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Voltage feedback loop

  1. Dec 10, 2014 #1
    Hi

    Can anbody tell me where to put a PID controller in the picture below to design a voltage feedbaxk loop?

    Thanks
     

    Attached Files:

  2. jcsd
  3. Dec 10, 2014 #2

    jim hardy

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    Between line VC and the pulse generator.
    Difference between measured and desired VC is error , function PID(error) controls pulse width.
     
  4. Dec 10, 2014 #3
    Thanks jim.

    Would the picture below be correct
     

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  5. Dec 10, 2014 #4

    jim hardy

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    I'd connect top of PID to left side of pulse generator, to represent controlling pulse generator's input, instead of where you have it which is its output .
    And i'd add arrowheads to PID so it's intuitive that bottom is PID input and top is output.
    Likewise add arrowheads to pulse generator.

    The point is you let PID control the pulse width to make correct average voltage over at VC.. That's the basis of feedback control - continually measure , compare, adjust.
     
  6. Dec 10, 2014 #5
    Hi Jim

    Would this be ok, sorry for bothering you
     

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  7. Dec 10, 2014 #6

    jim hardy

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    Your most recent addition looks right , but now you have two PID's.
    Erase that first one you drew and it could work.
     
  8. Dec 10, 2014 #7
    Yeah was just a rough sketch.. Thanks alot
     
  9. Dec 10, 2014 #8

    jim hardy

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    Good luck!
     
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