Electronic devices which are fed from the grid and have a rectifier frontend, such as motor drives, uninterruptible power supplies, AC voltage regulators are commonly used. These devices which draw non-linear current from the grid by nature cause the nonlinear voltage drops along the supply line. In this case, if precautions are not taken, power quality problems also appear for the other loads fed from the same line. Level of the harmonic currents drawn can be reduced to specific level by using reactors with silicon steel core at the input of the line frequency converters. Selection of the core material with the sizing of the reactors becomes the determiner of the harmonic reducing ability and of the losses of the reactor. In this study, three reactors with different core materials are designed for a specific line current value. In order to see the inductance value variations depending on the load level of the designed reactors, the parametric analysis have been performed by the finite element method. As a result of analysis, data like the reactor inductance stability, the losses and the standards compliance have been presented comparatively. Magnetic circuits have been modeled with Ansys-Maxwell and co-simulated with the Simplorer to see the realistic behaviors of the reactors.