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Pure State Feedback Switching Control Based on the Online Estimated State for Stochastic Open Quantum Systems
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作者 Shuang Cong Zhixiang Dong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2166-2178,共13页
For the n-qubit stochastic open quantum systems,based on the Lyapunov stability theorem and LaSalle’s invariant set principle,a pure state switching control based on on-line estimated state feedback(short for OQST-SF... For the n-qubit stochastic open quantum systems,based on the Lyapunov stability theorem and LaSalle’s invariant set principle,a pure state switching control based on on-line estimated state feedback(short for OQST-SFC)is proposed to realize the state transition the pure state of the target state including eigenstate and superposition state.The proposed switching control consists of a constant control and a control law designed based on the Lyapunov method,in which the Lyapunov function is the state distance of the system.The constant control is used to drive the system state from an initial state to the convergence domain only containing the target state,and a Lyapunov-based control is used to make the state enter the convergence domain and then continue to converge to the target state.At the same time,the continuous weak measurement of quantum system and the quantum state tomography method based on the on-line alternating direction multiplier(QST-OADM)are used to obtain the system information and estimate the quantum state which is used as the input of the quantum system controller.Then,the pure state feedback switching control method based on the on-line estimated state feedback is realized in an n-qubit stochastic open quantum system.The complete derivation process of n-qubit QST-OADM algorithm is given;Through strict theoretical proof and analysis,the convergence conditions to ensure any initial state of the quantum system to converge the target pure state are given.The proposed control method is applied to a 2-qubit stochastic open quantum system for numerical simulation experiments.Four possible different position cases between the initial estimated state and that of the controlled system are studied and discussed,and the performances of the state transition under the corresponding cases are analyzed. 展开更多
关键词 online state estimation state feedback control stochastic open quantum systems(OQST) switching control
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Local Partial Least Squares Based Online Soft Sensing Method for Multi-output Processes with Adaptive Process States Division 被引量:3
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作者 邵伟明 田学民 王平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期828-836,共9页
Local learning based soft sensing methods succeed in coping with time-varying characteristics of processes as well as nonlinearities in industrial plants. In this paper, a local partial least squares based soft sensin... Local learning based soft sensing methods succeed in coping with time-varying characteristics of processes as well as nonlinearities in industrial plants. In this paper, a local partial least squares based soft sensing method for multi-output processes is proposed to accomplish process states division and local model adaptation,which are two key steps in development of local learning based soft sensors. An adaptive way of partitioning process states without redundancy is proposed based on F-test, where unique local time regions are extracted.Subsequently, a novel anti-over-fitting criterion is proposed for online local model adaptation which simultaneously considers the relationship between process variables and the information in labeled and unlabeled samples. Case study is carried out on two chemical processes and simulation results illustrate the superiorities of the proposed method from several aspects. 展开更多
关键词 Local learning online soft sensing Partial least squares F-TEST Multi-output process Process state division
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Online Maximum Loadability Monitoring Scheme for Smart Grid 被引量:1
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作者 Heng-Yi Su Yi-Chung Chen Jia-Chuan Lin 《Journal of Power and Energy Engineering》 2015年第4期170-177,共8页
This paper presents an algorithm based on Thevenin equivalent network for voltage stability evaluation. The proposed algorithm provides a technique for online predicting the largest possible margin to voltage collapse... This paper presents an algorithm based on Thevenin equivalent network for voltage stability evaluation. The proposed algorithm provides a technique for online predicting the largest possible margin to voltage collapse of an electrical power system. An online maximum loadability determination algorithm is developed by transforming the impedance margin, obtained from the Thevenin equivalent network, into the loading margin at each of the load buses in a power system. Furthermore, the proposed algorithm also takes system load trends into account for practical applications. The effectiveness of the proposed algorithm is tested on the IEEE 14 and 57 bus test systems. Simulation results have shown that the proposed algorithm is useful and practical for online voltage instability monitoring. 展开更多
