【作者】 胡国珍；

【导师】 段善旭；

【作者基本信息】 华中科技大学 ， 电气工程， 2012， 博士

【摘要】 为有效应对能源和环境挑战,实现汽车产业可持续发展,发展电动汽车已成为全球汽车工业应对能源和环境问题的共同选择。近年来随着电动汽车相关关键技术的攻克,加快推进了电动汽车产业化进程,与电动汽车高速发展相配套的能源供给设施的建设是产业化推广的基础,也迎来了快速发展时期。充放储一体化电站是目前新兴的多功能智能电站,可完成动力电池能量注入、向电网回馈能量、接受电网调度、经济化运行等功能。一体化电站的建设和运营有效实现了电站与智能电网的有效融合,是未来电动汽车电站运营的有效模式。本文针对充放储一体化电站中的储能电池能量变换与控制技术的基本机理和设计方法进行了探讨,主要研究了电池充电系统、放电系统、储能容量配置等方面的关键问题。目前电动汽车主要采用锂离子动力电池作为能量供给单元,锂离子电池工作特性决定了其在使用过程中必须保证既不能欠充也不能过充,因此好的容量注入技术是电池充电过程中必须解决的问题。本文在分析锂离子电池特性的基础上,通过实验数据拟合出了电池模型相关参数,建立了锂离子电池模型；结合电池精确模型,设计了适合充电应用的恒压恒流控制策略,并在以移相全桥拓扑为原型的充电装置上进行了验证。由于电动汽车的电池标准不统一,不同厂家生产的电池电压和电流等级不尽相同,因此在设计充电装置时,其输出电压、输出电流以及功率等级存在不确定因素。为满足充电应用需求,构建了新型串并混联组合充电系统结构。本文研究了基于受控源等效的多模块建模方法,在此基础上,完成了串并混联组合系统功率均分控制器的设计,并通过搭建一套串并组合充电系统进行了实验验证；结合系统结构和充电应用模态,进一步分析了电压源并联和电流源串联的系统稳定运行特性及其相关要素。充放储一体化电站的建设中,可充分发挥电池储能的作用,利用动力电池组在晚间低谷时段充电,白天高峰时段向电网并网送电,有效提高电池寿命及商业价值。并网放电装置作为储能动力电池与电网之间的功率控制环节,满足储能电池向电网进行能量回馈的应用需求。本文研究了弱电网下并网放电装置的并网电流控制技术,重点关注其入网电流谐波畸变问题。首先分析了两级式并网放电装置结构和协调控制机理,给出了直流母线外环设计原则；然后分析了弱电网下LC并网控制器缺陷,基于电网阻抗检测,提出了一种自适应PIR控制策略：相对与LC并网方式,LCL并网方式具有较好的高频抑制能力,但其谐振容易使并网电流波形质量变差,严重时将导致系统不稳定；提出了一种基于谐波补偿的LCL并网有源阻尼方法,通过提取并网谐波电流补偿到控制系统补偿了谐振频率附近谐波对系统的影响,提高了并网电流电能质量,该方法的引入减少了传统有源阻尼使用的传感器数量,节约了系统成本。充放储一体化电站中,多组电池通过多台并网放电装置集中向电网回馈能量,从而构成了电站能量回馈系统。实际应用中电网阻抗的存在给多台并网放电装置接入电网带来较大影响。本文主要关注多逆变器并网系统建模和稳定运行特性。基于电路网络理论建立多机并网系统等效模型,推导出了LC和LCL两种并网方式下的逆变器输出阻抗模型,分析了阻抗模型特征；应用电流源并网的改进型阻抗比判据,分析了LC和LCL并网方式下稳定运行特性。为提高电站内部供电可靠性和运营经济性,国内外一些电动汽车充电站在建设时开始考虑新能源的利用。本文采用负荷缺电率和单位运行成本为指标研究了光伏发电单元接入充放储一体化电站容量配置。选用全钒液流电池和铅酸蓄电池作为电站储能单元,基于电化学特性和运行成本差异,对比分析了两种电池应用于一体化电站供电系统中的容量配置问题。全钒液流电池因其优越的电池特性,大规模接入时具有较好的经济性。更多还原

【Abstract】 To deal with energy and environmental challenges effectively and achieve the sustainability of automobile industry, the development of EV (Electric Vehicles) has become a common choice for global automotive industry in recent years. Construction of energy supply facilities is the basis of promotion of the EV, which also ushered in a period of rapid development with the industrialization of EV. Integrated EV power plant of charge, discharge and storage is a kind of multi-function smart power plants, which can complete these functions, such as battery energy injection, feedback energy to grid, accepting power dispatching from grid, economy operation. The construction and operation of integrated EV power plant can realize the integration of power station and smart grid effectively. And it will be the suitable mode of EV power plant in future. In this paper, basic theory, design methods and control technique of power conversion system in the EV power plant are studied and discussed. And some key issues are focus about charging and discharging system.Lithium-ion batteries are usually used to store energy in the EV. Operating characteristics of lithium-ion battery determine that it can not overcharge and overdischarge. Good capacity injection technology is the key to charge the battery. Considering the characteristics of lithium-ion battery, a constant current and constant voltage charging control strategy was presented in this paper A 3-kW charging device was designed and verified the proposed strategy, which adopted phase-shifted full-bridge topology.Nowadays the battery standards of EV are not uniform and the batteries of different manufacturers have different voltage or current rating. To meet the different voltage or current level of battery charging requirements, modular structure can be adopted. A hybrid combination structure of charging system was proposed in this paper. For the convenience to analyze the combination system, this paper presented a kind of modelling method based on equivalent controlled source model. And the nature of power sharing of the combination system was described. Finally, power sharing controller was designed and verified at a set of charging experiment system. Further study about stability of the voltage source in parallel and current source in series was presented.The battery packs of integrated EV power plant can be charged at off-peak hours in the evening and discharged at peak hours during the day, which improved battery life and commercial value. Grid-connected discharging devices, which used as a power control uint between storage battery and grid, can meet the need of energy feedback to the grid. This paper studied control technology of the discharge device in weak grid, and focued on its current THD (Total Harmonic Distortion). Two-stage topology of discharge device and its coordination mechanism were introduced. Then the defects of LC grid-connected mode were presented and an adaptive PIR control strategy was proposed based on grid impedance detection. Due to the resonance phenomenon of LCL filter which could affect the grid-connected current quality of electric energy, a harmonic compensation active damping method was proposed. The method introduced can reduce the number of sensor, save system cost and decrease unreliable factors caused by the excessive introduction of sensors.Among the integrated EV power plant, multiple sets of discharge devices consist of energy feedback system. The interaction of multi-inverters system poses some problems. This paper focuses on the modeling and stable operating characteristics of multi-inverter grid-connected system. Equivalent model of multi-inverter grid-connected system was deduced based on circuit network theory. And the output impedance model and its characteristics of LC and LCL grid-connected inverter were presented. A current source impedance ratio criterion was proposed, and then stability was analyzed based on the criterion.In order to improve power supply reliability and operating economics of the power plant, the utilization of renewable energy was considered by some domestic and international EV charging station. In this paper, LPSP (Loss of Power Supply Probability) and LCE (Levelied Cost of Energy) was adopted as evaluation indicator to analysis system capacity configuration. Vanadium redox flow battery and lead-acid battery were selected as energy storage unit of the EV power plant. Based on the difference of electrochemical characteristics and operating costs, the comparative analysis of these two batteries among capacity configuration was done. Because of superior characteristics, Vanadium redox flow battery could get a better economy with large-scale access.更多还原