We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state...We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state of the cavity. In particular, we have managed to avoid the conventional dispersive coupling so that high speed gate operation is achieved which is very important in view of decoherence. We show that this multipartite pair-wise controlled phase operation makes the generation of two-dimensional cluster states very efficient.展开更多
针对直流微电网中储能系统功率波动、负载侧负荷频繁投切等不确定因素引起母线电压产生波动的问题,以储能系统中三相交错并联双向DC-DC变换器为研究对象,提出一种基于级联有限时间扩张状态观测器(cascade finite-time extended state ob...针对直流微电网中储能系统功率波动、负载侧负荷频繁投切等不确定因素引起母线电压产生波动的问题,以储能系统中三相交错并联双向DC-DC变换器为研究对象,提出一种基于级联有限时间扩张状态观测器(cascade finite-time extended state observer,CFT-ESO)的微分平坦和改进型超螺旋滑模双闭环复合控制策略.首先,建立三相交错并联双向DC-DC变换器的数学模型,并根据微分平坦理论将其直流系统转化为微分平坦系统,结合两级具有快速收敛性的有限时间扩张状态观测器提高对系统集总扰动的估计精度.其次,采用内环微分平坦控制、外环改进型超螺旋滑模控制的双闭环控制系统,既能提高系统动态响应过程,又能利用高阶滑模控制算法抑制抖振,同时解决变换器升压模式中非最小相位问题.再次,通过Lyapunov理论证明控制系统的稳定性.最后,利用MATLAB/Simulink仿真软件以及搭建实验平台对控制策略进行验证,结果表明,本文所提控制策略能够很好地抵抗扰动,提高系统的暂态性能.展开更多
State-space equations were applied to formulate the queuing and delay of traffic at a single intersection in this paper. The signal control of a single intersection was then modeled as a discrete-time optimal control ...State-space equations were applied to formulate the queuing and delay of traffic at a single intersection in this paper. The signal control of a single intersection was then modeled as a discrete-time optimal control problem, with consideration of the constraints of stream conflicts, saturation flow rate, minimum green time, and maximum green time. The problem cannot be solved directly due to the nonlinear constraints. However, the results of qualitative analysis were used to develop a first-phase signal control algorithm. Simulation results show that the algorithm substantially reduces the total delay compared to fixed-time control.展开更多
针对电池组并联均衡研究较少及能量利用率较低的问题,该文提出了一种基于部分功率变换(partial power conversion,PPC)的电池组并联均衡拓扑。该拓扑结合双有源桥(dual active bridge,DAB)变换器和串联谐振型双有源桥(series resonant d...针对电池组并联均衡研究较少及能量利用率较低的问题,该文提出了一种基于部分功率变换(partial power conversion,PPC)的电池组并联均衡拓扑。该拓扑结合双有源桥(dual active bridge,DAB)变换器和串联谐振型双有源桥(series resonant dual active bridge, SR-DAB)变换器,采用PPC结构,能够极大减少系统损耗,提升系统效率。在此基础上,以电池荷电状态(state of charge, SOC)均衡为目标,在SR-DAB的单移相控制中加入SOC均衡控制,实现电池组的充放电均衡。基于RT-Box的实时仿真结果表明,所提拓扑及均衡控制策略能够有效地实现并联电池组之间的均衡,且在不同工况下其系统效率均高于采用全功率处理(full power processing,FPP)结构系统的效率。展开更多
基金Project supported by the National Fundamental Research Program of China (Grant No. 2013CB921804)the National Natural Science Foundation of China(Grant No. 11004065)+1 种基金the Natural Science Foundation of Guangdong Province of China (Grant Nos. 10451063101006312 and S2011040000403)the Funds of the Education Department of Anhui Province of China (Grant Nos. KJ2010A323, 2010SQRL187, and KJ2012B075)
文摘We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state of the cavity. In particular, we have managed to avoid the conventional dispersive coupling so that high speed gate operation is achieved which is very important in view of decoherence. We show that this multipartite pair-wise controlled phase operation makes the generation of two-dimensional cluster states very efficient.
文摘针对直流微电网中储能系统功率波动、负载侧负荷频繁投切等不确定因素引起母线电压产生波动的问题,以储能系统中三相交错并联双向DC-DC变换器为研究对象,提出一种基于级联有限时间扩张状态观测器(cascade finite-time extended state observer,CFT-ESO)的微分平坦和改进型超螺旋滑模双闭环复合控制策略.首先,建立三相交错并联双向DC-DC变换器的数学模型,并根据微分平坦理论将其直流系统转化为微分平坦系统,结合两级具有快速收敛性的有限时间扩张状态观测器提高对系统集总扰动的估计精度.其次,采用内环微分平坦控制、外环改进型超螺旋滑模控制的双闭环控制系统,既能提高系统动态响应过程,又能利用高阶滑模控制算法抑制抖振,同时解决变换器升压模式中非最小相位问题.再次,通过Lyapunov理论证明控制系统的稳定性.最后,利用MATLAB/Simulink仿真软件以及搭建实验平台对控制策略进行验证,结果表明,本文所提控制策略能够很好地抵抗扰动,提高系统的暂态性能.
基金Supported by the National Natural Science Foundation of China (No. 60572005)
文摘State-space equations were applied to formulate the queuing and delay of traffic at a single intersection in this paper. The signal control of a single intersection was then modeled as a discrete-time optimal control problem, with consideration of the constraints of stream conflicts, saturation flow rate, minimum green time, and maximum green time. The problem cannot be solved directly due to the nonlinear constraints. However, the results of qualitative analysis were used to develop a first-phase signal control algorithm. Simulation results show that the algorithm substantially reduces the total delay compared to fixed-time control.
文摘针对电池组并联均衡研究较少及能量利用率较低的问题,该文提出了一种基于部分功率变换(partial power conversion,PPC)的电池组并联均衡拓扑。该拓扑结合双有源桥(dual active bridge,DAB)变换器和串联谐振型双有源桥(series resonant dual active bridge, SR-DAB)变换器,采用PPC结构,能够极大减少系统损耗,提升系统效率。在此基础上,以电池荷电状态(state of charge, SOC)均衡为目标,在SR-DAB的单移相控制中加入SOC均衡控制,实现电池组的充放电均衡。基于RT-Box的实时仿真结果表明,所提拓扑及均衡控制策略能够有效地实现并联电池组之间的均衡,且在不同工况下其系统效率均高于采用全功率处理(full power processing,FPP)结构系统的效率。
