As the power system transitions to a new green and low-carbon paradigm,the penetration of renewable energy in China’s power system is gradually increasing.However,the variability and uncertainty of renewable energy o...As the power system transitions to a new green and low-carbon paradigm,the penetration of renewable energy in China’s power system is gradually increasing.However,the variability and uncertainty of renewable energy output limit its profitability in the electricity market and hinder its market-based integration.This paper first constructs a wind-solar-thermalmulti-energy complementary system,analyzes its external game relationships,and develops a bi-level market optimization model.Then,it considers the contribution levels of internal participants to establish a comprehensive internal distribution evaluation index system.Finally,simulation studies using the IEEE 30-bus system demonstrate that the multi-energy complementary system stabilizes nodal outputs,enhances the profitability of market participants,and promotes the market-based integration of renewable energy.展开更多
Using the concept of the base forces, a new finite element method （base force element method, BFEM） based on the complementary energy principle is presented for accurate modeling of structures with large displacemen...Using the concept of the base forces, a new finite element method （base force element method, BFEM） based on the complementary energy principle is presented for accurate modeling of structures with large displacements and large rotations. First, the complementary energy of an element is described by taking the base forces as state variables, and is then separated into deformation and rotation parts for the case of large deformation. Second, the control equations of the BFEM based on the complementary energy principle are derived using the Lagrange multiplier method. Nonlinear procedure of the BFEM is then developed. Finally, several examples are analyzed to illustrate the reliability and accuracy of the BFEM.展开更多
Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple compleme...Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple complementary energy resources,a comprehensive assessment of the energy efficiency is of paramount importance.First,a multi-dimensional evaluation system with four primary indexes of energy utilization,environmental protection,system operation,and economic efficiency and 21 secondary indexes is constructed to comprehensively portray the UES.Considering that the evaluation system may contain a large number of indexes and that there is overlapping information among them,an energy efficiency evaluation method based on data processing,dimensionality reduction,integration of combined weights,and gray correlation analysis is proposed.This method can effectively reduce the number of calculations and improve the accuracy of energy efficiency assessments.Third,a demonstration project for a UES in China is presented.The energy efficiency of each scenario is assessed using six operational scenarios.The results show that Scenario 5,in which parks operate independently and investors build shared energy-storage equipment,has the best results and is best suited for green and low-carbon development.The results of the comparative assessment methods show that the proposed method provides a good energy efficiency assessment.This study provides a reference for the optimal planning,construction,and operation of UESs with multiple energy sources.展开更多
The multi-energy complementary distributed energy system (MCDES) covers a variety of energy forms, involves complex operation modes, and contains a wealth of control equipment and coupling links. It can realize the co...The multi-energy complementary distributed energy system (MCDES) covers a variety of energy forms, involves complex operation modes, and contains a wealth of control equipment and coupling links. It can realize the complementary and efficient use of different types of energy, which is the basic component of the physical layer of the Energy Internet. In this paper, aiming at the demand of the energy application for towns, a distributed energy system based on multi-energy complementary is constructed. Firstly, the supply condition of the distributed energy for the demonstration project is analyzed, and the architecture of the multi-energy complementary distributed energy system is established. Then the regulation strategy of the multi-energy complementary distributed energy system is proposed. Finally, an overall system scheme for the multi-energy complementary distributed energy system suitable for towns is developed, which provides a solid foundation for the development and promotion of the multi-energy complementary distributed energy system.展开更多
【目的】“双碳”背景下,节能降碳已成为保障国家能源安全与实现绿色转型的关键。油田联合站作为油气集输与处理的能耗“大户”,传统的“电网+燃气锅炉”供能模式成本高、排放大、韧性差等矛盾突出,亟需构建适应高比例可再生能源、季节...【目的】“双碳”背景下,节能降碳已成为保障国家能源安全与实现绿色转型的关键。油田联合站作为油气集输与处理的能耗“大户”,传统的“电网+燃气锅炉”供能模式成本高、排放大、韧性差等矛盾突出,亟需构建适应高比例可再生能源、季节调控能力强大的多能互补系统。【方法】针对油田联合站高耗能、高排放、高韧性风险的“三高”问题,提出了“风光-氢-储-荷”多能系统协同架构:将风光发电替代网购电,以电解制氢-储氢-燃料电池形成电-氢-电闭环,并利用热电联产机组、热泵、储热多源供热;创新性地将阶梯碳交易与价格/激励双重需求响应纳入统一优化模型,从经济、低碳、韧性多重目标对新建系统进行评价分析。【结果】基于混合整数线性规划(Mixed-integer Linear Programming,MILP)问题,设置了4种场景,以大庆油田某联合站为例分析表明:①与传统供能模式相比,含氢循环的多能互补系统能源利用效率提高了30%以上,年运行成本降低41.20%,碳排放强度下降2.10%,且可再生能源消纳率提升至90%以上;②阶梯碳交易通过递增碳价杠杆,使系统碳交易成本上升24.98%、碳排放量下降6.74%;③叠加需求响应后,可进一步降低碳排放1.30%、碳交易成本下降1.51%,实现减排与降本“双赢”;④氢能子系统作为跨时空调节器,在风光发电时段存储富余绿电,在负荷高峰或极端天气下则反向供电、供热,全年弃风弃光率控制在1%以内,显著增强供能韧性。经济性测算显示,在现行碳价与电解槽投资水平下,新建系统增量投资回收期为5~8年,若碳价低于80元/t、电解槽成本下降至2500元/kW以内,回收期可缩短至4年。【结论】研究成果已形成可复制的油田联合站供能低碳改造技术路线,有助于伴生气资源丰富、电热负荷稳定的老联合站提质增效,也可为高比例可再生能源新区块微网规划提供“电-热-氢”协同范式。展开更多
基金funded by the National Key R&D Program of China,grant number 2019YFB1505400.
