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针对由启动电池和动力电池构成的电动汽车储能系统,利用启动电池功率密度高的特点与动力电池组结合构成混合储能系统作为负载的供电单元,为避免动力电池组长时间大电流放电和延长动力电池组寿命,设计改进型逻辑门限混合储能控制策略,改善混合储能系统内部能量均衡,并能有效提高储能系统电池使用效率。仿真比较了常规逻辑门限控制策略和改进型逻辑门限控制策略的差异,并进一步通过实验验证改进型逻辑门限控制策略的可行性。结果表明,改进型逻辑门限控制策略能够更好地改善动力电池组输出电流大的问题,并很好地实现了动力电池组和启动电池组的能量均衡。 相似文献
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Ken'Ichi Narita Nobunao Takeuchi Noriyoshi Chubachi Noriyasu Honma 《Electrical Engineering in Japan》1998,125(4):34-42
The variations in atmospheric electrical field signals in fair weather were observed both at Aobayama in Sendai and at Tsukidate in the Miyagi Prefecture. The measurements were made using a slow antenna type electrical field meter composed of a metal plate electrode and a CR integrator. They were recorded using a portable pen-recorder. A field meter of this type is suitable for measuring relatively rapid variations. The observations were made in a period of a few minutes in fair breezy weather. The data collected using a bare metal electrode were compared with those using an insulated electrode in order to detect an air-earth current. Examination of the dependence of the amplitude of the variation to the electrode size and height showed that the atmospheric electrical field is affected by these parameters. Observation of signals at two different positions gave the time delay between positions. This indicated that the electrical field perturbation was about several hundred meters. The well known atmospheric circulation with a period of a few minutes suggests that the observed variations in the electrical field signals were caused by electrical charges moving together with the atmospheric circulation. © 1998 Scripta Technica, Electr Eng Jpn, 125(4): 34–42, 1998 相似文献
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储能具有调峰幅度大、响应速度快等优点,对未来电网发展具有深远的影响。近年来,储能技术迅猛发展,为充分发挥全钒液流电池储能系统相较于传统电池储能技术的优势,对全钒液流电池储能系统进行了仿真研究。首先,根据全钒液流电池的基本结构分析了其原理及特性,搭建了全钒液流电池的电气模型。然后,对储能逆变器连接储能电池和电网的两种控制策略,定功率(PQ)控制策略和定电压频率(VF)控制策略分别进行了建模和仿真验证。最后,以北海热电厂为实际应用场景,将所搭建的储能电站模型应用于黑启动方案中。启动储能逆变器后,北海热电厂的厂用母线电压可以稳定维持在0.96 p.u,表明了利用储能电站进行黑启动的可行性,验证了储能电站模型的有效性。 相似文献
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免维护蓄电池在运行中的维护方法 总被引:1,自引:0,他引:1
针对河津电厂使用的德国阳光免维护电池及其它电厂的免维护电池在运行中出现的问题,从运行的角度,介绍了几种日常工作中的维护方法,主要有:充电电压的整定、环境温度对充电电压的影响、蓄电池的检测、充放电维护等。使其在运行中少出问题,延长寿命,更好地服务于电力系统。 相似文献
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碱性蓄电池的记忆效应 总被引:2,自引:0,他引:2
含有Cd电极和Ni电极的碱性蓄电池,由于某种固定或不规范的充放电制度,引起Cd电极中晶体增大,比表面积减小,或使Cd电极中形成新的合金而钝化;造成Ni电极膨胀或生成不导电的Ni(OH)2而引起电池电压下降或容量减少的现象,即电池的记忆效应。碱性蓄电池的记忆效应可以通过调整电极的配方、改变电极的制作方法和调节充、放电循环得到消除或减轻。 相似文献
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电动车用MH-Ni动力电池 总被引:14,自引:4,他引:14
对近年来电动车用MHNi动力电池开发动向进行了简要综述。从动力电池角度而言,MHNi电池与现有正开发的各种电池相比,具有更强的现实应用性,其比能量已与锂离子电池水平相当,体积比功率甚至高于锂离子电池水平;从发展态势上看,MHNi动力电池主要有适合纯电动车用的高能MHNi动力电池和适合混合动力车使用的高功率MHNi动力电池,不同类型的动力电池有着不同的电池结构设计及电极组成。与此同时,对构成其电极的活性物质成分、一些改性措施及存在的问题、发展趋势及国内MHNi动力电池发展等进行了评述 相似文献
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风电并网存在功率及公共耦合点(Point of Common Coupling, PCC)电压波动问题,常规方法为采用储能装置与无功补偿装置分别进行调节,但会导致系统结构复杂。文中研究了一种基于模块化多电平变换器拓扑的电池储能系统(Modular Multilevel Converter Based Battery Energy Storage System, MMC-BESS),可对风电场功率及电压进行综合调节。由于风速的随机性导致风电场输出功率波动,提出将风电场有功功率输入到一阶低通滤波器中,滤波器输出与输入的差作为MMC-BESS有功参考信号,以平滑风电场并网功率。由于风电场负荷突变导致PCC电压波动,提出将PCC电压的d轴分量与额定值作差,通过PI调节生成无功参考电流,实现PCC电压调节,在模拟风电场场景下进行实验,实验结果验证了风电场中MMC-BESS四象限功率补偿能力。 相似文献
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Xiao S. Joshi R.P. Kolb J.F. Schoenbach K.H. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2009,16(4):1066-1075
