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Identification Algorithm?

  1. Apr 12, 2012 #1
    Hello everybody
    I started recently working on an engineering problem that requires as a first step, the identification of the system.
    I already have a model which is a set of differential and algerbraic equations. Unfortunatelly, the system is a parameter varying one, and the aime is to identify these parameters. Taking in consideration that i have input and output measurements, and about 20 parameter to identify.
    Does any one have an idea about an identification algorithm that can be used for such problem?

  2. jcsd
  3. Apr 13, 2012 #2
    It really doesn't make much sense to estimate the parameters of a time-varying system, unless you have the model for the time dependence of the parameters as well (periodicity, explicit functional form?) or you have some specific real-time application that I can't think off right now. Anyway, I'd really appriciate it if you'd share your models and tell us what you're trying to do
  4. Apr 13, 2012 #3
    Hi elibj123

    Thanks for taking time and responding to my thread.

    In fact, i do have the expressions of the parameters, but since the model has 8 parameters, each parameter's expression contains three parameters, so 8*3=24 paameter to be identified.

    The sensitivity of the model to the parameters varries from one parameter to an other.

    I tried some algorithms such as different versions of the least squares, Gradient algo, Newton-Raphson, but they don't work!

    Unfortunatelly, i can't share the model, because i don't have the right to, at least for the time beying.:frown:

    I will be verry glad if you can provide some advices.
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