SPICE modeling of Plasma load

[JT]

Hello,

I need some help.

I have been modeling the plasma load of my system using a crude RC
circuit in SPICE. I would now like to replace this RC circuit with a
set of differential equations which describe the vi-relationship of my
load. I know SPICE is capable of doing this and it must be simple, but
I can't find any resources specific to implementation.

I'm working with Orcad PSPICE 9.1 and the DE forms are like:

dx/dt = C1*v(t)^3/2 / x^2 - C2
i(t) = C3*(dx/dt+C2)

Any form of direction will be greatly appreciated.

Thank you.

 

[Jim Thompson]

Refer to...

Newsgroups: alt.binaries.schematics.electronic
Subject: Re: SPICE modeling of Plasma load (S.E.D) -
PSpiceNumericExpressionConventions.pdf
Message-ID: <[email protected]>

Hello,

I need some help.

I have been modeling the plasma load of my system using a crude RC
circuit in SPICE. I would now like to replace this RC circuit with a
set of differential equations which describe the vi-relationship of my
load. I know SPICE is capable of doing this and it must be simple, but
I can't find any resources specific to implementation.

I'm working with Orcad PSPICE 9.1 and the DE forms are like:

dx/dt = C1*v(t)^3/2 / x^2 - C2
i(t) = C3*(dx/dt+C2)

Any form of direction will be greatly appreciated.

Thank you.

...Jim Thompson

 

[Robert Baer]

Hello,

I need some help.

I have been modeling the plasma load of my system using a crude RC
circuit in SPICE. I would now like to replace this RC circuit with a
set of differential equations which describe the vi-relationship of my
load. I know SPICE is capable of doing this and it must be simple, but
I can't find any resources specific to implementation.

I'm working with Orcad PSPICE 9.1 and the DE forms are like:

dx/dt = C1*v(t)^3/2 / x^2 - C2
i(t) = C3*(dx/dt+C2)

Any form of direction will be greatly appreciated.

Thank you.

Virtually by definition, a plasma is unstable, has negative
resistance, and is non-linear.
Have fun.

 

[Fred Bartoli]

Virtually by definition,

^^^^^^^^^^^^^^^^^^^^^^^

What the hell does this mean?

 

[JT]

Wine and bad comments on physical concepts are not what I'm interested
in right now.

I'm simply asking about making a two port model with some differential
equations as the engine.

Am I not in the right group?

 

[Jim Thompson]

Wine and bad comments on physical concepts are not what I'm interested
in right now.

I'm simply asking about making a two port model with some differential
equations as the engine.

Am I not in the right group?

You probably had a response from someone I've plonked. Just ignore
them.

...Jim Thompson

 

[JT]

Thanks Jim, got your file. It will certainly help when syntaxing my
equations. Now just to implement it all. I think the whole thing has
to do with Analog Behavioral Modeling in PSPICE. I'll start looking
there.

 

[Kevin Aylward]

Hello,

I need some help.

I have been modeling the plasma load of my system using a crude RC
circuit in SPICE. I would now like to replace this RC circuit with a
set of differential equations which describe the vi-relationship of my
load. I know SPICE is capable of doing this and it must be simple,
but I can't find any resources specific to implementation.

I'm working with Orcad PSPICE 9.1 and the DE forms are like:

dx/dt = C1*v(t)^3/2 / x^2 - C2
i(t) = C3*(dx/dt+C2)

Any form of direction will be greatly appreciated.

I have a similar model and example circuit for a CCFL in SuperSpice. You
could modify that one. You'll have to download the demo though

Kevin Aylward
[email protected]
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

 

[Robert Baer]

^^^^^^^^^^^^^^^^^^^^^^^

What the hell does this mean?

How about "by definition" then?