Extracting typical operational scenarios is essential for making flexible decisions in the dispatch of a new power system.A novel deep time series aggregation scheme(DTSAs)is proposed to generate typical operational s...Extracting typical operational scenarios is essential for making flexible decisions in the dispatch of a new power system.A novel deep time series aggregation scheme(DTSAs)is proposed to generate typical operational scenarios,considering the large amount of historical operational snapshot data.Specifically,DTSAs analyse the intrinsic mechanisms of different scheduling operational scenario switching to mathematically represent typical operational scenarios.A Gramian angular summation field-based operational scenario image encoder was designed to convert operational scenario sequences into highdimensional spaces.This enables DTSAs to fully capture the spatiotemporal characteristics of new power systems using deep feature iterative aggregation models.The encoder also facilitates the generation of typical operational scenarios that conform to historical data distributions while ensuring the integrity of grid operational snapshots.Case studies demonstrate that the proposed method extracted new fine-grained power system dispatch schemes and outperformed the latest high-dimensional feature-screening methods.In addition,experiments with different new energy access ratios were conducted to verify the robustness of the proposed method.DTSAs enable dispatchers to master the operation experience of the power system in advance,and actively respond to the dynamic changes of the operation scenarios under the high access rate of new energy.展开更多
Linguistic single-valued neutrosophic set(LSVNS)is a more reliable tool,which is designed to handle the uncertainties of the situations involving the qualitative data.In the present manuscript,we introduce some power ...Linguistic single-valued neutrosophic set(LSVNS)is a more reliable tool,which is designed to handle the uncertainties of the situations involving the qualitative data.In the present manuscript,we introduce some power aggregation operators(AOs)for the LSVNSs,whose purpose is to diminish the influence of inevitable arguments about the decision-making process.For it,first we develop some averaging power operators,namely,linguistic single-valued neutrosophic(LSVN)power averaging,weighted average,ordered weighted average,and hybrid averaging AOs along with their desirable properties.Further,we extend it to the geometric power AOs for LSVNSs.Based on the proposed work;an approach to solve the group decision-making problems is given along with the numerical example.Finally,a comparative study and the validity tests are present to discuss the reliability of the proposed operators.展开更多
Intuitionistic hesitant fuzzy set(IHFS)is amixture of two separated notions called intuitionistic fuzzy set(IFS)and hesitant fuzzy set(HFS),as an important technique to cope with uncertain and awkward information in r...Intuitionistic hesitant fuzzy set(IHFS)is amixture of two separated notions called intuitionistic fuzzy set(IFS)and hesitant fuzzy set(HFS),as an important technique to cope with uncertain and awkward information in realistic decision issues.IHFS contains the grades of truth and falsity in the formof the subset of the unit interval.The notion of IHFS was defined by many scholars with different conditions,which contain several weaknesses.Here,keeping in view the problems of already defined IHFSs,we will define IHFS in another way so that it becomes compatible with other existing notions.To examine the interrelationship between any numbers of IHFSs,we combined the notions of power averaging(PA)operators and power geometric(PG)operators with IHFSs to present the idea of intuitionistic hesitant fuzzy PA(IHFPA)operators,intuitionistic hesitant fuzzy PG(IHFPG)operators,intuitionistic hesitant fuzzy power weighted average(IHFPWA)operators,intuitionistic hesitant fuzzy power ordered weighted average(IHFPOWA)operators,intuitionistic hesitant fuzzy power ordered weighted geometric(IHFPOWG)operators,intuitionistic hesitant fuzzy power hybrid average(IHFPHA)operators,intuitionistic hesitant fuzzy power hybrid geometric(IHFPHG)operators and examined as well their fundamental properties.Some special cases of the explored work are also discovered.Additionally,the similarity measures based on IHFSs are presented and their advantages are discussed along examples.Furthermore,we initiated a new approach to multiple attribute decision making(MADM)problem applying suggested operators and a mathematical model is solved to develop an approach and to establish its common sense and adequacy.Advantages,comparative analysis,and graphical representation of the presented work are elaborated to show the reliability and effectiveness of the presented works.展开更多
