【作者】 李丹；

【导师】 梁晖；

【作者基本信息】 北京交通大学 ， 电气工程（专业学位）， 2018， 硕士

【摘要】 近年来,随着能源短缺与环境污染问题日益突出,电动汽车以其节能、环保的优点受到广泛关注,与此同时,电动汽车退役的动力电池回收与梯次利用成为一个亟待解决的问题。而储能系统对电池的性能要求较低,将退运电池用于储能系统中,可有效解决间歇性分布式能源发电带来的功率波动问题,因此,本文针对传统储能系统存在的问题,结合梯次利用电池对储能变流器进行了详细研究。首先,分析了传统电池成组中存在的不一致性问题,而后结合电力电子领域探讨了柔性成组技术,通过对比多种柔性成组储能变流器的性能,进一步提出了模块化独立控制梯次利用电池储能系统,并阐述其结构与工作方式。鉴于该系统的核心模块为双有源全桥(Dual Active Bridge,DAB)模块,故首先从DAB模块的工作原理及其性能进行分析,以此引申为多模块DC-DC变换器,通过分析其工作原理,推导出各模块之间存在电流耦合关系,并进一步研究了副边电流解耦方式,实现各模块的独立控制。其次,基于多模块DC-DC变换器的工作原理,对梯次利用电池储能变流器的移相控制、电池模块独立控制、系统控制等做了详尽的分析,同时探讨了多种均衡控制方式,针对本储能系统各电池模块的SOC差异,研究了传统型SOC均衡控制策略,并通过公式推导说明该策略的缺陷性,而后提出了基于容量不一致的SOC均衡控制策略。为验证拓扑结构与控制方法的正确性,通过搭建仿真平台并针对各种情况的波形进行分析。最后,从系统、辅助变流器硬件和软件三个层面详细介绍了储能系统的结构与控制,并在硬件平台上完成了多项基本实验,对不同条件下的实验波形进行了分析,通过实验结果进一步验证了电路拓扑及控制策略的可行性。更多还原

【Abstract】 In recent years,with the energy shortage and environmental pollution problems have become increasingly prominent,electric vehicles have been attracting wide attention due to their energy saving and environmental advantages.At the same time,the recovery of power batteries and secondary use for the retirement of electric vehicles have become an urgent problem to be solved.As the requirements of batter performance for energy storage system are relatively lower,those "retired batteries" may be used for energy storage systems,it can effectively solve the problem of power fluctuation caused by intermittent distributed energy generation.Therefore,this thesis aims at addressing the problems of traditional energy storage systems,a detailed study of the energy storage converters using secondary use battery is conducted.First of all,the thesis analyzes the inconsistencies existing in the traditional battery grouping and discusses the advantages and disadvantages of the flexible grouping technology in the power electronics field.By comparing the performance of a variety of flexible-grouped energy storage converters,this thesis proposes a modular topology and independent control strategy of the battery-based energy storage system.The structure and working principle of this system are comprehensively described.Because the core module of the system is a Dual Active Bridge(DAB)module,only the working principle and performance of a DAB module are described and extended to a multi-module DC-DC converter.By analyzing DC-DC converter’s working principle,the current coupling relationship among modules is deduced,and the secondary side current decoupling method is further studied to realize the independent control of each module.Secondly,based on the working principle of multi-module DC-DC converter,the phase shift control,battery module independent control and system control of the energy storage converter using secondary use battery are analyzed in detail.At the same time,the various equilibrium control method is analyzed.The traditional SOC equilibrium control strategy is analyzed under the condition of the difference of SOC in each battery module.The deficiency of the strategy is deduced through the formula,and then this thesis proposes an improved SOC equalization control strategy based on capacity inconsistency.In order to verify the accuracy of the newly proposed system topology and its control strategy,this thesis models the relevant simulation circuit and analyzes the simulation results of various parts of the system under different working conditions.Finally,the structure and control of the energy storage system are introduced in detail from the three levels of system,auxiliary converter hardware and software.In addition,this thesis completes a number of basic experiments on test platform,analyzes the experimental waveforms under different working conditions,and further verifies the feasibility of the circuit topology and control strategy through the experimental results.更多还原