Cyber-physical electrical energy systems(CPEES)combine computation,communication and control technologies with physical power system,and realize the efficient fusion of power,information and control.This paper summari...Cyber-physical electrical energy systems(CPEES)combine computation,communication and control technologies with physical power system,and realize the efficient fusion of power,information and control.This paper summarizes and analyzes related critical scientific problems and technologies,which are needed to be addressed with the development of CPEES.Firstly,since the co-simulation is an effective method to investigate infrastructure interdependencies,the co-simulation platform establishment of CPEES and its evaluation is overviewed.Then,a critical problem of CPEES is the interaction between energy and information flow,especially the influence of failures happening in information communication technology(ICT)on power system.In order to figure it out,the interaction is analyzed and the current analysis methods are summarized.For the solution of power system control and protection in information network environment,this paper outlines different control principles and illustrates the concept of distributed coordination control.Moreover,mass data processing and cluster analysis,architecture of communication network,information transmission technology and security of CPEES are summarized and analyzed.By solving the above problems and technologies,the development of CPEES will be significantly promoted.展开更多
作为电气安全的重要手段之一,接地网在建筑中扮演了重要且必不可少的角色。在现实建筑设计中,接地网的设计和建筑本身的设计被分割为两个独立和割裂的设计过程。割裂的设计过程使得接地网的设计常常无法充分考虑建筑的特殊需求,特别是...作为电气安全的重要手段之一,接地网在建筑中扮演了重要且必不可少的角色。在现实建筑设计中,接地网的设计和建筑本身的设计被分割为两个独立和割裂的设计过程。割裂的设计过程使得接地网的设计常常无法充分考虑建筑的特殊需求,特别是新能源建筑如一体化光伏建筑带来的新的需求。提出一个基于建筑信息模型（building information model,BIM）的建筑接地网统一设计平台,在BIM平台实现了对接地网的设计、计算的一体化服务。构建了基于BIM模型的接地网相关的设备模型,充分利用基于BIM的建筑3D模型、电气设备信息、线路模型来精确地计算系统最大短路电流。在此基础上,通过获取的建筑接地网的信息和土壤模型,实现了基于有限元算法的接地网计算,计算结果直接以3D形式呈现在建筑信息模型中。该平台已经应用在一个光伏建筑的接地网设计中,获得了较好的效果。展开更多
In the recent decade,a significant increase in the penetration level of renewable energy sources(RESs)into the distribution grid is evident due to the world’s shift towards clean energy and to increase the reliabilit...In the recent decade,a significant increase in the penetration level of renewable energy sources(RESs)into the distribution grid is evident due to the world’s shift towards clean energy and to increase the reliability or inboard manner resiliency of electrical distribution system.RES based microgrids are the most favorable option available,especially to enhance resiliency.However,the integration of RES over the distribution grid would hamper the grid stability due to its stochastic nature under normal conditions.During extreme weather conditions,RES behavior is completely uncertain.Hence there is a need to eliminate the adverse effects caused by the RES and make the distribution grid more reliable and stable under normal and resilient conditions.To address these issues,many researchers proposed several methods to place energy storage units(ESUs)and microgrids(RES integrated),which can support critical loads at an optimal location in the distribution system during normal and extreme conditions,respectively.The aim of this article is to consolidate and review the research towards various approaches to formulate the problem(optimal location,allocation,and operation of ESU and microgrids to face regular and extreme weather condition)and tools to solve it for enhanced system flexibility and resiliency.Based on the review,a generalized methodology has been designed to adapt the inputs and address both conditions.At the end of the review,future aspects for ESU to strengthen resistance and resiliency of its own are presented,which can be helpful to further improve the reliability and resiliency of the distribution system.展开更多
When a line failure occurs in a power grid, a load transfer is implemented to reconfigure the network by changingthe states of tie-switches and load demands. Computation speed is one of the major performance indicator...When a line failure occurs in a power grid, a load transfer is implemented to reconfigure the network by changingthe states of tie-switches and load demands. Computation speed is one of the major performance indicators inpower grid load transfer, as a fast load transfer model can greatly reduce the economic loss of post-fault powergrids. In this study, a reinforcement learning method is developed based on a deep deterministic policy gradient.The tedious training process of the reinforcement learning model can be conducted offline, so the model showssatisfactory performance in real-time operation, indicating that it is suitable for fast load transfer. Consideringthat the reinforcement learning model performs poorly in satisfying safety constraints, a safe action-correctionframework is proposed to modify the learning model. In the framework, the action of load shedding is correctedaccording to sensitivity analysis results under a small discrete increment so as to match the constraints of line flowlimits. The results of case studies indicate that the proposed method is practical for fast and safe power grid loadtransfer.展开更多
