Modeling and design of a fully LCL-EMI fully integrated filter for grid-connected inverters based on planar magnetic integrated technology

This paper presents a fully integrated LCL-EMI filter based on planar magnetic technology. The filter effectively reduces the harmonics and EMI noise generated by inverters using broadband semiconductor devices such as GaN, as well as the overall size, weight, and power density of the system. By analyzing the structure of LCL filter and EMI filter, the filter inductance of LCL filter and the common mode inductance of EMI filter are integrated into an E-type magnetic core, which not only reduces the number of components, but also improves the power density of the system and reduces the cost. Through the analysis of common-mode and differential-mode magnetic circuits, the parameters of each component of the magnetic integrated filter are obtained, and the power loss of the magnetic integrated filter is analyzed. Finally, the correctness and feasibility of the proposed magnetic integration scheme are verified by finite element simulation.