7.GENERAL GAIN ADJUSTMENT

(c)Adjustment description

1)Position control gain 1 (PG1: parameter No. 6)

This parameter determines the response level of the position control loop. Increasing PG1 improves trackability to a position command but a too high value will make overshooting liable to occur at the time of settling.

PG1 guideline

 

 

VG2 setting

 

1

to

1

 

 

 

 

( 3

5 )

(1 load inertia moment ratio)

 

 

 

 

 

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)

 

 

VG2 setting

 

 

 

(1 ratio of load inertia moment to motor inertia moment) 2

 

 

 

 

 

3)Speed integral compensation (VIC: parameter No. 38)

To eliminate stationary deviation against a command, the speed control loop is under proportional integral control. For the speed integral compensation (VIC), 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:

VIC setting(ms)

2000 to 3000

VG2 setting/(1 GD2 setting 0.1)

 

 

 

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Mitsubishi Electronics MR-J2S- A instruction manual General Gain Adjustment