PIDGS – PID controller with gain scheduling

Block SymbolLicensing group: ADVANCED
PIC

Function Description
The functionality of the PIDGS block is completely equivalent to the PIDU block. The only difference is that the PIDGS block has a at most six sets of basic PID controller parameters and allow bumpless switching of these sets by the ip (parameter set index) or vp inputs. In the latter case it is necessary to set GSCF = on and provide an array of threshold values thsha. The following rules define the active parameter set: the set 0 is active for vp < thrsha(0), the set 1 for thrsha(1) < vp < thrsha(2) etc. till the set 5 for thrsha(5) < vp. The index of the active parameter set is available at the kp output.

Inputs

dv

Feedforward control variable

Double (F64)

sp

Setpoint variable

Double (F64)

pv

Process variable

Double (F64)

tv

Tracking variable

Double (F64)

hv

Manual value

Double (F64)

MAN

Manual or automatic mode

Bool

off ..

Automatic mode

on ...

Manual mode

IH

Integrator hold

Bool

off ..

Integration enabled

on ...

Integration disabled

ip

Parameter set index   0  5

Long (I32)

vp

Switching analog signal

Double (F64)

Outputs

mv

Manipulated variable (controller output)

Double (F64)

dmv

Controller velocity output (difference)

Double (F64)

de

Deviation error

Double (F64)

SAT

Saturation flag

Bool

off ..

The controller implements a linear control law

on ...

The controller output is saturated

kp

Active parameter set index

Long (I32)

Parameters

hilim

Upper limit of the controller output  1.0

Double (F64)

lolim

Lower limit of the controller output  -1.0

Double (F64)

dz

Dead zone

Double (F64)

icotype

Controller output type  1

Long (I32)

1 ....

Analog output

2 ....

Pulse width modulation (PWM)

3 ....

Step controller unit with position feedback (SCU)

4 ....

Step controller unit without position feedback (SCUV)

npars

Number of controller parameter sets  6

Long (I32)

GSCF

Switch parameters by analog signal vp

Bool

off ..

Index-based switching

on ...

Analog signal based switching

hys

Hysteresis for controller parameters switching

Double (F64)

irtypea

Vector of controller types (control laws)  [6 6 6 6 6 6]

Byte (U8)

1 ....

D

2 ....

I

3 ....

ID

4 ....

P

5 ....

PD

6 ....

PI

7 ....

PID

RACTA

Vector of reverse action flags  [0 0 0 0 0 0]

Bool

0 ....

Higher mv higher pv

1 ....

Higher mv lower pv

ka

Vector of controller gains K  [1.0 1.0 1.0 1.0 1.0 1.0]

Double (F64)

tia

Vector of integral time constants Ti  [4.0 4.0 4.0 4.0 4.0 4.0]

Double (F64)

tda

Vector of derivative time constants Td  [1.0 1.0 1.0 1.0 1.0 1.0]

Double (F64)

nda

Vector of derivative filtering parameters N  [10.0 10.0 10.0 10.0 10.0 10.0]

Double (F64)

ba

Setpoint weighting factors – proportional part  [1.0 1.0 1.0 1.0 1.0 1.0]

Double (F64)

ca

Setpoint weighting factors – derivative part  [0.0 0.0 0.0 0.0 0.0 0.0]

Double (F64)

tta

Vector of tracking time constants  [1.0 1.0 1.0 1.0 1.0 1.0]

Double (F64)

thrsha

Vector of thresholds for switching the parameters  [0.1 0.2 0.3 0.4 0.5 0]

Double (F64)

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