Emerson PACMotion VFD Series - PID Control Parameters; Parameter Group 3 - PID Control Overview

GFK-3111A PACMotion VFD AC Variable Speed Drive User Guide 61
Parameter Group 3 – PID Control
Overview
PACMotion VFD provides an internal PID controller. Parameters for conguration of the PID controller are
located together in Group 3. For simple applications, the user needs to only dene the setpoint source (P3-05
to select the source or P3-06 for a xed setpoint), feedback source (P3-10) and adjust the P Gain (P3-01),
I time (P3-02) and optionally the differential time (P3-03).
The PID operation is uni-directional, and all signals are treated as 0 – 100% to provide a simple, intuitive
operating format.
Table 37: Parameter Group 3 – PID Control
Par Parameter Name Minimum Maximum Default Units
P3-01 PID proportional gain 0.0 30.0 1.0 -
PID Controller Proportional Gain. Higher values provide a greater change in the drive output frequency in
response to small changes in the feedback signal. Too high a value can cause instability.
P3-02 PID integral time 0.0 30.0 1.0 s
PID Controller Integral Time. Larger values provide a more damped response for systems where the overall
process responds slowly.
P3-03 PID differential time 0.00 1.00 0.00 s
PID Differential Time Constant.
P3-04 PID operating mode 0 1 0 -
0 Direct Use this mode if an increase in the motor speed should result in an
increase in the feedback signal.
1 Inverse Use this mode if an increase in the motor speed should result in a
decrease in the feedback signal.
P3-05 PID reference select 0 2 0 -
0 Digital preset P3-06 is used.
1 Analog Input 1 Analog Input 1 as displayed in P0-01 is used.
2 Analog Input 2 Analog Input 2 as displayed in P0-02 is used.
P3-06 PID digital reference 0.0 100.0 0.0 %
When P3-05 = 0, this parameter sets the preset digital reference (setpoint) used for the PID Controller.
Where the feedback is provided from a transducer such as a pressure transducer or level measurement,
this represents the percentage of the pressure range (e.g. for a 0 – 10 Bar transducer, 4 bar = 40%) or the
level.
P3-07 PID output upper limit P3-08 100.0 100.0 %
Limits the maximum value output from the PID controller.
P3-08 PID output lower limit 0.0 P3-07 0.0 %
Limits the minimum output from the PID controller.
P3-09 PID output limit select 0 3 0 -
0 Digital Output Limits The output range of the PID controller is limited by the values of P3-07
& P3-08.
1 Upper limit set by analog
input 1
The output range of the PID controller is limited by the values of P3-08
& the signal applied to Analog Input 1.
2 Lower limit set by analog
input 1
The output range of the PID controller is limited by the signal applied to
Analog Input 1 & the value of P3-07.
3 PID output added to analog
input 1
The output value from the PID Controller is added to the speed
reference applied to the Analog Input 1.
P3-10 PID feedback select 0 5 0 -
0 Analog Input 2
1 Analog Input 1
2 Motor Current
3 DC Bus Voltage
4 Differential : Analog Input 1 – Analog Input 2
5 Largest Value : Analog Input 1 or Analog Input 2