【作者】 王磊；

【导师】 郑诗程； 郎佳红；

【作者基本信息】 安徽工业大学 ， 电气工程， 2023， 硕士

【摘要】 在“碳达峰”和“碳中和”国家战略的引领之下,新能源发电技术步入高速发展的时代,光伏发电等新能源发电逐渐向分布式发电技术发展,成为目前新能源发电的主要方式。然而,分布式光伏发电系统中的太阳能电池电压相对较低,通常需要使用高增益DC/DC变换器把电压提升至并网发电所需要的电压值,以实现系统经济、高效、可靠运行。因此,研究高效可靠的高增益DC/DC变换器拓扑结构,提高可再生能源发电并网效率具有十分重要的学术意义和实用价值。本文首先以Boost变换器与Sepic变换器为基础,从结构上进行优化级联并嵌入双MOS管结构,提出了一种基于双管结构的二次型Boost-Sepic变换器拓扑结构。该变换器通过多种升压手段相互叠加的方式提高了输出电压,以Boost电路和Sepic电路共用开关管的形式简化了拓扑构造,同时还引入了双管结构分担了电压应力。为了进一步提高电压增益,降低器件的电压应力,在上述变换器的基础上采用交错并联的方式代替双MOS管结构,并引入耦合电感技术,提出一种基于耦合电感的两相交错型高增益DC/DC变换器拓扑结构。该变换器拥有反向对称的Boost-Sepic结构和以耦合电感为升压手段的倍压单元,通过控制A、B两相交错运行,升压单元可持续向后续电路传递能量。在实现超高电压增益的同时,两相交错结构避免了开关管和二极管电压应力的逐级递升,抑制了输入电流纹波,而且完全对称的结构为变换器的控制提供了方便。本文详细分析了所提两种变换器的升压原理和器件的工作特性,并通过Matlab/Simulink进行了初步仿真验证。之后,为了研究变换器系统的动态响应性能,对变换器拓扑进行了建模分析并设计了补偿控制器。最后,基于DSP28335分别搭建了200W和400W的原型样机,验证了理论分析的正确性。更多还原

【Abstract】 Under the guidance of the national strategy of "carbon peaking" and "carbon neutrality",new energy power generation technology has entered an era of rapid development,and new energy power generation such as photovoltaic power generation has gradually developed into distributed generation technology,becoming the main way of new energy power generation.However,the solar cell voltage in distributed photovoltaic power generation systems is relatively low,and it is often necessary to use a high-gain DC/DC converter to increase the voltage to the voltage value required for grid-connected power generation to achieve economical,efficient and reliable operation of the system.Therefore,it is of great academic significance and practical value to study the topology of efficient and reliable high-gain DC/DC converters to improve the grid-connected efficiency of renewable energy generation.Based on the Boost converter and the Sepic converter,this paper first optimizes the cascade of the two converters and embeds the double MOS tube structure to propose a quadratic Boost-Sepic converter topology based on the double tube structure.In the proposed converter,the output voltage is increased by superimposing multiple boost methods,simplifying the topology in the form of a switch tube shared by the Boost circuit and the Sepic circuit,while also introducing a two-tube structure to share the voltage stress.For the sake of raising voltage gain and narrowing voltage stress of device,the two-MOS-tube structure is replaced by the interleaved parallel connection method on the basis of the above converter.In this way can we put forward a twophases interlaced ultra-high gain DC/DC converter topology which based on coupled inductance.The converter has a reverse-symmetrical Boost-Epic structure and a voltage doubling unit with coupled inductance as the boost method,and the boost unit can continuously transfer energy to the subsequent circuit by controlling the staggered operation of the two phases A and B.The two-phase interleave structure can avoid the voltage stress of the diode and the switch from step to step,and suppress the input current ripple.While achieving ultra-high voltage gain,the complete symmetry structure provides convenience for the control of the converter.This article is the elaboration of the boost principle and device operating characteristics of the two proposed converters.In addition,Preliminary simulation verification was conducted using Matlab/Simulink.Then,The compensation controller is designed for the sake of studing the dynamic performance of the converter system.Finally,200 W and 400 W prototypes are built based on DSP28335,which verifies the correctness of the theoretical analysis.更多还原