Study of Back-to-Back Hybrid Filter Applied to a Hot Strip Mill with Cycloconverters

This paper presents an analysis of the back-to-back connection between an active and passive filter in a hot strip mill (HSM) with cycloconverters, in a steel mill located in Vitória Metropolitan Area, ES, Brazil. Through a simulation study, the performance of back-to-back hybrid filter for harmonic compensation and damping of harmonic resonance is evaluated. In addition, the reduction of the effective current in the branches of the passive filtering system is analyzed, in face of a load expansion of the HSM. The obtained results show that the back-to-back filter topology allowed the improvevement of the Power Quality (PQ) and elimination of the overload in the preexisting passive filters with a low rated active filter, when compared to the power system load.