Grid-Connected Emergency Back-Up Power Supply

This paper documents design and modeling of a grid-connected emergency back-up power supply for medium power applications. Back-up power supplies are very important in regard to support electrical loads in the events of grid power outage. However, grid-integration of a back-up power supply substantiates continual power transfer to the loads, especially to the critical loads, which should not suffer from power interruptions. Therefore, design and circuit modeling of switching converters based reliable grid-tied emergency back-up power supply are presented in this paper. There are a rectifier-link boost derived battery charging circuit and a 4-switch push-pull power inverter circuit which are controlled by high frequency pulse width modulation (PWM) signals. This paper presents a state averaging model and Laplace domain transfer function of the charging circuit and a switching converter model of the power inverter circuit. A changeover relay based transfer switch controls the power flow towards the utility loads. During off-grid situations, loads are fed power by the proposed inverter circuit and during on-grid situations, battery is charged by an ac-link rectifier-fed boost converter. However, there is a relay switching circuit to control the charging phenomenon of the battery. The proposed design is simulated in PLECS and the simulation results corroborate the reliability of the presented framework.

Sleep and Stress of Late Middle Age Males Who Are Forced to Live in Emergency Temporary Houses and Post-Earthquake Public Houses for a Long Period Due to the Fukushima Daiichi Nuclear Power Station Accident

It has been revealed that prolonged shelter life caused by Fukushima Daiichi Nuclear Power Station accident in conjunction with the Great East Japan Earthquake influences sleep and mental health of the residents, and therefore its influence on their physical and emotional health has become a concern. Therefore, in this study, the authors aimed at clarifying actual situations of sleep and stress of middle age males living in shelters for a long period in each of emergency temporary houses and post-earthquake public houses. For 5 males who moved from emergency temporary houses to post-earthquake public houses, their objective and subjective sleep states were measured with Actigraph and PSQI, respectively. Furthermore, their objective and subjective stresses were measured with saliva stress biomarkers and GHQ28, respectively. Their data were analyzed by paired t-test. As result, in comparison between the life in the emergency temporary houses and post-earthquake public houses, significant variation was not recognized in their objective sleep states and saliva stress biomarkers though their subjective sleep and subjective stress were significantly worsened after moving to the post-earthquake public houses.

A framework for nuclear power plant emergency response system

The purpose of this study is to establish an intelligent expert system for nuclear power plant emergency response.A new framework of environmental risk management methodology by the concept of pattern recognition was introduced in this paper.A knowledge-based decision support system for emergency response and risk management of nuclear power plant was also discussed.The mathematical pattern relationship of accidental release effects on neighboring area and the corresponding response measures were presented in this paper.With this decision system,the decision maker can specify the procedure and minimize their human error in the decision process.The improvement of risk response and the quality of management system could be upgraded by this system.Besides,the methodology can also be served as a basis for the future development of environmental risk response system design.

DC Emergency Power Control Strategy for AC/DC Multi-Channel Interconnected System

Inter-regional transmission line fault often results in power flow transferring, tie-line overloading and system islanding. Traditional control methods such asgenerator tripping and load shedding are costly, and also have undesirable impacts on theloadside. In this paper, a new emergency power control strategy is proposed for multi-channel interconnected system by using the overload capacity of non-fault DC lines. First of all, the capacity of emergency power control can be acquired by critical transmission power of a certain tie-line for stability. Secondly, the shortest electric distance can be calculated by Dijkstra algorithm, and then the priority of emergency control of the DC lines can be obtained by the entropy weight method. When the inter-regional transmission power decreases and the effect of single DC line emergency control is poor, the multi-channel cooperative emergency control strategy is proposed to ensure the system stability. Simulation results verify the effectiveness of the method proposed.

An LCC-HVDC Adaptive Emergency Power Support Strategy Based on Unbalanced Power On-Line Estimation

HVDC auxiliary power control can significantly improve the transient stability of AC/DC power grid.An HVDC adaptive emergency power support method based on unbalanced power on line estimation is proposed in this paper.By establishing the extended state equation of the system,the on line dynamic estimation of unbalanced power of the system was realized.On this basis,power support was realized based on the principle of the ladder increment.The optimal DC was selected by the power support factor,and the emergency power support controller was installed on the DC.This emergency power support method can realize dynamic optimal power support with minimized control cost.The three infeed HVDC system was built on PSCAD.The simulation results show the effectiveness of the proposed method.