关键词 MAXIMUM Lodability online MONITORING Smart grid Thevenin EQUIVALENT VOLTAGE Stability
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Online Silk Road Promotes Economic Cooperation Between China and the Arab States
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作者 Audrey Guo 《China's Foreign Trade》 2017年第6期34-35,共2页
According to the 13th Five-year National Informatization Plan issued by the State Council, it is important to establish an online silk road. The "online silk road" is a network- based information economic belt estab... According to the 13th Five-year National Informatization Plan issued by the State Council, it is important to establish an online silk road. The "online silk road" is a network- based information economic belt established by China and countries along the Belt and Road, 展开更多
关键词 online Silk Road Economic Cooperation Between China the Arab states
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Forecasting-Based Adaptive Optimized Dispatch in Smart Grid Online
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作者 Qiang Jiang Dan Hu Duyi He 《International Journal of Modern Nonlinear Theory and Application》 2020年第1期1-18,共18页
The power grid is a fusion of technologies in energy systems, and how to adjust and control the output power of each generator to balance the load of the grid is a crucial issue. As a platform, the smart grid is for t... The power grid is a fusion of technologies in energy systems, and how to adjust and control the output power of each generator to balance the load of the grid is a crucial issue. As a platform, the smart grid is for the convenience of the implementation of adaptive control generators using advanced technologies. In this paper, we are introducing a new approach, the Central Lower Configuration Table, which optimizes dispatch of the generating capacity in a smart grid power system. The dispatch strategy of each generator in the grid is presented in the configuration table, and the scenario consists of two-level agents. A central agent optimizes dispatch calculation to get the configuration table, and a lower agent controls generators according to the tasks of the central level and the work states during generation. The central level is major optimization and adjustment. We used machine learning to predict the power load and address the best optimize cost function to deal with a different control strategy. We designed the items of the cost function, such as operations, maintenances and the effects on the environment. Then, according to the total cost, we got a new second-rank-sort table. As a result, we can resolve generator’s task based on the table, which can also be updated on-line based on the environmental situation. The signs of the driving generator’s controller include active power and system’s f. The lower control level agent carries out the generator control to track f along with the best optimized cost function. Our approach makes optimized dispatch algorithm more convenient to realize, and the numerical simulation indicates the strategy of machine learning forecast of optimized power dispatch is effective. 展开更多
关键词 MACHINE Learning SMART grid ADAPTIVE Control DISPATCH Power online
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一种改进的网格多边形online探索算法 被引量:1
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作者 谢玉莹 包敏泽 +1 位作者 胡秀婷 蒋波 《计算机应用与软件》 北大核心 2022年第3期218-222,315,共6页
针对网格多边形机器人online探索问题,在分析现有成果的基础上,结合SmartDFS算法,并通过扩大机器人视觉范围,使其范围限定在给定的单位网格内。通过区分不同类型的网格,确定遍历的优先级别以设计出不同的探索策略,提出SmartDFS-OPT算法... 针对网格多边形机器人online探索问题,在分析现有成果的基础上,结合SmartDFS算法,并通过扩大机器人视觉范围,使其范围限定在给定的单位网格内。通过区分不同类型的网格,确定遍历的优先级别以设计出不同的探索策略,提出SmartDFS-OPT算法。该算法将网格多边形online探索问题求解算法的竞争比从5/4降低为7/6,达到了理论分析结果的下界,使机器人的online遍历路径长度达到最短,因而是求解该问题的一个最优算法。该算法将有助于那些基于机器人探索未知环境的智能设备的研发与应用。 展开更多
关键词 计算几何 网格多边形 online探索 可视范围最大化 竞争比
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Teaching Model Integrating Online and Offline in Real Time ——An Exploration of New Teaching Mode for Regular Epidemic Prevention and Control 被引量:1
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作者 Ce Zhang Yongyuan Jiang +1 位作者 Peng Liu Meng Wei 《计算机教育》 2022年第12期106-113,共8页
