随着可再生能源渗透率的提升,其不确定性给综合能源系统(integrated energy system,IES)的经济性和鲁棒性带来了极大挑战。为了促进可再生能源消纳以及降低碳排放量,提出了一种基于数据驱动的分布鲁棒优化(distributionally robust opti...随着可再生能源渗透率的提升,其不确定性给综合能源系统(integrated energy system,IES)的经济性和鲁棒性带来了极大挑战。为了促进可再生能源消纳以及降低碳排放量,提出了一种基于数据驱动的分布鲁棒优化(distributionally robust optimization,DRO)调度策略。首先,构建了由有机朗肯循环(organic Rankine cycle,ORC)、氢燃料电池和电动汽车等构成的供需灵活响应模型,并引入阶梯碳交易机制来约束系统碳排放量。其次,为了能获取最恶劣情况下的场景概率分布,采用综合范数对风电输出场景的概率分布置信集合进行约束。然后,以在最恶劣场景概率分布下综合能源系统运行总成本最低为目标建立两阶段鲁棒优化模型,并通过列和约束生成(column and constraint generation,CCG)算法对模型进行迭代求解。最后,算例仿真结果表明了所提模型和求解方法的有效性,并分析了阶梯碳交易机制和供需灵活响应模型对提高系统灵活性和低碳经济性的影响。展开更多
混合储能系统具有储能容量大、调节能力强等优点,有助于提高综合能源系统(integrated energy system,IES)的需求响应能力。首先,构建了一种电-氢-热混合储能系统(electric-hydrogen-thermal hybrid energy storage system,EHT-HESS),其...混合储能系统具有储能容量大、调节能力强等优点,有助于提高综合能源系统(integrated energy system,IES)的需求响应能力。首先,构建了一种电-氢-热混合储能系统(electric-hydrogen-thermal hybrid energy storage system,EHT-HESS),其中采用电解槽(electrolytic cell,EC)、蒸气重整反应(steam methane reforming,SMR)装置、储氢、热电联产氢燃料电池(hydrogen fuel cell,HFC)设备,实现电、气向氢能的转换,以及以氢能作为中间模态的“制氢-储氢-放氢/电/热”功能。其次,建立考虑EHT-HESS的IES需求响应策略优化模型,其中考虑IES响应电价和气价,同时根据富余风电量,进行购电、购气、用电、用热、用氢等策略决策的综合需求响应(integrated demand response,IDR)行为;并采用信息间隙决策理论(information gap decision theory,IGDT)计入概率分布未知的风电严重不确定性,采用基于综合范数的分布鲁棒优化(distributionally robust optimization,DRO)方法计入概率分布不完备的电价严重不确定性。最后,算例验证了模型和方法的合理性及有效性,并表明IES装设热电联产HFC构建EHT-HESS可实现氢能向电能与热能的转换,有助于增加风电消纳量,增加IDR决策的鲁棒性。展开更多
新能源出力的不确定性和电动汽车的无序充电给电力系统安全性带来极大挑战。首先建立确定性的风电场、光伏电站、储能设备、负荷需求响应及电动汽车充电站协调规划模型,以总成本最小化为目标。基于此,提出考虑新能源不确定性的电动汽车...新能源出力的不确定性和电动汽车的无序充电给电力系统安全性带来极大挑战。首先建立确定性的风电场、光伏电站、储能设备、负荷需求响应及电动汽车充电站协调规划模型,以总成本最小化为目标。基于此,提出考虑新能源不确定性的电动汽车充电站与储能协调优化两阶段分布鲁棒规划模型,第1阶段最小化基础场景的投建与运行成本,第2阶段则最小化考虑不确定场景的切负荷惩罚成本期望,通过列与约束生成CCG(col⁃umn and constraint generation)算法将该两阶段模型分解成主问题和子问题反复迭代求解。最后通过算例分析验证了所提模型的有效性与实用性。展开更多
Over the past few decades, urban freeway congestion has been highly recognized as a serious and worsening traffic problem in the world. To relieve freeway congestion, several active traffic and demand management (ATD...Over the past few decades, urban freeway congestion has been highly recognized as a serious and worsening traffic problem in the world. To relieve freeway congestion, several active traffic and demand management (ATDM) methods have been developed. Among them, variable speed limit (VSL) aims at regulating freeway mainline flow upstream to meet existing capacity and to harmonize vehicle speed. However, congestion may still be inevitable even with VSL implemented due to extremely high demand in actual practice. This study modified an existing VSL strategy by adding a new local constraint to suggest an achievable speed limit during the control period. As a queue is a product of the congestion phenomenon in freeway, the incentives of a queue build-up in the applied coordinated VSL control situation were analyzed. Considering a congestion occurrence (a queue build-up) characterized by a sudden and sharp speed drop, speed contours were utilized to demonstrate the congestion distribution over a whole freeway network in various sce- narios. Finally, congestion distributions found in both VSL control and non-VS control situations for various scenarios were investigated to explore the impact of the applied coordinated VSL control on the congestion distribution. An authentic stretch of V^hitemud Drive (I~~ID), an urban freeway corridor in Edmonton, Alberta, Canada, was employed to implement this modified coordinated VSL control strategy; and a calibrated micro-simu- lation VISSIM model (model functions) was applied as the substitute of the real-world traffic system to test the above mentioned performance. The exploration task in this study can lay the groundwork for future research on how to improve the presented VSL control strategy for achieving the congestion mitigation effect on freeway.展开更多
