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Spark plug/Igniter/Spark gap in PSpice

  1. May 29, 2012 #1
    As far as I can tell, none of these come with the student edition of PSpice. The first problem is I can't find a model for any of these things. The second problem is I don't know how to import a custom part. Worst come to worst, I could make the part myself, but once again, I have no experience with this.

    Googling hasn't helped much, I can't really find good help for PSpice 9.2. I was hoping to find a library file I could just throw in with the rest of my libraries, but I haven't found any libraries floating around the internet. Is there some kind of PSpice parts database or something, where I could at least download the right part?

    It seems like you need to download a model file and then somehow import that. I watched a video on how to do it for LTspice and it seemed completely alien to anything I've done before.

    As I'm sure you can tell, I am not sure how to even start this. I don't even have a rough estimate for how long this will take. I thought of using a voltage switch + current switch to do a really rough simulation but I don't seem to have those parts either.

    I don't really need much more then that, actually. I just want the resistance to change when the break voltage is reached... That would probably be enough. Like I said though, I don't know how to approach this. I've been building everything in schematic mode so far so I don't know how the text stuff works at all.
  2. jcsd
  3. May 29, 2012 #2
    What behavior of the sparkplug are you trying to model?
  4. May 30, 2012 #3
    Basically trying to model a 20us voltage pulse over a transformer, and it's effects on the spark gap. Looking for possible short circuit failures and just trying to get a general feel for what's going on in that 30-40us after the pulse is applied.

    I was looking for any possible model to start, I've been using a resistor up until now but I don't think that's quite adequate to use as a reference point.
  5. May 30, 2012 #4
    Don't worry. I do a lot of PSpice and I'll help you.

    Actually, if you are lucky enough you'll get the PSpice part or library from the internet. But in most of the cases, you wont get anything.

    Next thing to do is to search for SPICE model which you can run by including in a circuit file. You can download datasheet or search internet for that.

    Even if, the above two steps fail there's a way. But in this case you have to know the current-voltage relationship and many other small/large signal parameters. Try to mathematically formulate equations/expressions that look closer to known model components (e.g. diode, resistor, capacitor etc). Then you can write a macromodel code which can be used as a model of spark plug.
  6. May 30, 2012 #5
    Hey, thanks for replying. I've begun trying to make the part myself following the tutorial included with PSpice. So far it's going well, and if I have any questions I'll post them here. However, something else unrelated has popped up, maybe you have some idea what's going on.

    I was doing a basic test circuit, just to see if my inductors were having problems during simulation (as I suspected they were.) The test circuit was incredibly basic so I'll just describe it here. A DC pulse source, attached to an inductor and resistor in series. When the inductor is facing the default direction, it works as expected, but when I flip it horizontally so that the ends are switched, the voltage over the resistor is simply the square wave. It's as if the inductor was not there at all. Any thoughts? If not I'll just try and restructure my circuit without flipping anything and see what happens then.
  7. May 30, 2012 #6
    Alright, I guess I wasn't following a tutorial on how to make .model files, just how to make custom part images for particular .model files. I've been looking at different parts in the .model editor and was wondering if there's somewhere I can look to find out how to use whatever this language is.
  8. May 31, 2012 #7
    Everything is specified in "Capture Reference Manual" and "PSpice Reference Manual". If you don't have them, search and download.
  9. May 31, 2012 #8
    That kinda thing should not happen. Check that when you flip, you are not shorting the two inductor terminals.
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