Phase-saving lowpass filters for drive control in conjunction with a high level of control dynamics

The PDT2 filtering element (PDT2) and a Cauer filter (C2) are employed for use in control tasks of automation engineering, in particular for a filter connected downstream of a rotational speed controller. For tasks in control engineering, these have the advantage of a higher level of robustness, since a large frequency range is filtered, and a substantially smaller phase drop than conventional lowpass filters (PDT2). Consequently, by comparison with the known prior art a loss in dynamics is substantially minimized with these phase-saving lowpass filters, and an optimum is achieved in robustness and dynamics.