Mach-DSP User’s Manual
Document Number: MACH-DSP-9021
Page 87
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As was done in Step W above, you should re-check the large-signal performance after
tuning for small signals. In the screen shot below, you will see that we have set the
time-base for 500 microseconds per division, and set the Position Scale Factor, Error
Scale Factor, and Integration Scale Factor as necessary to view a much larger
waveform. We have also set the Test Signal Generator to produce waves greater than
18 degrees.
With this large squarewave input, there is overshoot present. This can be seen not only
in the Position Error signal (blue trace) but also in the Integrated Error signal (green
trace). This overshoot is caused by the fact that the power amplifier has become
saturated. This is indicated by the yellow blocks that are illuminated in the status area.
This overshoot can be eliminated by adjusting the Slew-rate limiter, as described in
Step W. But before doing that, it will be useful to set the Anti-Windup amount.
In the screen shot below, you will see that we have set the Anti-Windup gain to 0.
