YOKOGAWA UTAdvanced UT55A, Руководство пользователя

Страница: 216 / 476

8-87
IM 05P01C31-01EN
Control Functions
8.3 Setting PID Control Mode (ALG)
Description
There are two PID control modes: standard PID control mode and fixed-point control
mode.
Select a PID control computation formula shown in the following table according to the
control mode or operation mode.
Single-loop Control, Loop Control for Backup, Loop Control with PV Switching, Loop
Control with PV Auto-selector, and Loop Control with PV-hold Function.
Operation mode
AUTO+Local AUTO+Remote
Standard PID control
mode
PV derivative type
(output bump at SP change)
Deviation derivative type
Fixed-point control
mode
PV derivative type
(output bumpless at SP change)
PV derivative type
(output bump at SP change)
Cascade Primary-loop Control
Operation mode
Local Remote
Standard PID control
mode
PV derivative type
(output bump at SP change)
Deviation derivative type
Fixed-point control
mode
PV derivative type
(output bump at SP change)
PV derivative type
(output bump at SP change)
Cascade Secondary-loop Control
Operation mode
AUTO+Local AUTO+Remote Cascade
Standard PID control
mode
PV derivative type
(output bump at SP change) Deviation derivative type Deviation derivative type
Fixed-point control
mode
PV derivative type
(output bumpless at SP change)
PV derivative type
(output bump at SP change)
PV derivative type
(output bump at SP change)
PV Derivative Type PID
This is a PID control method in which the derivative action works only on the PV.
It can also eliminate output bump due to SP changing operation in Local mode.
The following shows the PV derivative type PID control computation formula.
e e
P
OUT
+ + dt Td ΔPV
= 100
Ti
1
dt
d
∫






• •
where OUT: control output, e: deviation (PV-SP), P: proportional band, Ti: integral time,
Td: derivative time, and ∆PV: PVn-PVn-1 (n-1: value before one control period)
PV Derivative Type PID (output bump at SP change)
SP
PV OUT
8