STEP PID

2020-05-11T08:06:56.196000Z

This is my personal solution.. it works!!:
FUNCTION_BLOCK fb_ctrl_step
VAR_INPUT
// parametri PID
actualValue : REAL;
setPoint : REAL;
kP : REAL;
kI : REAL;
// gestione uscite UP DOWN
limitSwitchUp : BOOL;
limitSwitchDn : BOOL;
minPulseUpDuration : TIME;// durata minima dell'impulso di salita
maxPulseUpDuration : TIME;// durata massima dell'impulso di salita
minPulseDnDuration : TIME;// durata minima dell'impulso di discesa
maxPulseDnDuration : TIME;// durata massima dell'impulso di discesa
pausePulseUpDuration : TIME;// duarata pausa impulso di salita
pausePulseDnDuration : TIME;// durata pausa impulso di discesa
// gestione manuali
manualMode : BOOL;
manualUp: BOOL;
manualDn:BOOL;
END_VAR

VAR_OUTPUT
qUp:BOOL; // uscita per aumentare
qDn :BOOL; // uscita per diminuire
END_VAR
VAR
oscatPI: OSCAT_BASIC.CTRL_PI;
oscatHyst3: OSCAT_BASIC.HYST_3;

upCommandRising : R_TRIG;
dnCommandRising : R_TRIG;

oscatGenPulseUp:OSCAT_BASIC.GEN_PULSE;
oscatGenPulseDn:OSCAT_BASIC.GEN_PULSE;

END_VAR
oscatPI(
ACT:= actualValue,// valore di processo
SET:= setPoint, // setpoint
SUP:= 0 , // soppressione (0)
OFS:= 0, // offset da sommare (0)
M_I:= 0, // output se in manuale
MAN:= manualMode, // manuale
RST:= manualMode, // reset - il pid si resetta in manuale
KP:= kP, // costante proporzionale
KI:= kI, // costante integrale
LL:= -1*TIME_TO_REAL(maxPulseDnDuration), // limite inferiore è la durata massima dell'impulso di salita
LH:= TIME_TO_REAL(maxPulseUpDuration), // è la durata massima dell'impulso di discesa
//Y=>y ,// uscita del filtro
);

oscatHyst3(
in:= oscatPi.Y,
hyst:=0.1 ,
val1:= -1* TIME_TO_REAL(minPulseDnDuration) ,
val2:= TIME_TO_REAL(minPulseUpDuration) ,
//Q1=> comando di discesa ,
//Q2=> comando di salita
);

// discesa
oscatGenPulseDn.ENQ S= oscatHyst3.Q1 AND NOT oscatGenPulseUp.ENQ ;
oscatGenPulseDn.ENQ R= NOT oscatHyst3.Q1 AND oscatGenPulseDn.Q ;
oscatGenPulseDn( PTH:= REAL_TO_TIME (-oscatPI.y) ,
PTL := pausePulseDnDuration ,
//Q=>
);

// salita
oscatGenPulseUp.ENQ S= oscatHyst3.Q2 AND NOT oscatGenPulseDn.ENQ ;
oscatGenPulseUp.ENQ R= NOT oscatHyst3.Q2 AND oscatGenPulseUp.Q ;
oscatGenPulseUp( PTH:= REAL_TO_TIME (oscatPI.y) ,
PTL := pausePulseUpDuration ,
//Q=>
);

qUp := ((manualMode AND manualUp) OR (NOT ManualMode AND oscatGenPulseUp.Q ))AND NOT limitSwitchUp;
qDn := ((manualMode AND manualDn) OR (NOT ManualMode AND oscatGenPulseDn.Q ))AND NOT limitSwitchDn;

END_FUNCTION

STEP PID

2020-05-08T09:01:22.750000Z

thanks, I try with the ThreePointController, although I preferred to be able to interact with a control system with PI parameters, thanks a lot anyway

STEP PID

2020-05-08T08:56:45.151000Z

Hi, for control a temperature with one output that heats and one that cools, you can use Three-point controls.
ThreePointController: Function block for implementing a three-point control
ThreePointControllerWithValueHysteresis: Function block for implementing a three-point control with
value-based modulation
(Part of Control Loop Library)

STEP PID

2020-05-07T15:05:35.756000Z

'm sorry but there is a problem with the link that i have sent

the function that i have to replicate is this:

FB_CTRL_STEP_PID
fb_ctrl_step_pid
The function block controls a digitally manipulated variable for integrating actuators. It is based on a standard PID controller with an additional binary output signal along with the analog output and operates without a precise position feedback signal.

The position feedback signal required to calculate the controller output, is estimated with the help of the limiting values and the time required to reach those limits. The function block then creates pulses based necessary to drive the actuator such as a servo motor.

the step pid are typically used to control a temperature with one output that heats and one that cools, and this is what I have to do

STEP PID

2020-05-07T11:50:02.498000Z

the pid steps are typically used to control a temperature with one output that heats and one that cools, this is what this function does https://infosys.beckhoff.com/english.php?content=../content/1033/tf4100_tc3_controller_toolbox/9007199500176779.html&id and this is what I have to do

STEP PID

2020-05-07T11:17:14.818000Z

Hello,
I would give this a try:
https://store.codesys.com/control-loop-library.html?store=default&from_store=en

STEP PID

2020-05-07T10:32:55.172000Z

Hello, I have to create an application that needs a block like this ..
https://infosys.beckhoff.com/english.php?content=../content/1033/tf4100_tc3_controller_toolbox/9007199500176779.html&id
is there an equivalent in codesys or OSCAT libraries or do I have to build it?
thanks

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