The application of Flexible DC power transmissi on and Flexible AC power transmission technology in modern power system improves the conversion and transmission efficie ncy of electric energy, enhances the control ability and flexibilit y of power grid, and greatly improves the absorption capacity of new energy such as solar energy. Flexible transmission tech nology plays an important role in achieving the goal of carbon peak and carbon neutrality. In order to strengthen the combin ation of theory teaching and engineering practice, the author se ts up the physical model of the flexible transmission system in t he power system dynamic simulation laboratory, designs the ex perimental teaching content, and integrated it into the course o f Comprehensive Experiment of Modern Power System, and carr ied out the teaching experiment. The practice results show that through the training of experimental teaching, the students hav e deepened their understanding of the theory knowledge of flex ible transmission system, accumulated the operation experienc e of flexible transmission equipment, and improved the student s' ability to master and apply the flexible transmission technolo gy.

Algorithms are proposed to address the radar target detection problem of compressed sensing (CS) under the conditions of a low signal-to-noise ratio (SNR) and a low signal-to-clutter ratio (SCR) echo signal. The algorithms include a two-stage classification for radar targets based on compressive detection (CD) without signal reconstruction and a support vector data description (SVDD) one-class classifier. First, we present the sparsity of the echo signal in the distance dimension to design a measurement matrix for CD of the echo signal. Constant false alarm rate (CFAR) detection is performed directly on the CD echo signal to complete the first-order target classification. In simulations, the detection performance is similar to that of the traditional matched filtering algorithm, but the data rate is lower, and the necessary data storage space is reduced. Then, the power spectrum features are extracted from the data after the first-order classification and converted to the feature domain. The SVDD one-class classifier is introduced to train and classify the characteristic signals to complete the separation of the targets and the false alarms. Finally, the performance of the algorithm is verified by simulation. The number of false alarms is reduced, and the detection probability of the targets is improved.

OBJECTIVE:The aim of this study was to characterize the subsets of circulating CD56+ NK cells in pSS patients and their potential value in the diagnosis and/or prediction of prognosis in patients with pSS.METHODS:We included 52 pSS patients fulfilling the 2002 AECG criteria or 2012 ACR criteria and 20 age- and gender-matched healthy volunteers. The frequency and absolute number of NK cells and CD56 NK cell subsets in peripheral blood samples were detected by flow cytometry. Other laboratory parameters such as the IgG level and complement protein levels were extracted from the clinical system.RESULTS:Both the frequency and the absolute number of peripheral blood NK cells were reduced in pSS patients compared to healthy controls. The proportion of CD56bright NK cell subset was increased, and the proportion of CD56dim NK cell subset was decreased among NK cells, resulting in the ratio of CD56bright NK to CD56dim NK which was significantly elevated in pSS patients. ROC analysis indicated that the AUC of CD56bright NK/CD56dim NK ratio was 0.838, and the best diagnostic cut-off point was 0.0487 for pSS patients. Furthermore, this CD56bright NK/CD56dim NK ratio was positively correlated with the IgG level and negatively correlated with the complement protein C3 and C4 levels. More importantly, the CD56bright/CD56dim NK ratio was either slightly increased or not changed in other autoimmune diseases such as SLE and IgG4-related disease.CONCLUSION:Our findings suggest that the ratio of blood CD56bright NK to CD56dim NK might have a diagnostic value relatively specific for pSS.

