Toroid

Toroid with circular cross section; fixed shape; linear or non-linear material characteristics

Information

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

Please refer to the enclosing sub-package FixedShape for a description of all elements of this package and to [Ro41] for derivation and/or coefficients of the equation for permeance G_m.

For toroidal flux tubes with a circumferential magnetic flux, the flux density is a function of the radius. For that reason, the characteristic mu_r(B) is evaluated for the flux density at the flux tube's mean radius.

For those flux tube sections of a magnetic device that have a nonlinear material characteristic mu_r(B) and a large aspect ratio of outer to inner radius r_o/r_i, the section can be split up in a series connection of several hollow cylindrical flux tubes with radial flux. This allows for more realistic modelling of the dependence of flux density on the radius compared to modelling with just one flux tube element.

Parameters (6)

nonLinearPermeability

Value: true

Type: Boolean

Description: = true, if non-linear rel. permeability is used, otherwise constant rel. permeability

mu_rConst

Value: 1

Type: RelativePermeability

Description: Constant relative permeability; used if nonLinearPermeability = false

material

Value: Material.SoftMagnetic.BaseData()

Type: BaseData

Description: Ferromagnetic material characteristics; used if nonLinearPermeability = true

r

Value: 0.1

Type: Radius (m)

Description: Radius of toroid (middle)

d

Value: 0.01

Type: Radius (m)

Description: Diameter of cylindrical core

alpha

Value: pi / 2

Type: Angle (rad)

Description: Angle of toroid section

Connectors (2)

port_p

Type: PositiveMagneticPort

Description: Positive magnetic port

port_n

Type: NegativeMagneticPort

Description: Negative magnetic port

Components (1)

material

Type: BaseData

Description: Ferromagnetic material characteristics; used if nonLinearPermeability = true

Used in Examples (1)

ToroidalCoreAirgap

Modelica.Magnetic.FluxTubes.Examples.BasicExamples

Educational example: iron core with airgap