During epidemic,students in medium-risk or high-risk areas are unable to return to school on time.In response to this new challenge,there is an urgent need to create a new teaching mode to offer on-line courses to tho... During epidemic,students in medium-risk or high-risk areas are unable to return to school on time.In response to this new challenge,there is an urgent need to create a new teaching mode to offer on-line courses to those absent from the offline classes,and we propose a model integrating online and offline teaching.It is based on“dual-camera”method,which allows off-campus students to virtually build up a physical classroom scenario on campus through computers and mobile phones.Using this model,students can participate in class remotely.In order to enhance the engagement of off-campus online students,emphasis is placed on interactive teaching.Teachers are required to design their teaching in advance and to work in collaboration with multiple departments,then using information technology and suitable teaching methods to enable students to participate in physical classroom teaching.This model has been tested in practice and has been successful in meeting the challenges.Finally,4 areas for improvement and refinement are identified. 展开更多
关键词 Epidemic prevention and control New normal state MOOC online and offline integrated teaching model
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Mathematical methods for main tenance and operation cost prediction based on transfer learning in State Grid
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作者 GUO Yun-peng WANG Dong-fa +1 位作者 ZHENG Ying DING Wei-bin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第4期598-614,共17页
The electric power enterprise is an important basic energy industry for national development,and it is also the first basic industry of the national economy.With the continuous expansion of State Grid,the progressivel... The electric power enterprise is an important basic energy industry for national development,and it is also the first basic industry of the national economy.With the continuous expansion of State Grid,the progressively complex operating conditions,and the increasing scope and frequency of data collection,how to make reasonable use of electrical big data,improve utilization,and provide a theoretical basis for the reliability of State Grid operation,has become a new research hot spot.Since electrical data has the characteristics of large volume,multiple types,low-value density,and fast processing speed,it is a challenge to mine and analyze it deeply,extract valuable information efficiently,and serve for the actual problem.According to the features of these data,this paper uses artificial intelligence methods such as time series and support vector regression to establish a data mining network model for standard cost prediction through transfer learning.The experimental results show that the model in this paper obtains better prediction results on a small sample data set,which verifies the feasibility of the deep transfer model.Compared with activity-based costing and the traditional prediction method,the average absolute error of the proposed method is reduced by 10%,which is effective and superior. 展开更多
关键词 transfer learning LSTM support vector regression activity based costing state grid
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Power Control Based on State Space Strategies for Grid⁃Oriented Inverters with LCL Filters
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作者 Chunyu Lu Wei Hua Mingjin Hu 《Journal of Harbin Institute of Technology(New Series)》 CAS 2022年第2期1-12,共12页
Through a third⁃order mathematical model of grid⁃oriented LCL⁃type converters,this paper analyzes the complicated dynamic characteristics and resonance problems which may influence the system stability.To realize acti... Through a third⁃order mathematical model of grid⁃oriented LCL⁃type converters,this paper analyzes the complicated dynamic characteristics and resonance problems which may influence the system stability.To realize active damping for LCL filters and improve dynamic performance of current regulators,a state space current PI controller is proposed whose parameters can be tuned based on the polynomial equations approach.An extended state observer is integrated with the regulation scheme,where additional sensors are not necessary in contrast with conventional active damping strategies.Synchronous reference frame PLL(SRF⁃PLL)equipped with filter technology is proposed for grid voltage disturbance suppression.This method is then applied to establish a double⁃closed⁃loop power regulator that demonstrates improved performance compared with other controllers.The simulation results are displayed to illustrate the efficiency of the regulation methods. 展开更多
关键词 LCL⁃type grid⁃oriented converters state space current control SRF⁃PLL closed loop power control
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Assessment on Fault Diagnosis and State Evaluation of New Power Grid:AReview
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作者 Bo Yang Yulin Li +3 位作者 Yaxing Ren Yixuan Chen Xiaoshun Zhang Jingbo Wang 《Energy Engineering》 EI 2023年第6期1287-1293,共7页