Existing arc generator is usually integrated with a simplified systematic Thevenin equivalent circuit to study the dynamic arc behavior. It cannot be used for the arc fault detection and location research in the neutral non-effectively grounded distribution system (NGDS) because the interaction between the arc fault and the distribution system is ignored. In this paper, one arc generator with additional fault condition control module is proposed, discussed and realized. At the meantime, one scaled-down NGDS is also realized to integrate with our proposed arc generator. The accomplished devices are detailed illustrated and discussed. The effectiveness of the proposed testing platform integrated with the analogous distribution system and the arc fault generator have been validated by the recorded voltage and current waveforms in the experiments

世界上首个特高压三端混合直流输电工程“昆柳龙直流工程”将在2021年建成投运,该工程是将云南大容量水电能源采用先进的直流输电技术送到广西和广东.为了研究特高压远距离架空直流输电线路各种故障特征,探索发现更好的直流保护新判据,分析了直流输电线路的零序电阻和电感频率特性,提出了换流站接地极简化模型,设计了昆柳线、柳龙线两条直流线路模型,建成了一套含接地极的完整分布参数动态物理模型.试验表明,该模型系统达到设计要求,能正确反映原型系统物理特性,可以开展不同故障点的各种类型短路实验,为直流输电技术研究提供了宝贵的试验数据.

研制了一种大容量高精度组合开关和具有多路参考电压的合闸角程序控制器,能够对开关跳合闸角度进行精确控制,实现了对电力系统的短路时刻、变压器励磁涌流实验角度和转换性故障的转换时间等精确控制;能动态模拟再现实际电力系统各种故障波形,能开展0～360°不同时刻的故障实验和故障波形分析.实验表明,该开关的控制精度可由原来的±5 ms提高到±0.1 ms,满足了科学研究实验需要.

This paper designs dynamic model system of a smart distribution network which can be used to analysis on ground fault and experimental study of self-healing control technology of the distribution network, as well as the system test of automation equipment, develops special equipment for carrying out fault location tests and faulty fault line selection test in ungrounded systems, and built the flexible power distribution system dynamic model system. The research achievements have been applied in many universities, power research institutes, ship propulsion system research centers in China.

In this paper, we handle the non-fragile consensus control problem for a class of discrete time-varying nonlinear multi-agent systems with uniform quantization and randomly occurring deception attacks. The quantization error is described by a noise distributed uniformly in certain interval, and the phenomenon of the randomly occurring deception attacks is depicted by the Bernoulli distributed random variables with known probabilities. Here, the measurement output utilized in the controller side is not only from a single agent itself, but also from its adjacent agents, where the corresponding transmissions are carried out under a given topology. In particular, the controller gain perturbations are characterized by the multiplicative noises. We focus on the design of non-fragile time-varying output feedback controller such that, when the randomly occurring deception attacks, uniform quantization effects as well as controller gain perturbations exist simultaneously, and the desired consensus performance is guaranteed by designing the controller parameters. Accordingly, a sufficient condition is derived to ensure the existence of the desired control scheme, where the feasibility of conducted problem can be tested by solving a set of matrix inequalities. Moreover, the optimal consensus performance is addressed by employing an optimization problem. Finally, we utilize the simulations to illustrate the feasibility of the proposed output feedback control strategy.

设计开发了一种基于转子位置测量法的动态功角测量装置,该装置不仅能实时跟踪测量发电机的动态功角和转速变化,还能测量电力系统中发电机对不同母线或者不同母线之间的功角.实验表明,该装置具有精度高 、功能多 、灵活性强等特点,能够满足实验教学和科研的需要.

针对配电网故障定位系统研究和试验检测存在的问题,对配电网动态模拟元件进行了研究,研制了升流器、升压器和零序电流互感器等特殊模型实验设备,搭建了一种能开展接地故障分析、小电流接地选线装置试验及故障指示器系统性测试的配电网动态模型.试验表明,该动态模型可以开展故障定位及配电自动化产品的测试研究,成果已推广到国内多所高校和电科院.

本文基于笔者多年来指导电气工程专业的学生从事科研训练与大学生创新创业项目的心得体会,借鉴国外高校的一些实践经验,以及乔布斯的成功启示,对大学生科技创新活动这一非课堂培养平台进行探讨,希望从中总结出一条行之有效的人才培养途径,供践行者参考.

