A Pragmatic Method to Determine Transient Stability Constrained with Interface Real Power Flow Limits via Power System Scenario Similarity

In practical power systems,operators generally keep interface flowing under the transient stability constrained with interface real power flow limits(TS-IRPFL)to guarantee transient stability of the system.Many methods of computing TS-IRPFL have been proposed.However,in practice,the method widely used to determine TS-IRPFL is based on selection and analysis of typical scenarios as well as scenario matching.First,typical scenarios are selected and analyzed to obtain accurate limits,then the scenario to be analyzed is matched with a certain typical scenario,whose limit is adopted as the forecast limit.In this paper,following the steps described above,a pragmatic method to determine TS-IRPFL is proposed.The proposed method utilizes data-driven tools to improve the steps of scenario selection and matching.First of all,we formulate a clear model of power system scenario similarity.Based on the similarity model,we develop a typical scenario selector by clustering and a scenario matcher by nearest neighbor algorithm.The proposed method is pragmatic because it does not change the existing procedure.Moreover,it is much more reasonable than the traditional method.Test results verify the validity of the method.

高致病性PRRSV Nsp2变异株Power SYBR Green real time RT-PCR检测方法的建立

根据高致病性猪生殖与呼吸综合征病毒（PRRSV）Nsp2变异株Nsp2基因保守区的核苷酸序列设计合成了1对引物,建立了Power SYBR Green模式的实时荧光定量RT-PCR方法,用于检测高致病性PRRSV Nsp2变异株。以pMD-Nsp2质粒为阳性对照制作标准曲线,并对该方法的特异性、敏感性、重复性进行评价。结果显示,该方法只能检测到高致病性PRRSV Nsp2变异株的特异性扩增信号;检测线性范围广,在模板浓度为3.15×10^9-3.15×10^0copies/μL具有良好的线性关系,相关系数（r^2）为0.998;最低检测限为3.15copies/μL。对25份疑似高致病性PRRS猪病料的检测结果显示,该方法与病毒分离的符合率为100%。表明,建立的Nsp2-Power SYBR Green RT-PCR方法具有良好的特异性、敏感性和重复性。

Stochastic response analysis of noisy system with non-negative real-power restoring force by generalized cell mapping method

The stochastic response of a noisy system with non-negative restoring force is investigated. The generalized cell mapping （GCM） method compute the transient and stationary probability density functions （PDFs） real-power is used to Combined with the global properties of the noise-free system, the evolutionary process of the tran- sient PDFs is revealed. The results show that stochastic P-bifurcation occurs when the system parameter varies in the response analysis and the stationary PDF evolves from bimodal to unimodal along the unstable manifold during the bifurcation.

A Remote Real-Time Monitoring System for Power Quality

An introduction is made to the composition, design method and engineering application of a remote real time monitoring system of power quality in substations based on internet. With virtual instrument and network technique adopted, this system is characterized by good real time property, high reliability, plentiful functions, and so on. It also can be used to monitor the load of a substation, such as electric locomotives.

SRDAAR－QNPP：a computer code system for the real－time dose assessment of an accident release for Qinshan Nuclear Power Plant

The paper presents a computer code system 'SRDAAR- QNPP' for the real-time dose as-sessment of an accident release for Qinshan Nuclear Power Plant. It includes three parts:thereal-time data acquisition system, assessment computer. and the assessment operating code system. InSRDAAR-QNPP, the wind field of the surface and the lower levels are determined hourly by using amass consistent three-dimension diasnosis model with the topographic following coordinate system.A Lagrangin Puff model under changing meteorological condition is adopted for atmosphericdispersion, the correction for dry and wet depositions. physical decay and partial plume penetrationof the top inversion and the deviation of plume axis caused by complex terrain have been taken in-to account. The calculation domain areas include three square grid areas with the sideline 10 km, 40krn and 160 km and a grid interval 0.5 km, 2.0 km, 8.0 km respectively. Three exposure pathwaysare taken into account:the external exposure from immersion cloud and passing puff, the internalexposure from inhalation and the external exposure from contaminated ground. This system is ableto provide the results of concentration and dose distributions within 10 minutes after the data havebeen inputed.

Data—mining massive real—time data in a power plant：challenges,problems and solutions

Nowadays,the scale of data nomally stored in a database collected by Data Acquisition system (DAS) or Distributed Control System(DCS) in a power plant is becoming larger and larger,However there are abundant valuable knowledge hidden behind them.It will be beyond people's capacity to analyze and understand these data stored in such a scale databased.Fortunately data-mining techniques are arising at the historic moment.In this paper,we explain the basic concept and general knowledge of data-mining;analyze the characteristics and research method of data-mining;give some typical applications of data-mining system based on power plant real-time database on intranet.