1 Introduction The proposal of the concept of“New Power System”aims to illustrate the transform direction of the traditional power system,acting as the development core of the future new power grid.To achieve this,t... 1 Introduction The proposal of the concept of“New Power System”aims to illustrate the transform direction of the traditional power system,acting as the development core of the future new power grid.To achieve this,the proposed strategic targets of“carbon neutralization and carbon peaking”must be implemented and insisted[1].The core feature of the new power system is that renewable energy plays a leading role and becomes the main source of energy supply,meanwhile,the goal of green energy utilization has also been put forward on the agenda.Green energy utilization includes two aspects,one is the exploitation and promotion of various green energy technologies,and the other is the digitalization of energy management.Under this trend,stochastic and fluctuating energy sources such as wind power and photovoltaic power replace deterministic controllable power sources such as thermal power,bringing challenges to power grid regulation and dispatching,as well as flexible operation.The large-scale integration of renewable energy and increasingly high proportion of power electronic equipment tend to bring about fundamental changes in the operation characteristics,safety control,and production mode of the power system. 展开更多
关键词 Carbon neutrality and carbon peak goals renewable energy fault diagnosis state evaluation new power grid
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The State Power Grid Development Ltd Corp. officially established
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《Electricity》 1996年第3期26-26,共1页
The establishment of the State Power Grid Development Corp Ltd(SPG) was officially announced on June 18, marking the government’s determination to form a nationwide united power network to make the best of power gene... The establishment of the State Power Grid Development Corp Ltd(SPG) was officially announced on June 18, marking the government’s determination to form a nationwide united power network to make the best of power generating capability. The State-owned corporation, with 2.5 billion yuan ($301 million) worth of operating capital raised by the government, will be responsible for investment. construction and management of the power transmission and substation projects involved in the construction of the Three Gorges Project. 展开更多
关键词 grid officially established The state Power grid Development Ltd Corp
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Control Strategy of Grid-connected Converters With LCL Filter Based on Discrete State-space Model
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《中国电机工程学报》 EI CSCD 北大核心 2011年第36期I0002-I0002,共1页
关键词 状态空间模型 滤波器 控制策略 连接 电网 转换器 离散 主动阻尼
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State Grid Contributes to Clean Energy Development
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作者 Zhao Qingbo State Grid Corporation of China Zhang Sufang 《Electricity》 2010年第3期48-50,共3页
The development of clean energy is an inevitable choice for China to achieve sustainable development.The article presents the strategic thinking and measures for the promotion of clean energy development in grids,whic... The development of clean energy is an inevitable choice for China to achieve sustainable development.The article presents the strategic thinking and measures for the promotion of clean energy development in grids,which shows that the company will bear its responsibilities for the development as a large state-owned enterprise. 展开更多
关键词 clean energy state grid energy strategy
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Micro-Grid Smooth Switchover Method Based on Controller State Following
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作者 Yang Fu Lisha Huang Jingjing Zhao 《Journal of Power and Energy Engineering》 2015年第4期128-135,共8页
Micro-grid smooth switchover between different operation modes is important for steady operation and reliable power supply of micro-grid. In order to reduce the transient fluctuation of voltage and frequency during sw... Micro-grid smooth switchover between different operation modes is important for steady operation and reliable power supply of micro-grid. In order to reduce the transient fluctuation of voltage and frequency during switchover, this paper proposed a new switchover method based on controller state following. When transferring to island mode, the control method for inverter of storage device changed from PQ control to V/f control. Before switchover, the output of V/f controller is always following the output of PQ controller. So that the sudden change of output is avoided at the moment of switchover. A micro-grid model with photovoltaic and battery is built on DIgSILENT Power Factory simulation software, to simulate micro-grid switchover from grid-connected mode to island mode. Results show this method can effectively suppress the transient fluctuation of voltage and frequency, and reduce the influence of transient process on power grid. This conclusion has important practical significance on micro-grid smooth switchover from grid-con- nected mode to island mode. 展开更多
