AKD User Guide | 14 Tuning Your System
Most servo systems require some level of tuning (setting up the desired response of the system usually with the
load attached). This can be done through several methods available within AKDWorkBench.
Slider Tuning - Slider tuning offers a very simplistic approach to tuning and can get you underway quickly. With
this method, just the proportional and integral gains are adjusted based on the desired bandwidth you wish to
achieve. You can take into account your load inertia if it is known. None of the Bi-quad filters are impacted by the
slider tuning.
Auto Tuner - This is an easy way to get a more sophisticated tuning accomplished. The details of how auto-
tuning works are included in the advanced section of this subject. However, the autotune approach is a simple
one-button solution that lets the system configure all of the tuning parameters for you. The autotuner is a robust
solution to get your sytem tuned and ready to operate in a wide variety of mechanical configurations and loads.
Manual Tuning - Certain applications may require manual tuning where you set the gains and filters based on
the specific performance you are looking for. You may also need to "tweak" the tuning that was set up in either
the slider or autotune section to optimize your application performance.
14.1 Slider Tuning
This view allows you to vary the tuning of your drive using the slider.
14.1.0.1 Gentle, Medium, and Stiff
These buttons select three of the most common bandwidths:
l Gentle works in all but the most challenging situations.
l Medium is the default and works in most situations.
l Stiff works for unloaded motors.
14.1.0.2 The Slider
As you drag the slider to the right, the stiffness increases. In many situations, you cannot drag the slider fully to
the right side because the system will become unstable.
14.1.0.3 Inertia Ratio
If you know the inertia ratio of your load, then entering it can improve the performance of your system. If you do
not know the inertia of your load then WorkBench will assume a ratio of 1:1, which will give good performance in
many configurations. The inertia ratio is the ratio of your load with respect to the inertia of your motor.
14.2 Load Inertia
The inertia ratio is the ratio of the load with respect to the inertia of the motor. If you know the inertia ratio of the
load, then entering it can improve the performance of your system. If you do not know the load inertia, then Work-
Bench assumes a ratio of 1:1, which will give good performance in many configurations.
14.3 Using the Autotuner
14.3.1 Overview
The AKD Autotuner makes it easy and fast to tune your servo system. The advanced technology in the AKD
Autotuner achieves high performance and stability for both simple and complicated loads. The Autotuner can
work in a “one button” mode that requires no decisions from the user. It can also be set up in specific modes to
control how the Autotuner operates for specific requirements. Finally, the Autotuner collects frequency response
data (a Bode plot) that can be used for advanced analysis.
The Autotuner will not work reliably on a vertical axis since the motor may rest
against an end stop; in this case, the inertia will not always be correctly identified.
142 Kollmorgen | December 2010
To Next Page
Loading...
