EVL6563S-200ZRC STMicroelectronics, EVL6563S-200ZRC Datasheet - Page 34

• 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
Figure 28. Model of coupled inductors with a = k n
Other possible choices of a are a = M/L
related (logically, not physically) to the leakage flux on the secondary side (see
and a = L
the primary side (see
From inspection of
inductance of the secondary winding measured with a shorted primary winding and that L
(1-k
Figure 29. Model of coupled inductors with a = n
The usefulness of having different models available, dependent on the value attributed to a,
is that it is possible to choose the one that best fits the specific problem under consideration,
leading to a simpler solution or minimum mathematical manipulations.
An important assumption underlying the modeling techniques so far described, is that the
behavior of the magnetic circuit, represented by an equivalent linear electric circuit, is also
linear; that is, the magnetic flux is proportional to the magneto-motive forces that excite the
windings. This is true only if the flux density inside the core is well below the saturation limit
of the material.
The models can give useful information also on what happens in case the magnetic core
saturates. With reference to the “physical model” of
and L
and their value can be considered constant; the non linear element of the circuit is L
2
) is the inductance of the primary winding with the secondary shorted out.
l2
are relevant to magnetic flux that is located mostly in air and so they do not saturate
2
/M = n
e
/k, which nulls L
Figure 28
Figure 29
and
Doc ID 17273 Rev 1
).
29
b
and puts all the elements related to the leakage flux on
it is apparent that the quantity L
1
= k n
e
, which nulls L
Figure 25
e
/k (a = n
e
(a = k n
a
, the leakage inductances L
and puts all the elements
e
/k model)
e
model)
2
(1-k
2
) is the
Figure 28
M
AN3180
, which
)
l1
1