Torque control under Real sensorless vector control and vector control
Troubleshooting in torque control
Torque control does not
When a small torque
command is given, the
motor rotates in a
direction opposite to
the start signal.
Torque control cannot
operate normally during
The motor vibrates.
Output torque is
nonlinear for the torque
Parameters referred to
Pr. 178 to Pr. 189
C16 to C19
5 - 146
There is incorrect phase
sequence between the
motor wiring and encoder
Pr. 800 "Control method
selection" setting is applied.
Speed limit value has not
Torque command varies.
The torque command and
the torque recognized by the
inverter are different.
Torque fluctuation due to
motor temperature variation
The option to be used and
parameter settings do not
Torque offset calibration is
Speed limit is operating.
(Speed limit may operate
because the speed limit
value will increase or
decrease according to
time setting of Pr. 7 and Pr. 8
when Pr. 807 = "0 or 2".)
Troubleshooting during torque control
PWM frequency selection
(input terminal function selection)
Control method selection
Speed limit selection
(torque setting voltage (current) bias/gain)
Check the wiring. (Refer to page 2-67.)
Check the setting of Pr. 800. (Refer to page 5-56.)
Set speed limit value. (If speed limit value is not
input, it becomes 0 Hz by default and the motor
does not run.)
Check that the torque command sent from the
controller is correct.
Set Pr. 72 "PWM frequency selection" lower.
Set Pr. 826 "Torque setting filter 1" higher.
Re-calibrate the C16 "Terminal 1 bias command
(torque)", C17 "Terminal 1 bias (torque)", C18
"Terminal 1 gain command (torque)", and C19
"Terminal 1 gain (torque)".
(Refer to page 5-409.)
Select the magnetic flux observer by Pr. 95 "Online
auto tuning selection". (Refer to page 5-465.)
Correctly set Pr. 862 "Encoder option selection"
according to the option to be used (refer to page
Re-calibrate C16 "Terminal 1 bias command
(torque)" and C17 "Terminal 1 bias (torque)". (Refer
to page 5-409.)
Set the acceleration/deceleration time shorter.
Alternatively, set acceleration/deceleration time to
"0". (Speed limit during acceleration/deceleration
is determined by the speed limit for constant
Return Pr. 854 "Excitation ratio" to the initial value.