Improved particle swarm optimization algorithm for multi-reservoir system operation

In this paper, a hybrid improved particle swarm optimization （IPSO） algorithm is proposed for the optimization of hydroelectric power scheduling in multi-reservoir systems. The conventional particle swarm optimization （PSO） algorithm is improved in two ways： （1） The linearly decreasing inertia weight coefficient （LDIWC） is replaced by a self-adaptive exponential inertia weight coefficient （SEIWC）, which could make the PSO algorithm more balanceable and more effective in both global and local searches. （2） The crossover and mutation idea inspired by the genetic algorithm （GA） is imported into the particle updating method to enhance the diversity of populations. The potential ability of IPSO in nonlinear numerical function optimization was first tested with three classical benchmark functions. Then, a long-term multi-reservoir system operation model based on IPSO was designed and a case study was carried out in the Minjiang Basin in China, where there is a power system consisting of 26 hydroelectric power plants. The scheduling results of the IPSO algorithm were found to outperform PSO and to be comparable with the results of the dynamic programming successive approximation （DPSA） algorithm.

Study on Independent Supervision Function of Design Assurance System

The effective operation of a design assurance system cannot be achieved without the effective performance of the independent supervision function.As one of the core functions of the design assurance system,the purpose of the independent supervision function is to ensure that the system operates within the scope of procedures and manuals.At present,the function of independent supervision is a difficult and confusing issue for various original equipment manufacturers as well as suppliers,and there is an urgent requirement to put forward relevant requirements and form relevant methods.Based on the above mentioned objective,the basic requirements of the independent supervision function of design assurance system were studied,the problems and deficiencies in the organization,staffing,and methods existing in the current independent supervision function were analyzed,the improvement suggestions and measures for the performance of the independent supervision function from the aspects of the organization,staffing,procedures,and suppliers were put forward.The present work and conclusions provide guidance and direction for the effective operation of the design assurance system.

District heating system operation in power systems with high share of wind power

The integration of continuously varying and not easily predictable wind power generation is affecting the stability of the power system and leads to increasing demand for balancing services.In this study,a short-term operation model of a district heating system is proposed to optimally schedule the production of both heat and power in a system with high wind power penetration.The application of the model in a case study system shows the increased flexibility offered by the coordination of power generation,consumption and heat storage units which are available in district heating systems.

Uncertainty Management in Power System Operation

This paper summarizes the prevailing power system operation methods for managing the uncertainty brought by large-scale integration of renewables and active load demand.From the perspective of power system operations,uncertainty management is an important problem.In this paper,the mathematical models used for handling uncertainty are discussed,along with the pros and cons as well as future development efforts of four different operation methods.The study concludes that it is difficult to adopt a universal operation theory for mitigating the uncertainty in power system operations.Instead,it is necessary to choose the most feasible operation method that matches the specific operation requirement.

Synchrophasor-based real-time state estimation and situational awareness system for power system operation

State estimation is a critical functionality of energy management system(EMS) to provide power system states in real-time operations. However, problems such as failure to converge, prone to failure during contingencies,and biased estimates while system is under stressed condition occur so that state estimation results may not be reliable.The unreliable results further impact downstream network and market applications, such as contingency analysis,voltage stability analysis, transient stability analysis, system alarming, and unit commitment. Thus, operators may lose the awareness of system condition in EMS. This paper proposes a fully independent and one-of-a-kind system by integrating linear state estimator into situational awareness applications based on real-time synchrophasor data. With guaranteed and accurate state estimation solution and advanced real-time data analytic and monitoring functionalities, the system is capable of assisting operators to assess and diagnose current system conditions for proactive and necessary corrective actions. The architecture, building components, and implementation of the proposed system are explored in detail. Two case studies with simulated data from the subsystems of Electric Reliability Council of Texas(ERCOT) and Los Angeles Department of Water and Power(LADWP) are presented. The test results show the effectiveness and reliability of the system, and its value for realtime power system operations.

Energy-Efficient Operation of Water Systems through Optimization of Load Power Reduction in Electricity Markets

Demand response(DR) is gaining more and more importance in the architecture of power systems in a context of flexible loads and high share of intermittent generation. Changes in electricity markets regulation in several countries have recently enabled an effective integration of DR mechanisms in power systems. Through its flexible components(pumps, tanks), drinking water systems are suitable candidates for energy-efficient DR mechanisms. However, these systems are often managed independently of power system operation for both economic and operational reasons. Indeed, a sufficient level of economic viability and water demands risk management are necessary for water utilities to integrate their flexibilities to power system operation. In this paper,we proposed a mathematical model for optimizing pump schedules in water systems while trading DR blocs in a spot power market during peak times. Uncertainties about water demands were considered in the mathematical model allowing to propose power reductions covering the potential risk of real-time water demand forecasting inaccuracy.Numerical results were discussed on a real water system in France, demonstrating both economic and ecological benefits.

