Setting
up Compax3
Positioning via digital I/Os
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Resolution
The less precise the resolution, the higher the quantization noise on the velocity
signal.
Noise
The feedbacks have different levels of analog noise, which have a negative effect
on the control. The noise can be dampened with the aid of filters in the actual value
acquisition, however at the cost of the controller bandwidth.
For comparison, the noise of the actual velocity value at standstill of two different
feedbacks is displayed.
Resolver: 1 period/revolution
SinCos: 1024periods/revolution
Typical problems of a non optimized control
In this chapter you can read about:
Too high overshoot on velocity .......................................................................................................126
Increased following error .................................................................................................................127
Instable behavior .............................................................................................................................127
Upon first setup of a control, the controller is normally not able to meet all
application requirements at once. Typical problems may be:
Too high overshoot on velocity
1)
2)
1) Actual
velocity
2) Setpoint
velocity
