How can I skip initial value on continuously updating closed loop system?

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Our model is a closed loop system and we need one parameter that gets updated in each run, but for the initial step the loop output is zero and the parameter that we are updating, has a division hence making it infinity. Is there any way we can skip this initial value or update our parameter as zero for first run, and from the next step let it be updated as it is?
As of now, we have tried using delay and switch blocks. Using conditional(if) block hasn’t been helpful although it is one of the best ways to eliminate infinity issues.
  3 Comments
shruthi
shruthi on 12 Mar 2014
Since we cannot share the original model, here is a sample. The K value gets updated at each iteration but if the initial value of Y is 0, the infinity problem arises. Please suggest ways in which this can be rectified.
Chintan
Chintan on 12 Mar 2014
So technically what we want is, if Y = 0, K =0, if Y is not equal to zero, let this division be performed just the way it is.

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Answers (2)

nl2605
nl2605 on 12 Mar 2014
You can specify the initial condition or value as 1 or whatever value you want for the integrator block. Just double click the integrator block and put in the value.
  2 Comments
Chintan
Chintan on 12 Mar 2014
Yes,
Also, there is one more condition here, if Y=0, K should also be zero. If I keep initial value of Y as 1, the X will still be subtracted in the summation, which is not right.
nl2605
nl2605 on 12 Mar 2014
If you have to skip all values coming from Y as '0' then you can check the condition using Relational Operator and set it to '1'. Check the Relational Operator block.

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nl2605
nl2605 on 12 Mar 2014
This should work. I hope so.

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