Since the founding of the People's Republic of China in 1949, China's global energy strategy has experienced three stages: "infancy", "growth" and "maturity". Chinese foreign ener...Since the founding of the People's Republic of China in 1949, China's global energy strategy has experienced three stages: "infancy", "growth" and "maturity". Chinese foreign energy cooperation has also gone through three periods chronologically, which include(1) the period when China got rid of its high dependence on oil imports from the Soviet Union, achieved self-reliance and even became a net exporter;(2) the period when China first focused on "bringing in" and then turned itself into a net importer of crude oil and refined oil; and(3) the period when China "went global" to engage in energy cooperation in diverse areas, gradually shifting into a leading role before launching the Belt and Road Initiative, which marked the full establishment of the Chinese global energy strategy. The objective of the Chinese global energy strategy has gradually changed from merely pursuing "energy strength" to transforming "energy strength" into "energy power"; the mission is mainly to "promote energy cooperation and energy revolution"; to implement this mission, China will provide international public goods to global and regional energy governance through energy diplomacy and services; and the areas covered by the strategy are countries and regions along the "Silk Road Economic Belt".展开更多
A threat of global warming should convince the public to accept a nuclear fission energy contribution to climate change mitigation, at least for the climate critical years up to 2065. The nuclear fission energy is ava...A threat of global warming should convince the public to accept a nuclear fission energy contribution to climate change mitigation, at least for the climate critical years up to 2065. The nuclear fission energy is available now, with proven reactors, such as advanced LWR (light water reactors). Nuclear strategy in this paper outlines a proposal to replace all coal power plants (without carbon and capture storage system) with nuclear power plants in the period 2025-2065. Assuming once through advanced LWR technology, one would need nuclear capacity of 1,600 GW to replace coal power plants in that period. Corresponding reduction of emission would amount to 11.8 Gt of CO2. This energy strategy would reduce carbon emission by approximately 22% in the year 2065 and would be covered by projected uranium resources. An estimation of replacement costs showed that future carbon tax has a considerable potential to offset higher costs of nuclear replacement power.展开更多
The new energy vehicle plays a crucial role in green transportation,and the energy management strategy of hybrid power systems is essential for ensuring energy-efficient driving.This paper presents a state-of-the-art ...The new energy vehicle plays a crucial role in green transportation,and the energy management strategy of hybrid power systems is essential for ensuring energy-efficient driving.This paper presents a state-of-the-art survey and review of reinforcement learning-based energy management strategies for hybrid power systems.Additionally,it envisions the outlook for autonomous intelligent hybrid electric vehicles,with reinforcement learning as the foundational technology.First of all,to provide a macro view of historical development,the brief history of deep learning,reinforcement learning,and deep reinforcement learning is presented in the form of a timeline.Then,the comprehensive survey and review are conducted by collecting papers from mainstream academic databases.Enumerating most of the contributions based on three main directions—algorithm innovation,powertrain innovation,and environment innovation—provides an objective review of the research status.Finally,to advance the application of reinforcement learning in autonomous intelligent hybrid electric vehicles,future research plans positioned as“Alpha HEV”are envisioned,integrating Autopilot and energy-saving control.展开更多
The plug-in hybrid vehicles(PHEV)technology can effectively address the issues of poor dynamics and higher energy consumption commonly found in traditional mining dump trucks.Meanwhile,plug-in hybrid electric trucks c...The plug-in hybrid vehicles(PHEV)technology can effectively address the issues of poor dynamics and higher energy consumption commonly found in traditional mining dump trucks.Meanwhile,plug-in hybrid electric trucks can achieve excellent fuel economy through efficient energy management strategies(EMS).Therefore,a series hybrid system is constructed based on a 100-ton mining dump truck in this paper.And inspired by the dynamic programming(DP)algorithm,a predictive equivalent consumption minimization strategy(P-ECMS)based on the DP optimization result is proposed.Based on the optimal control manifold and the SOC reference trajectory obtained by the DP algorithm,the P-ECMS strategy performs real-time stage parameter optimization to obtain the optimal equivalent factor(EF).Finally,applying the equivalent consumption minimization strategy(ECMS)realizes real-time control.The simulation results show that the equivalent fuel consumption of the P-ECMS strategy under the experimentally collected mining cycle conditions is 150.8 L/100 km,which is 10.9%less than that of the common CDCS strategy(169.3 L/100 km),and achieves 99.47%of the fuel saving effect of the DP strategy(150 L/100 km).展开更多
