一种用于电池储能的T型三电平能量转换系统研究

发布时间：2018-06-04 07:19

本文选题：T型结构 + 三电平　；参考：《东华大学》2014年硕士论文

【摘要】：随着社会经济的发展和工业水平的提高,传统电网高成本,运营难度大,安全可靠性差等弊端越发凸显。分布式发电具有安装简单、污染低、效率高、性能可靠等优点,能够很好地解决传统集中式的大电网所存在的问题。但是太阳能、风能等可再生分布式能源有波动性、间歇性等缺点,分布式能源的大量接入会影响电网的安全和稳定。储能技术的应用在电网和用户间增加了一级能量缓冲,无论是对可再生能源的大量接入,还是微网孤网(孤岛)的稳定运行,都提供了一种有效的方式。电池储能是一种常用的储能方式,具有特性好、储能密度较高、环境条件好、技术成熟、对安装地点无特殊要求等优点,有着巨大的应用前景。用于电池储能的能量转换系统(Power Conversion System, PCS),做为电池与电网的接口,其性能好坏,直接影响电池储能的效率和电网的稳定运行。三电平电路相较于传统的两电平电路,在用于电池储能并网这类高压大容量场合,有着显著的优势。而T型三电平拓扑,相比于传统的NPC三电平拓扑,具有导通损耗小,空间体积小,保护简单等优点,在一定的功率等级和开关频率下,较NPC三电平拓扑有着更高的能量密度和更高的效率。本文研究了一种用于电池储能的T型三电平能量转换系统,主要做了以下几方面工作： (1)对三电平电路和三电平电路的调制策略进行了综述,介绍了T型三电平电路的结构,介绍了其工作原理。对T型三电平电路拓扑的损耗进行了分析,并给出了电路正常工作时功率器件的导通损耗与开关损耗的计算方法。 (2)建立了T型三电平并网变流器的数学模型,对并网变流器的控制策略进行了研究,并给出了变流器的控制结构。对SVPWM调制算法进行了详细研究,介绍了中点电压不平衡产生的机理并提出了解决方法。 (3)搭建了全数字控制的T型三电平并网变流器实验平台,介绍了变流器的主电路组成,对变流器数字控制电路的软硬件设计进行了详细研究和介绍。 (4)在Matlab\Simulink中搭建了T型三电平并网变流器的仿真模型,通过仿真验证了控制算法。在搭建的实验平台上进行了电池充电、放电和充放电切换实验,进一步验证了控制算法。
[Abstract]:With the development of social economy and the improvement of industrial level, the disadvantages of traditional power grid such as high cost, difficult operation, poor safety and reliability are becoming more and more prominent. Distributed generation has the advantages of simple installation, low pollution, high efficiency and reliable performance. It can solve the problems of traditional centralized power grid. However, renewable distributed energy, such as solar energy and wind energy, has some disadvantages, such as volatility, intermittence and so on. A large number of distributed energy sources will affect the security and stability of power grid. The application of energy storage technology increases the first-order energy buffering between the power grid and users. It provides an effective way to access a large number of renewable energy sources, as well as the stable operation of the microgrid isolated network (isolated island). Battery energy storage is a common energy storage method, which has the advantages of good characteristics, high energy storage density, good environmental conditions, mature technology, no special requirements for installation sites, and has a great application prospect. As the interface between battery and power grid, the power Conversion system used for battery energy storage has good or bad performance, which directly affects the efficiency of battery energy storage and the stable operation of power grid. Compared with traditional two-level circuits, three-level circuits have obvious advantages in high-voltage and high-capacity applications such as battery energy storage and grid-connected. Compared with the traditional NPC three-level topology, T-type three-level topology has the advantages of small turn-on loss, small space volume, simple protection and so on. At a certain power level and switching frequency, It has higher energy density and higher efficiency than NPC three-level topology. In this paper, a T type three-level energy conversion system for battery energy storage is studied. The main work is as follows: In this paper, the modulation strategies of three-level circuit and three-level circuit are summarized, the structure of T-type three-level circuit and its working principle are introduced. The topology loss of T type three-level circuit is analyzed, and the calculation method of the on-loss and switching loss of power device is given when the circuit is in normal operation. The mathematical model of T type three-level grid-connected converter is established, the control strategy of grid-connected converter is studied, and the control structure of the converter is given. The SVPWM modulation algorithm is studied in detail. The mechanism of neutral voltage imbalance is introduced and the solution is proposed. The experimental platform of T type three-level grid-connected converter with digital control is built, the main circuit composition of converter is introduced, and the hardware and software design of digital control circuit of converter is studied and introduced in detail. The simulation model of T type three-level grid-connected converter is built in Matlab\ Simulink, and the control algorithm is verified by simulation. The battery charging, discharging and charge-discharge switching experiments are carried out on the platform, which further verifies the control algorithm.
【学位授予单位】：东华大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM46

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