Here is my prototype for a fan control system based on Arduino. The idea is to maintain a constant temperature by controlling the speed of a fan by changing its supply voltage.
It is still a work in progress and I do not have a schematic yet, but the control algorithm itself seems to work very well already.
The test bench uses a paper box, a hot glue gun as a heat source and an old 8cm 12V PC fan.
It uses a PID (Proportional-Integral-Derivative) control algorithm to calculate the adequate power % to apply to the fan, through a PWM controlled MOSFET.
Once stabilized, the temperature is kept within a 0.1ºC error, and a stable fan speed.
The motivation was to design a system to maintain just the right temperature at the back of an absorption fridge in the summer by using just the right fan speed to avoid noise. It can be used in any forced ventilation application though.
Post time: Jul-28-2017