The paper introduces one design idea that making use of SCM to control Real-timely the dynamic compensation of reactive power.Firstly,design one Circuit to Sample the voltage and current,and by these datas we can easi...The paper introduces one design idea that making use of SCM to control Real-timely the dynamic compensation of reactive power.Firstly,design one Circuit to Sample the voltage and current,and by these datas we can easily calculate the power factor,and Voltage controller in the microcontroller to determine whether input the compensation capacitance according to the size of power factor,the paper also analyzes the principle of capacitance compensation and calculation method. Dynamic compensation for the entire process is quick and accurate.展开更多
The new Austrian tunneling method (NATM) is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs) associated with the...The new Austrian tunneling method (NATM) is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs) associated with their influences on geoengineering are complicated or unfortunately are overlooked, we should pay more attentions to internal features of rocks grades IV and V (even in local but mostly controlling zones). With increasing attentions to the characteristics, mechanism and influences of engineering construction-triggered geohazards, it is crucial to fully understand the disturbance of these geohazards on project construction. A reasonable determination method in construction procedure, i.e. the shape of working face, the type of engineering support and the choice of feasible procedure, should be considered in order to mitigate the construction-triggered geohazards. Due to their high sensitivity to groundwater and in-situ stress, various UGBs exhibit hysteretic nature and failure modes. To give a complete understanding on the internal causes, the emphasis on advanced comprehensive geological forecasting and overall reinforcement treatment is therefore of more practical significance. Compre- hensive evaluation of influential factors, identification of UGB, and measures of discontinuity dynamic controlling comprises the geoengineering condition evaluation and dynamic controlling method. In a case of a cut slope, the variations of UGBs and the impacts of key environmental factors are presented, where more severe construction-triggered geohazards emerged in construction stage than those predicted in design and field investigation stages. As a result, the weight ratios of different influential factors with respect to field investigation, design and construction are obtained.展开更多
为研究多重调谐质量阻尼器(Multiple Tuned Mass Damper,MTMD)抑制桥梁单阶涡振的性能,建立桥梁结构-MTMD系统竖弯涡振广义单自由度动力方程,以某大跨度悬索桥为背景进行MTMD减振控制效果和参数优化分析。采用数值方法求解动力方程,获...为研究多重调谐质量阻尼器(Multiple Tuned Mass Damper,MTMD)抑制桥梁单阶涡振的性能,建立桥梁结构-MTMD系统竖弯涡振广义单自由度动力方程,以某大跨度悬索桥为背景进行MTMD减振控制效果和参数优化分析。采用数值方法求解动力方程,获得系统在简谐涡激力下达到稳态谐振时结构的动力放大系数和MTMD对结构的附加模态阻尼比,并与单一频率调谐质量阻尼器(Single Tuned Mass Damper,STMD)的减振控制效果进行对比,然后以附加模态阻尼比为目标对MTMD进行参数优化。结果表明:MTMD比最优参数STMD拥有更宽的控制频带和更好的减振效果,经优化后的MTMD减振性能优于最优参数STMD。实际应用MTMD时,应选择较大广义质量、5~7种频率规格,并根据二者找到无量纲频率范围和各TMD阻尼比的惟一最优取值。展开更多
在“碳达峰•碳中和”国家能源战略变革背景下,大规模可再生能源的加速并网加剧了电力系统对于快速调频资源需求的迫切性,如何充分发挥以电池储能系统(battery energy storage systems,BESS)为代表的新型快速资源在电网调频中的作用是解...在“碳达峰•碳中和”国家能源战略变革背景下,大规模可再生能源的加速并网加剧了电力系统对于快速调频资源需求的迫切性,如何充分发挥以电池储能系统(battery energy storage systems,BESS)为代表的新型快速资源在电网调频中的作用是解决该问题的关键。首先,为满足电网各类型调频资源在自动发电控制(automatic generation control,AGC)系统中的接入监视与分类决策需求,提出“域-群-机”三级控制模型架构;然后,从BESS的荷电状态(state of charge,SOC)主动管理出发,提出基于改进的动态调频容量(dynamic available AGC,DAA)的多元集群协同控制策略,以及引入SOC影响因子的多点BESS功率分配策略;最后,结合实际电网的持续扰动工况及模拟跳机扰动工况进行仿真分析,验证了文中所提控制策略的有效性。文中所提策略不但可以显著改善各单点BESS的SOC一致性,而且能够提升电网调频品质。展开更多
We study projective synchronization with different scaling factors (PSDF) in N coupled chaotic systems networks. By using the adaptive linear control, some sufficient criteria for the PSDF in symmetrical and asymmet...We study projective synchronization with different scaling factors (PSDF) in N coupled chaotic systems networks. By using the adaptive linear control, some sufficient criteria for the PSDF in symmetrical and asymmetrical coupled networks are separately given based on the Lyapunov function method and the left eigenvalue theory. Numerical simulations for a generalized chaotic unified system are illustrated to verify the theoretical results.展开更多
文摘The paper introduces one design idea that making use of SCM to control Real-timely the dynamic compensation of reactive power.Firstly,design one Circuit to Sample the voltage and current,and by these datas we can easily calculate the power factor,and Voltage controller in the microcontroller to determine whether input the compensation capacitance according to the size of power factor,the paper also analyzes the principle of capacitance compensation and calculation method. Dynamic compensation for the entire process is quick and accurate.
