隔离型双向全桥DC-DC变换器研究

发布时间：2019-03-18 20:27

【摘要】：随着不可再生能源的消耗,以及这类传统能源如石油等对环境造成的危害,可再生新能源的开发与利用在近几年步入了快速发展期,而基于可再生能源与储能元件构成的直流微电网系统也得到了广泛的应用。这其中,电动汽车(Electric Vehicle, EV)因其高效的能源利用率等优势成为我国能源发展战略的重要内容。电动汽车与电网的互动,既有大规模接入并网带来的挑战,又有作为分布式储能元件为电网削峰填谷等起到正面的作用。因此,研究作为电网与电动汽车之间的电力电子接口装置——隔离型双向全桥DC-DC变换器(Isolated Bidirectional full-bridge DC-DC converter, IBDC),对实现电网与电动汽车之间的良好互动具有重要意义。针对隔离型双向全桥DC-DC变换器的特点,本文对单移相控制(Single-phase-shift control, SPS)、双重移相控制(Dual-phase-shift control, DPS)和三重移相控制(Triple-phase-shift control, TPS)理论进行研究,并提出统一的数学模型。通过对三种控制方式控制原理的分析,把每种控制方式下变换器的工作模式分阶段进行介绍。然后根据工作原理和模式,进行公式推导,建立了稳态数学模型。之后对三种控制方式下变换器主要的功率特性进行分析,分别给出了传输功率调节范围,明确三重移相控制的传输功率调节范围是三种控制方式中最大的,具有较好的灵活性。而考虑到单移相控制方式下变换器固有的功率回流现象,会增加开关器件、磁性元件的损耗,从而降低系统整体的效率,本文在每种控制方式的分析中给出了回流功率的表达式,得到了电压传输比与移相比之间的关系,并明确双重移相和三重移相控制能够有效地消除回流功率。同时,对比了三重移相和双重移相控制,前者在减小电流峰值、电流有效值、无功功率的效果上要优于后者。本文通过Matlab/Simulink平台搭建了模型,对三种控制方式都进行了仿真验证。最后,本文还搭建了一台试验性的原理样机。给出了实验装置的参数,并根据参数进行开关器件选型、高频变压器设计。详细介绍了原边侧全桥主电路板、副边侧全桥和驱动电路板的设计,并基于TMS320F28335平台进行带死区的移相程序编程,对控制程序进行介绍。完成三种控制方式下样机的初步试验,并得到每种控制方式的效率,验证了理论分析的准确性。
[Abstract]:With the consumption of non-renewable energy and the harm to the environment caused by this kind of traditional energy such as petroleum, the development and utilization of renewable new energy has entered a period of rapid development in recent years. DC microgrid system based on renewable energy and energy storage elements has also been widely used. Among them, electric vehicle (Electric Vehicle, EV) has become an important part of China's energy development strategy because of its high energy efficiency and other advantages. The interaction between electric vehicles and power grid not only brings the challenge of large-scale access to the grid, but also plays a positive role as a distributed energy storage component for peak-cutting and filling the valley of the power grid. Therefore, as a power electronic interface device between power grid and electric vehicle, the isolated bi-directional full-bridge DC-DC converter (Isolated Bidirectional full-bridge DC-DC converter, IBDC), is studied. It is of great significance to realize the good interaction between power grid and electric vehicle. In view of the characteristics of isolated bi-directional full-bridge DC-DC converter, this paper deals with single phase shift control (Single-phase-shift control, SPS), dual phase shift control (Dual-phase-shift control, DPS) and triple phase shift control (Triple-phase-shift control,). TPS) theory is studied and a unified mathematical model is proposed. Based on the analysis of the control principle of three control modes, the working mode of the converter under each control mode is introduced in stages. Then according to the working principle and mode, the formula is deduced and the steady-state mathematical model is established. Then the main power characteristics of the converter under three control modes are analyzed and the range of transmission power regulation is given respectively. It is clear that the transmission power regulation range of triple phase shift control is the largest of the three control modes and has better flexibility. Considering the inherent power reflux phenomenon of the converter in single phase shift control mode, the loss of switching devices and magnetic components will be increased, thus reducing the efficiency of the system as a whole. In this paper, the expression of reflux power is given in the analysis of each control mode, and the relation between voltage transfer ratio and shift ratio is obtained. It is clear that the double phase shift and triple phase shift control can effectively eliminate the reflux power. At the same time, triple phase shift control is compared with double phase shift control. The former is superior to the latter in reducing current peak value, current effective value and reactive power. In this paper, the Matlab/Simulink platform is used to build the model, and the three control methods are simulated and verified. Finally, an experimental prototype of the principle is built in this paper. The parameters of the experimental device are given. According to the parameters, the switch device is selected and the high frequency transformer is designed. The design of the main circuit board, the auxiliary side bridge and the driving circuit board of the original side full bridge are introduced in detail. The phase shift program with dead zone is programmed based on TMS320F28335 platform, and the control program is introduced. The preliminary tests of the prototype under three control modes are completed and the efficiency of each control mode is obtained. The accuracy of the theoretical analysis is verified.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TM46

【相似文献】