Siemens SINUMERIK 828D Turning, Руководство по эксплуатации функций

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G2: Velocities, setpoint / actual value systems, closed-loop control
7.6 Optimization of the control
Basic Functions
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
383
MD32800 $MA_EQUIV_CURRCTRL_TIME
but are enabled as before in the drive.
Limitation to stiff machines
Experience has shown that this expenditure is only worthwhile in the case of very stiff machines, and requires
appropriate experience. The elasticities of the machine are often excited due to the injection of the torque so
strongly that the existing vibrations neutralize the gain in contour accuracy.
In this case, it would be worth trying the use of Dynamic Stiffness Control (DSC) as an alternative:
MD32640 $MA_STIFFNESS_CONTROL_ENABLE = 1
7.6.2 Position controller, position setpoint filter: Jerk filter
Application
In some applications, such as when milling sculptured surfaces, it can be advantageous to smooth the position
setpoint curves to obtain better surfaces, due to reduced excitations of machine vibrations.
Functionality
The filter effect of the position setpoints must be as strong as possible without impermissibly affecting contour
accuracy.
The smoothing behavior of the filter must also be as "symmetrical" as possible, i.e., if the same contour was to be
traveled in both forward and reverse, the characteristic rounded by the filter should be as similar as possible in
both directions.
The effect of the filter can be monitored by means of the effective servo gain factor (K
V
), which is displayed on
the Axis service screen form. The filtering effect rounds the position setpoints slightly, thus reducing the path
accuracy so that with increasing filter time a smaller effective servo gain factor (K
V
) is displayed.
Filter enable with MD32402
With the machine data:
MD32402 $MA_AX_JERK_ENABLE
the position setpoint filter is enabled
and determined using the following definitions:
Note
If DSC is to be activated (MD32640 = 1), no parameters may be assigned for actual-value
inversion in the NC (MD32110 $MA_ENC_FEEDBACK_POL = -1). Otherwise, error 26017
occurs.
In DSC mode, actual-value inversion may only be undertaken in the drive (SINAMICS
parameter p0410).