Current Int Gain Parameter
The Current Int Gain parameter located in the Level 1 Vector Control Block is factory preset at 150 Hz. This setting is suitable for essentially all systems. DO NOT CHANGE WITHOUT FACTORY APPROVAL.
Speed Prop Gain Parameter
The Speed Prop Gain parameter located in the Level 1 Vector Control Block is factory set to 10. This gain may be increased or decreased to suit the application. Increasing the Speed Prop Gain parameter will result in faster response, excessive proportional gain will cause overshoot and ringing. Decreasing the Speed Prop Gain parameter will cause slower response and decrease overshoot and ringing caused by excessive proportional gain.
Speed Int Gain Parameter
The Speed Int Gain parameter located in the Level 1 Vector Control Block is set to 1 Hz and may be set at any value from zero to 9.99 Hz. See also, PI Controller later in this section.
Setting the Speed Int Gain parameter to 0Hz removes integral compensation that results in a proportional rate loop. This selection is ideal for systems where overshoot must be avoided and substantial stiffness (ability of the controller to maintain commanded speed despite varying torque loads) isn’t required.
Increasing values of the Speed Int Gain parameter increases the low frequency gain and stiffness of the controller, an excessive integral gain setting will cause overshoot for transient speed commands and may lead to oscillation. Typical setting is 4 Hz. If the Speed Prop Gain parameter and the Speed Int Gain parameter are set too high, an overshoot condition can also occur.
To manually tune the control, the following procedure is used:
1.Set the speed Int Gain parameter = 0 (remove integral gain).
2.Increase the Speed Prop Gain parameter setting until adequate response to step speed commands is attained.
3.Increase the Speed Int Gain parameter setting to increase the stiffness of the drive or its’ ability to maintain speed with dynamic load changes.
Note: It is convenient to monitor speed step response with a strip chart recorder or storage oscilloscope connected to
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