Change E-Stop so that it can also work with one string

- Also optimized CV charging

PLC/POUs/Utility/Controller/FB_PI.TcPOU

@@ -8,6 +8,7 @@ VAR_INPUT
 	rKp : REAL;
 	rTn : REAL;
 	
+	xEnable : BOOL;
 	xSaturated : BOOL := FALSE;
 END_VAR
 VAR_OUTPUT
@@ -19,6 +20,9 @@ VAR
 	_rIntegral : REAL := 0.0;
 	_rProportinal : REAL := 0.0;
 	
+	_rErrorSign : REAL;
+	_xHoldIntegrator : BOOL;
+	
 	_fbGetCurTaskIdx : GETCURTASKINDEX;
 	_rT : REAL;
 END_VAR
@@ -31,10 +35,18 @@ _rError := rSP - rPV;
 _rProportinal := rKp * _rError;
 
 // Calculate controller output
-rMV := _rProportinal + _rIntegral;
+IF xEnable THEN
+	rMV := _rProportinal + _rIntegral;
+ELSE
+	rMV := 0.0;
+END_IF
+
+_rErrorSign := _rError * rMV;
+
+_xHoldIntegrator := xSaturated AND (_rErrorSign > 0);
 
 // Stop integrator if saturated
-IF (NOT xSaturated) AND (rTn <> 0) THEN
+IF (NOT _xHoldIntegrator) AND (rTn <> 0) THEN
 	_rIntegral := _rIntegral + (rKp * _rT / rTn) * _rError;
 END_IF
 
@@ -56,7 +68,7 @@ END_VAR]]></Declaration>
       <Implementation>
         <ST><![CDATA[// Get current task time
 _fbGetCurTaskIdx();
-_rT := UDINT_TO_LREAL(TwinCAT_SystemInfoVarList._TASKInfo[_fbGetCurTaskIdx.index].CycleTime) * 10E-5;]]></ST>
+_rT := LREAL_TO_REAL(UDINT_TO_LREAL(TwinCAT_SystemInfoVarList._TASKInfo[_fbGetCurTaskIdx.index].CycleTime) * 10E-5);]]></ST>
       </Implementation>
     </Method>
     <Action Name="Reset" Id="{4227580c-e163-4250-9575-dd60ff3083af}">