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Add PID_FAN_SCALING option (#15585)

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haschtl
2019-11-26 10:34:43 +01:00
committed by Scott Lahteine
parent 8ccfdaca02
commit ff6518c0a8
112 changed files with 5377 additions and 22 deletions
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50
config/examples/delta/kossel_xl/Configuration_adv.h
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@@ -197,6 +197,56 @@
#define DEFAULT_Kc (100) //heating power=Kc*(e_speed)
#define LPQ_MAX_LEN 50
#endif
/**
* Add an experimental additional term to the heater power, proportional to the fan speed.
* A well-chosen Kf value should add just enough power to compensate for power-loss from the cooling fan.
* You can either just add a constant compensation with the DEFAULT_Kf value
* or follow the instruction below to get speed-dependent compensation.
*
* Constant compensation (use only with fanspeeds of 0% and 100%)
* ---------------------------------------------------------------------
* A good starting point for the Kf-value comes from the calculation:
* kf = (power_fan * eff_fan) / power_heater * 255
* where eff_fan is between 0.0 and 1.0, based on fan-efficiency and airflow to the nozzle / heater.
*
* Example:
* Heater: 40W, Fan: 0.1A * 24V = 2.4W, eff_fan = 0.8
* Kf = (2.4W * 0.8) / 40W * 255 = 12.24
*
* Fan-speed dependent compensation
* --------------------------------
* 1. To find a good Kf value, set the hotend temperature, wait for it to settle, and enable the fan (100%).
* Make sure PID_FAN_SCALING_LIN_FACTOR is 0 and PID_FAN_SCALING_ALTERNATIVE_DEFINITION is not enabled.
* If you see the temperature drop repeat the test, increasing the Kf value slowly, until the temperature
* drop goes away. If the temperature overshoots after enabling the fan, the Kf value is too big.
* 2. Note the Kf-value for fan-speed at 100%
* 3. Determine a good value for PID_FAN_SCALING_MIN_SPEED, which is around the speed, where the fan starts moving.
* 4. Repeat step 1. and 2. for this fan speed.
* 5. Enable PID_FAN_SCALING_ALTERNATIVE_DEFINITION and enter the two identified Kf-values in
* PID_FAN_SCALING_AT_FULL_SPEED and PID_FAN_SCALING_AT_MIN_SPEED. Enter the minimum speed in PID_FAN_SCALING_MIN_SPEED
*/
//#define PID_FAN_SCALING
#if ENABLED(PID_FAN_SCALING)
//#define PID_FAN_SCALING_ALTERNATIVE_DEFINITION
#if ENABLED(PID_FAN_SCALING_ALTERNATIVE_DEFINITION)
// The alternative definition is used for an easier configuration.
// Just figure out Kf at fullspeed (255) and PID_FAN_SCALING_MIN_SPEED.
// DEFAULT_Kf and PID_FAN_SCALING_LIN_FACTOR are calculated accordingly.
#define PID_FAN_SCALING_AT_FULL_SPEED 13.0 //=PID_FAN_SCALING_LIN_FACTOR*255+DEFAULT_Kf
#define PID_FAN_SCALING_AT_MIN_SPEED 6.0 //=PID_FAN_SCALING_LIN_FACTOR*PID_FAN_SCALING_MIN_SPEED+DEFAULT_Kf
#define PID_FAN_SCALING_MIN_SPEED 10.0 // Minimum fan speed at which to enable PID_FAN_SCALING
#define DEFAULT_Kf (255.0*PID_FAN_SCALING_AT_MIN_SPEED-PID_FAN_SCALING_AT_FULL_SPEED*PID_FAN_SCALING_MIN_SPEED)/(255.0-PID_FAN_SCALING_MIN_SPEED)
#define PID_FAN_SCALING_LIN_FACTOR (PID_FAN_SCALING_AT_FULL_SPEED-DEFAULT_Kf)/255.0
#else
#define PID_FAN_SCALING_LIN_FACTOR (0) // Power loss due to cooling = Kf * (fan_speed)
#define DEFAULT_Kf 10 // A constant value added to the PID-tuner
#define PID_FAN_SCALING_MIN_SPEED 10 // Minimum fan speed at which to enable PID_FAN_SCALING
#endif
#endif
#endif
/**