PID vs. MicroController

Discussion in 'General Electronics Chat' started by assuc, Jan 6, 2014.

  1. assuc

    Thread Starter Member

    Mar 23, 2012
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    Greetings,
    PID control is/was used as the efficient way to control the process of a plant(basic example temperature or motor speed control). Also the same can be done via Micro-controller based system so what is the basic difference one should opt to choose between the two.
    keeping aside Speed, Hardware Area and Cost
     
  2. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    PID is a process or function
    A microcontroller is a device that can perform PID..
    You don't choose between the 2.. You need one to perform the other..
     
  3. GetDeviceInfo

    Senior Member

    Jun 7, 2009
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    analog implementations of PID are typically dedicated to that function only, while a micro can do a bunch of other stuff as well as the PID function, making it the modern choice. I don't think that answered your question, but then your question wasn't well thought out.
     
  4. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Original PID was actually mechanical an pneumatic, not electric/electronic.
     
  5. MaxHeadRoom

    Expert

    Jul 18, 2013
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    And evidently developed in the process for a self steering mechanism on ships/boats.
    Done by studying the motions by the helmsman.
    Max.
     
  6. crutschow

    Expert

    Mar 14, 2008
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    One advantage of doing a PID loop using a micro is that the circuit response is not subject to the various resistor and capacitor component tolerances that an analog PID circuit has. It only depends upon the accuracy of the micro system clock. Another consideration is that a control loop can be done with a micro using Fuzzy Logic which can be easier to optimize for good control loop response as compared to a PID loop (which is using digital functions to simulate analog RC response)
     
  7. assuc

    Thread Starter Member

    Mar 23, 2012
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    Let's consider an example say if I want to control a temperature of a room such that it maintains 50degrees so as the temperature falls the incandescent bulb or heater turns ON and vice versa. Now what should one prefer PID or Microcontroller
     
  8. Brownout

    Well-Known Member

    Jan 10, 2012
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    That's a false choice. PID can be used with or without a microcontroller. A microcontroller can be used with or without PID. There is no logical way to answer your question.

    An example of a logical question would be something like: should PID be implemented with a microcontroller or with op-amps? There may not still be a definitive answer, but at least that question would make some sense.
     
  9. MaxHeadRoom

    Expert

    Jul 18, 2013
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    As already explained, comparison of PID and Micro is meaningless, unless you mean non PID by micro?
    But if you want an accurate control of any kind, a PID loop is really the only way.
    Any other method usually results in temperature swings around the set point.
    PID by definition does not mean 'other than' micro control.
    Max.
     
  10. assuc

    Thread Starter Member

    Mar 23, 2012
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    By the question i meant what choice to prefer for accurate result... As temperature swings occurs around the set point, to achieve it more quickly and evidently.
     
  11. assuc

    Thread Starter Member

    Mar 23, 2012
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    That is the point how accuracy is achieved when it has capacitance and resistances with their tolerance levels.
     
  12. shteii01

    AAC Fanatic!

    Feb 19, 2010
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    The choices are: PI, PD, PID.

    uC is a device you program it and it will do whichever control function you want. You want PI, program the uC to do PI. You want PD, program the uC to do PD. You want PID, program uC to do PID.
     
  13. tshuck

    Well-Known Member

    Oct 18, 2012
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    Are you even reading these responses?

    A microcontroller is not an alternative to a PID. Go look up PID, then look up microcontrollers and understand how one does not preclude the other.
     
  14. Austin Clark

    Member

    Dec 28, 2011
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    It's obviously a language barrier problem. Don't give the guy too much grief. If he took the time to make an account and post, he's going to take the time to read the responses.
     
  15. bertus

    Administrator

    Apr 5, 2008
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  16. tshuck

    Well-Known Member

    Oct 18, 2012
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    Language barrier or not, there seems to be some other factor at play if two people have flat out said that attempting to compare a PID and microcontroller is comparing two entirely different things.
     
  17. MrChips

    Moderator

    Oct 2, 2009
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    Perhaps the OP is confused with the terms PID and microcontroller.

    Possibility #1
    The OP knows that a PID refers to a "controller" and wants to compare that with a micro "controller".

    Possibility #2
    The OP assumes that all PID controllers are implemented with analog electronics where as a microcontroller uses digital techniques.

    To the OP, PID control is a mathematical algorithm for achieving smooth steady state output. PID control can be implemented with analog or digital techniques. Analog circuitry using opamps, etc., may achieve faster response times. However, fast digital processing can reach similar speeds as analog circuitry.
     
  18. assuc

    Thread Starter Member

    Mar 23, 2012
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    Well when was I looking for alternative, I am discussing the best way to achieve it may it be via op amps or by coding.
     
  19. assuc

    Thread Starter Member

    Mar 23, 2012
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    Thanks, as for my case its possibility # 2
     
  20. assuc

    Thread Starter Member

    Mar 23, 2012
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    Mods may close this thread
     
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