采用级联Buck调压的元胞化RDCX的低频开关动作使DCX元胞母线低频跳动，并经过层间寄生电容传导低频开关共模噪声。添加屏蔽层虽然可以在一定程度上抑制共模噪声，但会增加损耗。本工作基于静点构造原理，采用单母线多电平电路如飞跨电容电路进行调压，彻底消除调压电路低频开关噪声源的变压器传导路径，抑制元胞化RDCX低频开关共模噪声，相比于屏蔽方法，不改变绕组结构，不牺牲效率；此外，MHz DCX采用反相控制，构造元胞间噪声抵消结构，抑制元胞化RDCX高频开关共模噪声。

The low frequency switching in cellular RDCX with cascaded buck regulator will introduce low frequency CM noise through inter-winding capacitance of the transformer because of the low frequency pulse of the bus in DCX cells. Shielding layer can be inserted to block the CM current, but would also introduce additional loss. The multi-level converter with single input such as flying capacitor converter is adopted as regulator based on static-point construction method. The inter-winding capacitance for noise conduction is eliminated and the low frequency CM noise is suppressed in cellular RDCX. There is no change in winding structure and no sacrifice in efficiency compared with shielding technique. Besides, the inverted-phase control is implemented in DCX to cancel the CM noise in each DCX cell and the high frequency switching CM noise is suppressed in cellular RDCX.

• 250-450V_o，适用于车载充电机后级DC-DC
• 共模噪声下降60dB
• 满载峰值效率约98%，功率密度（含滤波器）800W/in³ @2.3kW

• 250-450V_o for DC-DC stage in OBC
• 60dB CM noise reduction
• ~98% efficiency & 800W/in³ power density (with filter) @2.3kW

Fig. 1 Topology of cellular RDCX with flying capacitor converter as regulator

Fig. 2 Prototype

Fig. 3 Comparison of the measured CM noise

Fig. 4 Comparison of the CM Filter

Fig. 5 Comparison of the total volume