Low-Power Operational Amplifier for Real-Time Signal Processing System of Micro Air Vehicle

A low-power complementary metal oxide semiconductor（CMOS） operational amplifier （op-amp） for real-time signal processing of micro air vehicle （MAV） is designed in this paper.Traditional folded cascode architecture with positive channel metal oxide semiconductor（PMOS） differential input transistors and sub-threshold technology are applied under the low supply voltage.Simulation results show that this amplifier has significantly low power,while maintaining almost the same gain,bandwidth and other key performances.The power required is only 0.12 mW,which is applicable to low-power and low-voltage real-time signal acquisition and processing system.

Multi-parameter real-time monitoring scheme for power transmission lines based on FBG sensors

A multi-parameter real-time monitoring scheme for power transmission line is proposed and experimentally demonstrated.The Fiber Bragg Grating(FBG)sensors are used to sensing the information of temperature and strain in the power transmission lines system,and a monitoring center based on client–server model is established to process and display the sensing information.Several FBG-based power transmission line temperature sensors interrogated based on the developed multi-parameter real-time monitoring scheme is experimentally investigated.The result shows that the system is very useful.

Research on Real-time Data Sharing in Power Integrated Automation System

The Power Integrated Automation System has a large amount of the real-time data, it needs to achieve data sharing in different modules in its own system, sometimes even needs to be shared with the other systems. The thesis discusses the characteristics and the ways of the real-time data sharing in the first place. Then, it compares the merits and drawbacks in different ways. Besides, it gives a viable resolution in different aspects, such as the design of the real-time database, the framework of the communication system and the design of the communication software, as well as the real-time data sharing in different systems.

Digital arc welding power supply based on real-time operating system

A digital arc welding power supply was designed with the advanced reduced instruction set computer machine （ARM） and embedded real-time multi-task operating system micro C/OS- Ⅱ. The ARM, with its powerful calculating speed and complete peripheral equipments, is very suitable to work as the controller of the digital power supply. The micro C/OS- Ⅱ transplanted in ARM, helps to improve the respondent speed against various welding signals, as well as the reliability of the controlling software. The welding process consists of nine tasks. The tasks of great significance on reliability of the welder, for example, the A/D conversion of current and voltage, enjoy top priority. To avoid simultaneous-sharing on A/D converter and LCD module, two semaphores are introduced in to ensure the smooth performance of the welding power supply. Proven by experiments ,the ARM and the micro C/OS- Ⅱ can greatly improve both the respondent speed and the reliability of the digital welder.

基于改进深度Q网络的虚拟电厂实时优化调度

深度强化学习算法以数据为驱动,且不依赖具体模型,能有效应对虚拟电厂运营中的复杂性问题。然而,现有算法难以严格执行操作约束,在实际系统中的应用受到限制。为了克服这一问题,提出了一种基于深度强化学习的改进深度Q网络(improved deep Q-network,MDQN)算法。该算法将深度神经网络表达为混合整数规划公式,以确保在动作空间内严格执行所有操作约束,从而保证了所制定的调度在实际运行中的可行性。此外,还进行了敏感性分析,以灵活地调整超参数,为算法的优化提供了更大的灵活性。最后,通过对比实验验证了MDQN算法的优越性能。该算法为应对虚拟电厂运营中的复杂性问题提供了一种有效的解决方案。

数模—动模混合仿真系统的接口建模与稳定性分析

为满足现代电力系统实时仿真的发展需求,数模-动模混合仿真系统结合实时数字仿真和物理动态模拟仿真的优点,成为现代电力系统研究的重要仿真方法。接口系统是混合仿真系统设计中的核心与难点。为了深入分析混合仿真系统的稳定性,对接口系统各个组成环节进行建模得到系统开环传递函数,分别根据劳斯判据和奈奎斯特判据研究开环传递函数中不同参数对系统稳定性的影响。理论推导表明接口系统中滤波器截止频率、接口延时和阻抗模拟比对系统的稳定性影响较大,并通过所搭建的混合仿真系统进行实验,实验结果表明不同参数对系统的稳定性影响与理论推导一致。

基于点估计仿射可调鲁棒优化的含储能电力系统实时调度

为应对大规模风电的接入,建立一种机组与储能联合参与自动发电控制的电力系统实时调度模型,并提出一种点估计仿射可调鲁棒优化来处理风电不确定性。不同于传统仿射可调鲁棒调度优化基准运行成本,点估计仿射可调鲁棒调度优化期望运行成本以提高系统经济性。提出利用确定性的点估计法来实现对期望运行成本的快速、精确评估。所提模型为一混合整数双线性约束问题,采用一种“预估-矫正”的凸化方法来求解该难题,预估阶段对储能的状态变量进行松弛,而矫正阶段直接对其状态变量进行矫正。最后,引入一种凸函数差优化进一步凸化2个阶段的双线性约束问题,以提高含储能实时调度的求解质量。在IEEE39、118以及300节点3个系统的仿真验证了所提模型及方法的有效性。

