Design Considerations When Applying Various LV ASD Topologies to Meet Harmonic Compliance

To limit the harmonic distortion produced by adjustable speed drives (ASDs), manufacturers have introduced several methods of both passive and active harmonic mitigation. Users of ASDs however, who are faced with the various options often find it difficult to select the most appropriate one for their particular application. Using computer simulation and laboratory measurements, this paper analyzes the most common passive solutions for low voltage (LV) applications which include ac line reactors or dc link chokes, phase shifting to produce multi-pulse ASDs and inline passive harmonic filters. Various design considerations, particularly related to power system parameters, are addressed.