Digital filter tuned according to spectral analysis of direct drive to reduce mechanical resonance effect

Review of the filter structures and spectral analysis algorithms was done. Digital filters allow filtering the speed signal in control loop of direct drive with a mechanical resonance. The analogue filter equations were transformed into digital filters to enable tune them in real time. Spectral analysis with additional algorithm allows to determine the mechanical resonance frequency of multi-mass system. Determination of resonance frequencies allow for proper tune the digital filter. This paper presents selected algorithms of determine signal spectrum. In order to determine the mechanical resonance frequency from the whole spectrum, it is require to use an additional algorithm that was omitted from the consideration. Filters were tuned according to frequency characteristics of the object.