Renewable generation is rapidly increasing and transforming power systems toward“new-type power systems”.The integration of renewable energy resources necessitates a shift from conventional grid-following converters...Renewable generation is rapidly increasing and transforming power systems toward“new-type power systems”.The integration of renewable energy resources necessitates a shift from conventional grid-following converters(GFLs)to advanced grid-forming controls.Although grid-forming converters(GFMs)provide grid support and enhance system stability under weak grid conditions,their deployment requires more robust hardware,complex control algorithms and system operation constraints,resulting in planning and operational trade-offs between system stability and cost efficiency.This paper studies the underexplored question of how many GFMs are needed from a techno-economic perspective.The holistic analysis integrates long-term planning,short-term operational strategies and dynamic stability considerations,thereby supporting large-scale renewable integration while ensuring system security and economic benefits.展开更多
Demand response(DR)is gaining more and more importance in the architecture of power systems in a context of flexible loads and high share of intermittent generation.Changes in electricity markets regulation in several...Demand response(DR)is gaining more and more importance in the architecture of power systems in a context of flexible loads and high share of intermittent generation.Changes in electricity markets regulation in several countries have recently enabled an effective integration of DR mechanisms in power systems.Through its flexible components(pumps,tanks),drinking water systems are suitable candidates for energy-efficient DR mechanisms.However,these systems are often managed independently of power system operation for both economic and operational reasons.Indeed,a sufficient level of economic viability and water demands risk management are necessary for water utilities to integrate their flexibilities to power system operation.In this paper,we proposed a mathematical model for optimizing pump schedules in water systems while trading DR blocs in a spot power market during peak times.Uncertainties about water demands were considered in the mathematical model allowing to propose power reductions covering the potential risk of real-time water demand forecasting inaccuracy.Numerical results were discussed on a real water system in France,demonstrating both economic and ecological benefits.展开更多
We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. Fo...We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. For a 2-mm-long and 10-μm-wide laser coated with high-reflectivity on the rear facet, more than 170mW of output power is obtained at 20℃ with a threshold power consumption of 2.4 W, corresponding to 30mW with a threshold power consumption of 3.9 W at 90℃. Robust single-mode emission with a side-mode suppression ratio above 25 dB is continuously tunable by the heat sink temperature or injection current.展开更多
As the scale of the power system continues to expand,the environment for power operations becomes more and more complex.Existing risk management and control methods for power operations can only set the same risk dete...As the scale of the power system continues to expand,the environment for power operations becomes more and more complex.Existing risk management and control methods for power operations can only set the same risk detection standard and conduct the risk detection for any scenario indiscriminately.Therefore,more reliable and accurate security control methods are urgently needed.In order to improve the accuracy and reliability of the operation risk management and control method,this paper proposes a method for identifying the key links in the whole process of electric power operation based on the spatiotemporal hybrid convolutional neural network.To provide early warning and control of targeted risks,first,the video stream is framed adaptively according to the pixel changes in the video stream.Then,the optimized MobileNet is used to extract the feature map of the video stream,which contains both time-series and static spatial scene information.The feature maps are combined and non-linearly mapped to realize the identification of dynamic operating scenes.Finally,training samples and test samples are produced by using the whole process image of a power company in Xinjiang as a case study,and the proposed algorithm is compared with the unimproved MobileNet.The experimental results demonstrated that the method proposed in this paper can accurately identify the type and start and end time of each operation link in the whole process of electric power operation,and has good real-time performance.The average accuracy of the algorithm can reach 87.8%,and the frame rate is 61 frames/s,which is of great significance for improving the reliability and accuracy of security control methods.展开更多
