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smith predictor

Hey,

Ive been working on large time delay systems, so i have to design a smith predictor to eliminate the time delay factor. I tried to implement smith predctor but I am not sure if its correct or not. I am uploding the screenshort of the same, if any corrections are there pls let me know.

Thanking You.

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Most here (incl. me) don't have the simulation module installed, so I am not sure about the simulation part. I am not very familiar with simulation, so maybe I don't quite understand your code design.

 

However, what's the purpose of the second while loop? It does not do anything useful because the condition is met immediately and it will never iterate more than once. Also, since the 1 second wait on the outside occurs in parallel to the inner loop, it makes no difference. Once the inner parts have completed, it will have elapsed.

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Thank You for the reply sir.

The outer loop is required because  smith predictor has two loops. The output from the outer loop will be given to my system i.e. heater. Should I remove the outer loop or change the delay time in any of the loop? 

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I was not talking about the outermost loop.

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I have removed the outer loop and simplified the block diagram. Will this work ?? or need some more corrections? 

Thanking You

 

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@YD17 wrote:

I have removed the outer loop and simplified the block diagram. Will this work ?? or need some more corrections? 

 


 

To see if it will work, simply run it. Does it give the expected results?

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There is more to the Smith Predictor than what your diagram shows. Fortunately, we have an example of Smith Predictor shipping with the LabVIEW Control Design and Simulation Module:

 

C:\Program Files (x86)\National Instruments\LabVIEW 2015\examples\Control and Simulation\Case Studies\Process Control\Smith Predictor\Smith Predictor.vi

 

Smith.PNG

 

Also, please check this post here. This other student was able to get further a bit:

 

http://forums.ni.com/t5/LabVIEW/Control-amp-Simulation-Loop-Failed-to-Compile/m-p/3276094#M956773

 

 

Hopefully it helps!

Barp - Control, Simulation, RTT and HIL - National Instruments
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Thank You for the recommendation.

I have seen that example but it is in simulation and i need to implement on the actual system, so i am worried that will it work or not.

 

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