一种车用恒流/恒压模式的四开关Buck-Boost变换器控制策略研究  

Study on Control Strategy of a Four-Switch Buck-Boost Converter with CC/CV Modes for Automotive Applications

作　　者：吴东铭 李柯宇 谢泽亚 杨涛[1] 甄少伟[1] 罗萍[1,2] 张波 WU Dongming;LI Keyu;XIE Zeya;YANG Tao;ZHEN Shaowei;LUO Ping;ZHANG Bo(State Key Lab.of Elec.Thin Films and Integr.Dev.,Univ.of Electronic Science and Technology of China,Chengdu610054,P.R.China;Institute of Electronic and Information Engineering of UESTC in Guangdong,Dongguan,Guangdong523808,P.R.China)

机构地区：[1]电子科技大学电子薄膜与集成器件国家重点实验室,成都610054 [2]电子科技大学广东电子信息工程研究院,广东东莞523808

出　　处：《微电子学》2022年第5期790-796,共7页Microelectronics

基　　金：广东省基础与应用基础研究基金资助项目(2021A1515011309)。

摘　　要：对一种车用恒流/恒压模式的四开关Buck-Boost变换器的控制策略进行了研究。在输入输出电压接近时引入Buck-Boost模式,从而在不同输入输出电压大小关系下,通过检测功率管占空比大小,实现Buck模式、Boost模式和Buck-Boost模式之间的平滑切换,提高了系统的稳定性。通过设计最大值选择电路,使变换器在充电应用中自动从恒流模式切换到恒压模式,模式切换平滑稳定。仿真结果表明,在24 V输出电压下,变换器从Buck模式切换到Buck-Boost模式时,输出电压下冲为9.2 mV,变换器从Boost模式切换到Buck-Boost模式时,输出电压下冲为92 mV。变换器在Buck模式与Boost模式下均能实现恒流/恒压模式的自动平滑切换。The control strategy of a four-switch buck-boost converter with constant current/constant voltage modes was studied. When the input and output voltages were close to each other, buck-boost mode was adopted to realize smooth switching between buck mode, boost mode and buck-boost mode by detecting the duty cycle of the power FETs under different relationship between input and output voltages, thus improving the stability of the system. By designing the maximum value selection circuit, the converter could automatically transit from constant current mode to constant voltage mode in charging application, and the mode transition was smooth and stable. The simulation results show that at 24 V output voltage, when the converter switches from buck mode to buck-boost mode, the output under-shoot voltage is 9.2 mV. When the converter switches from boost mode to buck-boost mode, the output under-shoot voltage is 92 mV. The converter can automatically realize smooth conversion between constant current and constant voltage modes in both buck mode and boost mode.

关 键 词：四开关Buck-Boost变换器 PWM 模式切换 恒流/恒压 

分 类 号：TN433[电子电信—微电子学与固体电子学]