A necessary and sufficient condition for the generalized shift operator T=S-k-(a(1)((1)),a(2)((1)),...)x e(1)-...-(a(1)((j)),a(2)((j)),...)x e(j)(j greater than or equal to k)on l(1)to be power bounded is obtained.Mor...A necessary and sufficient condition for the generalized shift operator T=S-k-(a(1)((1)),a(2)((1)),...)x e(1)-...-(a(1)((j)),a(2)((j)),...)x e(j)(j greater than or equal to k)on l(1)to be power bounded is obtained.Moreover,this note points out that the power bounded operator T=S-(1,1,...)x c(1)can shift a basis of[e(j+1)-e(j)](j=1)(infinity),and this basis is not equivalent to{T(n)e(1)}(infinity)(n=0).展开更多
In this study, particular matrices which is called P-matrices were defined for the action of the Steenrod powers on the polynomial algebra and it was shown that they can be used to calculate the action of Steenrod pow...In this study, particular matrices which is called P-matrices were defined for the action of the Steenrod powers on the polynomial algebra and it was shown that they can be used to calculate the action of Steenrod powers on product of two generators. Finally an algorithm was given to obtain these matrices.展开更多
For strictly positive operators A and B, and for x ∈ [0,1] and r ∈[-1,1], we investigate the operator power mean A#x,rB=A1/2{（1-x）/＋x（a-1＊2BA-1/2）r}1/rA1/2 If r = O, this is reduced to the geometric operator m...For strictly positive operators A and B, and for x ∈ [0,1] and r ∈[-1,1], we investigate the operator power mean A#x,rB=A1/2{（1-x）/＋x（a-1＊2BA-1/2）r}1/rA1/2 If r = O, this is reduced to the geometric operator mean A#x,rB=A1/2{（1-x）/＋x（a-1＊2BA-1/2）r}1/rA1/2 Since A #0,r B = A and A #l,r B = B, weregard A#t,rB as apath combining A and B.Our aim is to show the essential properties of St,r （AIB）. The Tsallis relative operator entropy by Yanagi, Kuriyama and Furuichi can also be expanded, and by using this, we can give an expanded operator valued a-divergence and obtain its properties.展开更多
For Chinese power enterprises,investing overseas and actively seeking international cooperation in energy resources for mutual benefit accords with not only the desires of themselves to become bigger and stronger,but ...For Chinese power enterprises,investing overseas and actively seeking international cooperation in energy resources for mutual benefit accords with not only the desires of themselves to become bigger and stronger,but also China's energy strategy. Having won the first overseas state-level power-grid operation right,the State Grid Corporation of China (SGCC) took the lead in carrying out the strategy of "going out."展开更多
In the operation process of the power plant, the boiler is the most important equipment, and the boiler operation consumes a lot of energy and increases the burden of the enterprises. In order to comprehensively impro...In the operation process of the power plant, the boiler is the most important equipment, and the boiler operation consumes a lot of energy and increases the burden of the enterprises. In order to comprehensively improve the environmental level and ensure the economic benefits of enterprises, we should advocate the concept of energy conservation in the whole society, and do a good job in the overall economic structural adjustment, so as to promote the rapid economic development. The problem of energy saving and consumption reduction in power plant boilers has attracted wide attention. Through the scientific and reasonable application of energy saving and consumption reduction technology, it can greatly save energy, reduce environmental pollution, but also improve the overall efficiency of power plants, and promote the healthy development of power plants.展开更多
The national standard--Safety Specifications for Power Driven VehiclesOperating on Roads--is the most basic technical regulation for safety and technical management ofmotor vehicles in China. It is the safety and tech...The national standard--Safety Specifications for Power Driven VehiclesOperating on Roads--is the most basic technical regulation for safety and technical management ofmotor vehicles in China. It is the safety and technical basis for the Public Security TrafficControl Dept. to register new vehicles, periodic inspection of vehicles under operation andinspection of vehicles involved in traffic accidents. It is also one of the important technicalbases of our country for compulsory inspection of new vehicles on fi-nalization of its model,ex-works inspection of new vehicles and the inspection of imported motor vehicles. Since the formalcountrywide implementation of GB7258-1997 Safety Specifications for Power Driven Vehicles Operatingon Roads on Jan. 1, 1998, the standard has played a very active role in strengthening the operatingsafety management of motor vehicles, improving the operating safety level of motor vehicles, and insafeguarding road traffic safety, etc. However, along