YASKAWA E-V Series User Manual page 239

6 Adjustments
6.8.5 Using the Mode Switch (P/PI Switching)
<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 force saturation during acceleration or deceleration.
The mode switch function suppresses force saturation and eliminates the overshooting or undershooting of the
motor speed.
Motor
speed
Using the Speed Reference Level to Switch Modes
With this setting, the speed loop is switched to P control when the value of speed reference input exceeds the
speed set in Pn181.
<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.
Increase speed loop gain
6-58
Without Mode Switching
Overshoot
Undershoot
Time
Speed
Pn181
Without Mode Switching
Speed reference
Motor speed
Motor
speed
Long Settling Time
Overshoot
Motor
speed
Undershoot
Time
With Mode Switching
Motor
speed
Speed reference
P Control PI Control
PI
With Mode Switching
Motor
speed
Settling time
Time
Motor
speed
Time