Yaskawa Sigma II Series SGMVH User Manual
Page 272
9 Adjustments
9.4.5 Using the Mode Switch (P/PI Switching)
9-12
Using the Acceleration Level to Switch Modes
With this setting, the speed loop is switched to P
control when the motor’s acceleration rate exceeds
the acceleration rate set in parameter Pn10E.
Operating Example
If the mode switch function is not being used and the SERVOPACK is always operated with PI control, the speed of the
motor may overshoot or undershoot due to torque saturation during acceleration or deceleration. The mode switch function
suppresses torque saturation and eliminates the overshooting or undershooting of the motor speed.
Using the Error Pulse Level to Switch Modes
This setting is effective with position control only.
With this setting, the speed loop is switched to P control when
the error pulse exceeds the value set in parameter Pn10F.
Operating Example
In this example, the mode switch is used to reduce the settling time. It is necessary to increase the speed loop gain to reduce
the settling time. Using the mode switch suppresses overshooting and undershooting when speed loop gain is increased.
Motor speed
Reference speed
Speed
Motor acceleration
+Pn10E
Acceler-
ation 0
-Pn10E
PI control
PI control
PI
P
P
Overshoot
Without Mode Switching
With Mode Switching
Undershoot
Motor
speed
Time
Motor
speed
Time
Motor
speed
Reference
Speed
Pn10F
Position
error pulse
Time
P control
PI
PI control
Motor speed
Speed
reference
Long settling time
Increase speed loop gain.
Settling time
Motor
speed
Overshoot
Undershoot
Motor
speed
Time
Motor
speed
Without Mode Switching
With Mode Switching