
9-16 Power Electronics and Motor Drives
e determination of ε is not a problem when the iron permeability is supposed to be innite and the
eccentricity is neglected. e diculty consists in the determination of Λ. Approximate expressions
e
xist
f
or
a
l
ong
t
ime
i
n
t
he
l
iterature.
T
imar
[
2]
g
ives
a
n
e
xpression,
w
hich
n
eglects
t
he
i
nteractions
between stator and rotor slots. Alger [13] takes them into account by the mean of only one single term,
w
hich
c
orresponds
to
t
he
f
undamental
c
omponent.
I
t
h
as
b
een
s
hown
o
n
s
everal
o
ccasions
t
hat
c
ertain
eects, like the magnetic noise [18], are generally mainly tributary of higher-rank components that