The landscape environment of urban blocks plays a significant role in improving the comfort of urban thermal environment and promoting green and high-quality development.The 342 papers related to the research on the i...The landscape environment of urban blocks plays a significant role in improving the comfort of urban thermal environment and promoting green and high-quality development.The 342 papers related to the research on the impact of urban block landscape environment on thermal comfort in China,collected by CNKI(China National Knowledge Infrastructure)from 2002 to 2022,are used as the research object.Through bibliometric statistical analysis,LLR algorithm,and cluster analysis,the current research status of the impact of urban block landscape environment on thermal comfort in China is analyzed and processed,and its external characteristics are identified.Using the information visualization software CiteSpace,the research topics in the field of the impact of urban block landscape environment on thermal comfort are presented in the form of knowledge graphs.Through co-occurrence analysis of keywords and trend of word frequency changes,the development trends of research hotspots and cutting-edge fields of the impact of urban block landscape environment on thermal comfort are determined,hoping to provide reference for future research in this field.展开更多
智能软开关(Soft Open Points,SOP)的普及使得多台区联合运行成为趋势。针对大规模户用光伏接入低压配电网带来的电压越限、网损和三相不平衡问题,提出一种基于SOP的柔性互联两阶段优化控制架构。日前阶段,考虑长时间尺度光伏及负荷功率...智能软开关(Soft Open Points,SOP)的普及使得多台区联合运行成为趋势。针对大规模户用光伏接入低压配电网带来的电压越限、网损和三相不平衡问题,提出一种基于SOP的柔性互联两阶段优化控制架构。日前阶段,考虑长时间尺度光伏及负荷功率,建立以台区Ⅰ、Ⅱ总网损最小、三相不平衡度最小为目标函数的三相四线柔性互联低压配电网优化模型,求取SOP三相功率出力,采用模型凸化的方式降低求解难度。日内阶段,针对光伏及负荷5分钟短时功率扰动带来的电压波动越限问题,基于日前SOP优化结果,利用SOP两侧换流器电压-无功下垂控制方法抑制电压越限问题。仿真结果表明,所提两阶段优化控制策略能够有效抑制高比例光伏并网带来的供电质量问题。此外,为了保障优化结果对比分析的客观性,选取与本文优化参数相近、光伏接入情况与网络模型相同的文献案例进行对比分析。分析结果表明,通过功率在空间上的转移,实现不同交流台区间的功率互济,解决了多个台区存在的电压质量和网损问题,并且控制变量数目更少,综合优化结果更好。展开更多
基金the National Natural Science Foundation of China(51708004)Beijing Youth Teaching Master Team Construction Project(108051360023XN261)Yuyou Talent Training Program of North China University of Technology(215051360020XN160/009).
文摘The landscape environment of urban blocks plays a significant role in improving the comfort of urban thermal environment and promoting green and high-quality development.The 342 papers related to the research on the impact of urban block landscape environment on thermal comfort in China,collected by CNKI(China National Knowledge Infrastructure)from 2002 to 2022,are used as the research object.Through bibliometric statistical analysis,LLR algorithm,and cluster analysis,the current research status of the impact of urban block landscape environment on thermal comfort in China is analyzed and processed,and its external characteristics are identified.Using the information visualization software CiteSpace,the research topics in the field of the impact of urban block landscape environment on thermal comfort are presented in the form of knowledge graphs.Through co-occurrence analysis of keywords and trend of word frequency changes,the development trends of research hotspots and cutting-edge fields of the impact of urban block landscape environment on thermal comfort are determined,hoping to provide reference for future research in this field.
文摘智能软开关(Soft Open Points,SOP)的普及使得多台区联合运行成为趋势。针对大规模户用光伏接入低压配电网带来的电压越限、网损和三相不平衡问题,提出一种基于SOP的柔性互联两阶段优化控制架构。日前阶段,考虑长时间尺度光伏及负荷功率,建立以台区Ⅰ、Ⅱ总网损最小、三相不平衡度最小为目标函数的三相四线柔性互联低压配电网优化模型,求取SOP三相功率出力,采用模型凸化的方式降低求解难度。日内阶段,针对光伏及负荷5分钟短时功率扰动带来的电压波动越限问题,基于日前SOP优化结果,利用SOP两侧换流器电压-无功下垂控制方法抑制电压越限问题。仿真结果表明,所提两阶段优化控制策略能够有效抑制高比例光伏并网带来的供电质量问题。此外,为了保障优化结果对比分析的客观性,选取与本文优化参数相近、光伏接入情况与网络模型相同的文献案例进行对比分析。分析结果表明,通过功率在空间上的转移,实现不同交流台区间的功率互济,解决了多个台区存在的电压质量和网损问题,并且控制变量数目更少,综合优化结果更好。
