Measurement of DC-side Electromagnetic Noise inside Photovoltaic Power Converters

Electromagnetic interference of photovoltaic (PV) Power Conditioning System (PCS) is a serious problem for the electromagnetic environment. For this problem, the International Special Committee on Radio Interference (CISPR) is discussing to determine a guideline of noise evaluation method and its regulation value for this issue. In the guideline, there are some noise evaluation methods for the PCS, but the evaluation method of conducted noise for a system with multiple power converters connected has never been discussed. The noise measurement in such a system requires the evaluation of conducted noise originating from both DC/DC converters and DC/AC converters. In this paper, the influence of connecting Line Impedance Stabilization Network (LISN) between DC/DC and DC/AC converter was clarified by using common-mode circuit analysis.