Higen FDA7000 Series, Operation Manual

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5. Servo operating
4-21
- Velocity integral time constant(P03-06) is gradually decreased in order to reduce velocity
ripple and reduce over / under shoot in most applications. However, if the value of speed
integral time constant is set too small, strange sounds and vibrations may occur in the
motor (machine). In addition, if the load is very large (more than 8 times), set the speed
integral time constant to a large value and reduce the speed control proportional gain value.
2) Important points when using Gain 1 and Gain 2 in speed control mode
- Gain switching method by contact
: When sound is generated when the motor is stopped, the contact can be selected to apply
high gain during normal operation and the contact can be selected to apply low gain after
motor stop. In this case, using P03-22 (Stop speed vibration suppression) produces a
similar effect.
- Gain switching method by speed
: The gain switching method by contact is aimed at setting low gain in the motor stop area,
while the speed gain switching method requires high-precision machining which requires
high gain at low speed and low gain at high speed. This can be used for machines.
- Gain switching method by torque
: If the gain is set high when the servo motor is operated with high torque, it may cause
vibration. In addition, when the servo motor is operated at low torque, the low gain causes
poor speed ripple and control performance. In this case, by using the gain switching
method for torque, stable and excellent control performance can be realized in the whole
operating area.
3) Important points when in position control mode
- Position control proportional gain gradually increases to the value that undershoot does not
occur when abnormal sound, vibration and target position are reached in the motor
(machine). In addition, increase the speed control proportional gain value and inertia ratio
to a value where noise does not occur from the motor (machine).
- Responsiveness is improved by decreasing the value of the speed integral time constant.
However, if it is made too small, it can cause vibration in the motor (machine), and if it is too