3 pid controller – YSI IQ S ENSOR N ET DIQ/S 182 XT User Manual
Page 123
System 182
Outputs
6 - 27
ba76022e01
12/2011
6.5.3
PID controller
Function
With the PID controller function, you can use an output as a controller
output. The controller can be configured as a Proportional controller
with a switchable Integral and Derivative controller part (PID controller).
The control mode of the PID controller is described by the following
equation:
with:
The adjustable control parameters are x
nominal
, I
0
, X
p
, I
min
, I
max
, ti
and T
d
(see setting table on page 6-30).
I
Controller
Current at the controller output at time t
I
0
Current at output if x
actual
= x
nominal
K
Gain
X
p
Proportional band
x
e
Error signal
x
actual
Actual value (current measured value)
x
nom
Nominal value
ti
Integral control part
td
Derivative control part
t
Time
I
min
Lower current limitation
I
max
Upper current limitation
+
+
+
=
dt
dx
T
dt
x
T
1
x
K
I
I
e
d
e
i
e
0
Controller
p
min
max
X
I
I
K
−
=
actual
nom
e
x
x
x
−
=
max
Controller
min
I
I
I
≤
≤