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--- pid_implementation [2016/05/18 13:55] – [Output Derivative] coolstage
+++ pid_implementation [2018/05/22 10:33] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+====== PID Implementation ======
+The PID controller use proportional, integral, derivative and output derivative gain with fixed point arithmetic.
+----
+===== Proportional =====
+<code>
+Proportional = Proportional_gain * (Consigne - Reference)
+</code>
+----
+===== Integral =====
+<code>
+if Integral_gain == 0
+    Integral = 0
+else
+    Integral = Integral_gain * (Consigne - Reference) + Previous_integral_gain_sum
+We saturate the integral term with uIAntiWU_Limit
+if Integral > uIAntiWU_Limit
+    Integral = uIAntiWU_Limit
+if Integral < -uIAntiWU_Limit
+    Integral = -uIAntiWU_Limit
+</code>
+----
+===== Derivative =====
+<code>
+Derivative = Derivative_gain * (Error - Previous_error) with Error = (Consigne - Reference)
+</code>
+----
+===== Output Derivative =====
+<code>
+Output_Derivative = Output_derivative_gain * (PID_Output - Previous_PID_output)
+</code>
+----
+===== PID Output =====
+<code>
+(Proportional + Integral + Derivative + Output_Derivative) / Fixed_point_divider
+</code>
+----