提出一个快速的三维彩色全身人像捕捉系统(名为化身1号):1.5s采集数据,1 min内全自动地建立三维全身人像.化身1号使用了8台自制的结构光扫描仪,采集数据的精度达到1mm.这8个扫描仪预先配置好空间位置:4个抓拍头部,4个抓拍身体.从而能够有效地覆盖采集成人对象的全身区域.在离线标定完8个扫描仪后,化身1号就可以捕获真实对象,在一个坐标系内处理各扫描仪采集的局部数据,历经全局注册和无缝隙的纹理拼接,鲁棒地建立高逼真度的纹理人像模型.该模型的几何精度达到1mm,并具有照片真实感的色彩信息.实验结果表明,在高逼真度建模需求的前提下,化身1号的采集和处理速度均处于当前最优水平.

This paper adopts the active disturbance rejection control (ADRC) technology to control the non-minimum phase system (NMP). A new amplifier called square-root amplifier (SQF) is added in the ADRC to reduce the undershoot and the settling times of the step response. Simulation results are given to verify the effectiveness of the proposed scheme.

The paper briefly introduces the bug of Heartbleed including its basic concept and the process of finding,publishing,exploiting,evolving,repairing and preventing it.Then the paper analyzes the features of Heartbleed and presents some suggestions from four aspects which are as follows:safe communication protocol software,the importance of open source software,code management of open source software and the analysis and exploitation of open source software.

Mining the inherent persistence property of the time series of wind power is crucial for forecasting and controlling wind power. Few common methods exist that can fully depict and quantify the persistence property. Based on the definition of the active power output state of a wind farm, this paper describes the statistical persistence property of the duration time and state transition. Based on the results of our analysis of significant amounts of wind power field measurements, it is found that the duration time of wind power conforms to an inverse Gaussian distribution. Additionally, the state transition matrix of wind power is discovered to yield a ridge property, the gradient of which is related to the time scale of interest. A systemaic methodology is proposed accordingly, allowing the statistical characteristics of the wind power series to be represented appropriately.

This paper describes the basic concepts of information grid, and analyzes the typical information grid technology- the U.S. military's Global Information Grid(GIG), and discusses the generate impetus, trends and military application of information grid technology to.

Probabilistic load flow (PLF) calculation is the first step to evaluate the impact of the integrated wind power to the power system. The wind power is featured with stochastic and variable properties and it's hard to fit its distribution characteristics to any common probability density function (PDF). However, the traditional methods including Monte Carlo for PLF are based on the input variable's PDF. In the paper, the point estimate method and Gram-Charlier expansion method are combined. Based only on the sample data of the wind power, the expectation, variance and cumulative distribution of the output random variables can be estimated with the method by 2n+1 times of load flow calculation where n is the number of input stochastic variables, exempting the need for distribution of the input variables. The simulation results in the IEEE 16-generator system show that the method provides high precision with less computation burden. The method can also be applied to other problems with uncertainty factors whose distribution is unknown in the power system.

生产实习是本科生理论联系实际的重要培养环节。从生产实习的基本内涵、意义和要求着手分析，结合具体生产实习的实例，说明当前电力系统及其自动化专业本科生生产实习存在的一些问题，并提出了解决的建议。

This paper discusses the concept connotation and extension of research-oriented university.Taking the electrical engineering courses for example,it enumerates the undergraduate traning of three Asia representative research-oriented university: Nanyang Technology University,Hong Kong Polytech Unversity and Huazhong University of Science and Technology.It analyzes each on theire own advantages and characteristics,which shows that the collaborative innovation training among these unversities is feasible and effective.It also proposes some advice on specific implementation pattern.

分析了供墨系统及其控制要求,构建了基于PLC、工业触摸屏及上位机(PC)的电气控制系统。设计采用OMRONCP1HPLC作为控制核心,实现了与上位机的数据交换。根据压力、温度的数据结果,触摸屏及上位机实时显示状态与报警。给出了相应PLC程序及人机界面。应用结果表明,该系统既可以实现上位机控制运行,又可以手动按钮操作,提高了工作效率。