Omron SYSMAC CJ - REFERENCE MANUAL 01-2008 Reference Manual page 802

Data Control Instructions
Execution
condition
Performance Specifications
Item
PID control method
Number of PID control loops
Sampling period
PID constant Proportional band
Integral constant
Derivative constant
Set value
Measured value
Manipulated variable
Calculation Method
Block Diagram for Target Value PID with Two Degrees of Freedom
Set value
(target value)
Measured
value (PV)
to FFFF hex for input to PID(190) and then the manipulated variable output
from PID(190) is converted back to the range 0000 to 1770 hex, again using
APR(069), for output from the Analog Output Unit.
From Analog Input Unit
ARP
D01000
Analog input value
D02000
PID
D02000
D02500
D03000
ARP
D01500
D03000
Analog output value
To Analog Output Unit
--- Target value filter-type two-degrees-of-freedom PID method (forward/
reverse)
--- Unlimited (1 loop per instruction)
0.01 to 99.99 s
P 0.1 to 999.9%
Tik 1 to 8191, 9999 (No integral action for sampling period multiple, 9999.)
Tdk 0 to 8191 (No derivative action for sampling period multiple, 0.)
SV 0 to 65535 (Valid up to maximum value of input range.)
PV 0 to 65535 (Valid up to maximum value of input range.)
MV 0 to 65535 (Valid up to maximum value of output range.)
Calculations in PID control are performed by the target value filtered control
with two degrees of freedom.
When overshooting is prevented with simple PID control, stabilization of dis-
turbances is slowed (1). If stabilization of disturbances is speeded up, on the
other hand, overshooting occurs and response toward the target value is
slowed (2).
When target-value PID control with two degrees of freedom is used, on the
other hand, there is no overshooting, and response toward the target value
and stabilization of disturbances can both be speeded up (3).
Target value filter
1 + (1 – ) Ti · s +
1 + Ti · s
–
Control Data
C (D01000):
C+1 (D01001):
C+2 (D01002):
C+3 (D01003):
C+4 (D01004):
Control Data
C+6 (D02506):
@8@8
Valid number of bits: 16 (0000 to FFFF Hex)
Valid number of bits: 16 (0000 to FFFF Hex)
Control Data
C (D01500):
C+1 (D01501):
C+2 (D01502):
C+3 (D01503):
C+4 (D01504):
Specifications
Proportional + integral elements
+
Kp
Kp +
Ti · s
–
Preceding derivative-
Kp: Proportional constant
type elements
Ti: Integral time
Td: Derivative time
Kp Td/ s
s: Laplace operator
.
1 + Td · s
: Incomplete derivative coefficient
Section 3-18
0000 Hex (binary with one table)
1770 Hex (Xm)
0000 Hex (Yo)
1770 Hex (X1)
FFFF Hex (Y1)
0000 Hex (binary with one table)
FFFF Hex (Xm)
0000 Hex (Yo)
FFFF Hex (X1)
1770 Hex (Y1)
Manipulated variable
: 2-PID parameter
763