A new three-input/output characteristics-varying filter in the D-module for direct processing of three-phase signals

This paper proposes a new three-input and three-output characteristics-varying filter in the D-module for direct processing of three-phase signals, which are becoming indispensable for effective active compensation of three-phase power such as harmonics current, negative phase current, reactive power and varying voltage compensations. The filter in the D-module can show different filtering characteristics to positive, negative and zero phase components of three-phase signals and can allow direct processing of the signals based on frequency polarities. The filter in the D-module can also change dynamically its filtering characteristics by simply injecting a shift-signal to itself. These filtering effects are obtained in a very simple manner using the D-module. A new unified analysis of attractive general characteristics of the proposed filter in the D-module is given for its easy designs and realizations as well. Effectiveness of the analysis and usefulness of the filter in the D-module are newly examined and confirmed through experiments. The newly proposed filter in the D-module has potential for a variety of three-phase signal filtering applications.