Police Emergency Commitment Powers in Cases of Persons Experiencing Mental Health Crisis in “Public Spaces”: Review of the Commitment Process in England and Wales, in Comparison to the Practice in the United States of America (USA)

Police emergency commitment powers for detention of persons in the community perceived to be seriously mentally ill for further specialist examination in a designated facility have always raised interest in medical and legal circles on both sides of the Atlantic. The objective of this article is to detail the police commitment procedure in England and Wales, as dictated by the mental health act of 1983 (MHA 1983) amended in 2007 (MHA 2007);and compare this with similar legal provisions as prevails under current state mental health statutes in the United States of America (USA). The comparative review of the commitment processes in England and Wales to that of the USA reveals that the process in England and Wales seeks to primarily ensure that persons with mental disorder (PWMD) in crisis are directed to a specialist hospital for evaluation and appropriate specialist care. In the USA such persons in a good number of cases may end up in the criminal justice system due to application of the “dangerousness” standard. Additionally whereas in England and Wales the commitment law is uniform in law and application, the federal system in the USA is such that the commitment law may have minor variations depending on the individual states. The minor variation in state commitment laws may engender a situation where the commitment law in England and Wales may seem relatively equitable and just towards PWMD in crisis, compared to the state commitment laws in the USA.

The CBD,Emerging Power

Central Business District (CBD), a concept that was first proposed by U.S.scholars in the 1920s, refers to a business center that functions as a commercial trading,finan- cial information,cultural center,exhibition and office area all rolled into one:a place that is the center of business,the driving power of urban economic development and the soul of a city.

Emerging Powers and Africa:A Comparison of Modes of Engagement Pursued by China,India and Brazil

The world has seen a relative power shift from the North to the South.The leading emerging states like China have taken up an increasingly commanding role in global economic affairs in response to the trauma experienced by Western industrialized states.Over the last decade and a half emerging powers have made significant inroads into previously the"bastion"of Western political and economic dominance,resulting in a diversifying external actors involved in African economy with much of this interaction bein...

Risk Communication and External Emergency Plan in Angra dos Reis, Brazil

The presence of a potentially hazardous facility in a community demands several safety procedures. Bringing risk communication among those actions may help the population that lives near the facility feel more confident and have the required knowledge on how to behave in an emergency situation. A research performed in Angra dos Reis, RJ, Brazil, where a nuclear power plant is located, shows that there is a lack of information and awareness about the emergency plan.

Low Power Computing Paradigms Based on Emerging Non-Volatile Nanodevices

Traditional digital processing approaches are based on semiconductor transistors, which suffer from high power consumption, aggravating with technology node scaling. To solve definitively this problem, a number of emerging non-volatile nanodevices are under intense investigations. Meanwhile, novel computing circuits are invented to dig the full potential of the nanodevices. The combination of non-volatile nanodevices with suitable computing paradigms have many merits compared with the complementary metal-oxide-semiconductor transistor （CMOS） technology based structures, such as zero standby power, ultra-high density, non-volatility, and acceptable access speed. In this paper, we overview and compare the computing paradigms based on the emerging nanodevices towards ultra-low dissipation.

Scavenging Microwave Wireless Power:A Unified Model,Rectenna Design Automation,and Cutting-Edge Techniques

While sufficient review articles exist on inductive short-range wireless power transfer(WPT),long-haul microwave WPT(MWPT)for solar power satellites,and ambient microwave wireless energy harvesting(MWEH)in urban areas,few studies focus on the fundamental modeling and related design automation of receiver systems.This article reviews the development of MWPT and MWEH receivers,with a focus on rectenna design automation.A novel rectifier model capable of accurately modeling the rectification process under both high and low input power is presented.The model reveals the theoretical boundary of radio frequency-to-direct current(dc)power conversion efficiency and,most importantly,enables an automated system design.The automated rectenna design flow is sequential,with the minimal engagement of iterative optimization.It covers the design automation of every module(i.e.,rectifiers,matching circuits,antennae,and dc–dc converters).Scaling-up of the technique to large rectenna arrays is also possible,where the challenges in array partitioning and power combining are briefly discussed.In addition,several cutting-edge rectenna techniques for MWPT and MWEH are reviewed,including the dynamic range extension technique,the harmonics-based retro-directive technique,and the simultaneous wireless information and power transfer technique,which can be good complements to the presented automated design methodology.

Global Power Structure Shifted and Transitional Multi-polarity Emerged

The world is facing the third important global power shift.The United States,EU, Japan,Russia,China,and the newly emerging power group are becoming the six big forces in the international center stage,while the former three forces and the latter three belong to two groups,waning and waxing respectively.The major shift in the global balance of power is bound to give rise to the transitional multi-polar configuration,which implies a shifting of leadership over the configuration,China and U.S.outweighing other forces,global issues looming large,homogeneity blending with heterogeneity,and a shifting center of world powers.The transitional multi-polar configuration is all about change,upon which China is one of the decisive forces.

