光柴互补系统建模与改进MPPT控制策略

介绍了光伏电池原理,在MATLAB/Simulink中建立了光柴互补发电系统。采用Matlab的S函数编写了光伏电池MPPT控制器控制方法,并在当负载吸收功率小于光伏电池输出功率时,对控制器进行了改进,以防止功率流入柴油发电机。仿真得到负载工况变化下系统的功率、电压曲线,验证了改进的MPPT控制器的可行性。     

光伏电池、组件、阵列的精确模型仿真研究

本文介绍了一种实际应用中的光伏电池、光伏组件和光伏阵列的精确模型,阐述了光照和温度对输出电压、电流和功率的影响。最后参照DQ240PSCa/b型号的电池板详细参数进行仿真,对比了仿真结果。     

低压配网中光伏发电系统的电能质量分析

当前光伏发电系统在低压配电网中的应用日益增多.由于光伏系统本身的非线性特性以及出力的随机性,其并网时出力的波动必然会影响电网的电能质量.本文通过建立一个低压配网中的光伏发电模型,研究其并网时所产生的主要电能质量问题.考虑当光伏发电系统采用基于最大功率跟踪（MPPT）的有功无功解耦（PQ）控制方式时,在外部光照强度发生波动的影响下,观察光伏发电系统并网输出功率、电压及电流的波动,分析对低压配网照成的电能质量问题.通过仿真发现,在外部光照发生剧烈变化时,输出波动较大,光伏系统会向电网注入大量谐波,对电网的电能质量产生较大影响.     

新型智能锂离子电池组的研制

本文提出了一种新型智能化、高比能、高可靠性的锂离子电池组的研制方案。可对本体锂电池电压、电流、温度进行检测,并对锂电池在充放电过程中提供过压、过流、短路保护。另外该电池组还提供充放电、通讯及报警接口,通过显示模块实时显示单体端电压、电流、环境温度及故障信息等数据,并发出声光报警。     

混合直流断路器自然换流过程中弧压的测量及建模

混合式断路器的电流转移主要有自然换流和强迫换流两种方式,其中自然换流是在机械开关斥力机构驱动触头分闸过程中产生电弧电压的作用下迫使故障电流由机械开关向半导体开关转移的过程,该阶段电弧电压的大小及变化过程对转移时间有着至关重要的影响。本文通过实验精确测量12kA电流等级下真空电弧电压的大小及变化规律,并利用PSCAD/EMTDC建立电弧电压数学模型,最后将该电流等级下换流时间的仿真计算和实验实测结果进行对比,验证了真空电弧电压模型的可靠性与正确性。     

基于IGCT的三电平H桥型大功率变频器电子保护研究

基于三电平H桥型大功率变频器的拓扑结构及IGCT过电流能力,本文在考虑输入整流变压器短路阻抗及变频器主回路参数的情况下,深入分析了可能出现的各种不同的过电流故障模式,建立了瞬态故障等效数学模型,通过数值分析方法研究了各种故障状态下瞬态电流及电压的变化趋势,并对造成回路参数变化的原因进行了讨论。在此基础上提出了一种大功率...     

船舶柴油发电机组数学模型的仿真研究

本文以船舶柴油发电机组为例,针对三相交流发电机组做了较为深入的分析并建立起数学模型。在数学模型的基础上,利用MATLAB／Simulink平台搭建其仿真模型,并利用模拟负载针对所建立的仿真模型进行了仿真验证,分析了船舶同步发电机组在负荷变化时的电压、电流等状态参数的相关特性。     

基于SVPWM的三相电压型PWM整流器的研究

阐述三相电压型PWM整流器的拓扑结构及工作原理,建立了三相电压型PWM整流器在三相静止坐标系下及同步旋转坐标系下的数学模型,研究了电流前馈解耦算法、SVPWM算法.设计了三相PWM整流器控制系统的结构,并在Matlab中进行仿真,仿真结果证明这种控制结构的具有动态响应速度快,直流侧电压稳定,交流侧电流为正弦波,且电压电流同相位的优点,实现了单位功率因数,有效的抑制了谐波,同时表明设计方法可行,仿真模型正确.     

基于前馈解耦的三相逆变器双环控制器设计

建立了两相同步旋转坐标系下三相逆变器数学模型,构建了其电压电流双环控制方案。为了提高系统的动态响应特性及抗扰能力,在电压外环和电流内环中引入了前馈控制和解耦控制,并由此提出该控制器的设计方法,通过40k VA样机实验表明,该控制器具有良好的动态和稳态性能。     

基于强化学习的船舶微电网能量管理策略

全电船舶将柴油发电机、电池储能系统、光伏发电系统相结合，以电能形式满足船舶日常各类运行的需求，提升了船舶能量的利用效率。然而，受到光伏强度和环境温度不确定性的影响，光伏发电系统的有功出力曲线呈现随机性和波动性，进而导致船舶微电网能量管理策略需要兼顾最优性和鲁棒性。为制定有效的能量管理策略，提出一种基于强化学习技术的全电船舶微电网能量管理模型及算法来克服不确定性的影响，算法求解得到的能量管理策略能根据随机性因素的实时变化动态修正，可保持船舶能量消耗处于最优状态。最后通过算例验证了所提算法的可行性和有效性。     

Errata

正In the paper"Influence of Fouling Assemblage on the Corrosion Behaviour of Mild Steel in the Coastal Waters of The Gulf of Mannar,India"in Vol.12,No.4,Page:509,References were lost,and the two authors’biographies were identical.The correct text is shown below.We apologize to the authors and our readers for any inconvenience caused by the errors.     

