【作者】 杨静；

【导师】 祝龙记；

【作者基本信息】 安徽理工大学 ， 电气工程， 2025， 硕士

【摘要】 随着电动汽车产业的发展,电动汽车充电设备得到了广泛关注和研究。汽车充电桩一般由前级AC/DC变换器与后级DC/DC变换器构成。其中,后级双向DC/DC变换器直接给电动汽车动力电池传送电能,并控制动力电池的充放电流,为汽车充电桩中的关键环节,影响着充电设备的充电性能,特别是在快速响应与精确控制等方面。常规的DC/DC变换器在负载突变时,若响应过程过于剧烈或波动过大,可能导致输出电压的稳定性不足,进而影响充电效率与工作可靠性。因此,本文通过对多种双向DC/DC变换器的性能进行比较,选择CLLC谐振式双向DC/DC变换器应用于汽车充电桩来展开研究。首先,在对CLLC谐振式双向DC/DC变换器的拓扑结构及工作模式分析的基础上,利用基波分析法对变换器进行建模,分析了充电电压增益特性和输入阻抗特性,并探讨了谐振网络参数对变换器性能的影响。在分析充电特性的基础上,以电压增益范围、软开关实现为要求,给定了谐振网络参数选取的限制条件,并据此计算参数值,同时进行仿真验证其有效性。其次,采用扩展描述函数法建立了变换器的小信号数学模型,通过数学解析获得了所需的传递函数,并运用MATLAB中的扫频法对所建模型进行验证分析。同时,为提高CLLC谐振式双向DC/DC变换器的输出电压动态响应及抗干扰能力,在传统线性自抗扰控制的基础上,引入基于滑模控制的自抗扰控制方法,详细说明了滑模自抗扰控制器的整个设计过程,并对其系统稳定性展开深入了分析。借助MATLAB/Simulink仿真平台,对传统线性自抗扰控制和滑模自抗扰控制进行了仿真对比,结果表明滑模自抗扰控制在动态性能与稳态输出方面均展现出更优表现。最后,搭建了CLLC谐振式双向DC/DC变换器的实验样机,并通过实验测试验证控制方法的实际效果,相较于传统线性自抗扰控制方法,本文提出的滑模自抗扰控制方法能够有效地提高系统的动态性能和使输出电压稳定。图[66]表[3]参[84]更多还原

【Abstract】 As the electric vehicle industry develops,electric vehicle charging equipment has received extensive attention and research.The vehicle charging pile comprises a front-stage AC/DC converter and a back-stage DC/DC converter.Among them,the back-stage bidirectional DC/DC converter,as a key link in the vehicle charging pile,directly transmits electric energy to the electric vehicle power battery and controls the charging and discharging flow of the power battery,which influences the charging performance of the charging equipment,especially in the aspects of fast response and precise control.A conventional DC/DC converter will be in a sudden change in load if the response process is too drastic or fluctuations are too large,which may lead to a lack of stability of the output voltage,affecting the charging efficiency and reliability.Therefore,this paper compares the performance of various bidirectional DC/DC converters and selects the CLLC resonant bidirectional DC/DC converter to be used in automobile charging piles to carry out the research.Firstly,based on the topology and operating mode analysis of the CLLC resonant bidirectional DC/DC converter,the converter is modeled using fundamental wave analysis,the charging voltage gain characteristics and input impedance characteristics are analyzed,and the effects of the resonant network parameters on the converter performance are explored.Based on analyzing the charging characteristics,the constraints for selecting the parameters of the resonant network are given in terms of the voltage gain range and soft-switching realization,the parameter values are calculated accordingly,and simulations are conducted to verify their validity.Secondly,the small-signal mathematical model of the converter is established by the extended describing function method,and the required transfer function is obtained by mathematical analysis,and the model is verified and analyzed by using the sweep method in MATLAB.Meanwhile,in order to improve the output voltage dynamic response and anti-interference capability of the CLLC resonant bidirectional DC/DC converter,an active disturbance rejection control method based on sliding mode control is introduced based on the traditional linear active disturbance rejection control;The whole design process of the sliding mode active disturbance rejection controller is explained in detail,and its system stability is analyzed in depth.With the help of the MATLAB/Simulink simulation platform,the comparison experiments between the traditional linear active disturbance rejection control and the sliding mode active disturbance rejection control are carried out,and the results show that the sliding mode active disturbance rejection control shows better performance in terms of dynamic performance and steady-state output.Finally,an experimental prototype of a CLLC resonant bidirectional DC/DC converter is built,and the practical effect of the control method is verified through experiments.Compared with the traditional linear active disturbance rejection control method,the sliding mode active disturbance rejection control method proposed in this paper can effectively improve the dynamic performance of the system and make the output voltage stable.Figure[66]Table[3]Reference[84]更多还原