Suppose that the gain, time constant and dead time of a process with the following transfer function:Gc(s) = 10 exp( - 0.1s)/(0.5s + 1) are known with a possible error of ± 20% of their values. The largest permissible gain Kc of a proportional controller needs to be calculated below taking the values of process gain, time constant and dead time as
A. 8, 0.6, 0.08
B. 12, 0.6, 0.12
C. 8, 0.6, 0.12
D. 12, 0.4, 0.08
Answer: Option B
This Question Belongs to Chemical Engineering >> Process Control And Instrumentation
Here dead time e-0.1s
Kc = 10 , possible error is 20% so, kc will be 10 + 20% of 10 = 12
Time constant is 0.5, new time constant will be 0.5 + 20% of 0.5 = 0.6
Dead time is 0.1 , new dead time is 0.1 + 20% of 0.1 = 0.12
Answer: b) 12, 0.6, 0.12