Omron CS1W-LC001 Operation Manual page 188

Examples of Applied Control Types
Note 2 By dead time compensation control, dead time compensation is performed on
MV as shown below and the result is added to the PV of PID control.
Set Point
−
As dead time L worsens controllability, control is performed on process
K/(1+Ts) not having dead time element (
element within the PC.
+
Set Point
The Dead Time Compensation block (Block Model 149) inputs MV for
Á
-Ls
K (1-( )
e
Advanced PID block (Block Model 012). The PV compensation mode is set to
"add". The Dead Time Compensation block (Block Model 149) sets K
(process gain), T (time constant of process) and L (dead time) to equal H
(sampling cycle) multiplied by N (number of samples). Set MV to manual,
apply step changes to the process, and calculate these constants from the
changes in PV.
+
PID control
+
Dead tim e
+
com pens ation
PV
PID control
−
+
K (1-e
1+Ts
+
PV
(1+Ts), and outputs the result to ITEM047 (PV compensation) of
1
K
L (dead time)
Dis turbance
+
characteristics
+
-Ls
) by compensating the dead time
e
Disturbance
+
Ke
1+Ts
+
-Ls
)
K × 0.632
T (time constant)
Section 5-2
Control
output
Process
Control
output
-Ls
171