68
9
639
230
164
25
7500
2700
1765
10
750
270
189
26
8612
3100
1765
11
889
320
222
27
9445
3400
∞
12
1056
380
268
28
10278
3700
∞
13
1250
450
340
29
11112
4000
∞
14
1500
540
360
30
12500
4500
∞
15
1667
600
392
31
13889
5000
∞
Stiffness should be adjusted according to the actual requirement.
If response is too slow
increase stiffness. If oscillation or noise increases
reduce stiffness.
If the command from the controller (e.g. PLC) is unreasonable or inappropriate for the machine, some filters
should be modified in order to reduce oscillation (see chapter 7.3 manual tuning).
Information
When the stiffness setting or the inertia ratio increases Kvp to a value of greater than 4000, it’s
not useful to increase stiffness any more, and bandwidth will be decreased if the inertia ratio is
further increased. If changing stiffness via communication, WriteFUN_CTL(3041.05) must be
set to 1 first, and be set back to 0 after stiffness has been changed.
7.2 Manual tuning
If the auto-tuning function does not support the actual application, or if the application has a gap, inertia
changes or a very soft connection, manual tuning is the right choice.
The manual tuning process makes use of test motion. Match the controller to the actual application on the
basis of experience with the application and a given scope of data by changing loop gain and filter settings.
Since current loop parameters are calculated internally based on the motor parameters, there is normally no
need to set current loop parameters manually.
7.2.1 Tuning of the velocity loop
Steps required for adjustment:
Ensure limiting of velocity loop bandwidth
Velocity loop bandwidth limits position loop bandwidth and thus adjustment of velocity loop bandwidth is
important.
Limitation of velocity loop bandwidth can be judged from several viewpoints.
1) According to oscillation and noise sensed with the finger and the ears: This method is based on
experience, but it’s efficient. The user can listen to or touch the machine, at the same time increasing and
reducing the kvp. When an acceptable maximum kvp value is found, the current setting can be specified as
the maximum velocity loop bandwidth.
2) According to the scope image: The user can create a jump command for velocity control and sample
actual velocity and current while changing kvp. The right velocity curve should quickly fulfil the command
without oscillation and unusual noise.
