Torque Control By Real Sensorless Vector Control, Vector Control; Torque Control - Mitsubishi Electric FR-A720-0.4K Instruction Manual

4.5 Torque control by Real sensorless vector control, vector
control
Purpose
Selection of torque command
source and setting of torque
command value
Prevent the motor overspeed
Improve torque control accuracy
Stabilize the torque detection signal Torque detection filter
4.5.1

Torque control

Torque control is exercised to develop torque as set in the torque command.
The motor speed becomes constant when the motor output torque and load torque are balanced.
For torque control, therefore, the speed is determined by the load.
For torque control, the motor gains speed as the motor output torque becomes greater than the motor load.
To prevent overspeed, set the speed limit value so that the motor speed does not increase too high.
(Torque control is disabled under speed limit since speed control is exercised.)
When speed limit is not set, the speed limit value setting is regarded as 0Hz to disable torque control.
(1) Block diagram
Terminal 1
[Pr. 868 = 3, 4]
Torque
setting
filter
Parameter
[Pr. 805, Pr. 806]
CC-Link
(FR-A7NC/FR-A7NCE)
16bit digital input
(FR-A7AX)
Pulse train
(FR-A7AL)
Actual speed or estimated speed
< Speed limit value
Actual speed or estimated speed
Speed limit value
+
A
Speed
-
limit
value
Parameter that must be Set
Torque command
Speed limit
Gain adjustment for

torque control

Terminal 1 bias [C16,C17 (Pr. 919)]
Terminal 1 gain [C18,C19 (Pr. 920)]
RT
[Pr. 826 = 9999]
[Pr. 826]
[Pr. 74]
[Pr. 826 = 9999]
[Pr. 836 = 9999]
RT
[Pr. 836]
[Pr. 74]
[Pr. 836 = 9999]
RT
+
-
RT
Speed control
(proportional
control)
[Pr. 800 = 1]
[Pr. 800 = 11]
Torque control by Real sensorless
vector control, vector control
Pr. 803 to Pr. 806
Pr. 807 to Pr. 809
Pr. 824, Pr. 825, Pr. 834, Pr. 835
Pr. 827, Pr. 837
Constant power range
Torque command
torque characteristic selection
source selection
[Pr. 803]
[Pr. 804]
Torque control
P gain 1
[Pr. 824]
Torque control
integral time 1
[Pr. 825]
Torque control
P gain 2
[Pr. 834]
Torque control
integral time 2
[Pr. 835]
Torque detection filter
RT
[Pr. 827]
RT
[Pr. 837]
Speed detection filter
RT
Speed
estimation
RT
Refer to Page
125
127
130
144
+
Encoder
Motor
+
+
+
[Pr. 823]
[Pr. 833]
119
4