ViPEC

[J. B. Wood]

Hello, all. Anyone using the freebie subject program and know of a source
for additional component models? It would be nice to have at least an
ideal transformer model. Thanks for your time and comment. Sincerely,

John Wood (Code 5550) e-mail: [email protected]
Naval Research Laboratory
4555 Overlook Avenue, SW
Washington, DC 20375-5337

 

[Chaos Master]

I found ancient runes from J. B. Wood[[email protected]] in the floor of
sci.electronics.cad:

John,

Hello, all. Anyone using the freebie subject program and know of a source
for additional component models? It would be nice to have at least an
ideal transformer model. Thanks for your time and comment. Sincerely,

Can it run SPICE models? If yes, you can create a .subckt with 2 inductors and a
a K command (that defines mutual inductance), as in:

(SPICE statements. Modify appropiately for .subckt)

L1 1 0 100u
L2 2 0 200u
K1 L1 L2 0.9999
^^^^^^ This is the coupling factor.

 

[J. B. Wood]

Can it run SPICE models? If yes, you can create a .subckt with 2 inductors and a
a K command (that defines mutual inductance), as in:

(SPICE statements. Modify appropiately for .subckt)

L1 1 0 100u
L2 2 0 200u
K1 L1 L2 0.9999
^^^^^^ This is the coupling factor.

Hello. ViPEC has a component model for two mutually-coupled inductors so
you can approximate an ideal transformer that way. To obtain transformer
action you not only have to make the coupling coefficient (K) as close to
unity as possible as you show above but the inductive reactance of L1 and
L2 at the operating frequency(s) must be very large. Sincerely, and
thanks for responding,

John Wood (Code 5550) e-mail: [email protected]
Naval Research Laboratory
4555 Overlook Avenue, SW
Washington, DC 20375-5337

 

[Mike Engelhardt]

Can it run SPICE models? If yes, you can create a .subckt with 2

Hello. ViPEC has a component model for two mutually-coupled inductors so
you can approximate an ideal transformer that way. To obtain transformer
action you not only have to make the coupling coefficient (K) as close to
unity as possible as you show above but the inductive reactance of L1 and
L2 at the operating frequency(s) must be very large. Sincerely, and
thanks for responding,

Usually SPICE allow the coupling coefficient to be exactly one,
so you can model a bit more ideal xformer. However, you might
be asking for a cross connected transconductance configuration
that will transform/reflect all the way down to DC. This would
be identical to the coefficient being 1 and the windings being
of infinite inductance but also of zero loss. Here's a generic
SPICE deck that shows the principle:

*
V1 1 0 PULSE(0 1 0 1u 1u .5m 1m)
R1 1 2 1K
X1 2 0 3 0 xform
R2 3 0 1K

* winding1: ports 1&2
* winding2: ports 3&4
..subckt xform 1 2 3 4
G1 0 N001 1 2 10
G2 0 N001 3 4 10
G3 2 1 N001 0 1
G4 4 3 N001 0 1
R1 N001 0 1G
..ends xform

..tran 3m 3m
..ends

--Mike