Yaskawa Sigma-5 User Manual: Design and Maintenance - Rotary Motors - Manual (Page 198)

5.9 Compatible Adjustment Function
5-61
Adjustments
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 due to torque saturation during acceleration or deceleration. The mode
switch function suppresses torque saturation and eliminates the overshooting of the 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 Pn10D.
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 when speed loop gain is
increased.
Without Mode Switching With Mode Switching
Overshoot
Overshoot
Motor
rotational
speed
Time
Motor
rotational
speed
Time
Speed reference
Speed Motor
rotational
speed
Time
P Control PI Control
Pn10D
PI
Without Mode Switching With Mode Switching
Motor
rotational
speed
Speed reference
Long Settling Time
Increase speed loop gain
Settling time
Motor
rotational
speed
Overshoot
Overshoot
Motor
rotational
speed
Time
Motor
rotational
speed
Time
Time