China's energy demand and energy imports have increased substantially in recent 5 years and will continue to grow in future. Increasing dependency on the world market and the tension between energy supply and demand ...China's energy demand and energy imports have increased substantially in recent 5 years and will continue to grow in future. Increasing dependency on the world market and the tension between energy supply and demand clearly show that energy is becoming a major constraint for China's future economic development. We introduce the background of China's energy demand and supply in this paper and discuss China's energy strategy in the twentyfirst century, focusing on growth, energy security and environmental sustainability.展开更多
“Those who owns the Middle East oil,will have the world.”The world’s major energy consumers-the United States and Russia holding the“energy card”meet in the Middle East.There are consensus and also contradictions...“Those who owns the Middle East oil,will have the world.”The world’s major energy consumers-the United States and Russia holding the“energy card”meet in the Middle East.There are consensus and also contradictions in their energy strategies and interests.Based on the comparison between the energy strategy and policy of the two countries,this article aims to provide their experience in the Middle East for China to think and learn.展开更多
In face of challenges to its energy security,China has been making adjustments in its energy policy and energy development strategy since mid-1990s,and implementing a strategy for overseas energy development.Compared ...In face of challenges to its energy security,China has been making adjustments in its energy policy and energy development strategy since mid-1990s,and implementing a strategy for overseas energy development.Compared with Central Asia,Latin America,Southeast Asia and West Africa,the Middle East is still the major source for China’s overseas energy cooperation and development.To avoid over-dependence on the energy resources in the Middle East,China seeks more overseas energy sources and transportation channels other than those in or connected to the Middle East.However,the primary role of the Middle East in China’s overall strategy for overseas energy development is still irreplaceable by that of any other region,at least for the near future.This situation will surely produce an increasingly important impact on China’s Middle East policy,moving China to take a more active posture in the political and economic arena of the region.It can even be expected that China to maintain its stable and friendly relations with Middle East countries,will,more likely than ever,act as a diplomatic mediator in trying to resolve certain longstanding conflicts in the region.展开更多
Energy management strategy (EMS) is the core of the real-time controlalgorithm of the hybrid electric vehicle (HEV). A novel EMS using the logic threshold approach withincorporation of a stand-by optimization algorith...Energy management strategy (EMS) is the core of the real-time controlalgorithm of the hybrid electric vehicle (HEV). A novel EMS using the logic threshold approach withincorporation of a stand-by optimization algorithm is proposed. The aim of it is to minimize theengine fuel consumption and maintain the battery state of charge (SOC) in its operation range, whilesatisfying the vehicle performance and drivability requirements. The hybrid powertrain bench testis carried out to collect data of the engine, motor and battery pack, which are used in the EMS tocontrol the powertrain. Computer simulation model of the HEV is established in the MATLAB/Simulinkenvironment according to the bench test results. Simulation results are presented for behaviors ofthe engine, motor and battery. The proposed EMS is implemented for a real parallel hybrid carcontrol system and validated by vehicle field tests.展开更多
A novel parallel hybrid electrical urban bus (PHEUB) configuration consisting of an extra one-way clutch and an automatic mechanical transmission (AMT) is taken as the study subject. An energy management strategy ...A novel parallel hybrid electrical urban bus (PHEUB) configuration consisting of an extra one-way clutch and an automatic mechanical transmission (AMT) is taken as the study subject. An energy management strategy combining a logic threshold approach and an instantaneous optimization algorithm is proposed for the investigated PHEUB. The objective of the energy management strategy is to achieve acceptable vehicle performance and drivability requirements while simultaneously maximizing the engine fuel consumption and maintaining the battery state of charge in its operation range at all times. Under the environment of Matlab/Simulink, a computer simulation model for the PHEUB is constructed by using the model building method combining theoretical analysis and bench test data. Simulation and experiment results for China Typical Bus Driving Schedule at Urban District (CTBDS_UD) are obtained, and the results indicate that the proposed control strategy not only controls the hybrid system efficiently but also improves the fuel economy significantly.展开更多
