How to match the common mode inductor of a power FTU to a feeder scenario?

In feeder scenarios, common-mode interference has a wide spectrum and high energy, requiring targeted matching of common-mode inductors. For low-frequency interference (10kHz-1MHz), a CMZ7060A-701T high-current inductor (700μH/10A) with a saturation current of 15A is selected. For mid-frequency interference (1MHz-30MHz), a CMZ3225A-510T (510μH/2A) with a self-resonant frequency above 30MHz is selected. For high-frequency interference (30MHz-100MHz), a CML4532A-101T (100μH/1A) is selected, paired with a PBZ1608E600Z0T ferrite bead. During installation, the common-mode inductor should be placed close to the interference source, with a lead length of less than 5mm, and grounded with copper underneath. Through spectrum matching, the common-mode rejection ratio is greater than 40dB across the entire frequency band from 10kHz to 100MHz, meeting the EN55032 Class A conducted emission requirements and passing the IEC 61000-4-6 10V conducted immunity test.