Mitsubishi Electric FR-A700 EC, Instruction Manual

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Torque control by real sensorless vector control, vector control Parameter
6 - 122
Operation example (when Pr. 804 = 0)
Torque control is enabled if the actual speed is less than the speed limit value. When the actual
speed reaches or exceeds the speed limit value, speed limit operation starts, torque control is
stopped, and speed control (proportional control) starts.
The following shows the operations in response to the analog input command from terminal 1.
1)When STF signal is turned on, the speed limit value is increased according to the time set in
Pr. 7.
2)Speed control operation is performed if the actual speed rises to or above the speed limit
value. OL signal is output during speed limit.
3)When the STF signal is turned off, the speed limit value is decreased according to the time set
in Pr. 8.
4)For torque control, the actual speed becomes constant when the torque command and load
torque are balanced.
5)The motor torque developing direction is determined by the combination of the torque com-
mand input polarity and start signal as indicated in the following table.
I001522E
Fig. 6-36: Transition operation
Torque Command Polarity
Torque Developing Direction
STF signal ON STR signal ON
Positive Forward rotation direction (forward
rotation driving/reverse rotation rege-
neration)
Reverse rotation direction (forward
rotation regeneration/reverse rota-
tion driving)
Negative Reverse rotation direction (forward
rotation regeneration/reverse rota-
tion driving)
Forward rotation direction (forward
rotation driving/reverse rotation rege-
neration)
Tab. 6-22: Motor torque developing direction
STF
(Forward rotation
command)
Time
Speed
Speed
Speed limit value
Pr. 7 Pr. 8
Speed limit operation
(Speed control)
Torque control
operation
Speed limit operation
(Speed control)
Torque
control
operation
Speed limit operation
(Speed control)
ON ON ON
OL
* When the speed limit activates, torque according to the commanded is not developed.
Torque command