MITSUBISHI ELECTRIC MR-J2S- A - Manual (Page 182)

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7. GENERAL GAIN ADJUSTMENT
(c) Adjustment description
1) Position control gain 1 (parameter No. 6)
This parameter determines the response level of the position control loop. Increasing position
control gain 1 improves track ability to a position command but a too high value will make
overshooting liable to occur at the time of settling.
Position control
gain 1 guideline Speed control gain 2 setting
(1 ratio of load inertia moment to servo motor inertia moment)
(
to
1
5 1
3 )
2) Speed control gain 2 (VG2: parameter No. 37)
This parameter determines the response level of the speed control loop. Increasing this value
enhances response but a too high value will make the mechanical system liable to vibrate. The
actual response frequency of the speed loop is as indicated in the following expression.
Speed loop response
frequency(Hz) Speed control gain 2 setting
(1 ratio of load inertia moment to servo motor inertia moment) 22
3) Speed integral compensation (parameter No. 38)
To eliminate stationary deviation against a command, the speed control loop is under
proportional integral control. For the speed integral compensation, set the time constant of this
integral control. Increasing the setting lowers the response level. However, if the load inertia
moment ratio is large or the mechanical system has any vibratory element, the mechanical
system is liable to vibrate unless the setting is increased to some degree. The guideline is as
indicated in the following expression.
Speed integral
compensation setting(ms) 2000 to 3000
Speed control gain 2 setting/ (1 ratio of load inertia moment to
servo motor inertia moment 2 setting 0.1)
7.4 Interpolation mode
The interpolation mode is used to match the position control gains of the axes when performing the
interpolation operation of servo motors of two or more axes for an X-Y table or the like. In this mode, the
position control gain 2 and speed control gain 2 which determine command track ability are set manually
and the other parameter for gain adjustment are set automatically.
(1) Parameter
(a) Automatically adjusted parameters
The following parameters are automatically adjusted by auto tuning.
Parameter No. Abbreviation Name
34 GD2 Ratio of load inertia moment to servo motor inertia moment
35 PG2 Position control gain 2
37 VG2 Speed control gain 2
38 VIC Speed integral compensation