由于电力系统的动态特性,由广域测量系统(wide area measurement system,WAMS)/数据采集与监视控制(supervisory control and data acquisition,SCADA)系统收集来的量测信息不可避免地存在粗量测误差、系统状态突变等各种异常情况。针...由于电力系统的动态特性,由广域测量系统(wide area measurement system,WAMS)/数据采集与监视控制(supervisory control and data acquisition,SCADA)系统收集来的量测信息不可避免地存在粗量测误差、系统状态突变等各种异常情况。针对这一问题,提出一种采用自适应动态状态估计器的并能有效检测、辨识和排除WAMS/SCADA系统中异常情况的信息校正算法。该算法依据动态状态估计器预测系统状态的能力,利用标准化新息以及加权新息与标准化新息的最大比值来检测和辨识多个坏数据、负荷突变、网络拓扑结构错误以及这3种异常同时发生的情况,并利用标准化新息和残差来验证异常处理的效果。数值结果表明所提算法能够快速、准确、有效地检测、辨识和排除动态状态估计过程中的各种异常情况。展开更多
Gas-path performance estimation plays an important role in aero-engine health management, and Kalman Filter(KF) is a well-known technique to estimate performance degradation. In previous studies, it is assumed that di...Gas-path performance estimation plays an important role in aero-engine health management, and Kalman Filter(KF) is a well-known technique to estimate performance degradation. In previous studies, it is assumed that different kinds of sensors are with the same sampling rate, and they are used for state estimation by the KF simultaneously. However, it is hard to achieve state estimation using various kinds of sensor measurements at the same sampling rate due to a complex network and physical characteristic differences between sensors, especially in an advanced multisensor architecture. For this purpose, a multi-rate sensor fusion using the information filtering approach is proposed based on the square-root cubature rule, which is called Multi-rate Squareroot Cubature Information Filter(MSCIF) to track engine performance degradation. Soft measurement synchronization of the MSCIF is designed to provide a sensor fusion condition for multiple sampling rates of measurement, and a fault sensor is isolated by maximum likelihood validation before state estimation. The contribution of this paper is to supply a novel multi-rate informationfilter approach for sensor fault tolerant health estimation of an aero-engine in a multi-sensor system. Tests are conducted for aero-engine performance degradation estimation with multiple sampling rates of sensor measurement on both digital simulation and semi-physical experiment.Experimental results illustrate the superiority of the proposed algorithm in terms of degradation estimation accuracy and robustness to sensor failure in a multi-sensor system.展开更多
With the integration of information technologies, power system operations are increasingly threatened by cyber-attacks. It has even been revealed that an attacker can inject false data into real-time measurements stea...With the integration of information technologies, power system operations are increasingly threatened by cyber-attacks. It has even been revealed that an attacker can inject false data into real-time measurements stealthily without knowing the full configuration(e.g., network topology) of a power system. In this paper, we present a comprehensive review on false data injection attacks which utilize barrier conditions, blind identification techniques and data driven approaches to overcome limitations of incomplete network information. We also point out future research topics for facilitating the detection and prevention of such false data attacks.展开更多
This article investigates the optimal observation configuration of unmanned aerial vehicles(UAVs) based on angle and range measurements, and generalizes predecessors' researches in two dimensions into three dimens...This article investigates the optimal observation configuration of unmanned aerial vehicles(UAVs) based on angle and range measurements, and generalizes predecessors' researches in two dimensions into three dimensions. The relative geometry of the UAVs-target will significantly affect the state estimation performance of the target, the cost function based on the Fisher information matrix(FIM) is used to derive the FIM determinant of UAVs' observation in three-dimensional space, and the optimal observation geometric configuration that maximizes the determinant of the FIM is obtained. It is shown that the optimal observation configuration of the UAVs-target is usually not unique, and the optimal observation configuration is proved for two UAVs and three UAVs in three-dimension. The long-range over-the-horizon target tracking is simulated and analyzed based on the analysis of optimal observation configuration for two UAVs. The simulation results show that the theoretical analysis and control algorithm can effectively improve the positioning accuracy of the target. It can provide a helpful reference for the design of over-the-horizon target localization based on UAVs.展开更多
