modelVariableOrder

Inertia using a critical damper with variable order

Extends from BaseClasses.PartialInertia (Partial inertia model).

Information

Model that uses a variable order delay to account for inertia.

Following the associated publication by Wuellhorst et al. (2021), this model was used to calibrate the heat pump model. If first order is selected, the frequency refIneFreConst equals the inverse of the time constant of a first order delay element.

In usage, be careful with the order of the delay. While a second or third order delay may result in a better fit in calibration, simulation speed is impacted. See the discussion in the paper for more information: https://doi.org/10.3384/ecp21181561

Parameters

TypeNameDefaultDescription
Modelica.Blocks.Types.InitinitTypeModelica.Blocks.Types.Init.NoInitType of initialization (1: no init, 2: steady state, 3: initial state, 4: initial output)
Refrigerant inertia
Modelica.Units.SI.FrequencyrefIneFreConstCut off frequency for inertia of refrigerant cycle
IntegernthOrd1Order of refrigerant cycle interia
Initialization › Refrigerant inertia
Real[nthOrd]x_startzeros(nthOrd)Initial or guess values of states
RealyRefIne_start0Initial or guess value of output (= state)

Connectors

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

Components

TypeNameDefaultDescription
Modelica.Blocks.Continuous.CriticalDampingcriDamVariable order damping model

Revisions

  • October 2, 2022 by Fabian Wuellhorst:
    First implementation (see issue #1576)