Using PIDs instead of thermostats
Posted: Mon Jan 18, 2021 12:11 am
Hello,
A while back, I built a heat-treating oven for use in knife-making. It used a PID controller.
A PID controller is a "Proportional, Integral, and Derivative" controller. Basically, instead of on/off, it allows for (layman's terms) ramping of temps.
In my current unautomated setup, using Inkbird controllers, when the humidity hits a certain low-point, it triggers the dehumidify option. This stays on until the controller hits the "off" level (which is actually the sum of two numbers, the humidity setting, and the allowed differential).
The problem is that because this is dependent upon air flow, it will always overshoot the target. So, I have to reverse engineer and lower the settings until the "overshoot" is accounted for. The problem is that I cannot hold a really tight tolerance on humidity.
A PID controller learns how to ramp things up, and when to turn it off, so that the "afterflow" is accounted for, and it will not exceed the upper limit.
I share this because I hope that we can find a way to incorporate PID controllers into the Home Assistant automation project.
A while back, I built a heat-treating oven for use in knife-making. It used a PID controller.
A PID controller is a "Proportional, Integral, and Derivative" controller. Basically, instead of on/off, it allows for (layman's terms) ramping of temps.
In my current unautomated setup, using Inkbird controllers, when the humidity hits a certain low-point, it triggers the dehumidify option. This stays on until the controller hits the "off" level (which is actually the sum of two numbers, the humidity setting, and the allowed differential).
The problem is that because this is dependent upon air flow, it will always overshoot the target. So, I have to reverse engineer and lower the settings until the "overshoot" is accounted for. The problem is that I cannot hold a really tight tolerance on humidity.
A PID controller learns how to ramp things up, and when to turn it off, so that the "afterflow" is accounted for, and it will not exceed the upper limit.
I share this because I hope that we can find a way to incorporate PID controllers into the Home Assistant automation project.