Spark gaps, which use water as a switching medium, allow fast closing and high repetition rate operation for high power and high voltage switching. They are usually operated in the pulse-charging mode and have a large jitter. To reduce the jitter, a trigger electrode with positive polarity is used to initiate breakdown between a negative high voltage electrode and a ground electrode. The trigger electrode consists of a tungsten wire with a diameter of 50 μm, enclosed in glass tubing. At the triple point where the three dielectrics (glass, water and metal) meet, the electric field is greatly enhanced. From the triple point, a trigger voltage of +16 kV at a pulse duration of 100 ns produces two streamer branches traveling towards the high voltage and ground electrodes. These two streamer branches bridge the main gap and serve as preionized channels for the initiation of the breakdown between the main electrodes. Arc transition develops along the two channels and completes the switching. It allows for the gap to be fired at various voltages independent of the gap?s self-breakdown voltage. The delay between application of the trigger pulse and the electrical breakdown is on the order of hundred nanoseconds. The jitter in breakdown is on the order of ten nanoseconds. It is less by more than an order of magnitude than that obtained with pulse charging. 相似文献
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研究了MH Ni电池、Cd Ni电池在充放电过程中的内阻变化及内阻与放电电压平台的关系。试验结果表明 ,在充放电过程中 ,内阻变化受正负极活性物质氧化态 /还原态的转化反应影响 ,充电过程与内压有关。在正极中添加钴、镉氧化物 ,在Cd Ni电池负极中采用PLB新粘合剂 ,可有效地提高电池内部气体的复合性能 ,减小电池内阻。电池内阻小 ,放电电压平台高 ,有利于延长高波放电电压的时间。 相似文献
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电池储能系统BESS(battery energy storage system)串并联结构可以实现小容量低电压等级储能系统接入直流微电网的应用,可以提高端电压且实现储能系统扩容。针对直流微电网BESS的串并联结构,提出一种基于电池荷电状态SOC(state of charge)的分散控制方法。该方法可以实现反下垂控制分配串联模块间电压与下垂控制分配并联模块间功率的目标,且反下垂特性不影响下垂外特性。通过低带宽通信将所有电池SOC信息上传到中央控制单元得到每个BESS的下垂系数与反下垂系数,可以有效实现不同BESS间按容量精确分配功率的目的,消除电池差异延长寿命,避免过放。通过建立小信号模型,分析系统稳定性;通过搭建Simulink仿真模型,验证分散控制的可行性与有效性。 相似文献
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蓄电池的各项参数反映了其本身的性能,对用电设备的正常运行具有极其重要的意义,为了实现在线、准确的测量蓄电池的各项参数,以现场可编程门阵列(FPGA)为核心设计了一种蓄电池参数检测仪。采用交流注入法测量蓄电池的内阻,专用芯片LTC2943测量蓄电池的电压、充放电电流、温度和剩余电量等参数。对新旧蓄电池内阻进行了对比测试,对单节蓄电池进行了其他参数的测试。结果表明,该设计使用方便、可靠性较好、测量精度较高,具有较高的实用价值。 相似文献
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YUUKI WADA NAOKI NOBUNAGA SHINYA KUMAGAI HIROKI ISHIHARA MAKOTO ISHII MINORU SASAKI 《Electrical Engineering in Japan》2018,203(1):58-64
The Si resonator is applied for measuring the voltage in a highly isolated manner. The working principle is based on the resonant frequency shift caused by the electrical field from the electrode connected to the high‐voltage source (supposing the battery). Here, the resonator is electrically floated, and its potential is decided by the relative position against the electrodes which are connected to the high voltage and the driving voltage. The induced voltage on the resonator is analyzed against the driving frequency. The resonance is found by the paired peaks in the amplitude curve. The setup for the electrical measurement can make the sensor system compact. A new sensor design for avoiding the electrical field concentration realizes the measurement over 400 V without the breakdown. This will match with the high‐voltage dc power supply system. 相似文献
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炭黑对锌空气电池空气扩散电极电性能的影响 总被引:3,自引:3,他引:0
为了研究炭黑对锌空气电池空气扩散电极电性能的影响,选用不同种类的炭黑作为锌空气电池空气扩散电极的导电剂,采用辊压法制备出空气扩散电极,测试了空气扩散电极的含液率、极化曲线、使用寿命和所得AA型锌空气电池样品的放电容量,还利用扫描电镜(SEM)对空气扩散电极催化层的表观形貌进行了观察。研究结果表明,Shawinigan Black AB 50炭黑的疏水性最好,所得空气扩散电极的含液率最低、电性能最好、使用寿命最长,所制AA型锌空气电池样品的放电容量可达4.6 Ah。 相似文献