Winding

Purpose

Ideal winding defining an electro-magnetic interface

Library

Magnetic / Sources

Description

../../_images/magneticinterface.svg

The Winding forms the interface between the electrical and the magnetic domain. A winding of \(N\) turns is described with the equations:

\[v = N \, \dot{\Phi}\]
\[i = \frac{\mathcal{F}}{N}\]

where \(v\) and \(i\) are voltage and current at the electrical terminals. \(\mathcal{F}\) is the magneto-motive force (MMF) and \(\dot{\Phi}\) is the rate-of-change of the magnetic flux through the winding. The left-hand side of the equations above refers to the electrical domain, the right-hand side to the magnetic domain.

The sign conventions used for the electrical and magnetic quantities are illustrated in Fig. 280 for the two polarities of the winding. Notice the positions of the black dot and the brown arrow in the winding symbol.

../../_images/winding_schema.svg

Fig. 280 Sign conventions used for electrical and magnetic quantities

Parameters

Number of turns

Specifies the number of winding turns.

Polarity

Specifies the polarity of the winding. Choosing a negative polarity is equivalent to specifying a negative number of turns.

Probe Signals

Winding voltage

The voltage measured from the positive (marked) to the negative electrical terminal of the winding, in volts (\(\mathrm{V}\)).

Winding current

The current flowing through the winding, in amperes (\(\mathrm{A}\)). A current entering the winding at the marked terminal is counted as positive.

MMF

The magneto-motive force measured from the marked to the unmarked magnetic terminal, in ampere-turns (\(\mathrm{A}\)).