关键词 MICRO-grid SMOOTH Switchover CONTROLLER state FOLLOWING
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Fortifying Smart Grids: A Holistic Assessment Strategy against Cyber Attacks and Physical Threats for Intelligent Electronic Devices
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作者 Yangrong Chen June Li +4 位作者 Yu Xia Ruiwen Zhang Lingling Li Xiaoyu Li Lin Ge 《Computers, Materials & Continua》 SCIE EI 2024年第8期2579-2609,共31页
Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control instructions.In the context of the heightene... Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control instructions.In the context of the heightened security challenges within smart grids,IEDs pose significant risks due to inherent hardware and software vulner-abilities,as well as the openness and vulnerability of communication protocols.Smart grid security,distinct from traditional internet security,mainly relies on monitoring network security events at the platform layer,lacking an effective assessment mechanism for IEDs.Hence,we incorporate considerations for both cyber-attacks and physical faults,presenting security assessment indicators and methods specifically tailored for IEDs.Initially,we outline the security monitoring technology for IEDs,considering the necessary data sources for their security assessment.Subsequently,we classify IEDs and establish a comprehensive security monitoring index system,incorporating factors such as running states,network traffic,and abnormal behaviors.This index system contains 18 indicators in 3 categories.Additionally,we elucidate quantitative methods for various indicators and propose a hybrid security assessment method known as GRCW-hybrid,combining grey relational analysis(GRA),analytic hierarchy process(AHP),and entropy weight method(EWM).According to the proposed assessment method,the security risk level of IEDs can be graded into 6 levels,namely 0,1,2,3,4,and 5.The higher the level,the greater the security risk.Finally,we assess and simulate 15 scenarios in 3 categories,which are based on monitoring indicators and real-world situations encountered by IEDs.The results show that calculated security risk level based on the proposed assessment method are consistent with actual simulation.Thus,the reasonableness and effectiveness of the proposed index system and assessment method are validated. 展开更多
关键词 Smart grid intelligent electronic device security assessment abnormal behaviors network traffic running states
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Steady-State Analysis of Grid-Connected New Energy Power Plants
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作者 Zhichao Zhang 《Journal of Architectural Research and Development》 2023年第2期64-71,共8页
In order to ease the fossil energy crunch,new energy sources need to be fully utilized.Clean energy sources such as wind,light,and nuclear energy are important tools to solve environmental and energy problems.However,... In order to ease the fossil energy crunch,new energy sources need to be fully utilized.Clean energy sources such as wind,light,and nuclear energy are important tools to solve environmental and energy problems.However,in the process of researching new energy farms,there are some problems when they are integrated into the power system.In order to ensure the stability of new energy power plants,it is necessary to conduct an in-depth analysis of the grid connection technology of new energy farms.In the study,it is necessary to learn about the specific problems of the stability of the grid connection of new energy power plants,and to clarify the specific application of the grid connection technology of new energy power plants from the application principle and advantages of the grid connection technology of new energy power plants.Through simulation experiments,the positive effect of grid connection technology of new energy power plants in improving the stability of power systems was determined. 展开更多
关键词 New energy power plant grid connection technology online publication:March 31 2023
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Web服务与Grid服务之比较研究 被引量:4
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作者 尹皓 周激流 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2004年第6期1284-1286,共3页
