Implementation issues for half-bridge and full-bridge active filters in single phase applications

Active filters are becoming a more and more effective means of eliminating harmonic currents generated by nonlinear loads in distribution systems. In single phase applications two topologies are available: (a) half-bridge, and (b) full-bridge. This paper focuses on the relative merits of both topologies. The performance of each topology is investigated. A detailed analysis is included to highlight their inherent problems and define criteria for the selection of appropriate topology. Moreover, the design of LC filtering stages is investigated in depth. Key experimental results are provided to validate the theoretical concepts.