FT_PIWL

PI Controller with Anti-Windup

version 1.3 11. mar. 2009 programmer hugo tested by oscat

FT_PIWL is a PI controller. The PID controller works according to the fomula Y = IN *(KP+ KI * INTEG(e) ). a rst will reset the integrator to 0 lim_h and Lim_l set the possible output range of the controller. the output flag lim will signal that the output limits are active. the integrator ist equipped with anti wind-up circuitry which limits trhe total output ranke to lim_l and lim_h

default values for KP = 1, KI = 1, ILIM_L = -1E37, iLIM_H = +1E38.

Interface

Event Inputs

Name	Comment	With
INIT	Init Request
REQ	Normal Execution Request	IN, KP, KI, LIM_L, LIM_H
RST	Reset Integrator	IN

Event Outputs

Name	Comment	With
INITO	Init Confirmation	Y, LIM
CNF	Execution Confirmation	Y, LIM

Input Vars

Name	Type	Initial Value	Comment
IN	REAL		Process Variable / Error Input
KP	REAL	1.0	Proportional Gain
KI	REAL	1.0	Integral Gain
LIM_L	REAL	-1.0E38	Lower Limit
LIM_H	REAL	1.0E38	Upper Limit

Output Vars

Name	Type	Comment
Y	REAL	Controller Output
LIM	BOOL	Limit Reached Flag