Selective active filter with optimum remote harmonic distortion control

This paper presents the calculation methods for the optimization of the different filtering blocks of a selective active filter in order to minimize the active filter inverter size, keeping the harmonic emissions at the limits stated by the applicable regulations. Since it may be necessary to comply with the regulations at a different (remote) place with respect to the active filter location, the optimization method has been extended to this case. In order to validate the simulations, measurements which were made at a real application-an arc furnace-were used. Finally, the simulated results obtained with a optimized remote hybrid selective filter were compared with those obtained when a shunt active filter is installed directly at the place where the harmonic emission regulations must be met. The comparison shows that optimized remote compensation is an alternative to be seriously considered because it allows the installation of the active filter at the source of harmonic injection (distorting load).