LSIS XDL-L7NH Series, User Manual, Page: 139 / 348

5. Drive Application Functions
5-31
5.10.2
P/PI Control Switching
PI control uses both proportional (P) and integral (I) gains of the speed controller, while P control uses
only proportional gain.
The proportional gain determines the responsiveness of the entire controller, and the integral gain is
used to eliminate an error in the steady state. Too high of an integral gain will result in an overshoot
during acceleration or deceleration.
The PI/P control switching functions are used to switch between the PI and P controls under the
condition of the parameters within the servo (such as torque, speed, acceleration, and position
deviation); specifically, they are used under the following situations:
Speed control: To suppress any overshoot or undershoot during acceleration/deceleration.
Position control: To suppress undershoot during positioning, resulting in a reduced positioning time.
You can accomplish similar effect by setting the acceleration/deceleration of the upper level controller,
the soft start of the servo drive, the position command filter, or etc.
You can configure these settings in the P/PI control switching mode (0x2114). Please see the details
below: Switching to P control by PCON input takes precedence over this setting.
Setting values Setting details
0 Always uses the PI control.
1
Switches to the P control if the command torque is larger than the P
control switching torque (0x2115).
2
Switches to the P control if the command speed is larger than the P
control switching speed (0x2116).
3
Switches to the P control if the acceleration command is larger than the P
control switching acceleration (0x2117).
4
Switches to the P control if the position error is larger than the P control
switching position error (0x2118).
Positioning time
Speed
Time
Overshoot
Motor speed
Speed
Command
Undershoot