Does the conducted interference of the BMS control board in the 150kHz-30MHz frequency band exceed the limit of GB/T18655 Class 3?

Excessive conducted interference in this frequency band typically originates from high-frequency noise in switching power supplies and digital circuits, particularly insufficient power supply port filtering. Effective suppression requires designing a composite filter network at the input. For example, using CMZ series surface-mount common-mode inductors to attenuate common-mode noise, while combining them with π-type filters to handle differential-mode interference. For the high-frequency range above 10MHz, MLCC capacitors with excellent high-frequency characteristics and CBL series ferrite beads should be selected to form a wide-bandgap attenuation, ensuring that the average interference voltage of each sub-band is below the stringent Class 3 limit. Proper filter layout and grounding are crucial for success.