Drive Configuration
Initial Setup of the Register Tree
plied, a change of direction causes a position shift of the actual position. To smoothing this shift, a
second order low pass filter is applied. The dynamics of this filter can be configured with the param-
eter
BacklashDuration
. Typical values are in range of 0.1 to 0.5s.
A small value causes a fast shift of the position.
A big value causes a slow shift of the position.
Note
Note
Backlash Compensation is suitable to compensate contouring errors during slow motion. For
high dynamic moves the application of backlash compensation can be counterproductive as
the backlash error not only depends on the move direction but also on the acceleration and
deceleration.
5.2.6 Axis[].Parameters.PositionController.Controllers
The controller node contains registers to configure
Controller[0]
and
Controller[1]
. The structure of the
controller is described in section 5.4. For an axis with a single encoder only
Controller[0]
has to be con-
figured.
Controller[1]
is only used if an axis provides a second encoder signal e.g. for dual loop-control.
Kp
,
Ki
,
Kd
,
T1
: These registers are used to configure the PIDT1 position controller. For the initial con-
figuration, these values can be set to zero. The setup and optimization of the position controller is
described in section 5.4.3.
PositionErrorLimit
: This parameter defines the maximum allowed position error. If the position error
exceeds this limit, the axis is disabled and a
PositionErrorLimit
error is issued. This is an important
parameter which helps to protect the machine in case of a malfunction. Set this parameter as small
as possible without causing faulty activation of the error. Typical values are 0.1mm to 0.5 mm for
linear axes and 0.1 degree to 1.0 degree for rotational axes.
IntegratorOutputLimit
: This parameter restricts the current of the integral term. It is recommended
to set this value to about 40% to 80% of the nominal current.
Filters
: Filters can be used to optimize the stability of the controller loop. See section 5.4.5 for more
information. For the initial setup the
Type
of the filters should be set to
bypassed
.
Warning
Warning
PositionErrorLimit
must be configured correctly before the drive is enabled the first time
to protect the axis.
5.2.7 Axis[].Parameters.Commutation
Commutation
is the process of applying current to the phases in the right order to generate motion. For
brushed DC-Motors, commutation is ensured mechanically by contacting the correct winding with the
brush. For synchronous AC motors, commutation has to be performed electronically, in most cases
based on the encoder position.
For electronic commutation it is crucial to initially determine the orientation between the electrical
phases (stator) and the magnetic poles (rotor). The process to find this orientation is called
phasing
.
With the following parameters, the phasing process can be configured:
PhasingMethod
: This parameter selects the phasing method with the following choices (see also
Figure 41):
NoPhasing
: This method is used if
Axis[].Motor.Type
=
DC
or if a motor with an absolute encoder
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