为解决电网峰谷差持续扩大带来的影响,从用户侧角度出发,针对空调房间、电热水器和电动汽车分别提出了柔性负荷优化控制算法。该算法基于分时电价,同时考虑用户经济效益和舒适度进行双目标优化控制,并通过智能用户终端实现。在算法中,...为解决电网峰谷差持续扩大带来的影响,从用户侧角度出发,针对空调房间、电热水器和电动汽车分别提出了柔性负荷优化控制算法。该算法基于分时电价,同时考虑用户经济效益和舒适度进行双目标优化控制,并通过智能用户终端实现。在算法中,改进了传统的空调房间和热水器负荷模型,将复杂的多变量强耦合过程解耦为多个独立的单变量子过程,并采用参数回归获取模型参数,减少算法中的随机变量。其次,将电动汽车纳入优化控制,分别研究了单向充电电动汽车(grid to vehicle,G2V)和双向供电电动汽车(vehicle to grid,V2G)的优化算法。采用粒子群算法分别求解优化结果。基于MATLAB的仿真结果验证了所提算法在经济利益、用户体验和电网削峰填谷方面上的优势。展开更多
变电站设备种类繁多、缺陷类型复杂、特征差异大,传统的基于深度学习的缺陷图像检测模型难以同时有效处理不同设备的多种缺陷。为此,提出了一种基于语义信息距离解耦的缺陷图像检测模型(sematic-distance based decoupling detection mo...变电站设备种类繁多、缺陷类型复杂、特征差异大,传统的基于深度学习的缺陷图像检测模型难以同时有效处理不同设备的多种缺陷。为此,提出了一种基于语义信息距离解耦的缺陷图像检测模型(sematic-distance based decoupling detection model,SDB-DDM)。首先对缺陷类别进行语义信息聚簇,构建解耦式网络结构,然后对网络输出进行加权锚框融合,并在损失函数中加入局部预测损失以提升预测能力,同时提出解耦式非极大值抑制策略以加快模型推理速度。该模型可根据缺陷类别进行自适应调整,以适用变电运维多类别缺陷图像检测的应用场景。实验结果显示,该模型的平均精度均值达到了69.68%。同平台下相较于目前性能最佳的目标检测模型(YOLOX),精度提升了1.36个百分点,参数量下降了5%,推理速度提升了34%。展开更多
基于稠密气体分子动力学和气固两相流体动力学，建立流化床稠密气固两相离散颗粒运动-碰撞解耦模型，采用直接模拟蒙特卡罗方法（DSMC）模拟颗粒间的碰撞，采用考虑颗粒脉动流动对气相湍流流动影响的大涡模拟（LES）研究气相湍流，单颗...基于稠密气体分子动力学和气固两相流体动力学，建立流化床稠密气固两相离散颗粒运动-碰撞解耦模型，采用直接模拟蒙特卡罗方法（DSMC）模拟颗粒间的碰撞，采用考虑颗粒脉动流动对气相湍流流动影响的大涡模拟（LES）研究气相湍流，单颗粒运动满足牛顿第二定律，颗粒相和气相相间作用的双向耦合由牛顿第三定律确定。数值模拟流化床中颗粒流动以及气泡的生成、长大和破碎过程，获得颗粒轴向和径向速度的概率密度分布，及颗粒浓度分布。计算结果表明床内气泡的形成造成床内颗粒的循环，使得流化床内颗粒具有不同的轴向和径向脉动速度，颗粒分速度分布近似服从高斯分布。颗粒温度随颗粒浓度增加，达到最大值后，随颗粒浓度增大而下降。流化床颗粒浓度脉动主要是低频部分，高频分量较低，表明在流化床内颗粒浓度脉动频率低，能量高，颗粒浓度脉动主频率为0．04～1．0Hz，其值与Pain et al．获得的颗粒浓度脉动主频率基本吻合。展开更多
Fluvial processes comprise water flow,sediment transport and bed evolution,which normally feature distinct time scales.The time scales of sediment transport and bed deformation relative to the flow essentially measure...Fluvial processes comprise water flow,sediment transport and bed evolution,which normally feature distinct time scales.The time scales of sediment transport and bed deformation relative to the flow essentially measure how fast sediment transport adapts to capacity region in line with local flow scenario and the bed deforms in comparison with the flow,which literally dictates if a capacity based and/or decoupled model is justified.This paper synthesizes the recently developed multiscale theory for sediment-laden flows over erodible bed,with bed load and suspended load transport,respectively.It is unravelled that bed load transport can adapt to capacity sufficiently rapidly even under highly unsteady flows and thus a capacity model is mostly applicable,whereas a non-capacity model is critical for suspended sediment because of the lower rate of adaptation to capacity.Physically coupled modelling is critical for fluvial processes characterized by rapid bed variation.Applications are outlined on very active bed load sediment transported by flash floods and landslide dam break floods.展开更多
