Common clay, Kaolin and Bentonite were used as additives to prepare water-transmitting coating fiber, respectively, and the water-transmitting characteristic of coating fiber was studied. Different water-transmitting ...Common clay, Kaolin and Bentonite were used as additives to prepare water-transmitting coating fiber, respectively, and the water-transmitting characteristic of coating fiber was studied. Different water-transmitting coating fibers were prepared by coating fiber using coating material with different mass proportions of additives to adhesive. And the coating materials were made from three kinds of inorganic clays as additives respectively and polyvinyl alcohol (PVA) as adhesive. Furthermore, the surface morphology and water-transmitting capacity of coating fiber were studied by SEM, Perkin Elmer Diamond SII thermal multi-analyzer and instrument for quick measurement moisture M30. The experimental results indicate that water-transmitting coating fibers made from three kinds of clays all have water-transmitting capacity. The surface of water-transmitting coating fiber prepared by common clay T is continuous and compact, and the water-transmitting effect is better than coating fibers made from other clays.展开更多
可再生能源渗透率的提高对电力系统稳定运行造成冲击,导致电网调频过程的复杂化。为此提出一种基于多目标优化的风储协同一次调频控制策略。首先,构建风储协同参与的一次调频模型,以变桨控制使风机参与电网调频,并对风速分解以消除其不...可再生能源渗透率的提高对电力系统稳定运行造成冲击,导致电网调频过程的复杂化。为此提出一种基于多目标优化的风储协同一次调频控制策略。首先,构建风储协同参与的一次调频模型,以变桨控制使风机参与电网调频,并对风速分解以消除其不确定性的影响,同时针对储能荷电状态(state of charge, SOC)特性,对储能采用基于SOC变化的自适应控制,待优化可变系统参数表征风储出力需求;然后,对风储协同参与调频的主要代价进行分析,根据调频效果、风电与储能调频损耗进行多目标优化问题设计;在此基础上,通过适应度系数的时变调整对NSGA-Ⅱ遗传算法进行改进,获取最优状态下的参数解集,并设计综合评价指标对Pareto前端分布进行最优解选择。仿真结果表明,不同Pareto前端位置的解能够更好地反映不同控制目标的考量,获取满足不同场景下调频需求的最优系统参数。展开更多
为充分发挥储能参与一次调频的优势,在虚拟惯性控制及下垂控制的基础上,通过分析储能参与电网一次调频的动态特性,提出一种跟随荷电状态(state of charge,SOC)变化和最大频率偏差动态调整出力的自适应综合控制策略。该策略在负荷扰动初...为充分发挥储能参与一次调频的优势,在虚拟惯性控制及下垂控制的基础上,通过分析储能参与电网一次调频的动态特性,提出一种跟随荷电状态(state of charge,SOC)变化和最大频率偏差动态调整出力的自适应综合控制策略。该策略在负荷扰动初期采用正虚拟惯性控制模拟发电机惯性响应;在频率恢复期提出可变系数的负虚拟惯性控制,综合考虑频率恶化程度(最大频差)和SOC动态调整负虚拟惯性控制出力以加快频率恢复;在整个调频期内采用基于双曲正切函数特性的变系数下垂控制,下垂系数的大小与SOC有关,可在保证调频需求的同时兼顾电池容量的保持效果。最终形成以正/负虚拟惯性控制改善储能调频动态特性为主、下垂控制改善储能稳态特性为主,3种方法互相配合的综合控制策略,并提出电池储能参与一次调频的评价指标。最后在Matlab\Simulink中搭建了区域调频模型,分别对阶跃负荷扰动和连续负荷扰动进行仿真,验证了策略的有效性。展开更多
基金Funded by the National High Technology Research and Development Program of China (2001AA322100)the Ministry of Education of Republic of China (106086)the Cooperation and Merger Found of Beijing ( ZH114140537)
文摘Common clay, Kaolin and Bentonite were used as additives to prepare water-transmitting coating fiber, respectively, and the water-transmitting characteristic of coating fiber was studied. Different water-transmitting coating fibers were prepared by coating fiber using coating material with different mass proportions of additives to adhesive. And the coating materials were made from three kinds of inorganic clays as additives respectively and polyvinyl alcohol (PVA) as adhesive. Furthermore, the surface morphology and water-transmitting capacity of coating fiber were studied by SEM, Perkin Elmer Diamond SII thermal multi-analyzer and instrument for quick measurement moisture M30. The experimental results indicate that water-transmitting coating fibers made from three kinds of clays all have water-transmitting capacity. The surface of water-transmitting coating fiber prepared by common clay T is continuous and compact, and the water-transmitting effect is better than coating fibers made from other clays.
文摘可再生能源渗透率的提高对电力系统稳定运行造成冲击,导致电网调频过程的复杂化。为此提出一种基于多目标优化的风储协同一次调频控制策略。首先,构建风储协同参与的一次调频模型,以变桨控制使风机参与电网调频,并对风速分解以消除其不确定性的影响,同时针对储能荷电状态(state of charge, SOC)特性,对储能采用基于SOC变化的自适应控制,待优化可变系统参数表征风储出力需求;然后,对风储协同参与调频的主要代价进行分析,根据调频效果、风电与储能调频损耗进行多目标优化问题设计;在此基础上,通过适应度系数的时变调整对NSGA-Ⅱ遗传算法进行改进,获取最优状态下的参数解集,并设计综合评价指标对Pareto前端分布进行最优解选择。仿真结果表明,不同Pareto前端位置的解能够更好地反映不同控制目标的考量,获取满足不同场景下调频需求的最优系统参数。
文摘为充分发挥储能参与一次调频的优势,在虚拟惯性控制及下垂控制的基础上,通过分析储能参与电网一次调频的动态特性,提出一种跟随荷电状态(state of charge,SOC)变化和最大频率偏差动态调整出力的自适应综合控制策略。该策略在负荷扰动初期采用正虚拟惯性控制模拟发电机惯性响应;在频率恢复期提出可变系数的负虚拟惯性控制,综合考虑频率恶化程度(最大频差)和SOC动态调整负虚拟惯性控制出力以加快频率恢复;在整个调频期内采用基于双曲正切函数特性的变系数下垂控制,下垂系数的大小与SOC有关,可在保证调频需求的同时兼顾电池容量的保持效果。最终形成以正/负虚拟惯性控制改善储能调频动态特性为主、下垂控制改善储能稳态特性为主,3种方法互相配合的综合控制策略,并提出电池储能参与一次调频的评价指标。最后在Matlab\Simulink中搭建了区域调频模型,分别对阶跃负荷扰动和连续负荷扰动进行仿真,验证了策略的有效性。