with the rapid and sustainable growth of ournational economy, the number of motor vehicles has increased rapidly, especially privately-ownedautomobiles, so that the incidence of road traffic accidents rises yearly and the road trafficsafety situation is becoming increasingly serious. Therefore, the General Administration of QualitySupervision, Inspection and Quarantine of the People's Republic of China (AQSIQ) and theStandardization Administration of China (SAC) have issued the revised standard GB725 8-2004 SafetySpecifications for Power Driven Vehicles Operating on Roads, which will be put into effect onOctober 1, 2004. The timely revision of this standard is very necessary for upgrading the safety andtechnical requirements for motor vehicles in China.展开更多
Electric power, as one of the basic elements of social operation, promotes the economic development of various places, and the importance of power plants is self-evident. Whether the power plant can work efficiently a...Electric power, as one of the basic elements of social operation, promotes the economic development of various places, and the importance of power plants is self-evident. Whether the power plant can work efficiently and maintain the quality of output will affect the stability of power. So the safety of power plant must be paid attention to. In safety management, we should pay special attention to the emergency problems. We should prepare the corresponding countermeasures to solve the unexpected accidents and minimize the losses. This kind of safety management is complete enough to ensure the safe operation of the power plant.展开更多
On January 6, the National Energy Administration released the operational indices of Chinese power industry in 2009, including total consumption, capital construction investment and the capacity of
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
Driven by the desire of a low-carbon society,the penetration level of renewable generation in the power grid of China will still grow fast in the near future.As the synchronised generators whose output is controllable...Driven by the desire of a low-carbon society,the penetration level of renewable generation in the power grid of China will still grow fast in the near future.As the synchronised generators whose output is controllable are gradually replaced by volatile energy resources,energy storage is expected to play a vital role in regulation services and flexibility provision.Because the capital cost of energy storage is still relatively high,it is important to assess the value or demand of energy storage before making an investment decision.This paper presents two representative mathematical tools to achieve this target in a geometric fashion.The first one is the multi-parametric programming method.It depicts the reduced cost by deploying energy storage through post-optimal value function,which is easy to visualise or can be embedded in high-level optimisation problems such as storage sizing.The second one is a polyhedral projection method.It represents all feasible power-energy capacity pairs of a storage unit to achieve a certain target.The above methods remove the need of repeatedly solving a large number of problems with varying capacity parameters.Simple examples are given for illustration,and the presented methods can also directly handle problems with complex models and constraints.展开更多
基金The Key R&D Project of Jilin Province,Grant/Award Number:20230201067GX。
文摘Extracting typical operational scenarios is essential for making flexible decisions in the dispatch of a new power system.A novel deep time series aggregation scheme(DTSAs)is proposed to generate typical operational scenarios,considering the large amount of historical operational snapshot data.Specifically,DTSAs analyse the intrinsic mechanisms of different scheduling operational scenario switching to mathematically represent typical operational scenarios.A Gramian angular summation field-based operational scenario image encoder was designed to convert operational scenario sequences into highdimensional spaces.This enables DTSAs to fully capture the spatiotemporal characteristics of new power systems using deep feature iterative aggregation models.The encoder also facilitates the generation of typical operational scenarios that conform to historical data distributions while ensuring the integrity of grid operational snapshots.Case studies demonstrate that the proposed method extracted new fine-grained power system dispatch schemes and outperformed the latest high-dimensional feature-screening methods.In addition,experiments with different new energy access ratios were conducted to verify the robustness of the proposed method.DTSAs enable dispatchers to master the operation experience of the power system in advance,and actively respond to the dynamic changes of the operation scenarios under the high access rate of new energy.
