双频DC-DC变换器的磁集成技术OA北大核心CSTPCD

Miniaturization and high power density are the development trends in modern power electronic converters.However,the increase in high frequency inevitably leads to intensified switching losses,reduced converter efficiency,and increased electromagnetic interference.These factors,to some extent,limit the improvement of converter performance.In response to these challenges,various methods have been proposed to address the conflicting relationship between high frequency and efficiency.Soft switching technology,converter parallel technology,and double frequency converters have been utilized in power electronic converters to enhance system performance.Although these methods contribute to improvement,most of them involve the converter's magnetic components,leading to larger converter sizes and related environmental issues.To address these issues,this paper proposes a three-section winding integrated magnetic(TSWIM)technique based on a double frequency DC-DC converter.This technique decouples and integrates the magnetic components within one core of the converter.Through theoretical analysis,simulation,and experimental validation,it is demonstrated that this integration method achieves a uniformly distributed magnetic flux density within the magnetic core.Consequently,it reduces the volume and weight of the converter,while improving the power density of the system. Firstly,this paper establishes an equivalent magnetic circuit model for the TSWIM and deduces the decoupling condition by mitigating the coupling effect between each winding.To select a suitable core model,careful consideration is given to the magnetic saturation problem and window area dimensions.Mathematically deriving the maximum magnetic flux density generated by each magnetic column of the core from the TSWIM helps determine if the core's saturation magnetic flux density is reached.Finally,the number of turns in the integrated winding and the calculation method of the air gap are elaborated upon. Secondly,the working principle of the double frequency DC-DC converter under the integration is analyzed,and by constructing the gyrator-capacitor model of the TSWIM,the co-simulation method is utilized to verify that the integration method can enable the converter to operate normally.Then,the TSWIM is subjected to finite element simulation with the existing integration method(IM),and the results show that the TSWIM has a more uniform flux density distribution,smaller flux density,and smaller magnetic loss by comparing the flux density and magnetic core loss of the two. Finally,a 48 V/12 V,108 W experimental prototype was constructed to validate the TSWIM and compare it with the separated magnetic part(SM)as well as the IM.Based on the experimental findings,it can be concluded that both the IM and the TSWIM demonstrate a relatively similar response speed,approximately 2.85 ms,with respect to output voltage and dynamic response of high-frequency inductor current.In terms of low-frequency inductor current,the TSWIM and the SM mirror the fluctuations in high-frequency inductor current,exhibiting a response speed of around 3.2 ms.Consequently,the TSWIM and the SM remain nearly synchronized.Conversely,the IM exhibit a comparatively slower dynamic response speed.From the efficiency comparison,the efficiency of the TSWIM is closer to that of the SM,and the volume and weight are reduced by 31.2％and 25.3％compared with the SM,which improves the power density of the system,and the experiments and simulations verify the correctness of the theoretical analysis.