Page 573 - Basic Electrical Engineering

or,

Again,

E = 4.44 ϕ f N 1
1
m
= 4.44 B A f N 1
m

when B is the maximum flux density and A is the cross-sectional area of the
m
core.

Substituting values

Example 6.3 A 110 V/220 V transformer is supplied with 110 V, 50 Hz
supply to its low-voltage side. It is desired to have maximum value of core

flux as 4.2 mWbs. Calculate the required number of turns in its primary
winding.

Solution:

V = 110 V. Neglecting the winding voltage drop under no-load condition,
1
V = E = 110 V.
1
1

E = 4.44 ϕ ϕ N 1
1
m

−3
Substituting values, 110 = 4.44 × 4.2 × 10 × 50 × N 1