文摘Linguistic single-valued neutrosophic set(LSVNS)is a more reliable tool,which is designed to handle the uncertainties of the situations involving the qualitative data.In the present manuscript,we introduce some power aggregation operators(AOs)for the LSVNSs,whose purpose is to diminish the influence of inevitable arguments about the decision-making process.For it,first we develop some averaging power operators,namely,linguistic single-valued neutrosophic(LSVN)power averaging,weighted average,ordered weighted average,and hybrid averaging AOs along with their desirable properties.Further,we extend it to the geometric power AOs for LSVNSs.Based on the proposed work;an approach to solve the group decision-making problems is given along with the numerical example.Finally,a comparative study and the validity tests are present to discuss the reliability of the proposed operators.
基金supported by“Algebra and Applications Research Unit,Division of Computational Science,Faculty of Science,Prince of Songkla University”.
文摘Intuitionistic hesitant fuzzy set(IHFS)is amixture of two separated notions called intuitionistic fuzzy set(IFS)and hesitant fuzzy set(HFS),as an important technique to cope with uncertain and awkward information in realistic decision issues.IHFS contains the grades of truth and falsity in the formof the subset of the unit interval.The notion of IHFS was defined by many scholars with different conditions,which contain several weaknesses.Here,keeping in view the problems of already defined IHFSs,we will define IHFS in another way so that it becomes compatible with other existing notions.To examine the interrelationship between any numbers of IHFSs,we combined the notions of power averaging(PA)operators and power geometric(PG)operators with IHFSs to present the idea of intuitionistic hesitant fuzzy PA(IHFPA)operators,intuitionistic hesitant fuzzy PG(IHFPG)operators,intuitionistic hesitant fuzzy power weighted average(IHFPWA)operators,intuitionistic hesitant fuzzy power ordered weighted average(IHFPOWA)operators,intuitionistic hesitant fuzzy power ordered weighted geometric(IHFPOWG)operators,intuitionistic hesitant fuzzy power hybrid average(IHFPHA)operators,intuitionistic hesitant fuzzy power hybrid geometric(IHFPHG)operators and examined as well their fundamental properties.Some special cases of the explored work are also discovered.Additionally,the similarity measures based on IHFSs are presented and their advantages are discussed along examples.Furthermore,we initiated a new approach to multiple attribute decision making(MADM)problem applying suggested operators and a mathematical model is solved to develop an approach and to establish its common sense and adequacy.Advantages,comparative analysis,and graphical representation of the presented work are elaborated to show the reliability and effectiveness of the presented works.
基金supported in part by the Carbon Neutrality and Energy System Transformation project and in part by EPSRC under Grant EP/Y025946/1.
文摘Renewable generation is rapidly increasing and transforming power systems toward“new-type power systems”.The integration of renewable energy resources necessitates a shift from conventional grid-following converters(GFLs)to advanced grid-forming controls.Although grid-forming converters(GFMs)provide grid support and enhance system stability under weak grid conditions,their deployment requires more robust hardware,complex control algorithms and system operation constraints,resulting in planning and operational trade-offs between system stability and cost efficiency.This paper studies the underexplored question of how many GFMs are needed from a techno-economic perspective.The holistic analysis integrates long-term planning,short-term operational strategies and dynamic stability considerations,thereby supporting large-scale renewable integration while ensuring system security and economic benefits.
文摘Demand response(DR)is gaining more and more importance in the architecture of power systems in a context of flexible loads and high share of intermittent generation.Changes in electricity markets regulation in several countries have recently enabled an effective integration of DR mechanisms in power systems.Through its flexible components(pumps,tanks),drinking water systems are suitable candidates for energy-efficient DR mechanisms.However,these systems are often managed independently of power system operation for both economic and operational reasons.Indeed,a sufficient level of economic viability and water demands risk management are necessary for water utilities to integrate their flexibilities to power system operation.In this paper,we proposed a mathematical model for optimizing pump schedules in water systems while trading DR blocs in a spot power market during peak times.Uncertainties about water demands were considered in the mathematical model allowing to propose power reductions covering the potential risk of real-time water demand forecasting inaccuracy.Numerical results were discussed on a real water system in France,demonstrating both economic and ecological benefits.