Electrolysers,which convert electricity into hydrogen,have the potential to offer a variety of electrical-grid services,therefore facilitating the integration of intermittent renewables into electrical grids.Among var...Electrolysers,which convert electricity into hydrogen,have the potential to offer a variety of electrical-grid services,therefore facilitating the integration of intermittent renewables into electrical grids.Among various activities that aim to unlock this hidden value,the 3-year European Union project QualyGridS launched in 2017 aims to establish standardized testing protocols for electrolysers to perform electricity-grid services.This paper shares experience and intermediate results of QualyGridS with respect to the testing protocols,test benches and testing results.The results of this work facilitate mutual understanding between the electricity industry and the hydrogen industry,support further development of the cross-sector testing standards,guide the design and selection of grid-service-oriented electrolyser applications and foster the transition towards a fossil-free-energy future based on high shares of hydrogen and other renewable solutions.展开更多
Due to the increasing share of renewable energy, new requirements are placed on control room software. Such software is often exclusive to the supplier, but other suppliers could offer new and better methods. For secu...Due to the increasing share of renewable energy, new requirements are placed on control room software. Such software is often exclusive to the supplier, but other suppliers could offer new and better methods. For security reasons, external applications often have no direct data access to control room software. Such software can provide information about the power grid via a periodic file transfer in CIM (Common Information Model) format. These files are often very large, containing complete records, delivering information not always relevant to the external applications. Extracting the relevant information required by external applications can be time-consuming, thus presenting a problem for time-critical applications. This paper presents a method allowing different applications to efficiently access the relevant data from the massive data stream contained in the CIM files. This method has been tested with a distribution system operator and clearly increases performance, allowing different applications to access the relevant data.展开更多
基金supported by the national Natural Science Foundation of China(NSFC)under Grant 61233008 and 51377001by the International Science and Technology Cooperation Program of China under Grant 2015DFA70580by the State Grid Science and Technology Project of China under Grant 5216A213509X.
文摘Cyber-physical electrical energy systems(CPEES)combine computation,communication and control technologies with physical power system,and realize the efficient fusion of power,information and control.This paper summarizes and analyzes related critical scientific problems and technologies,which are needed to be addressed with the development of CPEES.Firstly,since the co-simulation is an effective method to investigate infrastructure interdependencies,the co-simulation platform establishment of CPEES and its evaluation is overviewed.Then,a critical problem of CPEES is the interaction between energy and information flow,especially the influence of failures happening in information communication technology(ICT)on power system.In order to figure it out,the interaction is analyzed and the current analysis methods are summarized.For the solution of power system control and protection in information network environment,this paper outlines different control principles and illustrates the concept of distributed coordination control.Moreover,mass data processing and cluster analysis,architecture of communication network,information transmission technology and security of CPEES are summarized and analyzed.By solving the above problems and technologies,the development of CPEES will be significantly promoted.
