PID temperature controller

[BertenWal]

Hallo everybody, I am looking for a PID temperature controller program for Multisim. Please with the 741 op amp. I am also interested in amp circuits. Who can help me! Thanks Bert

[NatanBiesmans]

Hi Bert,

With a bit of searching I came across the following:

http://www.anale-ing.uem.ro/2009/2009_a9.pdf

It is a nice simple example of a PID controller.

When looking on Figure 1.b you will see the schematic.

This schematic has 5 different parts:

1. Voltage Follower:  This allows you to uncouple the rest of the circuit from the input, making sure you don't distort the input error signal. (Amplifier with gain 1)
   http://www.electronics-tutorials.ws/opamp/op-amp-building-blocks.html
2. Proportional: This is the P part of your PID controller. The P factor is the gain of this inverting amplifier.
   http://www.electronics-tutorials.ws/opamp/opamp_8.html
3. Integrator: This is the I part of your PID controller. The I factor is dependent on both the capacitance and resistance.
   http://www.electronics-tutorials.ws/opamp/opamp_6.html
4. Differentiation: This is the D part of your PID controller. The P factor is also dependent on both the capacitance and resistance.
   http://www.electronics-tutorials.ws/opamp/opamp_7.html
5. Addition: This will merge all the correcting signals from the P, I and D component with a certain gain.
   http://www.electronics-tutorials.ws/opamp/opamp_4.html

Please keep in mind that the input is the error signal. To get this signal you need to subtract the desired value from the actual value.

Have a look at the following:

http://www.electronics-tutorials.ws/opamp/opamp_5.html

Lastly I made the following example:

https://www.multisim.com/content/bFq4rZYn2YGh9Yggo2McnA/pid-control/

(You may want to switch around the reference and input temperature depending if you have a positive or negative feedback)

This should be enough to allow you to create your PID controller 🙂

Kind regards,

Natan Biesmans

[BertenWal]

Thank you Natan. This is a great example.