Page 505 - Basic Electrical Engineering

Flux,

Example 5.4 A magnetic circuit is having its winding on its central limb.

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The cross-sectional area of the central limb is 10 cm whereas the cross-
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sectional area of the outer limbs is 5 cm . The effective length of the central
limb is 16 cm and that of the outer limbs is 25 cm. Calculate the current
required to flow through the winding which has 1000 turns to produce a flux

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of 1.2 mWb in the central limb. Assume that for a flux density of 1.2 Wb/m ,
the magnetizing force required is 750 AT/m. Draw the equivalent electric
circuit.

Solution:

The details of the magnetic circuit are shown in Fig. 5.23.

Figure 5.23

The equivalent electric circuit is drawn as shown in Fig. 5.24.