开云体育

Hello,

I am an electronics engineer and I work on wireless power supplies. For one of my simulations, I want to couple two inductors and I would like to simulate the design for various values of K.

Could someone please let me know why I can not use the following syntax as an LTSPICE directive?

K L1 L2 V(Var)

Where Var is a voltage source I have specified in the simulation circuit and it is a PWL (ramp function).

This syntax works for a variable resistor. I am wondering whether it is actually possible to apply the same logic to a coupling coefficient of the K statement.

Please help !!

Thank you.

Falcon

I have a feeling you should explicit the leakage inductances (i.e.
making them visible components in the schemo) and apply the statement to
them.

Le 17/07/2013 09:25, the_sky_falcon a écrit :

Hello,

I am an electronics engineer and I work on wireless power supplies.
For one of my simulations, I want to couple two inductors and I would
like to simulate the design for various values of K.

Could someone please let me know why I can not use the following
syntax as an LTSPICE directive?

K L1 L2 V(Var)

Where Var is a voltage source I have specified in the simulation
circuit and it is a PWL (ramp function).

This syntax works for a variable resistor. I am wondering whether it
is actually possible to apply the same logic to a coupling coefficient
of the K statement.

Please help !!

Thank you.

Falcon

[Non-text portions of this message have been removed]

Hi Jerry,
?
Thanks for the reply. The problem is, with wireless power supplies, the coupling between the primary and the secondary windings are very week. Therefore I can not get a figure for the leakage inductance.?( Ie: in a flyback transformer, I can short circuit the secondary and measure the primary inductance at 100kHz and use that figure for simulation with another uncoupled inductor put in series with my flyback primary inductor). However this method wont work for wireless power supplies as the coupling is very week. (If I short circuit my reciever coil and measure the inductance of the power transmitter track, the difference of inductance is miniscule.
?
Is there any other way of doing this? I can of course simulate for various values of k but I am very curious.
?
cheers,
?
Falcon

[Non-text portions of this message have been removed]

--- In LTspice@..., "the_sky_falcon" <the_sky_falcon@...> wrote:

Hello,

I am an electronics engineer and I work on wireless power supplies. For one of my simulations, I want to couple two inductors and I would like to simulate the design for various values of K.

Could someone please let me know why I can not use the following syntax as an LTSPICE directive?

K L1 L2 V(Var)

Where Var is a voltage source I have specified in the simulation circuit and it is a PWL (ramp function).

This syntax works for a variable resistor. I am wondering whether it is actually possible to apply the same logic to a coupling coefficient of the K statement.

Please help !!

Thank you.

Falcon

Falcon,

The correct syntax for assigning a variable to the coupling factor is:
K1 L1 L2 {Var}
.step param Var StartVal StopVal Inc ; substitute your own values

... same as it is for any other component value.

Regards,
Tony

Falcon, what you surely can do is to uses parameter for K that you can change for each simulation (or even make several runs for this parameter:

K12 L1 L2 {k12}

.param k12=0.9

I hope that this helps.

Stefan

Hi All,
?
Thanks so much for your help. I got it to work. I used :
?
K L1 L2 {X}
?
.step param {X} 0.01 0.07 0.01
?
Thanks again for your help.?
?
Falcon

Hello Falcon.
Maybe you have to verify my idea of building a mutual inductances. The coefficient K depends on the voltage.
I put my example in the TEMP folder.

Bordodynov.

17.07.2013, 11:44, "the_sky_falcon" <the_sky_falcon@...>:

In message <181191374056872@...>, dated Wed, 17 Jul 2013, =?koi8-r?B?4czFy9PBzsTSIOLP0sTPxNnOz9c=?= <BordodunovAlex@...> writes:

Maybe you have to verify my idea of building a mutual inductances. The coefficient K depends on the voltage. I put my example in the TEMP folder.

It doesn't run. There is confusion between Winding and Winding0
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

In message <1374056490.61943.YahooMailNeo@...>,
dated Wed, 17 Jul 2013, Dhara Weerasinghe <the_sky_falcon@...>
writes:

?
Thanks so much for your help. I got it to work. I used :
?
K L1 L2 {X}
?
.step param {X} 0.01 0.07 0.01
?
Thanks again for your help.?
?

