need a help for PID temperature control system

I would like to simulate PID incubator temperature control using a digital bulb for heating, analog fan for cooling, and sensor LM35, how can I do the simulink of this ? I it to work like this,

Is this control system below right ? if yes how to do the simulink ? if wrong, what should I add?

Thank you

Answer 1

[Birdman]

The control system you draw is almost right except few things. The Sum symbol at the output is not right. You should erase it. The output of the process incubator is your system output which you are going to observe. I added a simulink model to the attachment. It is a basic control flow and I wanted you to have an idea about how you are going to implement a control system in Simulink. You will see that there are Reference Input(Step block), PID Controller block, Process Incubator(Transfer Fcn block) and Sensor LM35(Transfer Fcn block). You need to have your system's and sensor's transfer function model in s-domain and then you have to enter the coefficients inside the block in decreasing order. After these stages, you need to design your PID Controller and after that enter the the Kp, Ki and Kd coefficients inside the block, you will see their places when you double click on the block and open it. At last, you need to run tests whether your control system is working. Try to work on it and let me know the results.

[Alaa jumah]

Thank you so much I appreciate that a lot, I did not understand what do you mean by (i need to design my PID controller) do you mean finding the values of Kp,Ki,Pd only ?, another problem is I could not get the transfer function of the sensor. So that i can try the simulink you did.

[Birdman]

Yes, I mean finding the values of Kp Ki and Kd.

Well, you can take it as a unit gain but I suggest you to model it by I/O data for the sensor.