基于模型数据混合驱动的大规模双馈风电场并网数字孪生建模

当前双馈风机详细模型具有多时间尺度动态和复杂控制环节,导致建模困难、大规模双馈风电场并网详细仿真建模所需算力庞大的问题。实际风机并网外特性无法实时反馈到仿真系统中,同时风电场功率输出受到多方面如风速、风向、老化等影响,使仿真系统无法精确拟合真实电力系统。针对这一问题,该文构建大规模数字孪生双馈风电场并网的电力系统模数混合驱动模型,实现了风机与电网互动反馈的实时更新,降低了算力需求,同时与风机物理实体实时匹配的虚拟模型具备较高的输出精度,满足精细化仿真需求。文中每台双馈风机采用长短期记忆网络构建数据驱动模型,风电场架构及所并电网选取常用的物理仿真模型,以数字孪生技术实现风机物理模型维护、虚拟数据模型更新的双向反馈。算例通过真实量测数据测试,结果表明在不同工况下该双馈风电场并网数字孪生模型较传统模型具备更优秀的拟合能力与精准度,同时实现了虚拟模型的实时更新能力。该模型有助于在大规模风电场并网中探寻具体某台风机故障、控制方式变化、风速波动等情况,研究风机之间相互影响、电网出现扰动时对风电场的影响。

双有源桥型电力电子变压器电磁暂态实时低耗等效模型

电力电子变压器(PET)是柔性直流配电网中电能变换的关键设备。受仿真资源限制,现有PET电磁暂态(EMT)实时仿真规模较小,无法满足大容量系统硬件在环测试与快速仿真需求。文中提出一种双有源桥(DAB)型PET实时低耗等效建模算法。首先,深入挖掘了DAB高频链端口解耦模型的二值输入导纳特性,并从数值分析与物理意义两个层面进行了阐述。以此为基础,构建了具有N+1特性的PET高频链端口解耦模型。其次,提出了基于有限存储的低内存占用EMT解算方案、紧凑型低延时仿真框架、分组并行流水线计算硬件实现方案,降低了所提等效模型在实时仿真中对存储内存、计算时钟和硬件资源的需求。最后,在RT-LAB中完成了基于Verilog语言的250 ns实时低耗等效仿真模型开发,并进行了所建模型仿真精度和资源利用率测试。

基于CPS和VMD的实时电力需求饱和自适应预测

电力数据具有非平稳性和随机性的特点,导致电力需求预测结果误差较大,为此,提出基于CPS和VMD的实时电力需求饱和自适应预测方法。基于CPS与VMP建立自适应变分模态分解模型,利用实时电力需求序列和各模态分解余量之间的信息散度差来判断相关性程度,实现模态分解,通过自适应模态分解得到电力需求序列的分解余量,依靠其建立自适应预测模型,并对模型进行训练,完成对实时电力需求饱和自适应预测。实验结果表明,设计方法预测结果的平均绝对误差低于5.0,平均绝对百分比误差低于2.45%。

基于RTLAB虚实结合的馈线自动化测试

针对馈线自动化的功能测试问题,为避免配电终端接入实际配电网进行测试实验可能对电力系统的安全运行造成不利影响,同时为了提高测试的灵活性、效率性和正确性,文中提出了一种虚实结合的馈线自动化测试方法,利用RTLAB(Real Time Laboratory)实时全数字仿真器搭建配电网并模拟故障运行,设计具备保护、重合闸、就地式FA(Feeder Automation)功能的仿真型虚拟配电终端用于开展RTLAB实时仿真器与物理模型硬件在环仿真研究。文中设计的基于高性能线性功率放大器的接口实施方案被测配电终端接入测试系统形成闭环,构建了虚实结合的馈线自动化仿真测试环境。通过开展基本故障处理能力测试和容错能力测试的硬件在环仿真实验,验证了接口装置的准确性,同时验证了测试平台的有效性。

分权与制衡:北宋时期国家治理的主线

北宋时期发展出一套与近代责任政府“神似”的独特治理体系,通过非成文法(祖宗法)确立下来的“习惯法”上升成了朝廷纲常——君权象征化,国家治理一旦有过失,则必问责,责任即由宰相们承担。北宋开国便确立了一系列政治原则:(1)“士大夫与皇帝共天下”实则为北宋不可变的政治惯例,“虚君实相”的治理结构使得皇权表现出高度的谦抑性;(2)责任政府让皇帝“统而不治”,治权与政权高度分离,宰相拥有较高的行政权;(3)台谏在北宋的地位极高,对行政权形成了史无前例的限制,形成了皇帝——宰相——台谏的并立局面。