Merge pull request #1249 from drf5n/PID_CI_v2

temperature.cpp: Add Conditional Integration to prevent excessive integral windup
This commit is contained in:
Bo Herrmannsen 2014-12-28 10:09:25 +01:00
commit 9c07d28bd6
2 changed files with 18 additions and 4 deletions

View file

@ -144,13 +144,13 @@
// Comment the following line to disable PID and enable bang-bang. // Comment the following line to disable PID and enable bang-bang.
#define PIDTEMP #define PIDTEMP
#define BANG_MAX 255 // limits current to nozzle while in bang-bang mode; 255=full current #define BANG_MAX 255 // limits current to nozzle while in bang-bang mode; 255=full current
#define PID_MAX 255 // limits current to nozzle while PID is active (see PID_FUNCTIONAL_RANGE below); 255=full current #define PID_MAX BANG_MAX // limits current to nozzle while PID is active (see PID_FUNCTIONAL_RANGE below); 255=full current
#ifdef PIDTEMP #ifdef PIDTEMP
//#define PID_DEBUG // Sends debug data to the serial port. //#define PID_DEBUG // Sends debug data to the serial port.
//#define PID_OPENLOOP 1 // Puts PID in open loop. M104/M140 sets the output power from 0 to PID_MAX //#define PID_OPENLOOP 1 // Puts PID in open loop. M104/M140 sets the output power from 0 to PID_MAX
#define PID_FUNCTIONAL_RANGE 10 // If the temperature difference between the target temperature and the actual temperature #define PID_FUNCTIONAL_RANGE 10 // If the temperature difference between the target temperature and the actual temperature
// is more then PID_FUNCTIONAL_RANGE then the PID will be shut off and the heater will be set to min/max. // is more then PID_FUNCTIONAL_RANGE then the PID will be shut off and the heater will be set to min/max.
#define PID_INTEGRAL_DRIVE_MAX 255 //limit for the integral term #define PID_INTEGRAL_DRIVE_MAX PID_MAX //limit for the integral term
#define K1 0.95 //smoothing factor within the PID #define K1 0.95 //smoothing factor within the PID
#define PID_dT ((OVERSAMPLENR * 10.0)/(F_CPU / 64.0 / 256.0)) //sampling period of the temperature routine #define PID_dT ((OVERSAMPLENR * 10.0)/(F_CPU / 64.0 / 256.0)) //sampling period of the temperature routine

View file

@ -455,7 +455,14 @@ void manage_heater()
//K1 defined in Configuration.h in the PID settings //K1 defined in Configuration.h in the PID settings
#define K2 (1.0-K1) #define K2 (1.0-K1)
dTerm[e] = (Kd * (pid_input - temp_dState[e]))*K2 + (K1 * dTerm[e]); dTerm[e] = (Kd * (pid_input - temp_dState[e]))*K2 + (K1 * dTerm[e]);
pid_output = constrain(pTerm[e] + iTerm[e] - dTerm[e], 0, PID_MAX); pid_output = pTerm[e] + iTerm[e] - dTerm[e];
if (pid_output > PID_MAX) {
if (pid_error[e] > 0 ) temp_iState[e] -= pid_error[e]; // conditional un-integration
pid_output=PID_MAX;
} else if (pid_output < 0){
if (pid_error[e] < 0 ) temp_iState[e] -= pid_error[e]; // conditional un-integration
pid_output=0;
}
} }
temp_dState[e] = pid_input; temp_dState[e] = pid_input;
#else #else
@ -558,7 +565,14 @@ void manage_heater()
dTerm_bed= (bedKd * (pid_input - temp_dState_bed))*K2 + (K1 * dTerm_bed); dTerm_bed= (bedKd * (pid_input - temp_dState_bed))*K2 + (K1 * dTerm_bed);
temp_dState_bed = pid_input; temp_dState_bed = pid_input;
pid_output = constrain(pTerm_bed + iTerm_bed - dTerm_bed, 0, MAX_BED_POWER); pid_output = pTerm_bed + iTerm_bed - dTerm_bed;
if (pid_output > MAX_BED_PID) {
if (pid_error_bed > 0 ) temp_iState_bed -= pid_error_bed; // conditional un-integration
pid_output=PID_MAX;
} else if (pid_output < 0){
if (pid_error_bed < 0 ) temp_iState_bed -= pid_error_bed; // conditional un-integration
pid_output=0;
}
#else #else
pid_output = constrain(target_temperature_bed, 0, MAX_BED_POWER); pid_output = constrain(target_temperature_bed, 0, MAX_BED_POWER);