TECO A510s - What Is PID Control?; Chapter 9 Using PID Control for Constant Flow; Pressure Applications

9-1
Chapter 9 Using PID Control for Constant Flow / Pressure
Applications
9.1 What is PID Control?
The PID function in the inverter can be used to maintain a constant process variable such as pressure,
flow, temperature by regulating the output frequency (motor speed). A feedback device (transducer)
signal is used to compare the actual process variable to a specified setpoint. The difference between
the set-point and feedback signal is called the error signal.
The PID control tries to minimize this error to maintain a constant process variable by regulating the
output frequency (motor speed).
×1
-1
10-09
10-24
10-03=xx0xb
10-03=xx1xb
(Bias)
+
+
(PID output gam)
PID Output
±200% Limit
+
10-03=1,2,5,6
10-03=3,4,7,8
10-25=0
10-25=1
+109%
+109%
-109%
+
+
PID=0N
Frequency
Reference
(Fref)
PID=OFF
10-04
10-07
10-05 10-06 10-10
+
Target
Value
Feedback
Value
(Feedback
Gain)
10-03=x0xxb
10-03=x1xxb
(D)
+
+
+
-
PID Input
(Deviation)
(P)
(I)
(D)
100%
-
100%
10-14
(I-Limit)
+
+
+
Integral Reset
(using Multi-function
Digital Input)
10-03=1,3,5,7
10-03=2,4,6,8
100%
-100%
(PID Limit)
10-23
(Primary
delay)
PID=OFF
1. 10-03=0 (PID Disabled)
2. during JOG mode
3. multi - function digital input
(03-00 – 03-07 setting = 29)
G23-04
10-00
10-01
10-07
The amplitude of the error can be adjusted with the Proportional Gain parameter 10-05 and is directly
related to the output of the PID controller, so the larger gain the larger the output correction.