基金support by the National Natural Science Foundation of China (No. 41372324)support from the Chinese Special Funds for Major State Basic Research Project under Grant No. 2010CB732001
文摘The new Austrian tunneling method (NATM) is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs) associated with their influences on geoengineering are complicated or unfortunately are overlooked, we should pay more attentions to internal features of rocks grades IV and V (even in local but mostly controlling zones). With increasing attentions to the characteristics, mechanism and influences of engineering construction-triggered geohazards, it is crucial to fully understand the disturbance of these geohazards on project construction. A reasonable determination method in construction procedure, i.e. the shape of working face, the type of engineering support and the choice of feasible procedure, should be considered in order to mitigate the construction-triggered geohazards. Due to their high sensitivity to groundwater and in-situ stress, various UGBs exhibit hysteretic nature and failure modes. To give a complete understanding on the internal causes, the emphasis on advanced comprehensive geological forecasting and overall reinforcement treatment is therefore of more practical significance. Compre- hensive evaluation of influential factors, identification of UGB, and measures of discontinuity dynamic controlling comprises the geoengineering condition evaluation and dynamic controlling method. In a case of a cut slope, the variations of UGBs and the impacts of key environmental factors are presented, where more severe construction-triggered geohazards emerged in construction stage than those predicted in design and field investigation stages. As a result, the weight ratios of different influential factors with respect to field investigation, design and construction are obtained.
基金supported by National Basic Research Program of China(2007CB407207)The National Key Technology R&D Program of China(2007BAC15B01)+1 种基金National Natural Science Foundation(Project No.40971236 and No.30901163)the Vilas Associate Award and the Hammel Faculty Fellow Award from the University of Wisconsin-Madison,and Innovation Grant from the State Key Laboratory of Resources and Environmental Information Systems
文摘为研究多重调谐质量阻尼器(Multiple Tuned Mass Damper,MTMD)抑制桥梁单阶涡振的性能,建立桥梁结构-MTMD系统竖弯涡振广义单自由度动力方程,以某大跨度悬索桥为背景进行MTMD减振控制效果和参数优化分析。采用数值方法求解动力方程,获得系统在简谐涡激力下达到稳态谐振时结构的动力放大系数和MTMD对结构的附加模态阻尼比,并与单一频率调谐质量阻尼器(Single Tuned Mass Damper,STMD)的减振控制效果进行对比,然后以附加模态阻尼比为目标对MTMD进行参数优化。结果表明:MTMD比最优参数STMD拥有更宽的控制频带和更好的减振效果,经优化后的MTMD减振性能优于最优参数STMD。实际应用MTMD时,应选择较大广义质量、5~7种频率规格,并根据二者找到无量纲频率范围和各TMD阻尼比的惟一最优取值。
文摘在“碳达峰•碳中和”国家能源战略变革背景下,大规模可再生能源的加速并网加剧了电力系统对于快速调频资源需求的迫切性,如何充分发挥以电池储能系统(battery energy storage systems,BESS)为代表的新型快速资源在电网调频中的作用是解决该问题的关键。首先,为满足电网各类型调频资源在自动发电控制(automatic generation control,AGC)系统中的接入监视与分类决策需求,提出“域-群-机”三级控制模型架构;然后,从BESS的荷电状态(state of charge,SOC)主动管理出发,提出基于改进的动态调频容量(dynamic available AGC,DAA)的多元集群协同控制策略,以及引入SOC影响因子的多点BESS功率分配策略;最后,结合实际电网的持续扰动工况及模拟跳机扰动工况进行仿真分析,验证了文中所提控制策略的有效性。文中所提策略不但可以显著改善各单点BESS的SOC一致性,而且能够提升电网调频品质。
基金Project supported by the National Natural Science Foundation of China (Grant No 60575038)
文摘We study projective synchronization with different scaling factors (PSDF) in N coupled chaotic systems networks. By using the adaptive linear control, some sufficient criteria for the PSDF in symmetrical and asymmetrical coupled networks are separately given based on the Lyapunov function method and the left eigenvalue theory. Numerical simulations for a generalized chaotic unified system are illustrated to verify the theoretical results.