传统继电保护仅利用本单元的电气量及有限的状态量完成故障判断,不能反映电网的整体运行状况,相互之间缺乏协调配合,为此提出了站域保护的基本概念。研究了适用于智能变电站的站域保护逻辑结构,站域保护系统通过交换机和以太网实现了变...传统继电保护仅利用本单元的电气量及有限的状态量完成故障判断,不能反映电网的整体运行状况,相互之间缺乏协调配合,为此提出了站域保护的基本概念。研究了适用于智能变电站的站域保护逻辑结构,站域保护系统通过交换机和以太网实现了变电站内智能设备间信息的共享和互操作,系统釆用集中式的处理结构,利用多信息进行故障定位。结合典型的500 k V变电站接线,分析了按电压等级构建的站域保护配置方案。基于智能变电站信息共享的站域保护信息量完整,改善了传统继电保护的不足,能提升继电保护性能和系统安全稳定运行能力。展开更多
This paper presents a novel method to improve the performance of high-DOF image base visual servoing （IBVS） with an uncalibrated camera. Firstly, analysis and comparison between point-based and moment-based features...This paper presents a novel method to improve the performance of high-DOF image base visual servoing （IBVS） with an uncalibrated camera. Firstly, analysis and comparison between point-based and moment-based features are carried out with respect to a 4-DOF positioning task. Then, an extended interaction matrix （IM） related to the digital image, and a Kalman filter （KF）-based estimation algorithm of the extended IM without calibration and IM model are proposed. Finally, the KF-based algorithm is extended to realize an approximation to decoupled control scheme. Experimental results conducted on an industrial robot show that our proposed methods can provide accurate estimation of IM, and achieve similar performance compared with traditional calibration-based method. Therefore, the proposed methods can be applied to any robot control system in variational environments, and can realize instant operation to planar object with complex and unknown shape at large displacement.展开更多
An accelerated singular value thresholding (SVT) algorithm was introduced for matrix completion in a recent paper [1], which applies an adaptive line search scheme and improves the convergence rate from O(1/N) for SVT...An accelerated singular value thresholding (SVT) algorithm was introduced for matrix completion in a recent paper [1], which applies an adaptive line search scheme and improves the convergence rate from O(1/N) for SVT to O(1/N2), where N is the number of iterations. In this paper, we show that it is the same as the Nemirovski’s approach, and then modify it to obtain an accelerate Nemirovski’s technique and prove the convergence. Our preliminary computational results are very favorable.展开更多
文摘传统继电保护仅利用本单元的电气量及有限的状态量完成故障判断,不能反映电网的整体运行状况,相互之间缺乏协调配合,为此提出了站域保护的基本概念。研究了适用于智能变电站的站域保护逻辑结构,站域保护系统通过交换机和以太网实现了变电站内智能设备间信息的共享和互操作,系统釆用集中式的处理结构,利用多信息进行故障定位。结合典型的500 k V变电站接线,分析了按电压等级构建的站域保护配置方案。基于智能变电站信息共享的站域保护信息量完整,改善了传统继电保护的不足,能提升继电保护性能和系统安全稳定运行能力。
基金supported by the National Natural Science Foundation of China (No. 60675048)
文摘This paper presents a novel method to improve the performance of high-DOF image base visual servoing （IBVS） with an uncalibrated camera. Firstly, analysis and comparison between point-based and moment-based features are carried out with respect to a 4-DOF positioning task. Then, an extended interaction matrix （IM） related to the digital image, and a Kalman filter （KF）-based estimation algorithm of the extended IM without calibration and IM model are proposed. Finally, the KF-based algorithm is extended to realize an approximation to decoupled control scheme. Experimental results conducted on an industrial robot show that our proposed methods can provide accurate estimation of IM, and achieve similar performance compared with traditional calibration-based method. Therefore, the proposed methods can be applied to any robot control system in variational environments, and can realize instant operation to planar object with complex and unknown shape at large displacement.
文摘An accelerated singular value thresholding (SVT) algorithm was introduced for matrix completion in a recent paper [1], which applies an adaptive line search scheme and improves the convergence rate from O(1/N) for SVT to O(1/N2), where N is the number of iterations. In this paper, we show that it is the same as the Nemirovski’s approach, and then modify it to obtain an accelerate Nemirovski’s technique and prove the convergence. Our preliminary computational results are very favorable.
