阻抗匹配机理及Z阻抗网络变换器构造

发布时间：2018-04-04 21:08

本文选题：变换器　切入点：阻抗匹配　出处：《华南理工大学》2014年博士论文

【摘要】：通过对电力电子变换器的控制，电力电子技术可实现电能不同形式的转换，为此电力电子变换器成为电力电子技术的关键，构造高性能的电力电子变换器始终是电力电子技术最基础的研究工作。本文从阻抗匹配角度研究了阻抗网络对变换器性能的影响，分析了电力电子变换器的阻抗网络匹配机理，形成一种阻抗型变换器的系统设计方法，由此构造出4种新型的Z阻抗网络变换器拓扑。本文所完成的工作具体体现在以下几个方面： (1)根据阻抗网络理论，分析传统电压源和电流源逆变器存在的问题，进而剖析阻抗网络对基本Z源变换器、准Z源变换器、耦合型Z源变换器和电源内嵌型Z源变换器工作性能的影响，为此更加深入认识以Z源变换器为代表的阻抗型变换器构造机理。 (2)首次提出了输入阻抗匹配、输出阻抗匹配、负载相位匹配的电力电子变换器阻抗网络匹配机理。基于该机理，可以通过阻抗网络参数的设计，匹配变换器的工作性能，提高和改变变换器输出特性，由此形成了一种阻抗型变换器的系统设计方法，促进了阻抗型变换器的发展。 (3)根据阻抗匹配变换器的设计方法，构造了两种新型的3-Z阻抗网络DC-DC升压变换器，它们利用多个相同Z阻抗网络串联匹配的方式，使得输出阻抗呈现负阻抗特性，进而大幅度提高了变换器的升压比，理论上可达到350倍，解决了光伏电池输出低电压需升压的问题。 (4)构造了一种新型的Z阻抗网络半桥变换器，该变换器巧妙地将阻抗网络嵌入到半桥变换器中，等效提高了输入阻抗，有效稳定了半桥变换器输入电容的中点电压，解决了电化学电源宽负载范围工作的苛刻要求。 (5)构造了一种新型的双输出Z阻抗网络半桥变换器，该变换器利用两个阻抗网络并联匹配的设计，等效降低了输出阻抗，减少了四分之一的开关元件和电容，实现了双负载输出的要求，，有效降低了电动汽车驱动电源成本，同时提高了它的功率密度。论文的创新之处在于从一个新的视角，深入剖析了以Z源变换器为代表的阻抗型变换器的构造机理，提出了一种具有一般意义的阻抗型变换器的构造方法，推动了电力电子变换器设计的系统化，具有明显的理论和实际应用价值。
[Abstract]:Through the control of power electronic converter, power electronic technology can realize different forms of power conversion, so power electronic converter becomes the key of power electronics technology.The construction of high performance power electronic converters is always the most basic research work of power electronics technology.In this paper, the influence of impedance network on converter performance is studied from the angle of impedance matching, and the impedance network matching mechanism of power electronic converter is analyzed, and a system design method of impedance converter is formed.Therefore, four new Z-impedance network converters are constructed.The work accomplished in this paper is embodied in the following aspects:1) according to the theory of impedance network, the problems of traditional voltage source and current source inverter are analyzed, and the impedance network is applied to the basic Z-source converter and quasi-Z-source converter.Because of the influence of the performance of the coupled Z-source converter and the power source embedded Z-source converter, the construction mechanism of the impedance converter represented by the Z-source converter is more deeply understood.(2) the impedance network matching mechanism of power electronic converter with input impedance matching, output impedance matching and load phase matching is proposed for the first time.Based on this mechanism, the system design method of impedance converter can be formed by designing the parameters of impedance network and matching the working performance of the converter to improve and change the output characteristics of the converter.It promotes the development of impedance converter.According to the design method of impedance matching converter, two novel 3-Z impedance network DC-DC boost converters are constructed. They make use of several series matching modes of the same Z impedance network to make the output impedance show negative impedance characteristics.Furthermore, the boost ratio of the converter is greatly improved, which can reach 350 times theoretically, which solves the problem that the low output voltage of the photovoltaic cell needs to be raised.In this paper, a novel Z-impedance half-bridge converter is constructed, in which the impedance network is embedded into the half-bridge converter, and the input impedance is increased, and the midpoint voltage of the input capacitance of the half-bridge converter is effectively stabilized.The demanding requirement of wide load range of electrochemical power supply is solved.A novel half bridge converter with double output Z impedance network is constructed. The design of this converter is based on the parallel matching of two impedance networks, which reduces the output impedance, reduces the switch element and capacitance by 1/4.The requirement of double load output is realized, and the cost of electric vehicle driving power is reduced effectively, and its power density is improved.The innovation of this paper lies in the deep analysis of the construction mechanism of the impedance converter represented by the Z-source converter from a new angle of view, and a general construction method of the impedance converter is proposed.It promotes the systematization of power electronic converter design and has obvious theoretical and practical application value.
【学位授予单位】：华南理工大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TM46

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