基金Supported by the National Basic Research Program of China under Grant No 2013CB632801the National Key Research and Development Program under Grant No 2016YFB0402303+2 种基金the National Natural Science Foundation of China under Grant Nos61435014,61627822,61574136 and 61306058the Key Projects of Chinese Academy of Sciences under Grant No ZDRW-XH-2016-4the Beijing Natural Science Foundation under Grant No 4162060
文摘We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. For a 2-mm-long and 10-μm-wide laser coated with high-reflectivity on the rear facet, more than 170mW of output power is obtained at 20℃ with a threshold power consumption of 2.4 W, corresponding to 30mW with a threshold power consumption of 3.9 W at 90℃. Robust single-mode emission with a side-mode suppression ratio above 25 dB is continuously tunable by the heat sink temperature or injection current.
基金This paper is supported by the Science and technology projects of Yunnan Province(Grant No.202202AD080004).
文摘As the scale of the power system continues to expand,the environment for power operations becomes more and more complex.Existing risk management and control methods for power operations can only set the same risk detection standard and conduct the risk detection for any scenario indiscriminately.Therefore,more reliable and accurate security control methods are urgently needed.In order to improve the accuracy and reliability of the operation risk management and control method,this paper proposes a method for identifying the key links in the whole process of electric power operation based on the spatiotemporal hybrid convolutional neural network.To provide early warning and control of targeted risks,first,the video stream is framed adaptively according to the pixel changes in the video stream.Then,the optimized MobileNet is used to extract the feature map of the video stream,which contains both time-series and static spatial scene information.The feature maps are combined and non-linearly mapped to realize the identification of dynamic operating scenes.Finally,training samples and test samples are produced by using the whole process image of a power company in Xinjiang as a case study,and the proposed algorithm is compared with the unimproved MobileNet.The experimental results demonstrated that the method proposed in this paper can accurately identify the type and start and end time of each operation link in the whole process of electric power operation,and has good real-time performance.The average accuracy of the algorithm can reach 87.8%,and the frame rate is 61 frames/s,which is of great significance for improving the reliability and accuracy of security control methods.
基金the Education Department Foundation of Henan province.
文摘A necessary and sufficient condition for the generalized shift operator T=S-k-(a(1)((1)),a(2)((1)),...)x e(1)-...-(a(1)((j)),a(2)((j)),...)x e(j)(j greater than or equal to k)on l(1)to be power bounded is obtained.Moreover,this note points out that the power bounded operator T=S-(1,1,...)x c(1)can shift a basis of[e(j+1)-e(j)](j=1)(infinity),and this basis is not equivalent to{T(n)e(1)}(infinity)(n=0).
文摘In this study, particular matrices which is called P-matrices were defined for the action of the Steenrod powers on the polynomial algebra and it was shown that they can be used to calculate the action of Steenrod powers on product of two generators. Finally an algorithm was given to obtain these matrices.
文摘For strictly positive operators A and B, and for x ∈ [0,1] and r ∈[-1,1], we investigate the operator power mean A#x,rB=A1/2{（1-x）/＋x（a-1＊2BA-1/2）r}1/rA1/2 If r = O, this is reduced to the geometric operator mean A#x,rB=A1/2{（1-x）/＋x（a-1＊2BA-1/2）r}1/rA1/2 Since A #0,r B = A and A #l,r B = B, weregard A#t,rB as apath combining A and B.Our aim is to show the essential properties of St,r （AIB）. The Tsallis relative operator entropy by Yanagi, Kuriyama and Furuichi can also be expanded, and by using this, we can give an expanded operator valued a-divergence and obtain its properties.
