开关电感Boost变换器建模与仿真分析

摘要

针对光伏发电系统中传统Boost变换器的升压能力问题，将开关电感结构嵌入传统Boost变换器中，分析变换器功率开关器件的“ON”和“OFF”状态的工作机理，建立升压增益比与开关器件周期占空比之间的关系。利用状态空间平均法建立开关电感Boost变换器的数学模型，并在此模型基础上，对功率开关器件的不同工作频率进行仿真分析。仿真结果表明，开关电感Boost变换器不仅比传统Boost变换器具有更高的升压能力，而且在高开关频率下也能有效减小输出量的纹波，提升变换器的转换效率；同时也验证了模型的合理性和正确性，为工程实践设计提供理论支撑。%Aiming at the boost ability of the traditional boost converter in photovoltaic power generation system , the switched inductor structure is embedded in the traditional boost converter. The working mechanism of the converter is analyzed through the state of ON and OFF about power switch device and the relationship between the ratio of boost gain and the periodic duty of switch device is established. The mathematical model of switched inductor Boost converter is established by state space average method. Based on this model , simulation and analysis for different operating frequency of the power switching device is executed. The simulation results show that switched inductor Boost converter not only can have higher boost ability than the traditional Boost converter , but also can make the ripple of the output decreased effectively in high switching frequency to improve the conversion efficiency of converter. Meanwhile , it also proves the rationality and correctness of the model, and provides theoretical support for engineering design.