This FB provides for a torque feedforward control for a drive system with a constant inertia. The feedforward control torque is limited with the inputs

		L_CT1P_TorquePreControl
AXIS_REF	-	Axis	xBusy	-	BOOL
BOOL	-	xEnable	xError	-	BOOL
L_MC1P_PreControlMode	-	ePreControlMode	eErrorID	-	L_IE1P_Error
LREAL	-	lrInertia	lrSetTorqueOut	-	LREAL
LREAL	-	lrViscousFriction
LREAL	-	lrCoulombFriction
LREAL	-	lrConstantTorque
LREAL	-	lrTorqueOverride
LREAL	-	lrTorqueLimitFactor
LREAL	-	lrTorqueRateLimit

Inputs

Name Data type	Information/possible settings
Axis AXIS_REF	Transfer of the axis data structure Motion axes (AXIS_REF)
xEnable BOOL	FALSE ä TRUE	Activation of the feedforward control
ePreControlMode L_MC1P_PrecontrolMode	Mode for calculating feedforward control AdditiveOffsetTorque In addition to the lrSetTorqueOut feedforward control torque, another torque is transmitted to the drive. This torque results from the acceleration, he parameterised moment of inertia of the motor and the load (parameter to subindex 37 and subindex 38 ). ExclusiveOffsetTorque Only the lrSetTorqueOut feedforward control torque calculated in the FB is transmitted to the drive.
lrInertia LREAL	Mass inertia of the complete system with regard to the gearbox output in [kgcm ² ]
lrViscousFriction LREAL	Proportion of the viscous friction with regard to the gearbox output in [Nm/(rad/s)]
lrCoulombFriction LREAL	Proportion of the Coulomb friction with regard to the gearbox output in [Nm]
lrConstantTorque LREAL	Constant torque with regard to the gearbox output in [Nm] A constant torque can be a hanging load.
lrTorqueOverride LREAL	Scaling factor for the calculated torque. 0: 0 % of the calculated torque is written to the axis 1: 100 % of the calculated torque is written to the axis. Internal maximum limitation: 200 % Description of the lrTorqueOverride input
lrTorqueLimitFactor LREAL	The calculated feedforward control torque is symmetrically limited to a percentage value of the rated torque of the axis. 0: No torque is transmitted to the axis. 1: Maximally 100 % of the rated torque of the axis is feedforward-controlled. Description of the lrTorqueLimitFactor input
lrTorqueRateLimit LREAL	Maximum change rate of the feedforward control torque with regard to the gearbox output in [Nm/s] Description of the lrTorqueRateLimit input

Name

Data type

Information/possible settings

Axis

AXIS_REF

Transfer of the axis data structure

Motion axes (AXIS_REF)

xEnable

BOOL

FALSE ä TRUE

Activation of the feedforward control

ePreControlMode

L_MC1P_PrecontrolMode

Mode for calculating feedforward control

AdditiveOffsetTorque

In addition to the lrSetTorqueOut feedforward control torque, another torque is transmitted to the drive. This torque results from

the acceleration,

he parameterised moment of inertia of the motor and

the load (parameter to subindex 37 and subindex 38 ).

ExclusiveOffsetTorque

Only the lrSetTorqueOut feedforward control torque calculated in the FB is transmitted to the drive.

lrInertia

LREAL

Mass inertia of the complete system with regard to the gearbox output in [kgcm ² ]

lrViscousFriction

LREAL

Proportion of the viscous friction with regard to the gearbox output in [Nm/(rad/s)]

lrCoulombFriction

LREAL

Proportion of the Coulomb friction with regard to the gearbox output in [Nm]

lrConstantTorque

LREAL

Constant torque with regard to the gearbox output in [Nm]

A constant torque can be a hanging load.

lrTorqueOverride

LREAL

Scaling factor for the calculated torque.

0: 0 % of the calculated torque is written to the axis

1: 100 % of the calculated torque is written to the axis.

Internal maximum limitation: 200 %

Description of the lrTorqueOverride input

lrTorqueLimitFactor

LREAL

The calculated feedforward control torque is symmetrically limited to a percentage value of the rated torque of the axis.

0: No torque is transmitted to the axis.

1: Maximally 100 % of the rated torque of the axis is feedforward-controlled.

Description of the lrTorqueLimitFactor input

lrTorqueRateLimit

LREAL

Maximum change rate of the feedforward control torque with regard to the gearbox output in [Nm/s]

Description of the lrTorqueRateLimit input

Outputs

Name Data type	Value/meaning
xBusy BOOL	TRUE	Processing is running.
xError BOOL	TRUE	An error has occurred. For details see eErrorID .
eErrorID L_IE1P_Error	If xError = TRUE: Error number for the error that has occurred.
lrSetTorqueOut LREAL	Feedforward control torque with regard to the gearbox output in [Nm] The calculation is made in the FB and without considering the inputs: lrTorqueOverride lrTorqueLimitFactor and lrTorqueRateLimit . Only suitable for diagnostics purposes, e.g. during the commissioning phase. No application-related interconnection required.

Name

Data type

Value/meaning

xBusy

BOOL

TRUE

Processing is running.

xError

BOOL

TRUE

An error has occurred. For details see eErrorID .

eErrorID

L_IE1P_Error

If xError = TRUE: Error number for the error that has occurred.

lrSetTorqueOut

LREAL

Feedforward control torque with regard to the gearbox output in [Nm]

The calculation is made in the FB and without considering the inputs:

lrTorqueOverride

lrTorqueLimitFactor and

lrTorqueRateLimit .

Only suitable for diagnostics purposes, e.g. during the commissioning phase.

No application-related interconnection required.

L_CT1P_TorquePreControl

Tip!

Inputs

Outputs