文摘For Chinese power enterprises,investing overseas and actively seeking international cooperation in energy resources for mutual benefit accords with not only the desires of themselves to become bigger and stronger,but also China's energy strategy. Having won the first overseas state-level power-grid operation right,the State Grid Corporation of China (SGCC) took the lead in carrying out the strategy of "going out."
文摘In the operation process of the power plant, the boiler is the most important equipment, and the boiler operation consumes a lot of energy and increases the burden of the enterprises. In order to comprehensively improve the environmental level and ensure the economic benefits of enterprises, we should advocate the concept of energy conservation in the whole society, and do a good job in the overall economic structural adjustment, so as to promote the rapid economic development. The problem of energy saving and consumption reduction in power plant boilers has attracted wide attention. Through the scientific and reasonable application of energy saving and consumption reduction technology, it can greatly save energy, reduce environmental pollution, but also improve the overall efficiency of power plants, and promote the healthy development of power plants.
文摘The national standard--Safety Specifications for Power Driven VehiclesOperating on Roads--is the most basic technical regulation for safety and technical management ofmotor vehicles in China. It is the safety and technical basis for the Public Security TrafficControl Dept. to register new vehicles, periodic inspection of vehicles under operation andinspection of vehicles involved in traffic accidents. It is also one of the important technicalbases of our country for compulsory inspection of new vehicles on fi-nalization of its model,ex-works inspection of new vehicles and the inspection of imported motor vehicles. Since the formalcountrywide implementation of GB7258-1997 Safety Specifications for Power Driven Vehicles Operatingon Roads on Jan. 1, 1998, the standard has played a very active role in strengthening the operatingsafety management of motor vehicles, improving the operating safety level of motor vehicles, and insafeguarding road traffic safety, etc. However, along with the rapid and sustainable growth of ournational economy, the number of motor vehicles has increased rapidly, especially privately-ownedautomobiles, so that the incidence of road traffic accidents rises yearly and the road trafficsafety situation is becoming increasingly serious. Therefore, the General Administration of QualitySupervision, Inspection and Quarantine of the People's Republic of China (AQSIQ) and theStandardization Administration of China (SAC) have issued the revised standard GB725 8-2004 SafetySpecifications for Power Driven Vehicles Operating on Roads, which will be put into effect onOctober 1, 2004. The timely revision of this standard is very necessary for upgrading the safety andtechnical requirements for motor vehicles in China.
文摘Electric power, as one of the basic elements of social operation, promotes the economic development of various places, and the importance of power plants is self-evident. Whether the power plant can work efficiently and maintain the quality of output will affect the stability of power. So the safety of power plant must be paid attention to. In safety management, we should pay special attention to the emergency problems. We should prepare the corresponding countermeasures to solve the unexpected accidents and minimize the losses. This kind of safety management is complete enough to ensure the safe operation of the power plant.
文摘On January 6, the National Energy Administration released the operational indices of Chinese power industry in 2009, including total consumption, capital construction investment and the capacity of
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.
基金supported by the National Key Research and Development Programme of China(2021YFB2400701).
文摘Driven by the desire of a low-carbon society,the penetration level of renewable generation in the power grid of China will still grow fast in the near future.As the synchronised generators whose output is controllable are gradually replaced by volatile energy resources,energy storage is expected to play a vital role in regulation services and flexibility provision.Because the capital cost of energy storage is still relatively high,it is important to assess the value or demand of energy storage before making an investment decision.This paper presents two representative mathematical tools to achieve this target in a geometric fashion.The first one is the multi-parametric programming method.It depicts the reduced cost by deploying energy storage through post-optimal value function,which is easy to visualise or can be embedded in high-level optimisation problems such as storage sizing.The second one is a polyhedral projection method.It represents all feasible power-energy capacity pairs of a storage unit to achieve a certain target.The above methods remove the need of repeatedly solving a large number of problems with varying capacity parameters.Simple examples are given for illustration,and the presented methods can also directly handle problems with complex models and constraints.
