Addi-Data APCI-8001, Руководство по вводу в эксплуатацию

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6 Settings and plans
After the xPCI-800x hardware and software components have been installed correctly, the axis and motor-
specific settings and plans can be made using the
mcfg.exe TSW program, as described in the following
sections.
6.1 Isolating output for power output stage
It is sometimes necessary to isolate the power output stage only if the control loop is closed. You can do this
using a programmable xPCI-800x digital output, or the release relay provided for this purpose [section 5.2.9],
which is configured with PAE function (MCFG / section 1.7.2.6). This output is activated by closing the control
loop. In addition, this output can be used to control a fail-safe brake. If a speed controller is being used,
however, the amplifier must be disabled, as otherwise the drift may cause torque to build up.
6.2 Determining the PIDF filter parameters
The axis and motor-specific filter parameters kp. ki, kd and kpl can be set empirically or analytically. The
mcfg.exe program offers the option of displaying the system behaviour graphically. This enables the control
response to be assessed accurately. Every time you set the filter parameters, you should check if the
manipulated variable output and the position feedback are being executed with the correct phase angle, as
otherwise the motor axis will immediately drift out of control after the control loop has been closed, if a system
deviation occurs.
For all experimental settings when the motor axis is connected, you must remember that the system may
vibrate at considerable amplitudes and with high accelerations. Any danger to persons or the machine itself
must be prevented by appropriate precautionary measures. Furthermore, a system which initially appears to
be stable may start to oscillate due to excitation.
Possible protective measures are an EMERGENCY STOP switch, decoupling the motor axis from the load,
etc.
Contouring error monitoring is also possible here.
Note: For more information on the PIDF filter, see [PM/section 2.1.2].
6.2.1 Speed controllers
A proportional controller is sufficient to control a control system with a subordinate speed controller. To set
this, first set all filter parameters to zero and
kp to 1, for example. Now you can use kp to vary the setting until
you find a suitable control response.
An additional improvement in the control behaviour can be reached through the velocity pre-control. In order
to determine this value experimentally, the proportional part (kp) is set on 0. When a suitable value is found,
the previously determined value is entered again from kp.
Caution: If kp is set to 0, the axis is not regulated and will only be operated in a controlled way. Thus,
significant deviations between real value and set value are possible. In this situation, the system must be
monitored permanently by the user. Before re-adding the proportional part (kp), the control loop must be
opened as otherwise unexpected axis movement may occur.
By an additional integral part
ki , a permanent control deviation at position control, e.g. the input offset of the
speed controller can be avoided.