MMF source

A constant magnetomotive force (for example a permanent magnet model).

  • magnetic
  • Modelica Standard Library
  • 2 ports
  • 1 parameter
BlockMMF sourceKindmmfSourceLibraryMagnetic

Description

A constant magnetomotive force between its ports, whatever flux passes through. Use it for an idealized coil with fixed ampere-turns or, with a series reluctance, a simple permanent-magnet model.

Example

Magnetic circuits A 100-turn winding drives flux through an air gap and a core, next to magnetic sources and a variable reluctance.

1 VGroundR 1 ΩWinding 100 turnsCore fluxAir gapCoreMagnetic groundGap mmfmmf 100 AGround (mmf)R_m signalVariable reluctanceFlux (variable)Ground (variable)50 ASignal mmfGround (signal)Permeance 1 µWb/AFlux (permeance)Ground (permeance)Flux 1 mWbGround (flux)Reluctance 10⁶mmf acrossGround (reluctance)
In Gradara, select a MMF source block and press F1, then choose Open example. It opens as a new model in My models, ready to run.

Also in this example:DC voltageStepGroundSine waveResistorReluctancePermeanceVariable reluctanceWindingMagnetic groundControlled MMF sourceFlux sourceFlux sensorMMF sensor

Ports

Conserving terminals 2

  • +port_pmagnetic

    Positive magnetic port, held V_m above port_n.

  • −port_nmagnetic

    Negative magnetic port.

Parameters

  • Magnetomotive forceV_m100 A

    Magnetomotive force, in amperes (ampere-turns). Any real value.

Equations

Modelica
port_p.V_m − port_n.V_m = V_m
port_p.Φ + port_n.Φ = 0

Implementation

Modelica Standard Library 4.1.0Modelica.Magnetic.FluxTubes.Sources.ConstantMagneticPotentialDifference
MSL documentation

Assumptions and limitations

  • An ideal source: no internal reluctance. Connect a reluctance in series to model a magnet’s own reluctance.

See also

Select a block in Gradara and press F1 to open its page offline.