It works in this case, but don't use X or x for an independent variable,
because it has a special meaning in some contexts. {K} or {KA} work.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

John Woodgate. Thank you very much for your comment. I have overwritten the file.
Bordodynov.

17.07.2013, 14:49, "John Woodgate" <jmw@...>:

In message <926671374058699@...>, dated Wed, 17 Jul 2013, =?koi8-r?B?4czFy9PBzsTSIOLP0sTPxNnOz9c=?= <BordodunovAlex@...> writes:

John Woodgate. Thank you very much for your comment. I have overwritten the file. Bordodynov.

I still can't find Winding0.sub
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

John Woodgate.
The model is in the file CORE.LIB. The symbol contains the name of the library.

Model:
.Subckt Winding0 l1 l2 mmf_out2 mmf_out params: N=100 rs=1m Tau=50n
B1 l1 50 v=v(7)*N
r1 50 5 {rs}
v1 5 l2 dc 0
bH2 mmf_out 6 v=i(v1)*N
v2 6 mmf_out2 dc 0
BF 7 0 i=i(v2) tripdt=50n
L 7 0 1 Rpar={1/tau} Cpar=.1f
.ends Winding0
Bordodynov.

17.07.2013, 16:09, "John Woodgate" <jmw@...>:

In message <93141374063607@...>, dated Wed, 17 Jul 2013, =?koi8-r?B?4czFy9PBzsTSIOLP0sTPxNnOz9c=?= <BordodunovAlex@...> writes:

The model is in the file CORE.LIB. The symbol contains the name of the library.

Then it's very odd that my computer can't find it. Anyway, thanks for the explanation.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

Is there a way to check BEFORE using a name whether there is a collision with that same name used somewhere else?

For example, in octave you type

who name

or,

who n*

and every use will pop up for you

Is there a way to do that in LTspice?


--- BordodunovAlex@... wrote:

From: Александр Бордодынов <BordodunovAlex@...>
To: "LTspice@..." <ltspice@...>
Subject: Re: [LTspice] Changing the mutual inductance coefficient of K statements with time
Date: Wed, 17 Jul 2013 16:20:07 +0400

John Woodgate.
The model is in the file CORE.LIB. The symbol contains the name of the library.

Model:
.Subckt Winding0 l1 l2 mmf_out2 mmf_out params: N=100 rs=1m Tau=50n
B1 l1 50 v=v(7)*N
r1 50 5 {rs}
v1 5 l2 dc 0
bH2 mmf_out 6 v=i(v1)*N
v2 6 mmf_out2 dc 0
BF 7 0 i=i(v2) tripdt=50n
L 7 0 1 Rpar={1/tau} Cpar=.1f
.ends Winding0
Bordodynov.

17.07.2013, 16:09, "John Woodgate" <jmw@...>:

In message <926671374058699@...>, dated Wed, 17 Jul 2013,
=?koi8-r?B?4czFy9PBzsTSIOLP0sTPxNnOz9c=?= <BordodunovAlex@...>
writes:

John Woodgate. Thank you very much for your comment. I have overwritten
the file. Bordodynov.

I still can't find Winding0.sub
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

John,

I just went through this on our systems here, too.

Did a search for 'content' of files, in my case all were text files, looking for a specific phrase.
so I was looking inside *.txt for "paramagnetic" to appear anywhere.

On Win98 systems - NO PROBLEM, found every file containing the text.

On WinXP Pro - NEVER found the files!!! [using that obnoxious 'puppy' search tool]
[Note: the identical files are mirrored/synced on ALL machines]
To verify, I went to the known files, and yes, the words were in the files, but that !@#$#!@#$ WinXP search puppy NEVER found the files !!!

Again you see, why I use the Win98 systems?

Anyway a heads up, I was told on the WinXP group that searching always fails and to use a different search tool, 3rd party, Agent Ransack. {?]






--- jmw@... wrote:

From: John Woodgate <jmw@...>
To: LTspice@...
Subject: Re: [LTspice] Changing the mutual inductance coefficient of K statements with time
Date: Wed, 17 Jul 2013 15:24:25 +0100

In message <93141374063607@...>, dated Wed, 17 Jul 2013,
=?koi8-r?B?4czFy9PBzsTSIOLP0sTPxNnOz9c=?= <BordodunovAlex@...>
writes:

The model is in the file CORE.LIB. The symbol contains the name of the
library.

