CSDP Plus Servo Drive User Manual

SEt-02 Speed Loop Proportional Gain
• Setting range: 0 to 1500 N . m . s
• User Default: 80
• Changes anytime
Speed loop proportional gain determines the response of the speed
control. Set the highest value as long as vibration does not occur at the
system. The upper limit will be determined according to the natural
frequency and rigidity of the system. If the inertia of the load grows,
raise the value.
Speed loop proportional gain is scaled to the motor’s rotor inertia.
If load condition is equivalent to the operating condition, the gain
value for the load inertia 10 times larger than that of a 1.5 kW motor is
similar to the load inertia 10 times larger than that of a 3 kW motor.
If the proportional gain (P) is lowered while the integral gain (I)
remains the same or the proportional gain is kept the same while the
integral gain is lowered, the response changes in the order shown in
the above diagram. The time to reach the target speed in the early
stage is determined by the proportional gain and the time to catch up
with the end target from the point past 50% of the target speed is
determined by the integral gain. Since the characteristics of these two
gains can’t be regarded separately, tune the proportional gain first and
then integral gain.
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