Yaskawa G7 Drive - Manual (Page 428)

Varispeed G7 Control Modes
10-
5
With torque control, operate within a speed control range of 1:10 on the regenerative side.
Precautions on Setting Parameters
If the parameters are not set properly, performance may be adversely affected.
• If there is a possibility of starting with the motor already rotating, enable the speed search function (b3-
01=1).
• When lowering a torque limit (L7- ), set it to as high a value as possible within the range allowed by
the system.
• If torque limit acceleration is performed, or if the motor slips at the torque limit causing a CF (control
fault), increase n4-08 (proportional gain of speed estimator) in steps of 5 until acceleration and decelera-
tion are performed smoothly. When n4-08 is increased, the torque reference (U1-09) may oscillate. If so,
increase C5-06 (ASR primary delay time) by about 0.050 s.
Precaution on Torque Accuracy
To ensure torque accuracy within the speed control range of 1:10 when the motor is operated by itself at
the minimum frequency and the torque reference (U1-09) is higher than in the medium- and high-speed
ranges, increase the setting of the torque adjustment gain (n4-17) and adjust the torque reference so that it
is about the same as that in the medium and high speed ranges.
0
100
200
-100
-200
60 6 3 1
0.3
Load torque (%)
Speed (Hz)
Driving torque
Regenerative torque