Siemens SIMATIC S5 User Manual

S5-115F Manual Blocks
Correction Rate Algorithm
A particular correcting increment dY
k
is calculated at a particular instant t= k
•
TA according to
the following formula:
• Without feedforward injection of disturbance variable (D11.5 = 1) and application of XW to
the differentiator (D11.1 = 0)
dY
k
= K [(XW
k
- XW
k-1
) R+TI
•
XW
k
+ (TD (XW
k
- 2XW
k-1
+ XW
k-2
) + dD
k-1
)]
= K (dPW
k
R + dI
k
+ dD
k
)
• With feedforward injection of disturbance variable (D11.5 = 0) and application of XW to the
differentiator (D11.1 = 0)
dY
k
= K [(XW
k
- XW
k-1
) R+TI
•
XW
k
+ (TD (XW
k
- 2XW
k-1
+ XW
k-2
) + dD
k-1
)]+(Z
k
-Z
k-1
)
= K (dPW
k
R + dI
k
+ dD
k
)+dZ
k
• Without feedforward injection of disturbance variable (D11.5 = 1) and application of XZ to
the differentiator (D11.1 = 1)
dY
k
= K [(XW
k
- XW
k-1
) R+TI
•
XW
k
+ (TD (XZ
k
- 2XZ
k-1
+ XZ
k-2
) + dD
k-1
)]
= K (dPW
k
R + dI
k
+ dD
k
)
• With feedforward injection of disturbance variable (D11.5 = 0) and application of XZ to the
differentiator (D11.1 = 1)
dY
k
= K [(XW
k
- XW
k-1
) R+TI
•
XW
k
+ (TD (XZ
k
- 2XZ
k-1
+ XZ
k-2
) + dD
k-1
)]+(Z
k
-Z
k-1
)
= K (dPW
k
R + dI
k
+ dD
k
)+dZ
k
P component I component D component k: k
th
sampleZ component
When XW
k
is applied: XW
k
=W
k
- X
k
PW
k
=XW
k
- XW
k-1
QW
k
=PW
k
- PW
k-1
=XW
k
-2XW
k-1
+XW
k-2
When XZ is applied: PZ
k
=XZ
k
- XZ
k-1
QZ
k
=PZ
k
- PZ
k-1
=XZ
k
-2XZ
k-1
+XZ
k-2
The result is: dPW
k
= (XW
k
- XW
k-1
)R
dI
k
=TI
•
XW
k
dD
k
= (TD
•
QW
k
+dD
k-1
) with XW application
= (TD
•
QZ
k
+dD
k-1
) with XZ application
dZ
k
=Z
k
- Z
k-1
Correction Algorithm
The same algorithm is used for the correction algorithm as for the correction rate algorithm.
The difference compared with the correction rate algorithm is that, at the sampling point t
k
, the
sum of all control increments dY
k
calculated up to this point is output (in DW 48) instead of the
correcting increment calculated at this instant.
At the instant t
k
, manipulated variable Y
k
is calculated as follows:
m=k
Y
k
= dY
m
m=0
EWA 4NEB 811 6149-02 6-17

Siemens SIMATIC S5 Specifications

General

Product type designation	SIMATIC S5
Programming language	STEP 5
Digital inputs	Varies by model
Digital outputs	Varies by model
Analog inputs	Varies by model
Analog outputs	Varies by model
Supply voltage	24V DC
CPU Type	Varies by model
Memory	Varies by model
Digital I/O	Varies by model
Analog I/O	Varies by model
Communication	PROFIBUS
Operating Temperature	0°C to 60°C
Relative Humidity	5% to 95% (non-condensing)