摘要
为提高非隔离型DC-DC变换器的电压增益,减少开关管的电压应力,该文分析了变换器的工作原理,将耦合电感倍压支路引入基础Sepic变换器,并将单开关管替换为具有更低电压应力的双开关管单元,得到一种耦合电感双开关高增益Sepic变换器,其中,两个开关管采用同步导通控制。该变换器可通过调节占空比和匝比调节输出电压,并利用磁集成技术将变换器中的磁性器件进行解耦集成设计,通过有限元电磁场验证了集成方案的可行性,减小了变换器中磁件的体积与数量,提高了变换器的功率密度,给出各项参数的设计方案。最后通过搭建一台额定功率为200 W的实验样机,验证了理论分析的正确性。
In recent years,high-gain DC-DC converters have been widely applied in renewable energy systems,industrial and information equipment,electric vehicles,and charging infrastructure.However,traditional high-gain coupled-inductor DC-DC converters suffer from limitations such as low voltage gain,which necessitates increasing the duty cycle or transformer turns ratio to achieve higher output voltage.It leads to increased losses in switches and diodes,reduced efficiency,and issues like larger transformer volume and leakage inductance,ultimately degrading converter performance.Consequently,research on DC-DC converters with high voltage gain,high power density,and high efficiency has become a focal point.This paper proposes a magnetic-integrated coupled-inductor dual-switch high-gain combined switched-capacitor Sepic converter based on the traditional Sepic topology.The voltage gain is enhanced by integrating coupled inductor voltage-doubling technology with switched capacitor voltage-doubling technology at the rear stage.At the same time,a dual-switch unit is introduced at the front stage to reduce voltage stress on the switches.Magnetic integration is applied to the inductive components.The working principles of the proposed converter are analyzed,key performance parameters are derived,and methods for calculating losses and efficiency are provided.The rationality of the magnetic integration design is verified through magnetic simulation.Finally,an experimental prototype is constructed,and test waveforms are measured.The proposed converter operates with an input voltage of 24 V,a transformer turns ratio of 1,and a duty cycle of 0.25,achieving an output voltage of 216 V and an output power of 200 W.By adjusting the load,the output power can be varied.Theoretical efficiencies at output powers of 160 W,180 W,200 W,220 W,240 W,and 260 W are 91.9%,92.4%,92.7%,92.9%,92.8%,and 92.1%,respectively.Under a 200 W load,the experimental efficiency reaches 92.4%.To improve the performance of traditional high-gain DC-DC converters,this paper proposes a magnetic-integrated coupled-inductor dual-switch high-gain combined switched-capacitor Sepic converter.The converter exhibits the following features:(1)The converter can achieve a high voltage gain even at a low-duty cycle and a small turn ratio.When the duty cycle is 0.25 and the turn ratio is 1,the output voltage is 9 times the input voltage.(2)A diode-capacitor branch absorbs voltage spikes caused by leakage inductance,improving the converter's efficiency and limiting the voltage stress on the switches to approximately 23%of the output voltage.(3)By integrating discrete inductors with coupled inductors through magnetic integration technology,the number and volume of magnetic components are reduced,thereby significantly enhancing the overall power density of the converter.
作者
李洪珠
迟成奥
郭亚涛
李洪亮
Li Hongzhu;Chi Chengao;Guo Yatao;Li Hongliang(School of Electrical and Control Engineering Liaoning Technical University,Huludao 125105 China;Schooling of Mining and Coal Inner Monggolia University of Science and Technology,Baotou 014010 China)
出处
《电工技术学报》
北大核心
2025年第24期8025-8038,共14页
Transactions of China Electrotechnical Society
基金
辽宁省教育厅基本科研面上项目(LJZK0326)
内蒙古自治区高等学校科学研究重点项目(NJZZ22444)资助。
关键词
解耦磁集成
高电压增益
SEPIC变换器
耦合电感
Decoupled magnetic integration
high voltage gain
Sepic converter
coupled inductor
