EVL6563S-200ZRC STMicroelectronics, EVL6563S-200ZRC Datasheet - Page 32

• Manufacturer Part Number: EVL6563S-200ZRC
• Description: Power Management Modules & Development Tools Tranisition Mode PFC L6563S EVL Board
• Manufacturer: STMicroelectronics
• Type: Motor / Motion Controllers & Driversr

Specifications of EVL6563S-200ZRC

• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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Electrical equivalent circuit models of coupled inductors and transformers
inductance L
secondary winding and not completely linked to itself nor to the primary winding: it is called
secondary leakage inductance and is designated by L
This choice of a is perhaps the most logical one, and is also very useful because it provides
a clear physical meaning to each element of the equivalent circuit, shown in
is not the only one that makes sense.
Figure 25. Model of coupled inductors with a = n (a=n model)
Another possible choice, which leads to always positive values for L
This quantity, usually indicated with n
and numerically different from the physical turn ratio n :
Equation 27
which coincides with n if and only if L
coupling (k
This choice is particularly useful when the physical turn ratio n is unknown, so that it is
possible to complete the model computing n
In this case,
Equation 28
It is worth noting that L
third
secondary leakage inductances L
an average coupling between the windings and that the coupling k
to the secondary one is generally different from the coupling k
the primary one, and so L
geometry symmetrical in such a way that the reluctance of the leakage flux path is the same
for both windings, resulting in symmetrical coupling between windings (k
Equation 28
1
= k
Equation 26
b
is associated to the secondary leakage flux, the flux generated by the
2
. Note that this property is often erroneously attributed to the primary and
= k).
b
, reflected back to the primary side, equals L
, considering
l2
≠ n 2 L
Doc ID 17273 Rev 1
n
l1
l1
e
⎧
⎪
⎨
⎪
⎩
L
L
L
. It is L
and L
=
b
a
μ
l2
e
, is termed “equivalent turn ratio” and is conceptually
Equation 23
=
=
=
= n
L
L
k
(
(
2
l2
1
1
1
l2
2
L
−
. It is worth stating once more that k represents
−
1
=
L
e
= n 2 L
k
k
l1
from L
)
)
, that is in case of symmetrical magnetic
L
L
L
1
2
l
L
2
l
=
, takes the form:
1
l1
+
+
n
1
only in the special case of a winding
n
e
2
L
l2
and L
2
L
L
M
.
a
M
2
, which are easily measurable.
2
of the secondary winding to
1
a
of the primary winding
a
and L
, as pointed out by the
1
= k
b
, is a =
Figure 25
2
= k).
AN3180
L
, but it
2
⁄
L
1
.