With the combination of grid technology and Web services, the concept of Grid service arises for such purposes as service discovery, creation of dynamic services, lifecycle management and so forth. Authors compares th... With the combination of grid technology and Web services, the concept of Grid service arises for such purposes as service discovery, creation of dynamic services, lifecycle management and so forth. Authors compares the Web service with Grid service in respect of programming design, and states the characteristics of Grid service. 展开更多
关键词 WEB服务 OGSA 网格服务 grid技术 网格环境 体系结构 程序设计 生命周期管理 动态 创建
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Remaining Useful Life Model and Assessment of Mechanical Products: A Brief Review and a Note on the State Space Model Method 被引量:9
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作者 Yawei Hu Shujie Liu +1 位作者 Huitian Lu Hongchao Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第1期11-30,共20页
The remaining useful life(RUL) prediction of mechanical products has been widely studied for online system performance reliability, device remanufacturing, and product safety(safety awareness and safety improvement). ... The remaining useful life(RUL) prediction of mechanical products has been widely studied for online system performance reliability, device remanufacturing, and product safety(safety awareness and safety improvement). These studies incorporated many di erent models, algorithms, and techniques for modeling and assessment. In this paper, methods of RUL assessment are summarized and expounded upon using two major methods: physics model based and data driven based methods. The advantages and disadvantages of each of these methods are deliberated and compared as well. Due to the intricacy of failure mechanism in system, and di culty in physics degradation observation, RUL assessment based on observations of performance variables turns into a science in evaluating the degradation. A modeling method from control systems, the state space model(SSM), as a first order hidden Markov, is presented. In the context of non-linear and non-Gaussian systems, the SSM methodology is capable of performing remaining life assessment by using Bayesian estimation(sequential Monte Carlo). Being e ective for non-linear and non-Gaussian dynamics, the methodology can perform the assessment recursively online for applications in CBM(condition based maintenance), PHM(prognostics and health management), remanufacturing, and system performance reliability. Finally, the discussion raises concerns regarding online sensing data for SSM modeling and assessment of RUL. 展开更多
关键词 REMAINING useful life state space MODEL online ASSESSMENT BAYESIAN estimation Particle filter REMANUFACTURING
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Three-defense Line Coordination Strategy of the Guizhou Power Grid with the New Security Situation
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作者 Wencheng Zheng Tao Yu 《Energy and Power Engineering》 2013年第3期36-41,共6页
In order to meet the requirements of Decree of the State Council of the People's Republic of China (No.599), this paper presents a three-defense line coordination strategy based on the Decree of the State Council ... In order to meet the requirements of Decree of the State Council of the People's Republic of China (No.599), this paper presents a three-defense line coordination strategy based on the Decree of the State Council (No.599). Taking the Guizhou power grid of 220 kV&500 kV as an example, the security and stability problem of the Guizhou power grid is analyzed. The strategy using three-defense line coordination for lowering the level of electricity safety accidents is researched. The analysis results show that the proposed coordination strategy is feasible, which can lower the level of electricity safety accidents under the same fault in same operation mode. Through studying the three-defense line of the Guizhou power grid, this paper presents a basic idea of the three-defense line coordination strategy based on the Decree of the State Council (No.599). The three-defense line coordination strategy provides reference for other provinces power grid. 展开更多
关键词 Security and Stability Three-defense LINE the GUIZHOU Power grid Decree of the state COUNCIL (No.599)
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电力系统在线安全稳定计算分析技术综述与展望
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作者 韩英铎 陆超 +3 位作者 宋文超 吴沛萱 方浩男 刘维承 《中国电机工程学报》 EI CSCD 北大核心 2024年第17期6733-6760,I0005,共29页
在线安全稳定计算分析技术是电力调度部门准确感知电网实时运行状态并做出正确评估决策的重要支撑。随着新型电力系统动态特性愈发复杂与随机,以稳态、非同步量测数据为基础的传统在线安全稳定分析体系逐渐表现出实时性和准确性上的不足... 在线安全稳定计算分析技术是电力调度部门准确感知电网实时运行状态并做出正确评估决策的重要支撑。随着新型电力系统动态特性愈发复杂与随机,以稳态、非同步量测数据为基础的传统在线安全稳定分析体系逐渐表现出实时性和准确性上的不足,而以动态、同步相量量测数据为基础的新一代在线安全稳定分析技术愈发受到国内外相关科研及工程领域的关注。基于此,该文就实时状态感知、动态参数辨识和在线稳定评估3个核心组成部分对现有在线安全稳定计算分析体系所涉及的关键技术及瓶颈难题进行综述,并进一步提出新一代在线安全稳定计算分析技术的总体框架和未来研究方向,以期为新型电力系统安全稳定运行提供可靠技术保障。 展开更多
关键词 安全稳定计算 实时状态感知 动态参数辨识 在线稳定评估
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