Common mode noise characteristics of resonant converters

摘要

This paper investigates the common mode (CM) noise characteristics of resonant converters. Noise sources of CM EMI in isolated resonant converters were identified and analyzed. The operating point of the resonant converter has significant impact on CM noise of the converter. Utilizing the leakage inductance in the power transformer as the resonant inductor can reduce the high-frequency CM noise of some types of resonant converters. However, utilizing leakage inductance may limit the low-frequency reduction while adopting the CM noise reduction techniques.