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Hi Tony,
I just need something for higher frequency, say 10MHz.

--- In LTspice@..., legg@... wrote:

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

--- In LTspice@..., legg@ wrote:

Here's an example of a material exhibiting reduced permeability with frequency.



RL

The link doesn't show anything about permeability vs. frequency.

Rick

Material permeability is directly related to inductance of the sample, if only the frequency changes in the test.

RL

RL,

I understand that, but there is no function of frequency shown at that link. If you don't think that is the case, double check it.

Rick

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

--- In LTspice@..., legg@ wrote:

Here's an example of a material exhibiting reduced permeability with frequency.



RL

The link doesn't show anything about permeability vs. frequency.

Rick

Material permeability is directly related to inductance of the sample, if only the frequency changes in the test.

RL

--- In LTspice@..., Dhara Weerasinghe <the_sky_falcon@...> wrote:

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

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

Falcon,

You got lucky. Even though you were given the right syntax, you chose not to use it.

The K statement should use the Kx syntax, where x is usually numeric, but must be unique. If there is only one K statement, it will obviously be unique, but as soon as you introduce another, you must explicitly make it so.

Secondly, the curly braces are not appropriate in the .step param statement. LTspice often silently ignores syntax errors, but that shouldn't be a guiding principle.

Perhaps you should read the manual. (Usual expletive omitted.)

Regards,
Tony

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

I have a simulation of a open loop SMPS that I would like to know the transformer losses, but using the following script gives an efficiency of >100%.....which I know is not true.

After digging a bit I came across a example in the files area for AC power, complex_power1_meas-1.asc. But the notes state "Steady State Power Calculation With Pure Sine Voltages And Linear Components".

My question is will this same approach work for a rectangle waveform?


.param mes_start=6m mes_end=9.9m

.meas TRAN Vrms_pri RMS V(vpri1,vpri2) from {mes_start} to {mes_end}
.meas TRAN Irms_pri RMS I(L1) from {mes_start} to {mes_end}
.meas Ppri PARAM Vrms_pri*Irms_pri

.meas TRAN Vrms_can RMS V(vac_can1,vac_can2) from {mes_start} to {mes_end}
.meas TRAN Irms_can RMS I(L2) from {mes_start} to {mes_end}
.meas Pcan PARAM Vrms_can*Irms_can

.meas TRAN Vrms_rs RMS V(vac_rs1,vac_rs2) from {mes_start} to {mes_end}
.meas TRAN Irms_rs RMS I(L3) from {mes_start} to {mes_end}
.meas Prs PARAM Vrms_rs*Irms_rs

.meas eff_tx PARAM (Pcan+Prs)/Ppri

Hello,

Discounting errors in the scripts, "measured" efficiencies of greater than 100%, are often due to not waiting long enough before deciding "steady state" has been reached. If there is significant ringing in the SMPS transient response and the measurement interval is over a period of net downward trajectory of the output voltage, it is easily possible that more energy is being taken out of the system than is being put in. You should do some sanity checks that prove that you are not in such a region.

First step: try doubling the simulation time.

Conversely, an upward trajectory in voltage could indicate a pessimistic estimation of efficiency.

Regards,
Tony

In message <ks6pg9+ovi6@...>, dated Wed, 17 Jul 2013, sawreyrw <sawreyrw@...> writes:

A K statement is not directly applicable to a nonlinear inductor.

But that is exactly what the thread is about!
--
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 <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

John,

I know the statement flux={x}*tanh(x) looks strange, but LTspice knows that the parameter x is not the current x. Of course, I wouldn't recommend it, because of the possible confusion others might have. A K statement is not directly applicable to a nonlinear inductor.

Rick

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

--- 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 <ks6d15+3s9u@...>, dated Wed, 17 Jul 2013, jean_claudeabeille <jean_claudeabeille@...> writes:

Can anybody here tell me where I can find a spice model for this PNP ? Thank you;

Apart from the packaging, it is similar to a BC556 or BC557.
--
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 <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

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.

Can anybody here tell me where I can find a spice model for this PNP ?
Thank you;

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.

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

I have a simulation of a open loop SMPS that I would like to know the transformer losses, but using the following script gives an efficiency of >100%.....which I know is not true.

After digging a bit I came across a example in the files area for AC power, complex_power1_meas-1.asc. But the notes state "Steady State Power Calculation With Pure Sine Voltages And Linear Components".

My question is will this same approach work for a rectangle waveform?


.param mes_start=6m mes_end=9.9m

.meas TRAN Vrms_pri RMS V(vpri1,vpri2) from {mes_start} to {mes_end}
.meas TRAN Irms_pri RMS I(L1) from {mes_start} to {mes_end}
.meas Ppri PARAM Vrms_pri*Irms_pri

.meas TRAN Vrms_can RMS V(vac_can1,vac_can2) from {mes_start} to {mes_end}
.meas TRAN Irms_can RMS I(L2) from {mes_start} to {mes_end}
.meas Pcan PARAM Vrms_can*Irms_can

.meas TRAN Vrms_rs RMS V(vac_rs1,vac_rs2) from {mes_start} to {mes_end}
.meas TRAN Irms_rs RMS I(L3) from {mes_start} to {mes_end}
.meas Prs PARAM Vrms_rs*Irms_rs

.meas eff_tx PARAM (Pcan+Prs)/Ppri

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

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

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