Lenze AC Tech PositionServo 940, Руководство пользователя

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S94P01C -e1
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Note
The following four position gain settings are only active if the drive is
operating in Position mode. They have no effect in Velocity or Torque
modes.
6.9.3 Position P-gain (proportional)
Position P-gain adjusts the system’s overall response to position error. Position
error is the difference between the commanded position of the motor shaft and the
actual shaft position. By adjusting the proportional gain, the bandwidth of the drive is
more closely matched to the bandwidth of the control signal, ensuring more precise
response of the servo loop to the input signal.
6.9.4 Position I-gain (integral)
The output of the Position I-gain compensator is proportional to accumulative error
over cycle time, with I-gain controlling how fast the error accumulates. Integral gain
also increases overall loop gain at the lower frequencies, minimizing total error. Thus,
its greatest effect is on a system running at low speed, or in a steady state without
rapid or frequent changes in position.
6.9.5 Position D-gain (differential)
The output of the Position D-gain compensator is proportional to the difference
between the current position error and the position error measured in the previous
servo cycle. D-gain decreases the bandwidth and increases the overall system
stability. It is responsible for removing oscillations caused by load inertia and acts
similar to a shock-absorber in a car.
6.9.6 Position I-limit
The Position I-limit will clamp the Position I-gain compensator to prevent excessive
torque overshooting caused by an over accumulation of the I-gain. It is defined in
terms of percent of maximum drive velocity. This is especially helpful when position
error is integrated over a long period of time.
6.9.7 Gain Scaling Window
Sets the total velocity loop gain multiplier (2 n ) where n is the velocity regulation
window. If, during motor tuning, the velocity gains become too small or too large,
this parameter is used to adjust loop sensitivity. If the velocity gains are too small,
decrease the total loop gain value, by deceasing this parameter. If gains are at their
maximum setting and you need to increase them even more, use a larger value for
this parameter.