文摘为解决电网峰谷差持续扩大带来的影响,从用户侧角度出发,针对空调房间、电热水器和电动汽车分别提出了柔性负荷优化控制算法。该算法基于分时电价,同时考虑用户经济效益和舒适度进行双目标优化控制,并通过智能用户终端实现。在算法中,改进了传统的空调房间和热水器负荷模型,将复杂的多变量强耦合过程解耦为多个独立的单变量子过程,并采用参数回归获取模型参数,减少算法中的随机变量。其次,将电动汽车纳入优化控制,分别研究了单向充电电动汽车(grid to vehicle,G2V)和双向供电电动汽车(vehicle to grid,V2G)的优化算法。采用粒子群算法分别求解优化结果。基于MATLAB的仿真结果验证了所提算法在经济利益、用户体验和电网削峰填谷方面上的优势。
文摘变电站设备种类繁多、缺陷类型复杂、特征差异大,传统的基于深度学习的缺陷图像检测模型难以同时有效处理不同设备的多种缺陷。为此,提出了一种基于语义信息距离解耦的缺陷图像检测模型(sematic-distance based decoupling detection model,SDB-DDM)。首先对缺陷类别进行语义信息聚簇,构建解耦式网络结构,然后对网络输出进行加权锚框融合,并在损失函数中加入局部预测损失以提升预测能力,同时提出解耦式非极大值抑制策略以加快模型推理速度。该模型可根据缺陷类别进行自适应调整,以适用变电运维多类别缺陷图像检测的应用场景。实验结果显示,该模型的平均精度均值达到了69.68%。同平台下相较于目前性能最佳的目标检测模型(YOLOX),精度提升了1.36个百分点,参数量下降了5%,推理速度提升了34%。
文摘基于稠密气体分子动力学和气固两相流体动力学，建立流化床稠密气固两相离散颗粒运动-碰撞解耦模型，采用直接模拟蒙特卡罗方法（DSMC）模拟颗粒间的碰撞，采用考虑颗粒脉动流动对气相湍流流动影响的大涡模拟（LES）研究气相湍流，单颗粒运动满足牛顿第二定律，颗粒相和气相相间作用的双向耦合由牛顿第三定律确定。数值模拟流化床中颗粒流动以及气泡的生成、长大和破碎过程，获得颗粒轴向和径向速度的概率密度分布，及颗粒浓度分布。计算结果表明床内气泡的形成造成床内颗粒的循环，使得流化床内颗粒具有不同的轴向和径向脉动速度，颗粒分速度分布近似服从高斯分布。颗粒温度随颗粒浓度增加，达到最大值后，随颗粒浓度增大而下降。流化床颗粒浓度脉动主要是低频部分，高频分量较低，表明在流化床内颗粒浓度脉动频率低，能量高，颗粒浓度脉动主频率为0．04～1．0Hz，其值与Pain et al．获得的颗粒浓度脉动主频率基本吻合。
基金supported by the National Natural Science Foundation of China (10932012 and 10972164)State Key Basic Research and Development Program (973) of China (2007CB714106)
文摘Fluvial processes comprise water flow,sediment transport and bed evolution,which normally feature distinct time scales.The time scales of sediment transport and bed deformation relative to the flow essentially measure how fast sediment transport adapts to capacity region in line with local flow scenario and the bed deforms in comparison with the flow,which literally dictates if a capacity based and/or decoupled model is justified.This paper synthesizes the recently developed multiscale theory for sediment-laden flows over erodible bed,with bed load and suspended load transport,respectively.It is unravelled that bed load transport can adapt to capacity sufficiently rapidly even under highly unsteady flows and thus a capacity model is mostly applicable,whereas a non-capacity model is critical for suspended sediment because of the lower rate of adaptation to capacity.Physically coupled modelling is critical for fluvial processes characterized by rapid bed variation.Applications are outlined on very active bed load sediment transported by flash floods and landslide dam break floods.