Journal of Marine Science and Application 2014 Sum. Contents

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第34届海洋、离岸及极地工程国际会议(英文)

正St.John's,Newfoundland,Canada,May 31-June 5,2015 OMAE2015 is the ideal forum for researchers,engineers,managers,technicians and students from the scientific and industrial communities from around the world to: meet and present advances in technology and its scientific support;     

联合作战计划和执行系统

全球指挥控制系统(GCCS)实施当前美国海军网络中心战信息基础设施的联合计划网络。联合作战计划和执行系统(JOPES)支持GCCS实现联合计划。JOPES有两类计划：时间不限的精密预案计划生成作战计划、方案计划或职能计划；时间敏感的危机行动计划生成作战命令或战役方案。前者在和平时期创建的作战计划是后者的计划基础，加速应付危机的能力。     

Eastbound or westbound ?

In terms of equal sailing distances, where is the inflexion when ships depart from ports in the Asian Continent to New York via Suez and/or Panama？
The answer is China South Port Group （Hong Kong, Shenzhen and Guangzhou）.     

Recent progress on wave induced loading measurements in warships

Recent measurements of wave induced hull strain and flexure in RN warships are presented together with the derivation of the current design criteria for extreme hull girder bending loads. The history of the development of the shipboard instrumentation used is given and recent developments to improve the quality and ease of analysis of the data are described. An unexpectedly high transverse asymmetry in the longitudinal strains measured in destroyers is shown to be the result of a combination of vertical and lateral bending in oblique seas. Finally recent theoretical comparisons between the loading of Deep-Vee hulls and conventional UK rounded bilge hulls are presented which demonstrate the higher loading experienced by this type of hull form.     

桥梁防撞设施物理模型试验

物理模型试验是预报防撞设施所受撞击力及优化设计方案的主要方法之一。结合杭州湾大桥柔性防撞设施及东海大桥独立式防撞体设计方案,阐述了船—防撞体撞击试验的基本原理、方法、试验方案及相关试验结果。提出了柔性防撞系统的优化方案。试验结果表明,该方案经济有效,可供预报类似桥梁防撞设施撞击力时参考。     

印尼某电厂码头水工建筑物设计

印尼某电厂项目码头水工建筑物包括码头、防波堤和护岸等主要组成部分。在该项目水工建筑物的设计过程中,综合考虑当地的自然条件、施工能力和材料来源等因素,不断优化结构选型和结构断面。根据不同使用要求,护岸分别采用直立式和斜坡式2种结构型式,推荐的设计方案节省投资、施工方便,可供同类工程设计参考。     

Impact of regulation on the performances of long-distance transport services: A comparison of the different approaches in Sweden and Norway

Despite the many socio-economic similarities between Sweden and Norway, differences in jurisdiction, organisation, cooperation, and financing of long-distance passenger train and coach services have led to the development of four distinctively different ways of serving the markets. This paper describes how the train and coach markets have developed in the two countries, with emphasis on regulatory and industrial structure and a couple of performance variables.Looking at passenger rail, both countries separated infrastructure from operation over a decade ago. However, while Norwegian rail is characterised by an almost monopoly supplier, rail services in Sweden are partly decentralised to the responsibility of county authorities and are widely subjected to competitive tendering. The rest of the network is about to be opened up for on-the-track competition. Swedish Rail (SJ) has spent the last decades consolidating its core business (passenger rail) and sold out its other businesses. In contrast, the Norwegian state rail (NSB) has expanded its business to become a major bus operator and property owner, with extensions also into the Swedish market.The coach industry was more recently deregulated in both countries. The Swedish coach market is dominated by privately owned companies operating services to and from Stockholm. In Norway, state-owned NSB is a major coach operator on medium distance routes, and is also the largest partner of Nor-Way Bussekspress which totally dominates long-distance coach services. Further, the Norwegian coach market is characterised by cross-ownership and cooperation which has enabled an extensive route network which covers most of Norway.We find distinct differences in achievements in the two modes and in the two countries. Swedish rail services have succeeded in winning market shares and in renewing and developing both infrastructure and service levels to a greater extent than the Norwegian model. On the other hand, the Norwegian coach market seems to be more developed and efficient compared to its Swedish counterpart.The paper concludes with a discussion on the possible links between the different approaches and the performance observed, with the aim to stimulate further and more detailed research on some important issues.     

开放式数据挖掘系统模型

目前国内已经出现了少量的数据挖掘相关产品。国内数据挖掘软件无论从数量还是质量上比较，都与国外软件存在着较大的差距。随着数据仓库技术的普及，数据挖掘应用的需求越来越强烈，如何缩短这种差距，研发数据挖掘软件产品成为国内业界的一个重要问题。通过引用目前国际通用数据挖掘标准技术来构建开放式的数据挖掘系统模型，该系统模型从可扩展性、可重用性、易用性等方面得到了加强。