In this paper, a plug-in hybrid electrical vehicle(PHEV) is taken as the research object, and its dynamic performance and economic performance are taken as the research goals. Battery charge-sustaining(CS) period is d...In this paper, a plug-in hybrid electrical vehicle(PHEV) is taken as the research object, and its dynamic performance and economic performance are taken as the research goals. Battery charge-sustaining(CS) period is divided into power mode and economy mode. Energy management strategy designing methods of power mode and economy mode are proposed. Maximum velocity, acceleration performance and fuel consumption are simulated during the CS period in the AVL CRUISE simulation environment. The simulation results indicate that the maximum velocity and acceleration time of the power mode are better than those in the economy mode. Fuel consumption of the economy mode is better than that in the power mode. Fuel consumption of PHEV during the CS period is further improved by using the methods proposed in this paper, and this is meaningful for research and development of PHEV.展开更多
Aimed at the relatively lower energy density and complicated coordinating operation between two power sources,a special energy control strategy is required to maximize the fuel saving potential.Then a new type of conf...Aimed at the relatively lower energy density and complicated coordinating operation between two power sources,a special energy control strategy is required to maximize the fuel saving potential.Then a new type of configuration for hydrostatic transmission hybrid vehicles(PHHV) and the selection criterion for important components are proposed.Based on the optimization of planet gear transmission ratio and the analysis of optimal energy distribution for the proposed PHHV on a representative urban driving cycle,a fuzzy torque control strategy and a braking energy regeneration strategy are designed and developed to realize the real-time control of energy for the proposed PHHV.Simulation results demonstrate that the energy control strategy effectively improves the fuel economy of PHHV.展开更多
The flux-modulated compound-structure permanent magnet synchronous machine (CS-PMSM), composed of a brushless double rotor machine (DRM) and a conventional permanent magnet synchronous machine (PMSM), is a power split...The flux-modulated compound-structure permanent magnet synchronous machine (CS-PMSM), composed of a brushless double rotor machine (DRM) and a conventional permanent magnet synchronous machine (PMSM), is a power split device for plug-in hybrid electric vehicles. In this paper, its operating principle and mathematical model are introduced. A modified current controller with decoupled state feedback is proposed and verified. The system control strategy is simulated in Matlab, and the feasibility of the control system is proven. To improve fuel economy, an energy management strategy based on fuzzy logic controller is proposed and evaluated by the Urban Dynamometer Driving Schedule (UDDS) drive cycle. The results show that the total energy consumption is similar to that of Prius 2012.展开更多
This paper proposes an energy management strategy for a fuel cell(FC)hybrid power system based on dynamic programming and state machine strategy,which takes into account the durability of the FC and the hydrogen consu...This paper proposes an energy management strategy for a fuel cell(FC)hybrid power system based on dynamic programming and state machine strategy,which takes into account the durability of the FC and the hydrogen consumption of the system.The strategy first uses the principle of dynamic programming to solve the optimal power distribution between the FC and supercapacitor(SC),and then uses the optimization results of dynamic programming to update the threshold values in each state of the finite state machine to realize real-time management of the output power of the FC and SC.An FC/SC hybrid tramway simulation platform is established based on RTLAB real-time simulator.The compared results verify that the proposed EMS can improve the durability of the FC,increase its working time in the high-efficiency range,effectively reduce the hydrogen consumption,and keep the state of charge in an ideal range.展开更多
Capacity allocation and energy management strategies for energy storage are critical to the safety and economical operation of microgrids.In this paper,an improved energymanagement strategy based on real-time electric...Capacity allocation and energy management strategies for energy storage are critical to the safety and economical operation of microgrids.In this paper,an improved energymanagement strategy based on real-time electricity price combined with state of charge is proposed to optimize the economic operation of wind and solar microgrids,and the optimal allocation of energy storage capacity is carried out by using this strategy.Firstly,the structure and model of microgrid are analyzed,and the outputmodel of wind power,photovoltaic and energy storage is established.Then,considering the interactive power cost between the microgrid and the main grid and the charge-discharge penalty cost of energy storage,an optimization objective function is established,and an improved energy management strategy is proposed on this basis.Finally,a physicalmodel is built inMATLAB/Simulink for simulation verification,and the energy management strategy is compared and analyzed on sunny and rainy days.The initial configuration cost function of energy storage is added to optimize the allocation of energy storage capacity.The simulation results show that the improved energy management strategy can make the battery charge-discharge response to real-time electricity price and state of charge better than the traditional strategy on sunny or rainy days,reduce the interactive power cost between the microgrid system and the power grid.After analyzing the change of energy storage power with cost,we obtain the best energy storage capacity and energy storage power.展开更多
