Hi, we are working on a LED lamp and we need a PID to limit the temperature. The LEDs are PWM controlled by a microprocessor and the temperature is read with a thermistor.
Before to start with the PID design I would like to clarify some doubts.
1/ We do not have to reach a target temperature, but limiting the temperature to protect the user and electronics. We can do it by progressively dimming the LEDs intensity when it approach or pass the temperature limit, but we do not need the PID to increase the power to reach the temperature limit! So, how can we consider this in the PID design?
2/ The power of the lamp can be adjusted by the user and we plan to adjust the gains modelling the system with a 50% step input (at 100% the lamp may get too hot). Will the PID work well when the lamp is operated at different power values? Or do we need to consider it in the design somehow?
Beside the questions above we would really appreciate a guide or advice on the required steps.
Thank you very much.
Pedro (very beginner)
P.D.: I am refering to Robert's great article: https://www.allaboutcircuits.com/pr...trol-part-3-implementation-and-visualization/
Before to start with the PID design I would like to clarify some doubts.
1/ We do not have to reach a target temperature, but limiting the temperature to protect the user and electronics. We can do it by progressively dimming the LEDs intensity when it approach or pass the temperature limit, but we do not need the PID to increase the power to reach the temperature limit! So, how can we consider this in the PID design?
2/ The power of the lamp can be adjusted by the user and we plan to adjust the gains modelling the system with a 50% step input (at 100% the lamp may get too hot). Will the PID work well when the lamp is operated at different power values? Or do we need to consider it in the design somehow?
Beside the questions above we would really appreciate a guide or advice on the required steps.
Thank you very much.
Pedro (very beginner)
P.D.: I am refering to Robert's great article: https://www.allaboutcircuits.com/pr...trol-part-3-implementation-and-visualization/