Simulation of a PID regulation

The current temperature controllers most generally use a PID regulation method to track the set temperature. This means that the heating power HP applied is computed as a part proportional to the temperature error, another part proportional to the temperatur error integral and a third part proportional to its derivative. The corresponding constants are called P, I and D

HP = P * (T-Ts) + I * ∫ (T-Ts)*dt + D * d(T-Ts)/dt

where Ts is the requested temperature (the set value), and T is the actual system temperature.

This form lets you play with the P, I and D constants, and check the temperature match. Of coarse, the best match should go to the set temperature in minimal time, and exhibit only a limited overshoot. Adjust the P, I and D parameters, and click . You may also adjust the system thermal characteristics, the heater properties and the temperature profile. The computations are done on your computer. Please be patient, it might take a few seconds.

Profile parametersOffset 1 [K]
+100 +10 +1
-100 -10 -1
Offset 2 [K]
+100 +10 +1
-100 -10 -1
Offset 3 [K]
+100 +10 +1
-100 -10 -1
Regulation parametersP [W/K]
+10 +1 +0.1
-10 -1 -0.1
I [W/K/s]
+1 +0.1 +0.01
-1 -0.1 -0.01
D [W s/K]
+10 +1 +0.1
-10 -1 -0.1
System parametersThermal capacity C [J/K]
+10 +1 +0.1
-10 -1 -0.1
Thermal loss k [W/K]
+10 +1 +0.1
-10 -1 -0.1
Heating parametersMax. heating power [W]
+100 +10 +1
-100 -10 -1
Max. cooling power [W]
+100 +10 +1
-100 -10 -1
Bad settings

Today's temperature controllers have their own algorithm to tune the P, I and D constants to your system characteristics ("autotune"). So you'll probably never have to apply the tricks from this page. But please understand that if you let a controller trying to regulate the temperature as you just removed the sample and the sample holder, the autotune feature will make PID constants derive to some really weird values. And inserting back the sample could show you a big surprise !

All for this : PLEASE STOP THE TEMPERATURE CONTROL BEFORE REMOVING THE SAMPLE ! Thanks.


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Last modified 06/05/2010 D. Lovy