Diff: PID.cpp

Revision:

3:d8646d8c994f

Parent:

2:b9610a2d2ea0

Child:

4:e3c9cb64be44

--- a/PID.cpp	Tue Oct 25 13:04:58 2016 +0000
+++ b/PID.cpp	Tue Oct 25 14:19:13 2016 +0000
@@ -3,11 +3,11 @@
 PID::PID(float Kp_in, float Ki_in, float Kd_in,  float Sampletime_in){
     
     // Parameters
-    Outputlimit_bool = false;
+    Outputlimit_bool = true;
     Inputlimit_bool = false;
-    AntiWindUp_bool = false;
-    outputLimits_H = 0.0;
-    outputLimits_L = 0.0;
+    AntiWindUp_bool = true;
+    outputLimits_H = 7.4;
+    outputLimits_L = -7.4;
     inputLimits_H = 0.0;
     inputLimits_L = 0.0; 
     feedbackvalue = 0.0; 
@@ -16,6 +16,7 @@
     Kp = Kp_in;
     Ki = Ki_in;
     Kd = Kd_in;
+    Ka = 0.1;
     
     // Sampling time
     Ts = Sampletime_in; 
@@ -44,10 +45,10 @@
     inputLimits_L = setinputLimits_L;     
 }
 
-void PID::EnableAntiWindUp(float Ka_)
+void PID::EnableAntiWindUp(float Ka_in)
 {
     AntiWindUp_bool = true;
-    Ka = Ka_;
+    Ka = Ka_in;
 }
 
 void PID::Compute(float reference_in, float feedbackvalue_in){
@@ -81,11 +82,13 @@
     // Output satuation
     if(Outputlimit_bool && AntiWindUp_bool){
         if( output >= outputLimits_H){
-            output = output - (output - outputLimits_H)*Ka;
-            //output = outputLimits_H;
+            // output = output - (output - outputLimits_H)*Ka;
+            error_I -= Ka*(output - outputLimits_H); // Anti-windup
+            output = outputLimits_H;
         }else if( output <= outputLimits_L){
-            output = output - (output - outputLimits_L)*Ka;
-            //output = outputLimits_L;
+            // output = output - (output - outputLimits_L)*Ka;
+            error_I -= Ka*(output - outputLimits_L); // Anti-windup
+            output = outputLimits_L;
         }
     }else{
         // output = output;