blockSequenceControl

Model of a sequence control function

Extends from Modelica.Blocks.Interfaces.SISO (Single Input Single Output continuous control block).

Information

Overview

This model allows to implement a sequence control often deployed in building automation systems. A sequence control is used to implement for example that a heating coil valve of an air handling unit may only be opened when the respective cooling coil valve is closed. We model each sequence of a sequence control as a set of three linear curves defined on their intervals. The first curves interval ranges from -inf to xCooLHS, the second interval ranges from xCooLHS to xCooRHS and the third interval from xCooRHS to +inf.

Assumptions

We assume that only linear functions occur. One sequence control may be composed out of several sequences spanning with nCurves.

Parameterisation

To parameterise multiple sequences we use a multidimensional array which should be used as follows:

CurvesIntervalCoordinates[nCurves,2,2] = {
{{xCooLHS_1,yCooLHS_1},{xCooRHS_1,yCooRHS_1}},
{{xCooLHS_2,yCooLHS_2},{xCooRHS_2,yCooRHS_2}},
...
{{xCooLHS_nCurves,yCooLHS_nCurves},{xCooRHS_1,yCooRHS_nCurves}},
}

where

xCooLHS_n - X-coordinate of left hand side interval of the n-th curve
yCooLHS_n - Y-coordinate of left hand side interval of the n-th curve
xCooRHS_n - X-coordinate of right hand side interval of the n-th curve
yCooRHS_n - Y-coordinate of right hand side interval of the n-th curve

Parameters

TypeNameDefaultDescription
IntegernCurves2Number of curves in sequence control
Real[nCurves,2,2]CurvesIntervalCoordinates{{{16, 100}, {19, 0}}, {{23, 0}, {26, 100}}}Parameter array to specify interval coordinates left hand side and right hand side point

Connectors

TypeNameDefaultDescription
RealInputu (from SISO)Connector of Real input signal
RealOutputy (from SISO)Connector of Real output signal

Components

TypeNameDefaultDescription
Internal.Limiter[nCurves]CurvesArray of curves in sequence control
Modelica.Blocks.Math.MultiSummultiSumAggregate output signals of all curves

Revisions

  • March 07, 2017  by Georg Ferdinand Schneider & Georg Ambrosius Peßler:
    Implemented.