文摘随着可再生能源渗透率的提升,其不确定性给综合能源系统(integrated energy system,IES)的经济性和鲁棒性带来了极大挑战。为了促进可再生能源消纳以及降低碳排放量,提出了一种基于数据驱动的分布鲁棒优化(distributionally robust optimization,DRO)调度策略。首先,构建了由有机朗肯循环(organic Rankine cycle,ORC)、氢燃料电池和电动汽车等构成的供需灵活响应模型,并引入阶梯碳交易机制来约束系统碳排放量。其次,为了能获取最恶劣情况下的场景概率分布,采用综合范数对风电输出场景的概率分布置信集合进行约束。然后,以在最恶劣场景概率分布下综合能源系统运行总成本最低为目标建立两阶段鲁棒优化模型,并通过列和约束生成(column and constraint generation,CCG)算法对模型进行迭代求解。最后,算例仿真结果表明了所提模型和求解方法的有效性,并分析了阶梯碳交易机制和供需灵活响应模型对提高系统灵活性和低碳经济性的影响。
文摘新能源出力的不确定性和电动汽车的无序充电给电力系统安全性带来极大挑战。首先建立确定性的风电场、光伏电站、储能设备、负荷需求响应及电动汽车充电站协调规划模型,以总成本最小化为目标。基于此,提出考虑新能源不确定性的电动汽车充电站与储能协调优化两阶段分布鲁棒规划模型,第1阶段最小化基础场景的投建与运行成本,第2阶段则最小化考虑不确定场景的切负荷惩罚成本期望,通过列与约束生成CCG(col⁃umn and constraint generation)算法将该两阶段模型分解成主问题和子问题反复迭代求解。最后通过算例分析验证了所提模型的有效性与实用性。
基金supported by the Natural Sciences and Engineering Research Council(NSERC) of Canada, City of Edmonton,and Transport Canadasupported by the National Natural Science Foundation of China(No.51208052,51308058)the Science and Technology Research and Development Program of Shaanxi Province,China(No.2013K13-04-02)
文摘Over the past few decades, urban freeway congestion has been highly recognized as a serious and worsening traffic problem in the world. To relieve freeway congestion, several active traffic and demand management (ATDM) methods have been developed. Among them, variable speed limit (VSL) aims at regulating freeway mainline flow upstream to meet existing capacity and to harmonize vehicle speed. However, congestion may still be inevitable even with VSL implemented due to extremely high demand in actual practice. This study modified an existing VSL strategy by adding a new local constraint to suggest an achievable speed limit during the control period. As a queue is a product of the congestion phenomenon in freeway, the incentives of a queue build-up in the applied coordinated VSL control situation were analyzed. Considering a congestion occurrence (a queue build-up) characterized by a sudden and sharp speed drop, speed contours were utilized to demonstrate the congestion distribution over a whole freeway network in various sce- narios. Finally, congestion distributions found in both VSL control and non-VS control situations for various scenarios were investigated to explore the impact of the applied coordinated VSL control on the congestion distribution. An authentic stretch of V^hitemud Drive (I~~ID), an urban freeway corridor in Edmonton, Alberta, Canada, was employed to implement this modified coordinated VSL control strategy; and a calibrated micro-simu- lation VISSIM model (model functions) was applied as the substitute of the real-world traffic system to test the above mentioned performance. The exploration task in this study can lay the groundwork for future research on how to improve the presented VSL control strategy for achieving the congestion mitigation effect on freeway.