IndustrialControlSystems.Applications.ControlProblems.DecoupledControl

Example of decoupled control

Information


Description

The 2x2 process reported below has to be controlled



The process is controlled using a decoupler and two PIs ( R1(s) and R2(s) ), each one controlling the corresponding output signal.


The goal of the control system is to maintain the output of the processe as close as possible to the set point references,
avoiding the cross effects between the first input and the second output and vice versa.

The package contains two models in which the process has been controlled using the decoupler (see DecoupledControl ) and not (see NoDecoupledControl )

Process Variables and set point references without decoupler


Process Variables and set point references with decoupler


The images show how the different control schemes react to the set point changes. The decoupler based scheme performs better than the one without.

Extends from IndustrialControlSystems.Icons.ExamplesPackage (Examples package icon).

Package Content

NameDescription
IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.Process Process Two inputs Two outputs process Y1 = P11*u1 + P12*u2 and Y2 = P21*u1 + P22*u2
IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.Decoupler Decoupler Model of the 2x2 decoupler
IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.DecoupledControl DecoupledControl Control scheme with decoupler
IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.NoDecoupledControl NoDecoupledControl Control scheme without decoupler

IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.Process IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.Process

Two inputs Two outputs process Y1 = P11*u1 + P12*u2 and Y2 = P21*u1 + P22*u2

Information


  

Description

Two inputs two outputs process



The four transfer functions are defined via their numerators and denumerators.

Parameters

NameDescription
P11
P11_num[:] Transfer function num.
P11_den[:] Transfer function den.
P12
P12_num[:] Transfer function num.
P12_den[:] Transfer function den.
P21
P21_num[:] Transfer function num.
P21_den[:] Transfer function den.
P22
P22_num[:] Transfer function num.
P22_den[:] Transfer function den.

Connectors

NameDescription
u1input
u2input
y1output
y2output

IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.Decoupler IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.Decoupler

Model of the 2x2 decoupler

Information


  

Description

Decoupler for a two input two output process (see Process ).
The aim of the decoupler (represented in the following figure) is to reduce (ideally to delete them) the effects of the first input U1 on the second output Y2 and vice versa.
This can be done introducing the new variables (V1,V2) and placing the decoupler between them and the real process.


The decoupler is described by the following scheme (backward decoupler)


The effect of the decoupler is shown in the following picture where the decoupler with its backward action deletes the relation between V1 and Y2 (the sum of the blue and red paths).


Once the process is known (P11,P21,P21,P22), the decoupler can be specified by the definition of the two rational trasfer functions

  P12(s)
  ------ 
  P11(s)
  
and
  P21(s)
  ------
  P22(s)
  

N.B. If the transfer functions have more zeroes than poles or have instable poles have to be carefully modified.

Parameters

NameDescription
P_21_22
P_21_22_num[:] Transfer function num.
P_21_22_den[:] Transfer function den.
P_12_11
P_12_11_num[:] Transfer function num.
P_12_11_den[:] Transfer function den.

Connectors

NameDescription
u1input
u2input
y1output
y2output
toU1output
toU2output

IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.DecoupledControl IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.DecoupledControl

Control scheme with decoupler

Information


Description

The 2x2 process reported below has to be controlled



The process is controlled using a decoupler and two PIs ( R1(s) and R2(s) ), each one controlling the corresponding output signal.


The goal of the control system is to maintain the output of the processe as close as possible to the set point references,
avoiding the cross effects between the first input and the second output and vice versa.

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

IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.NoDecoupledControl IndustrialControlSystems.Applications.ControlProblems.DecoupledControl.NoDecoupledControl

Control scheme without decoupler

Information


Description

The 2x2 process reported below has to be controlled



The process is controlled using two PIs ( R1(s) and R2(s) ), each one controlling the corresponding output signal.


The goal of the control system is to maintain the output of the processe as close as possible to the set point references,
avoiding the cross effects between the first input and the second output and vice versa.

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

Automatically generated Mon May 21 13:34:17 2012.