Mitsubishi Electric FR-A800, Instruction Manual

Page: 324 / 1042

Torque control under Real sensorless vector control and vector control Parameters
5 - 144
5.4.6 Torque control gain adjustment
Operation is normally stable enough in the initial setting, but some adjustments can be made if if ab-
normal vibration, noise or overcurrent occur for the motor or machinery.
Current loop proportional (P) gain adjustment (Pr. 824)
●
The 100% current loop proportional gain is equivalent to 1000 rad/s during Real sensorless vector
control, and to 1400 rad/s during vector control.
●
For ordinary adjustment, try to set within the range of 50 to 500%.
●
Set the proportional gain for during speed control.
●
If setting value is large, changes in current command can be followed well and current fluctuation
relative to external disturbance is smaller. If the setting value is however too large, it becomes
unstable and high frequency torque pulse is produced.
Current control integral time adjustment (Pr. 825)
●
Set the integral time of current control during torque control.
●
Torque response increases if set small; current however becomes unstable if set too small.
●
If the setting value is small, it produces current fluctuation toward disturbance, decreasing time
until it returns to original current value.
Using two types of gain (Pr. 834, Pr. 835)
●
Use Pr. 834 "Torque control P gain 2", Pr. 835 "Torque control integral time 2" if the gain setting
needs to be switched according to application or if multiple motors are switched by a single
inverter.
●
The Pr. 834 and Pr. 835 settings are valid when the second function selection (RT) signal is ON.
Pr. Name
Initial
value
Setting
range
Description
824
G213
Torque control P gain 1
(current loop proportional
gain)
100% 0 to 500%
Sets the current loop proportional gain.
100% is the equivalent to 2000 rad/s.
825
G214
Torque control integral time 1
(current loop integral time)
5 ms 0 to 500 ms Sets current loop integral compensation time.
834
G313
Torque control P gain 2 9999
0 to 500%
Sets the current loop proportional gain when RT
signal is ON.
9999 The Pr. 824 setting is applied to the operation.
835
G314
Torque control integral time 2 9999
0 to 500 ms
Sets the current loop integral compensation time
when RT signal is ON.
9999 The Pr. 825 setting is applied to the operation.
NOTES The RT signal is a second function selection signal. The RT signal also enables other second func-
tions. (Refer to page 5-428.)
RT signal is assigned to the terminal RT in the initial status. Set "3" in any of Pr. 178 to Pr. 189 (input
terminal function selection) to assign the RT signal to another terminal.
Sensorless Sensorless Sensorless Sensorless Sensorless Sensorless Sensorless Sensorless Sensorless Vector Vector Vector