文摘作为电气安全的重要手段之一,接地网在建筑中扮演了重要且必不可少的角色。在现实建筑设计中,接地网的设计和建筑本身的设计被分割为两个独立和割裂的设计过程。割裂的设计过程使得接地网的设计常常无法充分考虑建筑的特殊需求,特别是新能源建筑如一体化光伏建筑带来的新的需求。提出一个基于建筑信息模型（building information model,BIM）的建筑接地网统一设计平台,在BIM平台实现了对接地网的设计、计算的一体化服务。构建了基于BIM模型的接地网相关的设备模型,充分利用基于BIM的建筑3D模型、电气设备信息、线路模型来精确地计算系统最大短路电流。在此基础上,通过获取的建筑接地网的信息和土壤模型,实现了基于有限元算法的接地网计算,计算结果直接以3D形式呈现在建筑信息模型中。该平台已经应用在一个光伏建筑的接地网设计中,获得了较好的效果。
文摘In the recent decade,a significant increase in the penetration level of renewable energy sources(RESs)into the distribution grid is evident due to the world’s shift towards clean energy and to increase the reliability or inboard manner resiliency of electrical distribution system.RES based microgrids are the most favorable option available,especially to enhance resiliency.However,the integration of RES over the distribution grid would hamper the grid stability due to its stochastic nature under normal conditions.During extreme weather conditions,RES behavior is completely uncertain.Hence there is a need to eliminate the adverse effects caused by the RES and make the distribution grid more reliable and stable under normal and resilient conditions.To address these issues,many researchers proposed several methods to place energy storage units(ESUs)and microgrids(RES integrated),which can support critical loads at an optimal location in the distribution system during normal and extreme conditions,respectively.The aim of this article is to consolidate and review the research towards various approaches to formulate the problem(optimal location,allocation,and operation of ESU and microgrids to face regular and extreme weather condition)and tools to solve it for enhanced system flexibility and resiliency.Based on the review,a generalized methodology has been designed to adapt the inputs and address both conditions.At the end of the review,future aspects for ESU to strengthen resistance and resiliency of its own are presented,which can be helpful to further improve the reliability and resiliency of the distribution system.
基金the Incubation Project of State Grid Jiangsu Corporation of China“Construction and Application of Intelligent Load Transferring Platform for Active Distribution Networks”(JF2023031).
文摘When a line failure occurs in a power grid, a load transfer is implemented to reconfigure the network by changingthe states of tie-switches and load demands. Computation speed is one of the major performance indicators inpower grid load transfer, as a fast load transfer model can greatly reduce the economic loss of post-fault powergrids. In this study, a reinforcement learning method is developed based on a deep deterministic policy gradient.The tedious training process of the reinforcement learning model can be conducted offline, so the model showssatisfactory performance in real-time operation, indicating that it is suitable for fast load transfer. Consideringthat the reinforcement learning model performs poorly in satisfying safety constraints, a safe action-correctionframework is proposed to modify the learning model. In the framework, the action of load shedding is correctedaccording to sensitivity analysis results under a small discrete increment so as to match the constraints of line flowlimits. The results of case studies indicate that the proposed method is practical for fast and safe power grid loadtransfer.
基金This project has received funding from the Fuel Cells and Hydrogen 2 Joint Undertaking under grant agreement No.735485This joint undertaking receives support from the European Union’s Horizon 2020 research and innovation programme and Hydrogen Europe and N.ERGHY.
文摘Electrolysers,which convert electricity into hydrogen,have the potential to offer a variety of electrical-grid services,therefore facilitating the integration of intermittent renewables into electrical grids.Among various activities that aim to unlock this hidden value,the 3-year European Union project QualyGridS launched in 2017 aims to establish standardized testing protocols for electrolysers to perform electricity-grid services.This paper shares experience and intermediate results of QualyGridS with respect to the testing protocols,test benches and testing results.The results of this work facilitate mutual understanding between the electricity industry and the hydrogen industry,support further development of the cross-sector testing standards,guide the design and selection of grid-service-oriented electrolyser applications and foster the transition towards a fossil-free-energy future based on high shares of hydrogen and other renewable solutions.
文摘Due to the increasing share of renewable energy, new requirements are placed on control room software. Such software is often exclusive to the supplier, but other suppliers could offer new and better methods. For security reasons, external applications often have no direct data access to control room software. Such software can provide information about the power grid via a periodic file transfer in CIM (Common Information Model) format. These files are often very large, containing complete records, delivering information not always relevant to the external applications. Extracting the relevant information required by external applications can be time-consuming, thus presenting a problem for time-critical applications. This paper presents a method allowing different applications to efficiently access the relevant data from the massive data stream contained in the CIM files. This method has been tested with a distribution system operator and clearly increases performance, allowing different applications to access the relevant data.
