A full planar emi filter integrated structure composed of circular planar pcb coupled inductors

Abstract

The invention provides a whole-plane EMI filter integrated structure composed of round-plane PCB coupling inductors. The whole-plane EMI filter integrated structure comprises the round-plane PCB coupling inductors, a common mode inductor, a differential mode inductor, a differential mode capacitor I, a differential mode capacitor II, a common mode integrated LC unit I and a common mode integrated LC unit II, wherein leakage inductors of the round-plane PCB coupling inductors serve as the common mode inductor, the differential mode inductor, the differential mode capacitor I and the differential mode capacitor II respectively, one port of the differential mode capacitor I serves as the input end of a filter, and one port of the differential mode capacitor II serves as the output end of the filter. According to the whole-plane EMI filter integrated structure, the round-plane PCB coupling inductors are adopted as basic constituting units of the plane EMI filter, the coupling inductors of novel structures use a PCB as a substrate, round ceramic plane magnetic cores are embedded into the substrate, PCB printing conductive wires serve as primary and secondary windings of the magnetic cores, and the primary and secondary windings are wound around the magnetic cores through metal through holes. The coupling inductors of the novel structures omit pot-shaped magnetic cores which are large in size and sealed in the filter, decoupling of constituting modules of the filter is achieved, cooling is facilitated, the size and weight of the plane EMI filter are effectively reduced, and connection of the modules of the filter is simple.

Description

Technical field: [0001] The invention relates to a full-plane magnetic integration structure of an EMI filter, in particular to a plane EMI filter integration structure composed of a circular plane PCB coupling inductor. Background technique: [0002] With the continuous advancement of science and technology, electronic components continue to be miniaturized and integrated, which makes the composition of power electronic conversion devices more flexible. However, since more components are concentrated in a small space, the distribution density is too high, and the probability of generating and suffering electromagnetic interference is greatly increased. At the same time, the du / dt and di / dt of power electronic devices working in the switching state are relatively large, and the surge current and peak voltage generated by them become interference sources, making the switching voltage and current rich in high-order harmonics. In order to ensure the safe and reliable operation...

AI Technical Summary

Problems solved by technology

The EI core is replaced by a pot-shaped magnetic core. The helical coils are all contained in the magnetic core, and the utilization rate of the conductor is improved. The existence of the common mode inductance layer increases the inductance value. The planar integrated LC structure adopts a circular planar helical coil. , which eliminates the influence of uneven current distribution at the corner of the rectangular spiral coil at high frequencies, increases the insertion loss of the filter, and improves the high-frequency performance of the filter, but the use of the pot-shaped magnetic core makes the volume of the filter The increase does not conform to the development trend of filter miniaturization. Moreover, each module is enclosed in the magnetic core, which brings difficulties to the installation and connection of each module, and is not conducive to heat dissipation, which affects the reliability of the filter when it is working.

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