Buildings.Fluid.Actuators.Motors

Package with motor models for valves and dampers

Information


This package contains components models for motors that may be
used with the actuator models in
Buildings.Fluid.Actuators.Dampers
or
Buildings.Fluid.Actuators.Valves.

Package Content

NameDescription
Buildings.Fluid.Actuators.Motors.IdealMotor IdealMotor Ideal motor model with hysteresis
Buildings.Fluid.Actuators.Motors.Examples Examples Collection of models that illustrate model use and test models


Buildings.Fluid.Actuators.Motors.IdealMotor Buildings.Fluid.Actuators.Motors.IdealMotor

Ideal motor model with hysteresis

Buildings.Fluid.Actuators.Motors.IdealMotor

Information


Ideal actuator motor model with hysteresis and finite actuation speed.
If the current actuator position y is below (or above) the
input signal u by an amount bigger than the hysteresis
delta, then the position y is increased (decreased)
until it reaches u.
The output y is bounded between 0 and 1.

Note: This model can introduce state events which increase the computation time.

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

Parameters

TypeNameDefaultDescription
Realdelta0.05Hysteresis
TimetOpe120Opening time [s]
TimetClotOpeClosing time [s]
Realy_start0.5Start position

Connectors

TypeNameDescription
input RealInputuConnector of Real input signal
output RealOutputyConnector of Real output signal

Modelica definition

model IdealMotor "Ideal motor model with hysteresis"
  extends Modelica.Blocks.Interfaces.SISO;

  parameter Real delta(min=0, max=0.5) = 0.05 "Hysteresis";
  parameter Modelica.SIunits.Time tOpe(min=0) = 120 "Opening time";
  parameter Modelica.SIunits.Time tClo(min=0) = tOpe "Closing time";
  parameter Real y_start(min=0, max=1) = 0.5 "Start position";

  Modelica.Blocks.Logical.Hysteresis uppHys(final uLow=0, uHigh=delta,
    final pre_y_start=false);
  Modelica.Blocks.Logical.Hysteresis lowHys(uLow=-delta, final uHigh=0,
    final pre_y_start=true) "Lower hysteresis";
  Modelica.Blocks.Logical.Switch uppSwi;
  Modelica.Blocks.Continuous.LimIntegrator int(
    final y_start=y_start,
    final k=1,
    outMax=1,
    outMin=0,
    initType=Modelica.Blocks.Types.Init.InitialState,
    limitsAtInit=true,
    y(stateSelect=StateSelect.always)) "Integrator for valve opening position";

protected 
  final Modelica.Blocks.Sources.Constant zer(final k=0) "Zero signal";
  Modelica.Blocks.Sources.Constant vOpe(final k=1/tOpe) "Opening speed";
  Modelica.Blocks.Sources.Constant vClo(final k=-1/tClo) "Closing speed";
  Modelica.Blocks.Logical.Switch lowSwi;
  Modelica.Blocks.Math.Add add;
  Modelica.Blocks.Math.Feedback feeBac "Feedback to compute position error";
equation 
  connect(zer.y, uppSwi.u3);
  connect(uppHys.y, uppSwi.u2);
  connect(vOpe.y, uppSwi.u1);
  connect(lowHys.y, lowSwi.u2);
  connect(vClo.y, lowSwi.u3);
  connect(zer.y, lowSwi.u1);
  connect(add.y, int.u);
  connect(uppSwi.y, add.u1);
  connect(u, feeBac.u1);
  connect(feeBac.y, uppHys.u);
  connect(feeBac.y, lowHys.u);
  connect(lowSwi.y, add.u2);
  connect(int.y, y);
  connect(int.y, feeBac.u2);
end IdealMotor;

HTML-documentation generated by Dymola Mon Jun 14 14:27:45 2010.