In 1949, the Chinese energy industry had an annual output of 20 million tons of standard coal equivalent, which was relatively small. The energy industry has developed at a rapid rate since the 1950s. Some statistics ...In 1949, the Chinese energy industry had an annual output of 20 million tons of standard coal equivalent, which was relatively small. The energy industry has developed at a rapid rate since the 1950s. Some statistics show that the annual production of coal in 1990 increased 34 times and the annual production of electricity in 1990 increased 140 times compared to 1949. The annual output of energy reached one billion standard coal equivalent in 1990 and 1.24 billion in 1995. Although China has become a big country for energy production, the energy supply does not yet meet the needs of its economic development. This situation first展开更多
I. Preface
Biomass includes the residues of agriculture, forest and stock breeding, as well as straw, algae and energy crops. In its broad meaning, biomass is a kind of organic matter produced by the photosynthesis of...I. Preface
Biomass includes the residues of agriculture, forest and stock breeding, as well as straw, algae and energy crops. In its broad meaning, biomass is a kind of organic matter produced by the photosynthesis of plants, which is not only renewable, but also contains plentiful energy.展开更多
This paper uses the minimization and weighted sum of battery capacity loss and energy consumption under driving cycles as objective functions to improve the economy of Electric Vehicles(EVs)with an hybrid energy stora...This paper uses the minimization and weighted sum of battery capacity loss and energy consumption under driving cycles as objective functions to improve the economy of Electric Vehicles(EVs)with an hybrid energy storage system composed of power batteries and ultracapacitors.Furthermore,Dynamic Programming(DP)is employed to determine the objective function values under different weight coefficients,the comprehensive cost consisting of battery aging and power consumption costs,and the relationship between the hybrid power distribution.We also evaluate the real-time fuzzy Energy Management Strategy(EMS),fuzzy control strategies,and a strategy based on DP using the World Light vehicle Test Procedure(WLTP)driving cycle and a synthesis driving cycle derived from New European Driving Cycle(NEDC),WLTP,and Urban Dynamometer Driving Schedule(UDDS)as examples.Then,the proposed strategy is compared with the fuzzy control strategy and the strategy based on DP.Compared with fuzzy energy management strategy(namely FZY-EMS),the proposed EMS reduces the battery capacity loss and system energy consumption.The results demonstrate the effectiveness of the proposed EMS in improving EV economy.展开更多
With the heavy dependence of world's growing economy on energy supply, the energy issue again comes into the spotlight throughout the world. How to ensure energy security is a great concern to most countries in the w...With the heavy dependence of world's growing economy on energy supply, the energy issue again comes into the spotlight throughout the world. How to ensure energy security is a great concern to most countries in the world. In this paper, trends in energy supply, energy security mechanism and new challenges are analyzed. As well as, China's security strategies are also proposed.展开更多
文摘Since the founding of the People's Republic of China in 1949, China's global energy strategy has experienced three stages: "infancy", "growth" and "maturity". Chinese foreign energy cooperation has also gone through three periods chronologically, which include(1) the period when China got rid of its high dependence on oil imports from the Soviet Union, achieved self-reliance and even became a net exporter;(2) the period when China first focused on "bringing in" and then turned itself into a net importer of crude oil and refined oil; and(3) the period when China "went global" to engage in energy cooperation in diverse areas, gradually shifting into a leading role before launching the Belt and Road Initiative, which marked the full establishment of the Chinese global energy strategy. The objective of the Chinese global energy strategy has gradually changed from merely pursuing "energy strength" to transforming "energy strength" into "energy power"; the mission is mainly to "promote energy cooperation and energy revolution"; to implement this mission, China will provide international public goods to global and regional energy governance through energy diplomacy and services; and the areas covered by the strategy are countries and regions along the "Silk Road Economic Belt".
