Mitsubishi Electric FR-A700 Technical Manual page 256

(2) Model adaptive speed control [Pr. 877 = 2,
Pr. 828, 881]
The motor's model speed is calculated to provide
feed back to the model side speed controller.
This model speed is also used as the actual speed
controller command. Acceleration/deceleration speed
is limited by model speed calculation with [Pr. 880
Load inertia ratio].
larger value than the actual inertia in [Pr. 880] may
extend the acceleration/deceleration time than the
setting.
The inertia ratio in [Pr. 880] is used for calculation of
the torque current command value given by the
model side speed controller.
The torque current command value of the model side
speed controller is added to the output of the actual
speed controller, and the result is used as the torque
control input.
[Pr. 828] is used for model side speed control (P
control), and the first gain in [Pr. 820] is used for the
actual speed controller. The model adaptive speed
control is valid for the first motor only. When [Pr. 877 =
2], switching to the second motor handles the second
motor as [Pr. 877 = 0].
Model adaptive speed control
+ Model speed
Speed command
control gain
-
(3) Combination of easy gain tuning
The following table indicates the relationships
between the speed feed forward/model adaptive
speed control and easy gain tuning function. Refer to
page 286 for how to adjust the easy gain tuning
function.
[Pr. 880 Load inertia ratio]
[Pr. 820 Speed control P gain 1]
[Pr. 821 Speed control integral time 1]
[Pr. 828 Model speed control gain]
[Pr. 881 Speed feed forward gain]
Therefore, note that setting a
J
Torque coefficient
(J: [Pr. 880] )
1
J s
[Pr. 828]
Model speed
calculation
0
Inertia ratio estimation value found by
Manual input easy gain tuning is displayed.
Manual input enabled only during a stop.
Tuning results are displayed.
Manual input
Write disabled
Tuning results are displayed.
Manual input
Write disabled
Tuning results are displayed.
Manual input
Write disabled
Manual input Manual input
Speed control
+
P gain 1
- [Pr. 820]
Speed control
Actual speed controller
integral time 1
[Pr. 819 Easy Gain Tuning Selection] Setting
1
290
PARAMETER
+
+
Torque
control
+
[Pr. 821]
Speed
estimator
2
Manual input
Tuning results are displayed.
Write disabled
Tuning results are displayed.
Write disabled
Tuning results are displayed.
Write disabled
Manual input
IM