文摘由于电力系统的动态特性,由广域测量系统(wide area measurement system,WAMS)/数据采集与监视控制(supervisory control and data acquisition,SCADA)系统收集来的量测信息不可避免地存在粗量测误差、系统状态突变等各种异常情况。针对这一问题,提出一种采用自适应动态状态估计器的并能有效检测、辨识和排除WAMS/SCADA系统中异常情况的信息校正算法。该算法依据动态状态估计器预测系统状态的能力,利用标准化新息以及加权新息与标准化新息的最大比值来检测和辨识多个坏数据、负荷突变、网络拓扑结构错误以及这3种异常同时发生的情况,并利用标准化新息和残差来验证异常处理的效果。数值结果表明所提算法能够快速、准确、有效地检测、辨识和排除动态状态估计过程中的各种异常情况。
基金the financial supports of the National Natural Science Foundation of China(No.61304113)the Fundamental Research Funds for the Central Universities,China(No.NS2018018)Qinglan Project of Jiangsu Province
文摘Gas-path performance estimation plays an important role in aero-engine health management, and Kalman Filter(KF) is a well-known technique to estimate performance degradation. In previous studies, it is assumed that different kinds of sensors are with the same sampling rate, and they are used for state estimation by the KF simultaneously. However, it is hard to achieve state estimation using various kinds of sensor measurements at the same sampling rate due to a complex network and physical characteristic differences between sensors, especially in an advanced multisensor architecture. For this purpose, a multi-rate sensor fusion using the information filtering approach is proposed based on the square-root cubature rule, which is called Multi-rate Squareroot Cubature Information Filter(MSCIF) to track engine performance degradation. Soft measurement synchronization of the MSCIF is designed to provide a sensor fusion condition for multiple sampling rates of measurement, and a fault sensor is isolated by maximum likelihood validation before state estimation. The contribution of this paper is to supply a novel multi-rate informationfilter approach for sensor fault tolerant health estimation of an aero-engine in a multi-sensor system. Tests are conducted for aero-engine performance degradation estimation with multiple sampling rates of sensor measurement on both digital simulation and semi-physical experiment.Experimental results illustrate the superiority of the proposed algorithm in terms of degradation estimation accuracy and robustness to sensor failure in a multi-sensor system.
基金supported by National Natural Science Foundation of China (No. 51777062)National key research and development program (No. 2018YFB0904200) the Fundamental Research Funds for the Central UniversitiesHunan science and technology project (No. 2017XK2014)
文摘With the integration of information technologies, power system operations are increasingly threatened by cyber-attacks. It has even been revealed that an attacker can inject false data into real-time measurements stealthily without knowing the full configuration(e.g., network topology) of a power system. In this paper, we present a comprehensive review on false data injection attacks which utilize barrier conditions, blind identification techniques and data driven approaches to overcome limitations of incomplete network information. We also point out future research topics for facilitating the detection and prevention of such false data attacks.
基金supported by the National Natural Science Foundation of China(61703419)。
文摘This article investigates the optimal observation configuration of unmanned aerial vehicles(UAVs) based on angle and range measurements, and generalizes predecessors' researches in two dimensions into three dimensions. The relative geometry of the UAVs-target will significantly affect the state estimation performance of the target, the cost function based on the Fisher information matrix(FIM) is used to derive the FIM determinant of UAVs' observation in three-dimensional space, and the optimal observation geometric configuration that maximizes the determinant of the FIM is obtained. It is shown that the optimal observation configuration of the UAVs-target is usually not unique, and the optimal observation configuration is proved for two UAVs and three UAVs in three-dimension. The long-range over-the-horizon target tracking is simulated and analyzed based on the analysis of optimal observation configuration for two UAVs. The simulation results show that the theoretical analysis and control algorithm can effectively improve the positioning accuracy of the target. It can provide a helpful reference for the design of over-the-horizon target localization based on UAVs.
