6.GENERAL GAIN ADJUSTMENT

(c)Adjustment description

1)Speed control gain 2 (parameter No. 16)

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 setting

 

 

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

 

 

 

 

 

2)Speed integral compensation (parameter No. 17)

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

2000 to 3000

composition setting (ms)

 

 

Speed control gain 2 setting/ (1 ratio of load inertia moment

 

 

 

 

to servo motor inertia moment.)

(2) For position control

(a) Parameters

The following parameters are used for gain adjustment:

Parameter No.

Abbreviation

Name

12

GD2

Ratio of load inertia moment to servo motor inertia moment

13

PG1

Position control gain 1

16

VG2

Speed control gain 2

17

VIC

Speed integral compensation

(b) Adjustment procedure

Step

 

Operation

Description

1

Set an estimated value to the ratio of load inertia moment to servo

 

motor inertia moment (parameter No. 12).

 

 

 

2

Set a slightly smaller value to the position control gain 1 (parameter

 

No. 13).

 

 

 

 

 

 

Increase the

speed control gain 2 (parameter No. 16) within the

Increase the speed control gain.

3vibration- and unusual noise-free range, and return slightly if vibration takes place.

4

Decrease the speed integral compensation (parameter No. 17) within

Decrease the time constant of the speed

the vibration-free range, and return slightly if vibration takes place.

integral compensation.

 

5

Increase the position control gain 1 (parameter No. 13).

Increase the position control gain.

 

If the gains cannot be increased due to mechanical system resonance or

Suppression of machine resonance

 

the like and the desired response cannot be achieved, response may be

Refer to Section 7.2 and 7.3.

6increased by suppressing resonance with adaptive vibration suppression control or machine resonance suppression filter and then executing steps 3 to 5.

7

While checking the settling characteristic and rotational status, fine- Fine adjustment

adjust each gain.

 

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Bose MR-J2S- B instruction manual For position control, Suppression of machine resonance, Refer to .2