文摘As the power system transitions to a new green and low-carbon paradigm,the penetration of renewable energy in China’s power system is gradually increasing.However,the variability and uncertainty of renewable energy output limit its profitability in the electricity market and hinder its market-based integration.This paper first constructs a wind-solar-thermalmulti-energy complementary system,analyzes its external game relationships,and develops a bi-level market optimization model.Then,it considers the contribution levels of internal participants to establish a comprehensive internal distribution evaluation index system.Finally,simulation studies using the IEEE 30-bus system demonstrate that the multi-energy complementary system stabilizes nodal outputs,enhances the profitability of market participants,and promotes the market-based integration of renewable energy.
基金supported by the China Postdoctoral Science Foundation Funded Project (20080430038) the Funding Project for Academic Human Resources Development in Institutions of Higher Learning Under the Jurisdiction of Beijing Municipality (05004999200602)
文摘Using the concept of the base forces, a new finite element method （base force element method, BFEM） based on the complementary energy principle is presented for accurate modeling of structures with large displacements and large rotations. First, the complementary energy of an element is described by taking the base forces as state variables, and is then separated into deformation and rotation parts for the case of large deformation. Second, the control equations of the BFEM based on the complementary energy principle are derived using the Lagrange multiplier method. Nonlinear procedure of the BFEM is then developed. Finally, several examples are analyzed to illustrate the reliability and accuracy of the BFEM.
基金supported by the National Natural Science Foundation of China under Grant 51567002 and Grant 50767001.
文摘Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple complementary energy resources,a comprehensive assessment of the energy efficiency is of paramount importance.First,a multi-dimensional evaluation system with four primary indexes of energy utilization,environmental protection,system operation,and economic efficiency and 21 secondary indexes is constructed to comprehensively portray the UES.Considering that the evaluation system may contain a large number of indexes and that there is overlapping information among them,an energy efficiency evaluation method based on data processing,dimensionality reduction,integration of combined weights,and gray correlation analysis is proposed.This method can effectively reduce the number of calculations and improve the accuracy of energy efficiency assessments.Third,a demonstration project for a UES in China is presented.The energy efficiency of each scenario is assessed using six operational scenarios.The results show that Scenario 5,in which parks operate independently and investors build shared energy-storage equipment,has the best results and is best suited for green and low-carbon development.The results of the comparative assessment methods show that the proposed method provides a good energy efficiency assessment.This study provides a reference for the optimal planning,construction,and operation of UESs with multiple energy sources.
文摘The multi-energy complementary distributed energy system (MCDES) covers a variety of energy forms, involves complex operation modes, and contains a wealth of control equipment and coupling links. It can realize the complementary and efficient use of different types of energy, which is the basic component of the physical layer of the Energy Internet. In this paper, aiming at the demand of the energy application for towns, a distributed energy system based on multi-energy complementary is constructed. Firstly, the supply condition of the distributed energy for the demonstration project is analyzed, and the architecture of the multi-energy complementary distributed energy system is established. Then the regulation strategy of the multi-energy complementary distributed energy system is proposed. Finally, an overall system scheme for the multi-energy complementary distributed energy system suitable for towns is developed, which provides a solid foundation for the development and promotion of the multi-energy complementary distributed energy system.
文摘【目的】“双碳”背景下,节能降碳已成为保障国家能源安全与实现绿色转型的关键。油田联合站作为油气集输与处理的能耗“大户”,传统的“电网+燃气锅炉”供能模式成本高、排放大、韧性差等矛盾突出,亟需构建适应高比例可再生能源、季节调控能力强大的多能互补系统。【方法】针对油田联合站高耗能、高排放、高韧性风险的“三高”问题,提出了“风光-氢-储-荷”多能系统协同架构:将风光发电替代网购电,以电解制氢-储氢-燃料电池形成电-氢-电闭环,并利用热电联产机组、热泵、储热多源供热;创新性地将阶梯碳交易与价格/激励双重需求响应纳入统一优化模型,从经济、低碳、韧性多重目标对新建系统进行评价分析。【结果】基于混合整数线性规划(Mixed-integer Linear Programming,MILP)问题,设置了4种场景,以大庆油田某联合站为例分析表明:①与传统供能模式相比,含氢循环的多能互补系统能源利用效率提高了30%以上,年运行成本降低41.20%,碳排放强度下降2.10%,且可再生能源消纳率提升至90%以上;②阶梯碳交易通过递增碳价杠杆,使系统碳交易成本上升24.98%、碳排放量下降6.74%;③叠加需求响应后,可进一步降低碳排放1.30%、碳交易成本下降1.51%,实现减排与降本“双赢”;④氢能子系统作为跨时空调节器,在风光发电时段存储富余绿电,在负荷高峰或极端天气下则反向供电、供热,全年弃风弃光率控制在1%以内,显著增强供能韧性。经济性测算显示,在现行碳价与电解槽投资水平下,新建系统增量投资回收期为5~8年,若碳价低于80元/t、电解槽成本下降至2500元/kW以内,回收期可缩短至4年。【结论】研究成果已形成可复制的油田联合站供能低碳改造技术路线,有助于伴生气资源丰富、电热负荷稳定的老联合站提质增效,也可为高比例可再生能源新区块微网规划提供“电-热-氢”协同范式。
