Mains harmonic reduction circuits using non linear inductances

Regulations like IEC 1000-3-2 impose limits on the line input current harmonics. Passive solutions to obtain mains harmonic reduction still dominate the consumer and PC market segment. Some inductors used in practical designs operate in the saturation region even at power levels to be tested for compliance. On the other hand, nearly all publications dealing with design of the passive MHR circuits assume a linear inductor. This paper investigates the usefulness of non linear inductors in passive MHR circuits by extracting the nonlinearity, measuring the compliance, modeling the inductor by an appropriate fit function and extrapolating the design to other power levels