10 PID CONTROL INSTRUCTIONS
10.2 PID Control Instructions (Inexact Differential)
1159
10
• Operational expressions
The meaning of the symbols in the operational expressions is as follows.
The PV
fn
is calculated by using the following operational expression. If the filter coefficient is not set to the input data, the PV
fn
will be same as the process value of the input data.
PV
fn
= PV
n
+
(PV
fn-1
- PV
n
)
PV
n
: Process value for the sampling period this time,
: Filter coefficient, PV
fn-1
: Process value for the sampling period last
time (after filtering)
PV
fn
is stored in the I/O data area. (
Action
Operational expression
Direct action
Reverse action
Symbol
Meaning
EV
n
Deviation in the sampling period this time
EV
n-1
Deviation in the sampling period last time
SV
Set value
PV
fn
Process value of the sampling period this time (after filtering)
PV
fn-1
Process value of the sampling period last time (after filtering)
PV
fn-2
Process value of the sampling period two times before (after filtering)
MV
Output variation amount
MV
n
Manipulated value this time
D
n
Derivative term this time
D
n-1
Derivative term of the sampling period last time
T
S
Sampling period
K
P
Proportional constant
T
I
Integral constant
T
D
Derivative constant
K
D
Derivative gain
EV
n
= PV
fn
-
SV
MV
n
= ΣΔMV
ΔMV = K
p
{(EV
n
- EV
n-1
) +
∙
EV
n
+ D
n
}
D
n
=
(PV
fn
- 2PV
fn-1
+ PV
fn-2
) +
T
I
T
S
T
S
+
K
D
T
D
T
D
T
S
+
K
D
T
D
K
D
T
D
∙
D
n-1
EV
n
= SV
-
PV
fn
MV
n
= ΣΔMV
ΔMV = K
p
{(EV
n
- EV
n-1
) +
∙
EV
n
+ D
n
}
D
n
=
( - PV
fn
+ 2PV
fn-1
- PV
fn-2
) +
T
I
T
S
T
S
+
K
D
T
D
T
D
T
S
+
K
D
T
D
K
D
T
D
∙
D
n-1
Содержание MELSEC iQ-R Series
Страница 1: ...MELSEC iQ R Programming Manual Instructions Standard Functions Function Blocks ...
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Страница 24: ...22 INDEX 2092 INSTRUCTION INDEX 2093 REVISIONS 2104 WARRANTY 2105 TRADEMARKS 2106 ...
Страница 34: ...32 MEMO ...
Страница 35: ...33 PART 1 PART 1 OVERVIEW This part consists of the following chapter 1 OVERVIEW ...
Страница 68: ...66 1 OVERVIEW 1 5 Precautions on Programming MEMO ...
Страница 204: ...202 5 SEQUENCE INSTRUCTIONS 5 3 Output Instructions Operation error There is no operation error ...
Страница 470: ...468 6 BASIC INSTRUCTIONS 6 6 Data Conversion Instructions Operation error There is no operation error ...
Страница 472: ...470 6 BASIC INSTRUCTIONS 6 6 Data Conversion Instructions Operation error There is no operation error ...
Страница 479: ...6 BASIC INSTRUCTIONS 6 6 Data Conversion Instructions 477 6 Operation error There is no operation error ...
Страница 504: ...502 6 BASIC INSTRUCTIONS 6 7 Data Transfer Instructions Operation error There is no operation error ...
Страница 518: ...516 6 BASIC INSTRUCTIONS 6 7 Data Transfer Instructions Operation error There is no operation error ...
Страница 520: ...518 6 BASIC INSTRUCTIONS 6 7 Data Transfer Instructions Operation error There is no operation error ...
Страница 754: ...752 7 APPLICATION INSTRUCTIONS 7 9 Real Number Instructions Operation error There is no operation error ...
Страница 756: ...754 7 APPLICATION INSTRUCTIONS 7 9 Real Number Instructions Operation error There is no operation error ...
Страница 758: ...756 7 APPLICATION INSTRUCTIONS 7 9 Real Number Instructions Operation error There is no operation error ...
Страница 760: ...758 7 APPLICATION INSTRUCTIONS 7 9 Real Number Instructions Operation error There is no operation error ...
Страница 895: ...7 APPLICATION INSTRUCTIONS 7 16 Ramp Signal Instruction 893 7 Operation error There is no operation error ...
Страница 917: ...7 APPLICATION INSTRUCTIONS 7 20 Data Processing Instructions 915 7 Operation error There is no operation error ...
Страница 919: ...7 APPLICATION INSTRUCTIONS 7 20 Data Processing Instructions 917 7 Operation error There is no operation error ...
Страница 1415: ...13 SFC PROGRAM INSTRUCTIONS 13 1 SFC Control Instructions 1413 13 Operation error There is no operation error ...
Страница 1448: ...1446 14 REDUNDANT SYSTEM INSTRUCTIONS 14 2 Disabling Enabling System Switching MEMO ...
Страница 1795: ...25 TYPE CONVERSION FUNCTIONS 25 1 Converting BOOL to WORD 1793 25 Operation error There is no operation error ...
Страница 1805: ...25 TYPE CONVERSION FUNCTIONS 25 10 Converting WORD to DINT 1803 25 Operation error There is no operation error ...
Страница 1819: ...25 TYPE CONVERSION FUNCTIONS 25 21 Converting INT to DWORD 1817 25 Operation error There is no operation error ...
Страница 1950: ...1948 32 STRING FUNCTIONS 32 2 Extracting String Data From the Left Right Operation error There is no operation error ...
Страница 1972: ...1970 33 TIME DATA TYPE FUNCTIONS 33 4 Division MEMO ...
Страница 2067: ...APPX Appendix 5 PID Control Program Examples 2065 A 252 Set PID control data for loop 2 ...
Страница 2082: ...2080 APPX Appendix 6 Process Control Program Examples 129 Set the default value of the loop tag ...
Страница 2093: ...APPX Appendix 7 List of Loop Tag Memory Areas Used by Process Control Instructions 2091 A MEMO ...
Страница 2109: ......