Torque Control Gain Adjustment - Mitsubishi Electric 800 Series Instruction Manual

6.5

Torque control gain adjustment

Sensorless Sensorless Sensorless PM PM PM
Operation is normally stable enough in the initial setting, but some adjustments can be made if abnormal vibration, noise or
overcurrent occur for the motor or machinery.
Pr.
824 Torque control P gain 1 (current loop
G213 proportional gain)
825 Torque control integral time 1 (current
G214 loop integral time)
834 Torque control P gain 2 (current loop
G313 proportional gain)
835 Torque control integral time 2 (current
G314 loop integral time)
 Current loop proportional (P) gain adjustment (Pr.824)
• The 100% current loop proportional gain is equivalent to 1000 rad/s.
• For ordinary adjustment, try to set within the range of 50% to 500%.
• Set the proportional gain for during torque 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 (current loop proportional gain) and Pr.835 Torque control integral time 2
(current loop integral time) if the gain setting needs to be switched according to application or if multiple motors are
switched by a single inverter.
• Pr.834 and Pr.835 is enabled when the second function selection (RT) signal is turned ON.
NOTE
• The RT signal is a second function selection signal which also enables other second functions. (Refer to
• To assign the RT signal, set "3" in any parameter from Pr.178 to Pr.189 (Input terminal function selection).
 Adjustment procedure
Adjust if any of phenomena such as unusual vibration, noise, current or overcurrent is produced by the motor or machinery.
1.
Change the Pr.824 setting while checking the conditions.
124
6. Torque Control
6.5 Torque control gain adjustment
Name Initial value
100%
5 ms
9999
9999
Setting
range
0% to 500% Set the current loop proportional gain.
0 to 500 ms Set current loop integral compensation time.
Set the current loop proportional gain when RT signal is
0% to 500%
ON.
9999 The Pr.824 setting is applied to the operation.
Set the current loop integral compensation time when
0 to 500 ms
RT signal is ON.
9999 The Pr.825 setting is applied to the operation.
Description
page 298.)