Then it's very odd that my computer can't find it. Anyway, thanks for
the explanation.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

On Win98 systems - NO PROBLEM, found every file containing the text.

On WinXP Pro - NEVER found the files!!! [using that obnoxious 'puppy' search tool]
[Note: the identical files are mirrored/synced on ALL machines] To verify, I went to
the known files, and yes, the words were in the files, but that !@#$#!@#$ WinXP
search puppy NEVER found the files !!!

Again you see, why I use the Win98 systems?

Anyway a heads up, I was told on the WinXP group that searching always fails and to
use a different search tool, 3rd party, Agent Ransack. {?]

I suspect that what you are seeing is the difference in security systems that exist from WinXP onwards where files in the 'program Files' and 'Program Files (x86)' directories are considered to not be data files, and if your installation has put the data files there (by implication from your statement about files being synched across systems) then they may well be ignored by tools looking for data files.

Feel free to use a system that has no basic security against virus infestation such as your Win98 machine if that is the way you want to work.

Come on. *.txt files laced throughout the Program File space?

No way. These files were ALL files in the working space, data, and information areas.


Plus, WinXP so badly 'improved' some other built-in programs, I had to substitute the old versions from Win98 for them to operate correctly. two examples: old Notepad and MSPaint

But a bit off topic here, so will stop.




--- alan.b.pearce@... wrote:

From: <alan.b.pearce@...>
To: <LTspice@...>
Subject: RE: [LTspice] Changing the mutual inductance coefficient of K statements with time
Date: Wed, 17 Jul 2013 15:04:50 +0000

On Win98 systems - NO PROBLEM, found every file containing the text.

On WinXP Pro - NEVER found the files!!! [using that obnoxious 'puppy' search tool]
[Note: the identical files are mirrored/synced on ALL machines] To verify, I went to
the known files, and yes, the words were in the files, but that !@#$#!@#$ WinXP
search puppy NEVER found the files !!!

Again you see, why I use the Win98 systems?

Anyway a heads up, I was told on the WinXP group that searching always fails and to
use a different search tool, 3rd party, Agent Ransack. {?]

I suspect that what you are seeing is the difference in security systems that exist from WinXP onwards where files in the 'program Files' and 'Program Files (x86)' directories are considered to not be data files, and if your installation has put the data files there (by implication from your statement about files being synched across systems) then they may well be ignored by tools looking for data files.

Feel free to use a system that has no basic security against virus infestation such as your Win98 machine if that is the way you want to work.

In message <20130717075502.CBBBA34B@...>, dated Wed, 17 Jul 2013, Macy <macy@...> writes:

Did a search for 'content' of files, in my case all were text files, looking for a specific phrase. so I was looking inside *.txt for "paramagnetic" to appear anywhere.

My problem is different. I can open Core.lib in a real text reader (not Notepad) and see SUBCKT Winding0 there, but even with .inc core.lib added to the schematic as a Spice directive, I still get the error message 'Unknown subckt called in xu1 in n004....'

All files are saved to Desktop.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

--- In LTspice@..., John Woodgate <jmw@...> wrote:

In message <1374056490.61943.YahooMailNeo@...>,
dated Wed, 17 Jul 2013, Dhara Weerasinghe <the_sky_falcon@...>
writes:

?
Thanks so much for your help. I got it to work. I used :
?
K L1 L2 {X}
?
.step param {X} 0.01 0.07 0.01
?
Thanks again for your help.?
?

It works in this case, but don't use X or x for an independent variable,
because it has a special meaning in some contexts. {K} or {KA} work.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

John,

There is no reason you can't use x as a parameter. The only thing special about x is that it is used to represent the current in a nonlinear inductor and the volt across a nonlinear capacitance, but it is not visible outside the component model.

Rick

In message <ks6lf3+t8c1@...>, dated Wed, 17 Jul 2013, sawreyrw <sawreyrw@...> writes:

There is no reason you can't use x as a parameter. The only thing special about x is that it is used to represent the current in a nonlinear inductor and the volt across a nonlinear capacitance, but it is not visible outside the component model.

I just recommend not using it in order to avoid what would appear to be inexplicable error, especially where the context is, indeed, non-linear inductors.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK