To reduce carbon emissions,clean energy is being integrated into the power system.Wind power is connected to the grid in a distributed form,but its high variability poses a challenge to grid stability.This article com...To reduce carbon emissions,clean energy is being integrated into the power system.Wind power is connected to the grid in a distributed form,but its high variability poses a challenge to grid stability.This article combines wind turbine monitoring data with numerical weather prediction(NWP)data to create a suitable wind power prediction framework for distributed grids.First,high-precision NWP of the turbine range is achieved using weather research and forecasting models(WRF),and Kriging interpolation locates predicted meteorological data at the turbine site.Then,a preliminary predicted power series is obtained based on the fan’s wind speed-power conversion curve,and historical power is reconstructed using variational mode decomposition(VMD)filtering to form input variables in chronological order.Finally,input variables of a single turbine enter the temporal convolutional network(TCN)to complete initial feature extraction,and then integrate the outputs of all TCN layers using Long Short Term Memory Networks(LSTM)to obtain power prediction sequences for all turbine positions.The proposed method was tested on a wind farm connected to a distributed power grid,and the results showed it to be superior to existing typical methods.展开更多
After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and de...After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and demand in the distribution network,exacerbating the phenomenon of wind and solar power wastage.As a novel power system model,the fundamental concept of Regional Autonomous Power Grids(RAPGs)is to achieve localized management and energy autonomy,thereby facilitating the effective consumption of DGs.Therefore,this paper proposes a distributed resource planning strategy that enhances the autonomy capabilities of regional power grids by considering multiple evaluation indexes for autonomy.First,a regional Energy Storage(ES)configuration strategy is proposed.This strategy can select a suitable reference value for the upper limit of ES configuration based on the regional load andDGoutput to maximize the elimination of source load deviations in the region as the upper limit constraint of ES capacity.Then,a control strategy for regional ES is proposed,the charging and discharging reference line of ES is set,and multiple autonomy and economic indexes are used as objective functions to select different proportions of ES to control the distributed resources of the regional power grid and establish evaluation indexes of the internal regional generation and load power ratio,the proportion of power supply matching hours,new energy consumption rate and tie line power imbalance outside the region to evaluate changes in the regional autonomy capabilities.The final simulation results showthat in the real regional grid example,the planning method in the planning year in the region of the overall power supply matching hour ratio and new energy consumption rate increased by 3.9%and 4.8%on average,and the power imbalance of the tie line decreased by 7.8%on average.The proposed planning approach enables the maximization of regional autonomy while effectively smoothing the fluctuation of power exchange between the regional grid and the higher-level grid.This presents a rational and effective planning solution for the regional grid,facilitating the coordinated development between the region and the distribution network.展开更多
The installed capacity of a large scale wind power plant will be up to a number of hundreds MW, and the wind power is transmitted to load centers through long distance transmission lines with 220 kV, 500 kV, or 750 kV...The installed capacity of a large scale wind power plant will be up to a number of hundreds MW, and the wind power is transmitted to load centers through long distance transmission lines with 220 kV, 500 kV, or 750 kV. Therefore, it is necessary not only considering the power transmission line between a wind power plant and the first connection node of the power network, but also the power network among the group of those wind power plants in a wind power base, the integration network from the base to the existed grids, as well as the distribution and consumption of the wind power generation by loads. Meanwhile, the impact of wind power stochastic fluctuation on power systems must be studied. In recent years, wind power prediction technology has been studied by the utilities and wind power plants. As a matter of fact, some European countries have used this prediction technology as a tool in national power dispatch centers and wind power companies.展开更多
In this paper the growing process of China power grid from formation of local power grids to nationwide interconnection is reviewed. The scale and structure of power grid construction in the near future, especially th...In this paper the growing process of China power grid from formation of local power grids to nationwide interconnection is reviewed. The scale and structure of power grid construction in the near future, especially the planning on sending power from west to east, North-South supplementation and nationwide interconnection are introduced. In addition, the technologies to be extended in future grid development are briefed, such as HVDC, FACTS and compact transmission line, etc.展开更多
China Electricity Council organized competent authorities across the industry of electric power to work out the ＂Research Reports on the 12^th Five-Year Plan for Electric＂ Power lndustry ＂＂ in nearly one year, whi...China Electricity Council organized competent authorities across the industry of electric power to work out the ＂Research Reports on the 12^th Five-Year Plan for Electric＂ Power lndustry ＂＂ in nearly one year, which provides a reference/or governmental departments to formulate the 12^th Five-Year Plan on energy and electric power industry. The magazine should publish the serial reports inchliding power sources, power grids, equipment manufacture, energy and environment, and power economics. This paper presents the part of ＂ power grids, ＂ in which the strategies of developing power grids are put forward.展开更多
At the end of last year, the editors from Power and Electrical Engineers interviewed Zhou Xiaoxin on "Fundamental Research on Enhancing Operation Reliability for Large-Scale Interconnected Power Grids", a pr...At the end of last year, the editors from Power and Electrical Engineers interviewed Zhou Xiaoxin on "Fundamental Research on Enhancing Operation Reliability for Large-Scale Interconnected Power Grids", a project of "973 Program". Mr. Zhou, the chief engineer of China Electric Power Research Institute(CEPRI) and an academician of Chinese Academy of Sciences, is the chief scientist in charge of this research project.展开更多
Since October 2008,China's social consumption of electricity had,for the first time,grown negatively compared to the same period of the previous year,and in November the negative growth range further expanded. The...Since October 2008,China's social consumption of electricity had,for the first time,grown negatively compared to the same period of the previous year,and in November the negative growth range further expanded. The major pressure faced by the electricity industry has now turned from the contradiction between coal and electricity to electricity quantity. This is undoubtedly a true and new test to electricity enterprises which get used to high growth but are now suffering great losses. The reform of electricity system has already been in great difficulties and now is getting into a more serious situation. In order to help readers improve their knowledge and understanding of the current tough situation faced by the electricity industry and discuss how to alleviate and get through the difficulty resulted from the economic crisis "encountered once every one hundred years" by joint efforts of all parties concerned,a Seminar on Crisis and Countermeasures for Electricity Industry was held on November 20,2008. Here are some extracts from the speeches of four experts.展开更多
This paper proposes a new power grid investment prediction model based on the deep restricted Boltzmann machine(DRBM)optimized by the Lion algorithm(LA).Firstly,two factors including transmission and distribution pric...This paper proposes a new power grid investment prediction model based on the deep restricted Boltzmann machine(DRBM)optimized by the Lion algorithm(LA).Firstly,two factors including transmission and distribution price reform(TDPR)and 5G station construction were comprehensively incorporated into the consideration of influencing factors,and the fuzzy threshold method was used to screen out critical influencing factors.Then,the LA was used to optimize the parameters of the DRBM model to improve the model’s prediction accuracy,and the model was trained with the selected influencing factors and investment.Finally,the LA-DRBM model was used to predict the investment of a power grid enterprise,and the final prediction result was obtained by modifying the initial result with the modifying factors.The LA-DRBMmodel compensates for the deficiency of the singlemodel,and greatly improves the investment prediction accuracy of the power grid.In this study,a power grid enterprise was taken as an example to carry out an empirical analysis to prove the validity of the model,and a comparison with the RBM,support vector machine(SVM),back propagation neural network(BPNN),and regression model was conducted to verify the superiority of the model.The conclusion indicates that the proposed model has a strong generalization ability and good robustness,is able to abstract the combination of low-level features into high-level features,and can improve the efficiency of the model’s calculations for investment prediction of power grid enterprises.展开更多
The future of electricity systems will compose of small-scale generation and distribution where end-users will be active participants with localized energy management systems that are able to interact on a free energy...The future of electricity systems will compose of small-scale generation and distribution where end-users will be active participants with localized energy management systems that are able to interact on a free energy market. Software agents will most likely control power assets and interact together to decide the best and safest configuration of the power grid system. This paper presents a design of agents that can be deployed in real-time with capabilities that include optimization of resources, intensive computation, and appropriate decision-making. Jordan 51-bus system has been used for simulation with a total generation capacity of 4050 MW of which 230 MW represent</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> renewable energy. The economic analyses demonstrated the use of smart grid technologies with 2016 generation</span><span style="font-family:""><span style="font-family:Verdana;">—</span><span style="font-family:Verdana;">load profiles for nominal liquified gas (NLG) prices and </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;">20% sensitivity analysis. The results have shown variations in the range of 1% in the price of MWh with smart grid technologies. These variations are mainly driven by the fact that agents shift power generation to renewable power plants to produce maximum power at peak hours. As a result, there is a positive economic impact in both NLG </span><span style="font-family:Verdana;">±</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">20% sensitivity analysis, due to the fact that agents coordinate to better displace expensive thermal generation with renewable generation. It is evident that renewable resources compensate for power at peak times and provide economic benefits and savings.展开更多
Based on an analysis of the misunderstandings and problems concerning wind power development, this paper summarizes the experiences of the coordinated development of wind power and power grids in foreign countries, an...Based on an analysis of the misunderstandings and problems concerning wind power development, this paper summarizes the experiences of the coordinated development of wind power and power grids in foreign countries, and proposes principles and strategies for the coordinated development of wind power and power grids, and related measures and suggestions for large scale development of wind power in China.展开更多
The safety and stability study on Northeast, North, East, Northwest and Central China power grids had been carried out, which provided technical supports to planning design of regional power grids. By analyzing safety...The safety and stability study on Northeast, North, East, Northwest and Central China power grids had been carried out, which provided technical supports to planning design of regional power grids. By analyzing safety and stability under severe faults in regional power grids, revealed weaknesses on power grid configurations and measures for preventing from loss of stability were presented. In comparison of various schemes of power system safety and stability among parts of power grids, more than two recommended schemes can be chosen as reference in planning design for regional power grids. Considering the safety and stability control measures necessary for each power grids, it is believed the trunk networks of all power grids can fulfill the third criteria of Guideline for Power System Safety and Stability, while the weakness and predominated hydropower may deteriorate safety and stability of power grids. The power grid shall be regulated in line with the variation of boundary conditions.展开更多
This paper analyzes the possibility and benefits of interconnection of Northwest Power Grid with North China and Shangdong power grids. With different energy resources and power demand patterns, these three power grid...This paper analyzes the possibility and benefits of interconnection of Northwest Power Grid with North China and Shangdong power grids. With different energy resources and power demand patterns, these three power grids have large potential benefits in future interconnection.展开更多
Power grids play a critical role in modern society, serving as the lifeline of a well-functioning economy. This article presents a first large-scale study on the risk estimation of tropical cyclone(TC)-induced winds a...Power grids play a critical role in modern society, serving as the lifeline of a well-functioning economy. This article presents a first large-scale study on the risk estimation of tropical cyclone(TC)-induced winds and coastal floods, which can widely impact power grids in Southeast and East Asia. Our comprehensive risk model incorporates detailed infrastructure data from OpenStreetMap(OSM) and government power grid maps, along with global hazard maps and vulnerability curves. The results reveal that the estimated expected annual damages from TCs and coastal floods to OSM-mapped assets account for approximately 0.07%(0.00–0.38%) and 0.02%(0.00–0.02%) of the total GDP of the study area, respectively. We analyzed the main sources of uncertainty in the risk model and emphasized the importance of understanding asset vulnerability.These results highlight the urgent need to strengthen power infrastructure to withstand the impacts of natural hazards, and the significance of reliable risk information for improving power grid design and planning. Focusing on developing more region-specific infrastructure data and vulnerability curves will improve the accuracy of risk estimation and provide valuable insights not only for the electricity sector but also for customers of other infrastructure systems that heavily rely on a stable supply of electricity.展开更多
Power grids,due to their lack of network redundancy and structural interdependence,are particularly vulnerable to cascading failures,a phenomenon where a few failed nodes—having their loads exceeding their capacities...Power grids,due to their lack of network redundancy and structural interdependence,are particularly vulnerable to cascading failures,a phenomenon where a few failed nodes—having their loads exceeding their capacities—can trigger a widespread collapse of all nodes.Here,we extend the cascading failure(Motter-Lai)model to a more realistic perspective,where each node’s load capacity is determined to be nonlinearly correlated with the node’s centrality.Our analysis encompasses a range of synthetic networks featuring small-world or scale-free properties,as well as real-world network configurations like the IEEE bus systems and the US power grid.We find that fine-tuning this nonlinear relationship can significantly enhance a network’s robustness against cascading failures when the network nodes are under attack.Additionally,the selection of initial nodes and the attack strategies also impact overall network robustness.Our findings offer valuable insights for improving the safety and resilience of power grids,bringing us closer to understanding cascading failures in a more realistic context.展开更多
Power grids play a crucial role in connecting electricity suppliers and consumers.They facilitate efficient power transmission and energy management,significantly contributing to the transition toward low-carbon pract...Power grids play a crucial role in connecting electricity suppliers and consumers.They facilitate efficient power transmission and energy management,significantly contributing to the transition toward low-carbon practices across both upstream and downstream sectors.Effectively managing carbon reduction in the power industry is essential for enhancing carbon reduction efficiency and achieving dual-carbon goals.Recent studies have focused on the outcomes of carbon reduction efforts rather than the management process.However,when power grids prioritize the process of carbon reduction in their management,they are more likely to achieve better results.To address this gap,we propose an evaluation model for managing carbon reduction activities in power grids,comprising the carbon management efficiency(CME)module based on the maturity model and the carbon reduction efficiency(CRE)module based on the entropy method.The CME module provides a scorecard corresponding to a detailed and continuous evaluation model for carbon management processes to calculate its performance.Simultaneously,the CRE module relates carbon reduction results to the development direction of the government and power grid,allowing for effective adjustments and updates based on actual situations.The evaluation model was applied to provincial power grids within the China Central Power Grid.The results reveal that despite some fluctuations in carbon reduction performance,provincial power grids within the China Central Power Grid have made continuous progress in carbon reduction efforts.According to the synergy model,there is evidence suggesting that power grids are steadily improving their carbon reduction performance,and a more organized approach would lead to a greater degree of synergy.The evaluation model applies to power grids,and its framework can be extended to other industries,providing a theoretical reference for evaluating their carbon reduction efforts.展开更多
The urban power grid(UPG)combines transmission and distribution networks.Past studies on UPG congestion mitigation have primarily focused on relieving local congestion while ignoring large-scale energy transfer with s...The urban power grid(UPG)combines transmission and distribution networks.Past studies on UPG congestion mitigation have primarily focused on relieving local congestion while ignoring large-scale energy transfer with safety margins and load balancing.This situation is expected to worsen with the proliferation of renewable energy and electric vehicles.In this paper,a two-layer congestion mitigation framework is proposed,one which considers the congestion of the UPG with flexible topologies.In the upper-layer,the particle swarm optimization algorithm is employed to optimize the power supply distribution(PSD)of substation transformers.This is known as the upper-layer PSD.The lower-layer model recalculates the new PSD,known as the lower-layer PSD,based on the topology candidates.A candidate topology is at an optimum when the Euclidean distance mismatch between the upper-and lower-layer PSDs is the smallest.This optimum topology is tested by standard power flow to ascertain its feasibility.The optimum transitioning sequence between the initial and optimum topologies is also determined by the two-layer framework to minimize voltage deviation and line overloading of the UPG considering dynamic thermal rating.The proposed framework is tested on a 56-node test system.Results show that the proposed framework can significantly reduce congestion,maintain safety margins,and determine the optimum transitioning sequence.展开更多
With the rapid development of urban power grids and the large-scale integration of renewable energy, traditional power grid fault diagnosis techniques struggle to address the complexities of diagnosing faults in intri...With the rapid development of urban power grids and the large-scale integration of renewable energy, traditional power grid fault diagnosis techniques struggle to address the complexities of diagnosing faults in intricate power grid systems. Although artificial intelligence technologies offer new solutions for power grid fault diagnosis, the difficulty in acquiring labeled grid data limits the development of AI technologies in this area. In response to these challenges, this study proposes a semi-supervised learning framework with self-supervised and adaptive threshold (SAT-SSL) for fault detection and classification in power grids. Compared to other methods, our method reduces the dependence on labeling data while maintaining high recognition accuracy. First, we utilize frequency domain analysis on power grid data to filter abnormal events, then classify and label these events based on visual features, to creating a power grid dataset. Subsequently, we employ the Yule–Walker algorithm extract features from the power grid data. Then we construct a semi-supervised learning framework, incorporating self-supervised loss and dynamic threshold to enhance information extraction capabilities and adaptability across different scenarios of the model. Finally, the power grid dataset along with two benchmark datasets are used to validate the model’s functionality. The results indicate that our model achieves a low error rate across various scenarios and different amounts of labels. In power grid dataset, When retaining just 5% of the labels, the error rate is only 6.15%, which proves that this method can achieve accurate grid fault detection and classification with a limited amount of labeled data.展开更多
Due to the effects of windless and sunless weather,new power systems dominated by renewable energy sources ex-perience power supply shortages,which lead to severe electrici-ty shortages.Because of the insufficient pro...Due to the effects of windless and sunless weather,new power systems dominated by renewable energy sources ex-perience power supply shortages,which lead to severe electrici-ty shortages.Because of the insufficient proportion of controlla-ble thermal power in these systems,this problem must be ad-dressed from the load side.This study proposes an orderly pow-er utilization(OPU)method with load as the primary dispatch-ing object to address the problem of severe electricity shortag-es.The principles and architecture of the new urban power grid(NUPG)OPU are proposed to complete the load curtail-ment task and minimize the effects on social production and daily life.A flexible load baseline division method is proposed that considers the effects of factors such as gross domestic prod-uct,pollutant emission,and carbon emission to increase the flex-ibility and applicability of the proposed method.In addition,an NUPG OPU model based on the load baseline is proposed,in which the electric quantity balance aggregator(EQBA)serves as a regular participant in the OPU and eliminates the need for other user involvement within its capacity range.The electric quantity reserve aggregator(EQRA)functions as a supplemen-tary participant in the OPU and primarily performs the remain-ing tasks of the EQBA.The electric power balance aggregator primarily offsets the power fluctuations of the OPU.Case stud-ies demonstrate the effectiveness and superiority of the pro-posed model in ensuring the completion of the load curtailment task,enhancing the flexibility and fairness of OPUs,and im-proving the applicability of the proposed method.Index Terms-Electric power balance,electric quantity bal-ance,electricity shortage,orderly power utilization,new urban powergrid.展开更多
In terms of model-free voltage control methods,when the device or topology of the system changes,the model’s accuracy often decreases,so an adaptive model is needed to coordinate the changes of input.To overcome the ...In terms of model-free voltage control methods,when the device or topology of the system changes,the model’s accuracy often decreases,so an adaptive model is needed to coordinate the changes of input.To overcome the defects of a model-free control method,this paper proposes an automatic voltage control(AVC)method for differential power grids based on transfer learning and deep reinforcement learning.First,when constructing the Markov game of AVC,both the magnitude and number of voltage deviations are taken into account in the reward.Then,an AVC method based on constrained multiagent deep reinforcement learning(DRL)is developed.To further improve learning efficiency,domain knowledge is used to reduce action space.Next,distribution adaptation transfer learning is introduced for the AVC transfer circumstance of systems with the same structure but distinct topological relations/parameters,which can perform well without any further training even if the structure changes.Moreover,for the AVC transfer circumstance of various power grids,parameter-based transfer learning is created,which enhances the target system’s training speed and effect.Finally,the method’s efficacy is tested using two IEEE systems and two real-world power grids.展开更多
基金funded by National Key Research and Development Program of China (2021YFB2601400)。
文摘To reduce carbon emissions,clean energy is being integrated into the power system.Wind power is connected to the grid in a distributed form,but its high variability poses a challenge to grid stability.This article combines wind turbine monitoring data with numerical weather prediction(NWP)data to create a suitable wind power prediction framework for distributed grids.First,high-precision NWP of the turbine range is achieved using weather research and forecasting models(WRF),and Kriging interpolation locates predicted meteorological data at the turbine site.Then,a preliminary predicted power series is obtained based on the fan’s wind speed-power conversion curve,and historical power is reconstructed using variational mode decomposition(VMD)filtering to form input variables in chronological order.Finally,input variables of a single turbine enter the temporal convolutional network(TCN)to complete initial feature extraction,and then integrate the outputs of all TCN layers using Long Short Term Memory Networks(LSTM)to obtain power prediction sequences for all turbine positions.The proposed method was tested on a wind farm connected to a distributed power grid,and the results showed it to be superior to existing typical methods.
基金supported by the State Grid Henan Economic Research Institute Science and Technology Project“Calculation and Demonstration of Distributed Photovoltaic Open Capacity Based on Multi-Source Heterogeneous Data”(5217L0230013).
文摘After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and demand in the distribution network,exacerbating the phenomenon of wind and solar power wastage.As a novel power system model,the fundamental concept of Regional Autonomous Power Grids(RAPGs)is to achieve localized management and energy autonomy,thereby facilitating the effective consumption of DGs.Therefore,this paper proposes a distributed resource planning strategy that enhances the autonomy capabilities of regional power grids by considering multiple evaluation indexes for autonomy.First,a regional Energy Storage(ES)configuration strategy is proposed.This strategy can select a suitable reference value for the upper limit of ES configuration based on the regional load andDGoutput to maximize the elimination of source load deviations in the region as the upper limit constraint of ES capacity.Then,a control strategy for regional ES is proposed,the charging and discharging reference line of ES is set,and multiple autonomy and economic indexes are used as objective functions to select different proportions of ES to control the distributed resources of the regional power grid and establish evaluation indexes of the internal regional generation and load power ratio,the proportion of power supply matching hours,new energy consumption rate and tie line power imbalance outside the region to evaluate changes in the regional autonomy capabilities.The final simulation results showthat in the real regional grid example,the planning method in the planning year in the region of the overall power supply matching hour ratio and new energy consumption rate increased by 3.9%and 4.8%on average,and the power imbalance of the tie line decreased by 7.8%on average.The proposed planning approach enables the maximization of regional autonomy while effectively smoothing the fluctuation of power exchange between the regional grid and the higher-level grid.This presents a rational and effective planning solution for the regional grid,facilitating the coordinated development between the region and the distribution network.
文摘The installed capacity of a large scale wind power plant will be up to a number of hundreds MW, and the wind power is transmitted to load centers through long distance transmission lines with 220 kV, 500 kV, or 750 kV. Therefore, it is necessary not only considering the power transmission line between a wind power plant and the first connection node of the power network, but also the power network among the group of those wind power plants in a wind power base, the integration network from the base to the existed grids, as well as the distribution and consumption of the wind power generation by loads. Meanwhile, the impact of wind power stochastic fluctuation on power systems must be studied. In recent years, wind power prediction technology has been studied by the utilities and wind power plants. As a matter of fact, some European countries have used this prediction technology as a tool in national power dispatch centers and wind power companies.
文摘In this paper the growing process of China power grid from formation of local power grids to nationwide interconnection is reviewed. The scale and structure of power grid construction in the near future, especially the planning on sending power from west to east, North-South supplementation and nationwide interconnection are introduced. In addition, the technologies to be extended in future grid development are briefed, such as HVDC, FACTS and compact transmission line, etc.
文摘China Electricity Council organized competent authorities across the industry of electric power to work out the ＂Research Reports on the 12^th Five-Year Plan for Electric＂ Power lndustry ＂＂ in nearly one year, which provides a reference/or governmental departments to formulate the 12^th Five-Year Plan on energy and electric power industry. The magazine should publish the serial reports inchliding power sources, power grids, equipment manufacture, energy and environment, and power economics. This paper presents the part of ＂ power grids, ＂ in which the strategies of developing power grids are put forward.
文摘At the end of last year, the editors from Power and Electrical Engineers interviewed Zhou Xiaoxin on "Fundamental Research on Enhancing Operation Reliability for Large-Scale Interconnected Power Grids", a project of "973 Program". Mr. Zhou, the chief engineer of China Electric Power Research Institute(CEPRI) and an academician of Chinese Academy of Sciences, is the chief scientist in charge of this research project.
文摘Since October 2008,China's social consumption of electricity had,for the first time,grown negatively compared to the same period of the previous year,and in November the negative growth range further expanded. The major pressure faced by the electricity industry has now turned from the contradiction between coal and electricity to electricity quantity. This is undoubtedly a true and new test to electricity enterprises which get used to high growth but are now suffering great losses. The reform of electricity system has already been in great difficulties and now is getting into a more serious situation. In order to help readers improve their knowledge and understanding of the current tough situation faced by the electricity industry and discuss how to alleviate and get through the difficulty resulted from the economic crisis "encountered once every one hundred years" by joint efforts of all parties concerned,a Seminar on Crisis and Countermeasures for Electricity Industry was held on November 20,2008. Here are some extracts from the speeches of four experts.
基金the National Key Research and Development Program of China(Grant No.2020YFB1707804)the 2018 Key Projects of Philosophy and Social Sciences Research(Grant No.18JZD032)Natural Science Foundation of Hebei Province(Grant No.G2020403008).
文摘This paper proposes a new power grid investment prediction model based on the deep restricted Boltzmann machine(DRBM)optimized by the Lion algorithm(LA).Firstly,two factors including transmission and distribution price reform(TDPR)and 5G station construction were comprehensively incorporated into the consideration of influencing factors,and the fuzzy threshold method was used to screen out critical influencing factors.Then,the LA was used to optimize the parameters of the DRBM model to improve the model’s prediction accuracy,and the model was trained with the selected influencing factors and investment.Finally,the LA-DRBM model was used to predict the investment of a power grid enterprise,and the final prediction result was obtained by modifying the initial result with the modifying factors.The LA-DRBMmodel compensates for the deficiency of the singlemodel,and greatly improves the investment prediction accuracy of the power grid.In this study,a power grid enterprise was taken as an example to carry out an empirical analysis to prove the validity of the model,and a comparison with the RBM,support vector machine(SVM),back propagation neural network(BPNN),and regression model was conducted to verify the superiority of the model.The conclusion indicates that the proposed model has a strong generalization ability and good robustness,is able to abstract the combination of low-level features into high-level features,and can improve the efficiency of the model’s calculations for investment prediction of power grid enterprises.
文摘The future of electricity systems will compose of small-scale generation and distribution where end-users will be active participants with localized energy management systems that are able to interact on a free energy market. Software agents will most likely control power assets and interact together to decide the best and safest configuration of the power grid system. This paper presents a design of agents that can be deployed in real-time with capabilities that include optimization of resources, intensive computation, and appropriate decision-making. Jordan 51-bus system has been used for simulation with a total generation capacity of 4050 MW of which 230 MW represent</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> renewable energy. The economic analyses demonstrated the use of smart grid technologies with 2016 generation</span><span style="font-family:""><span style="font-family:Verdana;">—</span><span style="font-family:Verdana;">load profiles for nominal liquified gas (NLG) prices and </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;">20% sensitivity analysis. The results have shown variations in the range of 1% in the price of MWh with smart grid technologies. These variations are mainly driven by the fact that agents shift power generation to renewable power plants to produce maximum power at peak hours. As a result, there is a positive economic impact in both NLG </span><span style="font-family:Verdana;">±</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">20% sensitivity analysis, due to the fact that agents coordinate to better displace expensive thermal generation with renewable generation. It is evident that renewable resources compensate for power at peak times and provide economic benefits and savings.
文摘Based on an analysis of the misunderstandings and problems concerning wind power development, this paper summarizes the experiences of the coordinated development of wind power and power grids in foreign countries, and proposes principles and strategies for the coordinated development of wind power and power grids, and related measures and suggestions for large scale development of wind power in China.
文摘The safety and stability study on Northeast, North, East, Northwest and Central China power grids had been carried out, which provided technical supports to planning design of regional power grids. By analyzing safety and stability under severe faults in regional power grids, revealed weaknesses on power grid configurations and measures for preventing from loss of stability were presented. In comparison of various schemes of power system safety and stability among parts of power grids, more than two recommended schemes can be chosen as reference in planning design for regional power grids. Considering the safety and stability control measures necessary for each power grids, it is believed the trunk networks of all power grids can fulfill the third criteria of Guideline for Power System Safety and Stability, while the weakness and predominated hydropower may deteriorate safety and stability of power grids. The power grid shall be regulated in line with the variation of boundary conditions.
文摘This paper analyzes the possibility and benefits of interconnection of Northwest Power Grid with North China and Shangdong power grids. With different energy resources and power demand patterns, these three power grids have large potential benefits in future interconnection.
基金supported by the China Scholarship Council.Elco E.Koks,Philip J.Ward,and Sadhana Nirandjan were funded by the European Union’s Horizon Europe MIRACA project(Grant Agreement No.101093854)Horizon 2020 projects MYRIAD-EU(Grant Agreement No.101003276)CoCliCo(Grant Agreement No.101003598).
文摘Power grids play a critical role in modern society, serving as the lifeline of a well-functioning economy. This article presents a first large-scale study on the risk estimation of tropical cyclone(TC)-induced winds and coastal floods, which can widely impact power grids in Southeast and East Asia. Our comprehensive risk model incorporates detailed infrastructure data from OpenStreetMap(OSM) and government power grid maps, along with global hazard maps and vulnerability curves. The results reveal that the estimated expected annual damages from TCs and coastal floods to OSM-mapped assets account for approximately 0.07%(0.00–0.38%) and 0.02%(0.00–0.02%) of the total GDP of the study area, respectively. We analyzed the main sources of uncertainty in the risk model and emphasized the importance of understanding asset vulnerability.These results highlight the urgent need to strengthen power infrastructure to withstand the impacts of natural hazards, and the significance of reliable risk information for improving power grid design and planning. Focusing on developing more region-specific infrastructure data and vulnerability curves will improve the accuracy of risk estimation and provide valuable insights not only for the electricity sector but also for customers of other infrastructure systems that heavily rely on a stable supply of electricity.
基金supported by the National Key R&D Program of China for International S&T Cooperation Projects(No.2019YFE0118700)National Natural Science Foundation of China(Nos.62222306 and 61973110)+1 种基金Hunan Young Talents Science and Technology Innovation Project(No.2020RC3048)Natural Science Found for Distinguished Young Scholars of Hunan Province(No.2021JJ10030).
文摘Power grids,due to their lack of network redundancy and structural interdependence,are particularly vulnerable to cascading failures,a phenomenon where a few failed nodes—having their loads exceeding their capacities—can trigger a widespread collapse of all nodes.Here,we extend the cascading failure(Motter-Lai)model to a more realistic perspective,where each node’s load capacity is determined to be nonlinearly correlated with the node’s centrality.Our analysis encompasses a range of synthetic networks featuring small-world or scale-free properties,as well as real-world network configurations like the IEEE bus systems and the US power grid.We find that fine-tuning this nonlinear relationship can significantly enhance a network’s robustness against cascading failures when the network nodes are under attack.Additionally,the selection of initial nodes and the attack strategies also impact overall network robustness.Our findings offer valuable insights for improving the safety and resilience of power grids,bringing us closer to understanding cascading failures in a more realistic context.
基金supported by the Science and Technology Program of China Southern Power Grid Co.,Ltd.(Grant No.YNKJXM20222173)the Reserve Talents Program for Middle-aged and Young Leaders of Disciplines in Science and Technology of Yunnan Province,China(Grant No.202105AC160014).
文摘Power grids play a crucial role in connecting electricity suppliers and consumers.They facilitate efficient power transmission and energy management,significantly contributing to the transition toward low-carbon practices across both upstream and downstream sectors.Effectively managing carbon reduction in the power industry is essential for enhancing carbon reduction efficiency and achieving dual-carbon goals.Recent studies have focused on the outcomes of carbon reduction efforts rather than the management process.However,when power grids prioritize the process of carbon reduction in their management,they are more likely to achieve better results.To address this gap,we propose an evaluation model for managing carbon reduction activities in power grids,comprising the carbon management efficiency(CME)module based on the maturity model and the carbon reduction efficiency(CRE)module based on the entropy method.The CME module provides a scorecard corresponding to a detailed and continuous evaluation model for carbon management processes to calculate its performance.Simultaneously,the CRE module relates carbon reduction results to the development direction of the government and power grid,allowing for effective adjustments and updates based on actual situations.The evaluation model was applied to provincial power grids within the China Central Power Grid.The results reveal that despite some fluctuations in carbon reduction performance,provincial power grids within the China Central Power Grid have made continuous progress in carbon reduction efforts.According to the synergy model,there is evidence suggesting that power grids are steadily improving their carbon reduction performance,and a more organized approach would lead to a greater degree of synergy.The evaluation model applies to power grids,and its framework can be extended to other industries,providing a theoretical reference for evaluating their carbon reduction efforts.
基金supported by the Universiti Sains Malaysia,Research University Team(RUTeam)Grant Scheme(No.1001/PELECT/8580011).
文摘The urban power grid(UPG)combines transmission and distribution networks.Past studies on UPG congestion mitigation have primarily focused on relieving local congestion while ignoring large-scale energy transfer with safety margins and load balancing.This situation is expected to worsen with the proliferation of renewable energy and electric vehicles.In this paper,a two-layer congestion mitigation framework is proposed,one which considers the congestion of the UPG with flexible topologies.In the upper-layer,the particle swarm optimization algorithm is employed to optimize the power supply distribution(PSD)of substation transformers.This is known as the upper-layer PSD.The lower-layer model recalculates the new PSD,known as the lower-layer PSD,based on the topology candidates.A candidate topology is at an optimum when the Euclidean distance mismatch between the upper-and lower-layer PSDs is the smallest.This optimum topology is tested by standard power flow to ascertain its feasibility.The optimum transitioning sequence between the initial and optimum topologies is also determined by the two-layer framework to minimize voltage deviation and line overloading of the UPG considering dynamic thermal rating.The proposed framework is tested on a 56-node test system.Results show that the proposed framework can significantly reduce congestion,maintain safety margins,and determine the optimum transitioning sequence.
