Shark -new motor design concept for energy saving- applied to - VBN

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Chapter 2 Linear analysis of the Shark switched Reluctance Motor
l
l =
shk
t
(2.15)
2 ⋅ cos β
and δ l is the length of the air gap which is not effectively crossed by the field lines:
δ l = g ⋅ tan β
(2.16)
Fig.2.11 Geometry of the Shark teeth having different lengths
From equations (2.14), (2.15), (2.16) the equivalent length of the stack used in the conversion is
given by:
l
lshk
= − g ⋅ tan β
2 ⋅ cos β
e (2.17)
Under these considerations, the total active length ( total
l e ) for a Shark SRM with the stack length,
l stk is given by:
l
total
e
= 2 ⋅ n
⋅ l
lstk
l
= − 2 ⋅
cos β l
t
e
stk
shk
l
= 2 ⋅
l
le1
stk
shk
le
⋅
⋅ g ⋅ tan β
l1
lshk1
l
g g/cos
lshk
lshk
− g ⋅ tan β
2 ⋅ cos β
(2.18)
Equation (2.18) suggests that the effective conversion area is dependent on the length of the Shark
segment. There is a limit to the number of Shark teeth which may be built in a given stack length,
for which the Shark air gap behaves similarly to the cylindrical air gap. This limit is obtained from