I don't use Excel. How do I convert the time in column A to minutes in Excel? I need the time to start at 0 and increment by minutes or fractions of minutes. The hours and AM are useless.
Michaeli, if you increase the rate of material going though the oven or furnace then the control output will net to be increased. A feed forward may be needed because the integrator time constant may be too slow to adapt in a reasonable amount of time.
cjd1964, the is a lot of videos on control theory on YouTube. The problem is that much of it is useless which is why people still tweak gains. I am in the process of making some videos "Peter Ponders PID". The first video I slam someone that is teaching about root locus.
https://youtu.be/uYhz3TuTkfM
It is a use technique that fills students minds up with useless ****. I show a better way but at the end I slam the control theory teachers because they provide the transfer functions when the big challenge is doing what we are doing here, identifying the system.
Here is a video about the basics of system identification. There are only two parameters to identify so I can show graphically what is happening with a 3D plot.
https://www.youtube.com/watch?v=qzr6eL90Aok
Here is an example of the basic technique used to tune a motor with a gain and time constant just like in the example. The only difference is that in the video I add an offset for a control output null because in real systems a control output of 0 doesn't always result in 0 speed.
Then I go back to the example in the root locus video and show how to do system identification when there are 4 parameter to identify. The teachers should show the students how to do this FIRST. Then the students will know where the transfer functions come from. I added a little reality with noise and truncation ( quantizing ) due to limited feed back resolution. Still the system identification works.
https://www.youtube.com/watch?v=lermULNDz3M
I can look at Michaeli's open loop response and tell right away it really should use a SOPDT ( second order plus dead time ) model so Michaeli's plant needs to have a plant gain, two time constants and a dead time identified. The control will need to be a PID.
The document Jamesau posted a link to only covers FOPDT systems. I have formulas for tuning SOPDT system but like I said in the video, they are useless unless one can first do the system identification which is what I will do as soon as I get the time converted to minutes starting at 0. The rest is easy.
I figured out how to adjust the time.