基金supported by the National Natural Science Foundation China under Grants number 62073232,and the Science and Technology Project of Shenzhen,China(KCXST20221021111402006,JSGG20220831105800002)and the“Nanling Team Project”of Shaoguan city,and the Science and Technology project of Tianjin,China(22YFYSHZ00330)+1 种基金and Shenzhen Excellent Innovative Talents RCYX20221008093036022,Shenzhen-HongKong joint funding project(A)(SGDX20230116092053005)the Shenzhen Undertaking the National Major Science and Technology Program,China(CJGJZD20220517141405012).
文摘With the rapid development of urban power grids and the large-scale integration of renewable energy, traditional power grid fault diagnosis techniques struggle to address the complexities of diagnosing faults in intricate power grid systems. Although artificial intelligence technologies offer new solutions for power grid fault diagnosis, the difficulty in acquiring labeled grid data limits the development of AI technologies in this area. In response to these challenges, this study proposes a semi-supervised learning framework with self-supervised and adaptive threshold (SAT-SSL) for fault detection and classification in power grids. Compared to other methods, our method reduces the dependence on labeling data while maintaining high recognition accuracy. First, we utilize frequency domain analysis on power grid data to filter abnormal events, then classify and label these events based on visual features, to creating a power grid dataset. Subsequently, we employ the Yule–Walker algorithm extract features from the power grid data. Then we construct a semi-supervised learning framework, incorporating self-supervised loss and dynamic threshold to enhance information extraction capabilities and adaptability across different scenarios of the model. Finally, the power grid dataset along with two benchmark datasets are used to validate the model’s functionality. The results indicate that our model achieves a low error rate across various scenarios and different amounts of labels. In power grid dataset, When retaining just 5% of the labels, the error rate is only 6.15%, which proves that this method can achieve accurate grid fault detection and classification with a limited amount of labeled data.
基金This work was supported by the National Natural Science Foundation of China(No.51877049).
文摘Due to the effects of windless and sunless weather,new power systems dominated by renewable energy sources ex-perience power supply shortages,which lead to severe electrici-ty shortages.Because of the insufficient proportion of controlla-ble thermal power in these systems,this problem must be ad-dressed from the load side.This study proposes an orderly pow-er utilization(OPU)method with load as the primary dispatch-ing object to address the problem of severe electricity shortag-es.The principles and architecture of the new urban power grid(NUPG)OPU are proposed to complete the load curtail-ment task and minimize the effects on social production and daily life.A flexible load baseline division method is proposed that considers the effects of factors such as gross domestic prod-uct,pollutant emission,and carbon emission to increase the flex-ibility and applicability of the proposed method.In addition,an NUPG OPU model based on the load baseline is proposed,in which the electric quantity balance aggregator(EQBA)serves as a regular participant in the OPU and eliminates the need for other user involvement within its capacity range.The electric quantity reserve aggregator(EQRA)functions as a supplemen-tary participant in the OPU and primarily performs the remain-ing tasks of the EQBA.The electric power balance aggregator primarily offsets the power fluctuations of the OPU.Case stud-ies demonstrate the effectiveness and superiority of the pro-posed model in ensuring the completion of the load curtailment task,enhancing the flexibility and fairness of OPUs,and im-proving the applicability of the proposed method.Index Terms-Electric power balance,electric quantity bal-ance,electricity shortage,orderly power utilization,new urban powergrid.
基金supported by the National Science Foundation of China(U1866602).
文摘In terms of model-free voltage control methods,when the device or topology of the system changes,the model’s accuracy often decreases,so an adaptive model is needed to coordinate the changes of input.To overcome the defects of a model-free control method,this paper proposes an automatic voltage control(AVC)method for differential power grids based on transfer learning and deep reinforcement learning.First,when constructing the Markov game of AVC,both the magnitude and number of voltage deviations are taken into account in the reward.Then,an AVC method based on constrained multiagent deep reinforcement learning(DRL)is developed.To further improve learning efficiency,domain knowledge is used to reduce action space.Next,distribution adaptation transfer learning is introduced for the AVC transfer circumstance of systems with the same structure but distinct topological relations/parameters,which can perform well without any further training even if the structure changes.Moreover,for the AVC transfer circumstance of various power grids,parameter-based transfer learning is created,which enhances the target system’s training speed and effect.Finally,the method’s efficacy is tested using two IEEE systems and two real-world power grids.
