The invention discloses a conductive common-mode / differential-mode
noise separation method, belonging to the technical field of conductive
electromagnetic compatibility noise measurement. Radiofrequency current probe measurement and
software separation calculation are combined, and the method is suitable for conductive interference measurement on a
single phase line. The method comprises the following measuring steps: I, directly measuring a
phase line, center line and common-mode
conducted interference spectrum by using a radiofrequency current probe, connecting the output end of the current probe to a
spectrometer through a
coaxial line, and driving the
spectrometer to work in a
peak detection mode; II, calibrating interference spectrum data obtained in the step I, and measuring the transmission
admittance of the current probe and the
coaxial line used in the step I by using a vector network analyzer; III, putting the corrected data IL, IN and ICM into a formula to obtain a differential-mode
current spectrum IDM so as to obtain the interference
voltage in a differential mode and a common mode. By adopting a test method, the
conducted interference spectrum on each line can be measured rapidly, and separation of common-mode and differential-mode interference is realized. The method is mainly applied to online measurement of
electromagnetic compatibility noise.