Steinmetz Circuit Influence on the Electric System Harmonic Response

Single-phase loads such as traction systems cause voltage asymmetries and damage power quality. Reactors suitably connected to single-phase loads are used to reduce this unbalance. The set formed by reactors and single-phase loads is more commonly known as Steinmetz circuit. In nonsinusoidal conditions, the resonance between the reactors of the Steinmetz circuit and the system reactances can worsen the harmonic disturbances. This paper studies the harmonic response of an electric power system in the presence of a Steinmetz circuit. The study allows the parallel resonance to be predicted. The obtained results are validated with experimental measurements.