modelTestPID

Test of the 2DoF digital PID controller

Extends from Modelica.Icons.Example (Icon for runnable examples).

Information

Description

In this example have been tested the functionalities of the 2DoF incremental PID.
The PID has to control the process with transfer function

   Y(s)             5*s +1
   ----  =  -----------------------
   U(s)        20*s^2 + 12*s + 1

The image compares the outputs of the process y with and without the controller action.

Functionalities

In the following figure are shown the functionalities of the block. At the beginning the process variable
does not grows because the Finc signal that forbid the CS increment is true.
At t = 15 it becomes false and the PID start to act on the process, leading the PV to the Set Point desidered value.

At t = 40 the TS signal becomes true and it is maintained until t = 130. In such a period the
Control signal follows the TR one (the green one). To note that at the end the transition between Tracking and Automatic mode
is bumpless.
Between t = 200 and t = 300, the PID manual mode is enabled. In this phase the Control Signal varies according to the CSinc signal (see figure below).

Components

Type	Name	Default	Description
Modelica.Blocks.Sources.Step	step
IndustrialControlSystems.Controllers.Digital.PID_2dof	Controller
LinearSystems.Continuous.TransferFunction	Process
Modelica.Blocks.Sources.BooleanTable	TSsignal
Modelica.Blocks.Sources.TimeTable	TrackRef
Modelica.Blocks.Math.Feedback	sub
Modelica.Blocks.Sources.Step	disturb
Modelica.Blocks.Sources.BooleanTable	ForbinINC
Modelica.Blocks.Sources.BooleanTable	ForbinDEC
Modelica.Blocks.Sources.BooleanTable	man
Modelica.Blocks.Sources.TimeTable	deltaCS
LinearSystems.Continuous.TransferFunction	ProcessNoControl

Revisions

Industrial Control Systems (v 1.0.0) : April-May 2012