Analysis and Design of EMI Filter for High Step-Up Push-Pull Series-Resonant Converter

The electromagnetic interference (EMI) of DC-DC converter is the precondition of reliability for electric vehicle (EV). This paper proposes a design method of EMI filter for high step-up push-pull series-resonant converter. The mechanism and frequency characteristics of EMI in the converter are analyzed. On this basis, the cascade EMI filter is proposed to optimize the structure and reduce EMI. To enhance the performance of noise filtering, the CLC filter is proposed as an example of the cascade EMI filter. The insertion loss is studied as the design criteria of CLC filter. The effectiveness of the design is theoretically analyzed and experimentally verified. The proposed EMI filter shows an enhanced performance of electromagnetic compatibility for EV.