文摘A threat of global warming should convince the public to accept a nuclear fission energy contribution to climate change mitigation, at least for the climate critical years up to 2065. The nuclear fission energy is available now, with proven reactors, such as advanced LWR (light water reactors). Nuclear strategy in this paper outlines a proposal to replace all coal power plants (without carbon and capture storage system) with nuclear power plants in the period 2025-2065. Assuming once through advanced LWR technology, one would need nuclear capacity of 1,600 GW to replace coal power plants in that period. Corresponding reduction of emission would amount to 11.8 Gt of CO2. This energy strategy would reduce carbon emission by approximately 22% in the year 2065 and would be covered by projected uranium resources. An estimation of replacement costs showed that future carbon tax has a considerable potential to offset higher costs of nuclear replacement power.
基金Supported by National Natural Science Foundation of China (Grant Nos.52222215,52072051)Fundamental Research Funds for the Central Universities in China (Grant No.2023CDJXY-025)Chongqing Municipal Natural Science Foundation of China (Grant No.CSTB2023NSCQ-JQX0003)。
文摘The new energy vehicle plays a crucial role in green transportation,and the energy management strategy of hybrid power systems is essential for ensuring energy-efficient driving.This paper presents a state-of-the-art survey and review of reinforcement learning-based energy management strategies for hybrid power systems.Additionally,it envisions the outlook for autonomous intelligent hybrid electric vehicles,with reinforcement learning as the foundational technology.First of all,to provide a macro view of historical development,the brief history of deep learning,reinforcement learning,and deep reinforcement learning is presented in the form of a timeline.Then,the comprehensive survey and review are conducted by collecting papers from mainstream academic databases.Enumerating most of the contributions based on three main directions—algorithm innovation,powertrain innovation,and environment innovation—provides an objective review of the research status.Finally,to advance the application of reinforcement learning in autonomous intelligent hybrid electric vehicles,future research plans positioned as“Alpha HEV”are envisioned,integrating Autopilot and energy-saving control.
文摘The plug-in hybrid vehicles(PHEV)technology can effectively address the issues of poor dynamics and higher energy consumption commonly found in traditional mining dump trucks.Meanwhile,plug-in hybrid electric trucks can achieve excellent fuel economy through efficient energy management strategies(EMS).Therefore,a series hybrid system is constructed based on a 100-ton mining dump truck in this paper.And inspired by the dynamic programming(DP)algorithm,a predictive equivalent consumption minimization strategy(P-ECMS)based on the DP optimization result is proposed.Based on the optimal control manifold and the SOC reference trajectory obtained by the DP algorithm,the P-ECMS strategy performs real-time stage parameter optimization to obtain the optimal equivalent factor(EF).Finally,applying the equivalent consumption minimization strategy(ECMS)realizes real-time control.The simulation results show that the equivalent fuel consumption of the P-ECMS strategy under the experimentally collected mining cycle conditions is 150.8 L/100 km,which is 10.9%less than that of the common CDCS strategy(169.3 L/100 km),and achieves 99.47%of the fuel saving effect of the DP strategy(150 L/100 km).
文摘China's energy demand and energy imports have increased substantially in recent 5 years and will continue to grow in future. Increasing dependency on the world market and the tension between energy supply and demand clearly show that energy is becoming a major constraint for China's future economic development. We introduce the background of China's energy demand and supply in this paper and discuss China's energy strategy in the twentyfirst century, focusing on growth, energy security and environmental sustainability.
文摘“Those who owns the Middle East oil,will have the world.”The world’s major energy consumers-the United States and Russia holding the“energy card”meet in the Middle East.There are consensus and also contradictions in their energy strategies and interests.Based on the comparison between the energy strategy and policy of the two countries,this article aims to provide their experience in the Middle East for China to think and learn.
文摘In face of challenges to its energy security,China has been making adjustments in its energy policy and energy development strategy since mid-1990s,and implementing a strategy for overseas energy development.Compared with Central Asia,Latin America,Southeast Asia and West Africa,the Middle East is still the major source for China’s overseas energy cooperation and development.To avoid over-dependence on the energy resources in the Middle East,China seeks more overseas energy sources and transportation channels other than those in or connected to the Middle East.However,the primary role of the Middle East in China’s overall strategy for overseas energy development is still irreplaceable by that of any other region,at least for the near future.This situation will surely produce an increasingly important impact on China’s Middle East policy,moving China to take a more active posture in the political and economic arena of the region.It can even be expected that China to maintain its stable and friendly relations with Middle East countries,will,more likely than ever,act as a diplomatic mediator in trying to resolve certain longstanding conflicts in the region.
