WOLFRAM SYSTEMMODELER

VariableLimiter

Limit the range of a signal with variable limits

Wolfram Language

In[1]:=
SystemModel["Modelica.Blocks.Nonlinear.VariableLimiter"]
Out[1]:=

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

The Limiter block passes its input signal as output signal as long as the input is within the upper and lower limits specified by the two additional inputs limit1 and limit2. If this is not the case, the corresponding limit is passed as output.

The parameter homotopyType in the Advanced tab specifies the simplified behaviour if homotopy-based initialization is used:

  • NoHomotopy: the actual expression with limits is used
  • Linear: a linear behaviour y = u is assumed (default option)
  • Fixed: it is assumed that the output is fixed at the value ySimplified

If it is known a priori in which region the input signal will be located, this option can help a lot by removing one strong nonlinearity from the initialization problem.

Parameters (4)

strict

Value: false

Type: Boolean

Description: = true, if strict limits with noEvent(..)

homotopyType

Value: Modelica.Blocks.Types.VariableLimiterHomotopy.Linear

Type: VariableLimiterHomotopy

Description: Simplified model for homotopy-based initialization

ySimplified

Value: 0

Type: Real

Description: Fixed value of output in simplified model

limitsAtInit

Value: true

Type: Boolean

Description: Has no longer an effect and is only kept for backwards compatibility (the implementation uses now the homotopy operator)

Connectors (4)

u

Type: RealInput

Description: Connector of Real input signal

y

Type: RealOutput

Description: Connector of Real output signal

limit1

Type: RealInput

Description: Connector of Real input signal used as maximum of input u

limit2

Type: RealInput

Description: Connector of Real input signal used as minimum of input u

Used in Components (2)

LimitedPI

Modelica.Electrical.Machines.Examples.ControlledDCDrives.Utilities

Limited PI-controller with anti-windup and feed-forward

DcdcInverter

Modelica.Electrical.Machines.Examples.ControlledDCDrives.Utilities

DC-DC inverter