modelEddyCurrent
Extends from Interfaces.TwoPort (Interface component including flux balance equation), Modelica.Electrical.Analog.Interfaces.ConditionalHeatPort (Partial model to include a conditional HeatPort in order to describe the power loss via a thermal network).
Information
Eddy currents are induced in a conductive magnetic flux tube when the flux changes with time. This causes a magnetic voltage drop in addition to the voltage drop that is due to the reluctance of this flux tube. The eddy current component can be thought of as a short-circuited secondary winding of a transformer with only one turn. Its resistance is calculated from the geometry and resistivity of the eddy current path.
Partitioning of a solid conductive cylinder or prism into several hollow cylinders or separate nested prisms and modelling of each of these flux tubes connected in parallel with a series connection of a reluctance element and an eddy current component can model the delayed buildup of the magnetic field in the complete flux tube from the outer to the inner sections. Please refer to [Ka08] for an illustration.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | useHeatPort (from ConditionalHeatPort) | false | = true, if heatPort is enabled |
| SI.Temperature | T (from ConditionalHeatPort) | 293.15 | Fixed device temperature if useHeatPort = false |
| Boolean | useConductance | false | Use conductance instead of geometry data and rho |
| SI.Conductance | G | 1/0.098e-6 | Equivalent loss conductance G=A/rho/l |
| SI.Resistivity | rho | 0.098e-6 | Resistivity of flux tube material (default: Iron at 20degC) |
| SI.Length | l | 1 | Average length of eddy current path |
| SI.Area | A | 1 | Cross sectional area of eddy current path |
| SI.Resistance | R | rho*l/A | Electrical resistance of eddy current path |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| FluxTubes.Interfaces.PositiveMagneticPort | port_p (from TwoPortElementary) | Positive magnetic port | |
| FluxTubes.Interfaces.NegativeMagneticPort | port_n (from TwoPortElementary) | Negative magnetic port | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | heatPort (from ConditionalHeatPort) | Conditional heat port |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| SI.MagneticPotentialDifference | V_m (from TwoPortExtended) | Magnetic potential difference of ports | |
| SI.MagneticFlux | Phi (from TwoPortExtended) | Magnetic flux from port_p to port_n | |
| SI.Power | LossPower (from ConditionalHeatPort) | Loss power leaving component via heatPort | |
| SI.Temperature | T_heatPort (from ConditionalHeatPort) | Temperature of heatPort |
Revisions
Version 3.2.2, 2014-01-15 (Christian Kral)
- Added parameter
useConductanceincluding alternative parameterization