Data-driven Probabilistic Static Security Assessment for Power System Operation Using High-order Moments

In this letter,a new formulation of Lebesgue integration is used to evaluate the probabilistic static security of power system operation with uncertain renewable energy generation.The risk of power flow solutions violating any pre-defined operation security limits is obtained by integrating a semialgebraic set composed of polynomials.With the high-order moments of historical data of renewable energy generation,the integration is reformulated as a generalized moment problem which is then relaxed to a semi-definite program(SDP).Finally,the effectiveness of the proposed method is verified by numerical examples.

Experiences of the Electricity System Operator Incentive Scheme in Great Britain

National Grid is the electricity system operator in Great Britain and has an unique feature in so far as it is one of the world’s few for-profit system operators. In addition, the commercially orientation of the British market rules means that nearly every action taken by National Grid to operate the system has a cost associated to it. Based on those factors and in order to encourage National Grid to seek continuous improvements and drive for efficient and economic system operation, the regulator (Ofgem) offers an incentive scheme, whereby a target is agreed annually and any savings in relation to this target are shared between consumers and National Grid in the form of a profit. It is in National Grid’s best interest to have mechanisms to mitigate the impacts of volatility in the costs it faces as system operator so that it can implement cost saving actions without the risk of windfall losses (or gains) arising from sudden changes in uncontrollable drivers. The purpose of this paper is to share the experiences of National Grid in the operation of Great Britain's electricity system, with a special interest on the mechanisms created to manage the associated costs in response to the incentive scheme. It does so by describing the market operation in Great Britain and the costs drivers impacting National Grid’s system operation and illustrating the steps recently taken by National Grid to propose volatility mitigation mechanisms. It concludes with the rationale and expected results from the latest proposals as consulted with the industry for introduction in the incentive scheme starting on 1st April 2011. It is worth noting that with this work, the authors wish to both share the experience with other system operators and regulators in the world, as well as give British market participants an insight on the inner workings of National Grid.

Storing Freshwater Versus Storing Electricity in Power Systems with High Freshwater Electric Demand

We consider a power system whose electric demand pertaining to freshwater production is high(high freshwater electric demand),as in the Middle East,and investigate the tradeoff of storing freshwater in tanks versus storing electricity in batteries at the day-ahead operation stage.Both storing freshwater and storing electricity increase the actual electric demand at valley hours and decrease it at peak hours,which is generally beneficial in term of cost and reliability.But,to what extent?We analyze this question considering three power systems with different generation-mix configurations,i.e.,a thermal-dominated mix,a renewable-dominated one,and a fully renewable one.These generation-mix configurations are inspired by how power systems may evolve in different countries in the Middle East.Renewable production uncertainty is compactly modeled using chance constraints.We draw conclusions on how both storage facilities(freshwater and electricity)complement each other to render an optimal operation of the power system.

Smart Grids with Intelligent Periphery:An Architecture for the Energy Internet

A future smart grid must fulfill the vision of the Energy Internet in which millions of people produce their own energy from renewables in their homes, offices, and factories and share it with each other. Electric vehicles and local energy storage will be widely deployed. Internet technology will be utilized to transform the power grid into an energysharing inter-grid. To prepare for the future, a smart grid with intelligent periphery, or smart GRIP, is proposed. The building blocks of GRIP architecture are called clusters and include an energy-management system （EMS）-controlled transmission grid in the core and distribution grids, micro-grids, and smart buildings and homes on the periphery; all of which are hierarchically structured. The layered architecture of GRIP allows a seamless transition from the present to the future and plug-and-play interoperability. The basic functions of a cluster consist of （1） dispatch, （2） smoothing, and （3） mitigation. A risk-limiting dispatch methodology is presented; a new device, called the electric spring, is developed for smoothing out fluctuations in periphery clusters; and means to mitigate failures are discussed.

新一代银行综合业务系统全面解决方案

该文全面论述了银行综合业务管理系统，即新一代银行综合业务系统的发展及其特征，在此基础上阐述了设计目标、软硬件平台设计、应用系统的设计与实现，具有较好的可操作性和应用参考性。

韩国工程教育的现状与机遇

韩国工程教育要努力走向以消费者为主的教育体系 ,更适应社会的需要 ,建立与经济社会的各个领域紧密联系的改革系统。本文从宏观上具体探讨了当今韩国工程教育发展中面临的主要突出问题 :技术经营化课程、产学研管相互之间的合作体系、女工科学生的积极支持政策。

