2 = 3/2 = 1.5 minutes per repeat

τ_d = P_u/8 = 3/8 = 0.375 minutes