基金This project is supported by Electric Vehicle Key Project of National 863 Program of China (No.2001AA501200, 2001AA501211).
文摘Energy management strategy (EMS) is the core of the real-time controlalgorithm of the hybrid electric vehicle (HEV). A novel EMS using the logic threshold approach withincorporation of a stand-by optimization algorithm is proposed. The aim of it is to minimize theengine fuel consumption and maintain the battery state of charge (SOC) in its operation range, whilesatisfying the vehicle performance and drivability requirements. The hybrid powertrain bench testis carried out to collect data of the engine, motor and battery pack, which are used in the EMS tocontrol the powertrain. Computer simulation model of the HEV is established in the MATLAB/Simulinkenvironment according to the bench test results. Simulation results are presented for behaviors ofthe engine, motor and battery. The proposed EMS is implemented for a real parallel hybrid carcontrol system and validated by vehicle field tests.
基金Shanghai Municipal Science and Technology Commission, China (No. 033012017).
文摘A novel parallel hybrid electrical urban bus (PHEUB) configuration consisting of an extra one-way clutch and an automatic mechanical transmission (AMT) is taken as the study subject. An energy management strategy combining a logic threshold approach and an instantaneous optimization algorithm is proposed for the investigated PHEUB. The objective of the energy management strategy is to achieve acceptable vehicle performance and drivability requirements while simultaneously maximizing the engine fuel consumption and maintaining the battery state of charge in its operation range at all times. Under the environment of Matlab/Simulink, a computer simulation model for the PHEUB is constructed by using the model building method combining theoretical analysis and bench test data. Simulation and experiment results for China Typical Bus Driving Schedule at Urban District (CTBDS_UD) are obtained, and the results indicate that the proposed control strategy not only controls the hybrid system efficiently but also improves the fuel economy significantly.
文摘In this paper, a plug-in hybrid electrical vehicle(PHEV) is taken as the research object, and its dynamic performance and economic performance are taken as the research goals. Battery charge-sustaining(CS) period is divided into power mode and economy mode. Energy management strategy designing methods of power mode and economy mode are proposed. Maximum velocity, acceleration performance and fuel consumption are simulated during the CS period in the AVL CRUISE simulation environment. The simulation results indicate that the maximum velocity and acceleration time of the power mode are better than those in the economy mode. Fuel consumption of the economy mode is better than that in the power mode. Fuel consumption of PHEV during the CS period is further improved by using the methods proposed in this paper, and this is meaningful for research and development of PHEV.
基金Sponsored by the National Natural Science Foundation of China(Grant No.50375033)the National Key Laboratory of Vehicular Transmission(Grant No.51457050105HT0112)
文摘Aimed at the relatively lower energy density and complicated coordinating operation between two power sources,a special energy control strategy is required to maximize the fuel saving potential.Then a new type of configuration for hydrostatic transmission hybrid vehicles(PHHV) and the selection criterion for important components are proposed.Based on the optimization of planet gear transmission ratio and the analysis of optimal energy distribution for the proposed PHHV on a representative urban driving cycle,a fuzzy torque control strategy and a braking energy regeneration strategy are designed and developed to realize the real-time control of energy for the proposed PHHV.Simulation results demonstrate that the energy control strategy effectively improves the fuel economy of PHHV.
基金This work was supported by National Natural Science Foundation of China under Project 51325701,51377030,and 51407042.
文摘The flux-modulated compound-structure permanent magnet synchronous machine (CS-PMSM), composed of a brushless double rotor machine (DRM) and a conventional permanent magnet synchronous machine (PMSM), is a power split device for plug-in hybrid electric vehicles. In this paper, its operating principle and mathematical model are introduced. A modified current controller with decoupled state feedback is proposed and verified. The system control strategy is simulated in Matlab, and the feasibility of the control system is proven. To improve fuel economy, an energy management strategy based on fuzzy logic controller is proposed and evaluated by the Urban Dynamometer Driving Schedule (UDDS) drive cycle. The results show that the total energy consumption is similar to that of Prius 2012.
基金supported by the National Natural Science Foundation(Nos.51977181,52077180,52007157)Fok Ying-Tong Education Foundation of China(No.171104).