快速响应卫星载荷体系化建设思路

美国的快速响应空间计划通过体系路线的发展方式已取得了系列研究突破,为我国开展快速响应空间研究提供了借鉴。为实现快速响应的需求,卫星载荷在设计思路、研发模式等方面必须转变。依据体系结构设计的3个视角,分别从快速响应卫星载荷的作战需求、系统设计和技术发展三方面提出了建设思路,并预期了载荷按体系化思路建设的快速响应效果,各阶段的时间周期均可减少50%以上。

基于快响空间的地面控制系统设计

结合虚拟任务操作中心思想,提出了构建快响空间地面控制系统的初步设计方案;其方法是融合快响空间任务控制流程和业务应用流程,以"快"为核,以"服务化"云架构为基,构建面向服务的快响空间地面控制系统;最后指出,通过采用虚拟任务操作中心技术,探索了天基信息快速支援地面技术体制创新;通过采用云服务架构及天地安全互联技术,实现用户终端以调用服务的方式远程快速使用资源;通过重构快响空间地面控制流程,实现快响力量的统一控制,协同快速反应;通过采用微服务+容器架构实现任务规划、调度和控制功能的快速构建。

天基快速响应体系概念研究

为了有效增强现有空间系统应对突发事件的能力,提出了一种基于在轨发射的天基快速响应体系,分析其应用领域和作用过程,明确该体系的特点、组成要素及关键技术,包括适合的在轨发射方案和基于任务的最佳部署策略等。天基快速响应体系由航天器平台、空间运载器、有效载荷和地面基础设施组成,利用空间运载器携带有效载荷实现机动和变轨。文章提出的快速响应体系,面向未来空间在轨服务,有助于增强空间系统在自然故障、突发事件等不确定情况下的快速响应和有效部署能力。

基于工作过程的课程体系构建——石家庄职业技术学院建筑工程技术专业群专业教学改革实践

建筑工程技术专业群结合毕业生职业岗位群的需要,在建筑工程技术专业进行了基于工作过程的课程体系开发,这种课程体系注重培养学生的职业能力.分析了此课程体系构建的理念及方法,在构建新课程体系时,要对典型工作任务进行分析,对传统学科体系的课程进行解构与重构,从而构建符合工作过程的课程内容及课程实施方案.

“软件星”在快速响应空间中的应用

天基信息系统在战场感知、指挥控制与决策等方面作用日益显著。空间快速响应是天基信息系统发展的重要需求。文章介绍了"软件星"有效载荷的设计技术原理和系统基本组成,分析了其可重构多功能综合一体化设计特点,阐述了采用统一软硬件体系结构形成标准化模块化的多功能集成载荷系统是满足应急作战快速反应的基本要求,提供了一种基于"软件星"多功能任务载荷平台来实现快速响应卫星的通用设计途径,对发展快速响应空间技术具有重要参考价值。

太空快速响应发射场能力建设

为实现战争行动和突发事件的快速响应目的,太空快速响应发射已成为重要的解决手段。总结传统航天发射场面临的挑战,分析了太空快速响应活动对航天发射场的需求,从发射场建设需求体系、发射场测试能力推进、发射场改造和补充建设、天地一体测控通信体系、快速机动发射模式等提出了发射场建设发展途径,为满足太空快速响应发射场系统建设提供有益的技术参考。

美军虚拟任务作战中心走向实战

随着2011年ORS-1和TacSat-4的发射,美军虚拟任务作战中心(VMOC)开始运行,它目前正在执行的是飞行操控和情报、监视与侦察(ISR)卫星及通信卫星(SATCOM)的任务规划。介绍了VMOC的系统组成、各个子系统功能及其主要应用软件,探讨了VMOC在ORS-1和TacSat-4试验任务中发挥的作用,描述了虚拟任务作战中心的未来发展趋势。

A Scenario-classification Hybrid-based Banding Method for Power Transfer Limits of Critical Inter-corridors

To secure power system operations,practical dispatches in industries place a steady power transfer limit on critical inter-corridors,rather than high-dimensional and strong nonlinear stability constraints.However,computational complexities lead to over-conservative pre-settings of transfer limit,which further induce undesirable and non-technical congestion of power transfer.To conquer this barrier,a scenario-classification hybrid-based banding method is proposed.A cluster technique is adopted to separate similarities from historical and generated operating condition dataset.With a practical rule,transfer limits are approximated for each operating cluster.Then,toward an interpretable online transfer limit decision,costsensitive learning is applied to identify cluster affiliation to assign a transfer limit for a given operation.In this stage,critical variables that affect the transfer limit are also picked out via mean impact value.This enables us to construct low-complexity and dispatcher-friendly rules for fast determination of transfer limit.The numerical case studies on the IEEE 39-bus system and a real-world regional power system in China illustrate the effectiveness and conservativeness of the proposed method.