大国兴衰与国际秩序的历史演进

大国兴衰与国际秩序的历史演进有着非常密切的联系。尽管近代以来国际秩序的具体形态不断发生演变,大国之间的力量对比不断发生改变,但欧洲和西方大国始终是国际秩序的主导力量。二战结束之后,摆脱了殖民地或半殖民地地位的非西方大国开始登上世界舞台。冷战结束后,一批非西方大国在新一轮的经济全球化进程中乘势而起,改变了大国之间力量对比结果,促成了“世界百年未有之大变局”的到来。相比于西方大国,非西方大国不仅具有更为广阔和长远的发展优势,更有不同的历史经验和价值追求,从而为国际秩序的发展变化注入了新的活力。而中国提出“人类命运共同体”理念构想和“全球发展倡议”“全球安全倡议”“全球文明倡议”,更是为超越当今世界所面临的挑战和困局,构建更为公正、合理的国际秩序,提供了令人鼓舞的发展目标和前景。

项目驱动教学法在“电力电子技术”教学中的应用——以“电场式无线输电”为例

目的:面向新工科背景下的育人要求,引入电场式无线输电项目,探究项目驱动教学法在《电力电子技术》教学课堂的应用。方法:教师讲解电场式无线输电项目传输原理后,将电场式无线输电项目中前级电路和后级电路拆解为逆变电路和整流电路,学生结合《电力电子技术》课堂内容自主搭建电路并进行仿真,在完成逆变电路和整流电路搭建后,教师指导学生尝试搭建电场式无线输电结构电路,得出传输结果。结果:全体学生均完成逆变电路和整流电路的搭建,其中70%左右的学生完成了电场式无线输电结构的搭建和仿真。结论:从学生的课堂表现和课后作业完成情况看,项目驱动教学法极大地提高了学生的学习兴趣,学生主动参与项目,不仅增强了学生的动手能力,还提高了学生的创新能力。

融合交通态势修正的台风灾害后多维度智能调拨策略

针对台风灾害后交通信息不确定、调拨策略考虑维度不足等问题,提出融合交通态势修正的台风灾害后多维度智能调拨策略。采用历史交通态势数据拟合道路通行时间概率分布,并基于拉丁超立方采样对交通态势进行随机抽样,以计算更准确的道路通行时间。考虑交通、电网、用户等多维度,以抢修队伍、抢修物资、应急发电车等作为调拨主体进行台风灾害后抢修调拨,提出考虑调拨距离、恢复时间、失负荷量最优的多维智能调拨策略,利用模糊隶属度函数求取帕累托前沿最优调拨方案。根据2018年台风“山竹”下的珠海市数据验证调拨策略的有效性。算例结果表明所提多维度智能调拨策略能有效缩短台风灾害后恢复进程,提升电网防灾减灾能力。

电力系统两阶段紧急切负荷控制智能预决策

电力系统仿真分析是安全稳定控制领域重要技术,可以用于制定与校验紧急控制措施。传统的人工分析仿真数据以决策紧急控制措施的工作模式严重依赖专家经验,在应用于复杂大电网时显得耗时耗力。该文提出一种两阶段紧急切负荷控制智能预决策方法,第一阶段决策切负荷点,第二阶段决策切负荷量。首先基于仿真数据,区分3种电压失稳模式:纯电压失稳、耦合电压失稳和混合电压失稳,分别采用不同的负荷筛选方法;然后基于轻量级梯度提升机算法,根据仿真数据直接预估系统恢复稳定所需的切负荷总量,按负荷排序进行分配。结合暂稳仿真校验控制措施的有效性,调整决策量。以我国东北电网为例进行仿真研究,验证了在大电网紧急控制措施制定时,所提两阶段智能决策方法相比完全迭代试凑方法在有效性、快速性和准确性方面的优势。

面向直流受端新型电力系统暂态电压稳定的紧急控制策略

在直流受端新型电力系统中,新能源电源及直流的接入导致同步机开机减少,动态无功功率相对紧张,暂态电压失稳风险显著增大。为高效快速获取紧急控制策略,即直流电流控制方案,并使其适应不同的电网运行方式和故障场景,尤其是电网拓扑结构的变化,基于图卷积神经网络(GCN)对常规深度强化学习模型深度确定性决策梯度(DDPG)的网络结构进行改造,构建了GCN-DDPG融合模型。在此基础上,引入双评价网络机制和评价网络与动作网络非同步更新策略以提升算法效果。进一步地,在应用方面,基于GCN-DDPG融合模型构建紧急控制模型并将其下达至安控主站,安控主站将依据电网实际运行方式和故障等信息,对紧急控制策略进行在线量化计算,并发送至直流控保系统执行。最后,通过改造的IEEE 14节点系统验证所提方法的有效性和优越性。

金融应急管理程序法治论

重大突发事件的爆发对金融机构和金融体系带来的重创可能造成系统性风险。通过金融应急管理权来实施紧急状态的金融治理是各国监管当局的共识。金融应急管理权具有应急性、管理主体的多元性和权力扩张的天然性,这决定了必须通过程序法治对其实施规范治理。金融应急管理程序法治的构建须坚持合法性原则、协同应急原则、保护金融消费者合法权益原则和保持透明度原则,围绕金融应急管理的启动、运行和退出程序展开具体的法律制度设计。