文摘This paper proposes an energy management strategy for a fuel cell(FC)hybrid power system based on dynamic programming and state machine strategy,which takes into account the durability of the FC and the hydrogen consumption of the system.The strategy first uses the principle of dynamic programming to solve the optimal power distribution between the FC and supercapacitor(SC),and then uses the optimization results of dynamic programming to update the threshold values in each state of the finite state machine to realize real-time management of the output power of the FC and SC.An FC/SC hybrid tramway simulation platform is established based on RTLAB real-time simulator.The compared results verify that the proposed EMS can improve the durability of the FC,increase its working time in the high-efficiency range,effectively reduce the hydrogen consumption,and keep the state of charge in an ideal range.
基金a phased achievement of Gansu Province’s Major Science and Technology Project(W22KJ2722005)“Research on Optimal Configuration and Operation Strategy of Energy Storage under“New Energy+Energy Storage”Mode”.
文摘Capacity allocation and energy management strategies for energy storage are critical to the safety and economical operation of microgrids.In this paper,an improved energymanagement strategy based on real-time electricity price combined with state of charge is proposed to optimize the economic operation of wind and solar microgrids,and the optimal allocation of energy storage capacity is carried out by using this strategy.Firstly,the structure and model of microgrid are analyzed,and the outputmodel of wind power,photovoltaic and energy storage is established.Then,considering the interactive power cost between the microgrid and the main grid and the charge-discharge penalty cost of energy storage,an optimization objective function is established,and an improved energy management strategy is proposed on this basis.Finally,a physicalmodel is built inMATLAB/Simulink for simulation verification,and the energy management strategy is compared and analyzed on sunny and rainy days.The initial configuration cost function of energy storage is added to optimize the allocation of energy storage capacity.The simulation results show that the improved energy management strategy can make the battery charge-discharge response to real-time electricity price and state of charge better than the traditional strategy on sunny or rainy days,reduce the interactive power cost between the microgrid system and the power grid.After analyzing the change of energy storage power with cost,we obtain the best energy storage capacity and energy storage power.
文摘In 1949, the Chinese energy industry had an annual output of 20 million tons of standard coal equivalent, which was relatively small. The energy industry has developed at a rapid rate since the 1950s. Some statistics show that the annual production of coal in 1990 increased 34 times and the annual production of electricity in 1990 increased 140 times compared to 1949. The annual output of energy reached one billion standard coal equivalent in 1990 and 1.24 billion in 1995. Although China has become a big country for energy production, the energy supply does not yet meet the needs of its economic development. This situation first
文摘I. Preface
Biomass includes the residues of agriculture, forest and stock breeding, as well as straw, algae and energy crops. In its broad meaning, biomass is a kind of organic matter produced by the photosynthesis of plants, which is not only renewable, but also contains plentiful energy.
基金supported by the National Key Research and Development Program of China(No.2020YFB1600400)the Scientific Research Project of the Department of Transport of Shaanxi Province(No.18-27R).
文摘This paper uses the minimization and weighted sum of battery capacity loss and energy consumption under driving cycles as objective functions to improve the economy of Electric Vehicles(EVs)with an hybrid energy storage system composed of power batteries and ultracapacitors.Furthermore,Dynamic Programming(DP)is employed to determine the objective function values under different weight coefficients,the comprehensive cost consisting of battery aging and power consumption costs,and the relationship between the hybrid power distribution.We also evaluate the real-time fuzzy Energy Management Strategy(EMS),fuzzy control strategies,and a strategy based on DP using the World Light vehicle Test Procedure(WLTP)driving cycle and a synthesis driving cycle derived from New European Driving Cycle(NEDC),WLTP,and Urban Dynamometer Driving Schedule(UDDS)as examples.Then,the proposed strategy is compared with the fuzzy control strategy and the strategy based on DP.Compared with fuzzy energy management strategy(namely FZY-EMS),the proposed EMS reduces the battery capacity loss and system energy consumption.The results demonstrate the effectiveness of the proposed EMS in improving EV economy.
文摘With the heavy dependence of world's growing economy on energy supply, the energy issue again comes into the spotlight throughout the world. How to ensure energy security is a great concern to most countries in the world. In this paper, trends in energy supply, energy security mechanism and new challenges are analyzed. As well as, China's security strategies are also proposed.