modelEddyCurrentForce

Simple model of a translational eddy current brake

Extends from Modelica.Mechanics.Translational.Interfaces.PartialForce (Partial model of a force acting at the flange (accelerates the flange)), Modelica.Thermal.HeatTransfer.Interfaces.PartialElementaryConditionalHeatPort (Partial model to include a conditional HeatPort in order to dissipate losses, used for textual modeling, i.e., for elementary models).

Information

This is a simple model of a translational eddy current brake. The force versus speed characteristic is defined by Kloss' equation.

The influence of excitation is either constant (useExcitationInput=false) or given by the optional input excitation (useExcitationInput=true). Note that maximum force depends on square of excitation (magnetic field).

Thermal behaviour:
The resistance of the braking fin is influenced by the actual temperature Theatport, which in turn shifts the speed v_nominal at which the (unchanged) maximum torque occurs.
If the heatPort is not used (useHeatPort = false), the operational temperature remains at the given temperature T.
However, the speed v_nominal at which the maximum torque occurs is adapted from reference temperature TRef to the operational temperature.

Parameters

TypeNameDefaultDescription
BooleanuseExcitationInputfalseEnable signal input for excitation
RealconstantExcitation1Excitation=1 to reach maximum force
SI.Forcef_nominalConstant maximum force (always braking)
SI.Velocityv_nominalNominal speed (leads to maximum force) at reference temperature
SI.TemperatureTRefReference temperature
Modelica.Electrical.Machines.Thermal.LinearTemperatureCoefficient20alpha20Temperature coefficient of material
BooleanuseSupport (from PartialElementaryOneFlangeAndSupport2)false= true, if support flange enabled, otherwise implicitly grounded
BooleanuseHeatPort (from PartialElementaryConditionalHeatPort)false= true, if heatPort is enabled
SI.TemperatureT (from PartialElementaryConditionalHeatPort)293.15Fixed device temperature if useHeatPort = false

Connectors

TypeNameDefaultDescription
Flange_bflange (from PartialElementaryOneFlangeAndSupport2)Flange of component
Supportsupport (from PartialElementaryOneFlangeAndSupport2)Support/housing of component
HeatTransfer.Interfaces.HeatPort_aheatPort (from PartialElementaryConditionalHeatPort)Optional port to which dissipated losses are transported in form of heat
Blocks.Interfaces.RealInputexcitationexcitationInternalExcitation

Components

TypeNameDefaultDescription
SI.Lengths (from PartialElementaryOneFlangeAndSupport2)Distance between flange and support (= flange.s - support.s)
SI.Forcef (from PartialForce)Accelerating force acting at flange (= flange.f)
SI.PowerlossPower (from PartialElementaryConditionalHeatPort)Loss power leaving component via heatPort (> 0, if heat is flowing out of component)
SI.TemperatureTheatPort (from PartialElementaryConditionalHeatPort)Temperature of heatPort
SI.VelocityvVelocity of flange with respect to support (= der(s))
Realv_normalizedRelative speed v/v_nominal