基于广义状态空间平均的全桥LLC谐振变换器建模及应用  

Modeling and application of full-bridge LLC resonant converter based on generalized state space averaging method

作　　者：李玉东[1,2] 史澳 Li Yudong;Shi Ao(School of Electrical Engineering and Automation,Henan Polytechnic University,Jiaozuo 454003,China;Key Laboratory of Intelligent Detection and Control of Coal Mine Equipment,Henan Province,Jiaozuo 454003,China)

机构地区：[1]河南理工大学电气工程与自动化学院,焦作454003 [2]河南省煤矿装备智能检测与控制重点实验室,焦作454003

出　　处：《国外电子测量技术》2024年第10期160-168,共9页Foreign Electronic Measurement Technology

基　　金：国家自然科学基金(61703144);河南省科技攻关项目(222102220034)资助。

摘　　要：LLC谐振变换器在设计新的控制策略时,传统的设计流程需要手动拟合调试出控制参数,闭环稳定性分析涉及高阶函数计算。为了简化传统设计流程,引入广义状态空间平均(GSSA)理论对全桥LLC谐振变换器进行建模,将传统的阻抗物理模型转化为数学模型,推导出GSSA闭环大信号和小信号模型。通过GSSA模型推导系统传递函数矩阵并分析全桥LLC谐振变换器的动态特性,设计闭环PI控制参数,最后使用特征值分析法判断闭环系统稳定性。GSSA理论和模型结合MATLAB仿真,直接解决高阶函数的计算,快速推导控制参数,简化了设计新控制策略需要的调参环节和稳定性分析环节。为验证建模的正确性,依据建模推导元件参数搭建了400 W全桥LLC谐振变换器样机。在空载和满载两种工况下进行了实验,实验结果表明,系统响应速度快,与设定的输出参数相符合,输出电压纹波小于1%、最大误差0.4 V。仿真结果和样机实验结果验证了基于GSSA的LLC谐振变换器模型的有效性。When a new control strategy for LLC resonant converter will be designed,the traditional designing process requires manual setting and adjusting control parameters,and the closed-loop stability analysis involves the calculation of higher-order functions.In order to simplify the traditional designing process,this paper introduces the generalized state space averaging(GSSA)theory to model the LLC resonant converter system.The traditional impedance physical model is transformed into a mathematical model,and the GSSA closed-loop large-signal and small-signal models are derived.The transfer function matrix of the system is derived by GSSA model and the dynamic characteristics of the full-bridge LLC resonant converter are analyzed.The closed-loop PI control parameters are designed.Finally,the stability of the closed-loop system is judged by eigenvalue analysis method.GSSA theory and model combined with MATLAB simulation can directly solve the calculation of higher-order functions,quickly derive control parameters,and simplify the parameters adjustment and stability analysis in designing new control strategies.In order to verify the correctness of the modeling,a prototype of a 400 W full-bridge LLC resonant converter is built according to the parameters of the modeling derivation elements.Experiments are carried out under both no-load and full-load conditions.The experimental results show that the system responds quickly,which is consistent with the set output parameters,and the output voltage ripple is less than 1%and the maximum error is 0.4 V.The results of simulation and prototype experimental results demonstrate the effectiveness of the LLC resonant converter model based on GSSA.

关 键 词：全桥LLC谐振变换器 广义状态空间平均 小信号模型 动态特性 稳定性分析 

分 类 号：TN86[电子电信—信息与通信工程]