Problems using LISN in EMI characterization of power electronic converters

Line impedance stabilisation networks (LISNs) are used in conducted disturbance measurements for reproducibility and standard experiments. However, depending on topology choice and electrical environment, the behavior of this device might generate errors. LISN tasks are recalled with respect to corresponding standards. Theoretical studies of single and double cell LISNs are made (with respect to input and output variable impedance). It is shown that single cell devices might be quite susceptible with respect to line impedance. Converter input impedance effect is underlined. Besides, depending on LISN characteristics, the addition of passive components between the measurement device and the converter induces behavior changes. This might even disturb converter behavior itself. Finally, practical measurement condition effects are discussed.