This paper introduces a dynamic network model together with a phasor measurement unit(PMU)measurement model suitable for power system state estimation under spoofing attacks on the global positioning system(GPS)receiv...This paper introduces a dynamic network model together with a phasor measurement unit(PMU)measurement model suitable for power system state estimation under spoofing attacks on the global positioning system(GPS)receivers of PMUs.The spoofing attacks may introduce time-varying phase offsets in the affected PMU measurements.An algorithm is developed to jointly estimate the state of the network,which amounts to the nodal voltages in rectangular coordinates,as well as the time-varying attacks.The algorithm features closedform updates.The effectiveness of the algorithm is verified on the standard IEEE transmission networks.It is numerically shown that the estimation performance is improved when the dynamic network model is accounted for compared with a previously reported static approach.展开更多
An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform...An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform of the IPS is designed,which consists of the light-emitting diode( LED)based transmitter,the receiver and the positioning server. To reduce the impact caused by measurement errors,both inertial sensing data and the received signal strength( RSS) from the VLC are calibrated. Then,a practical propagation model is established to obtain the distance between the transmitter and the receiver from the RSS measurements. Furthermore,a hybrid positioning algorithm is proposed by using the adaptive Kalman filter( AKF) and the weighted least squares( WLS)trilateration to estimate the positions of the mobile targets.Experimental results show that the developed IPS using the proposed hybrid positioning algorithm can extend the localization area of VLC,mitigate the IMU drifts and improve the positioning accuracy of mobile targets.展开更多
An indoor positioning method for robots is presented to improve the precision of displacement measurement using only low-cost inertial measurement units(IMUs).Firstly,a high-fidelity displacement estimation for linear...An indoor positioning method for robots is presented to improve the precision of displacement measurement using only low-cost inertial measurement units(IMUs).Firstly,a high-fidelity displacement estimation for linear motion is proposed.A new robot motion model is designed as well as an axis alignment that only uses a single axis of the accelerometer.The integral error of velocity is eliminated by a new subsection calculation method.Two complementary IMUs are combined by assigning them different weights to obtain high accuracy displacement results.Secondly,an orientation estimation based on a fusion filter for the steering motion is proposed.Experiments show that the proposed method significantly improves the accuracy of linear motion measurement and is effective for the indoor positioning of a robot.展开更多
The paper provides a short history of the phasor measurement unit(PMU) concept. The origin of PMU is traced to the work on developing computer based distance relay using symmetrical component theory. PMUs evolved from...The paper provides a short history of the phasor measurement unit(PMU) concept. The origin of PMU is traced to the work on developing computer based distance relay using symmetrical component theory. PMUs evolved from a portion of this relay architecture. The need for synchronization using global positioning system(GPS) is discussed, and the wide area measurement system(WAMS) utilizing PMU signals is described. A number of applications of this technology are discussed, and an account of WAMS activities in many countries around the world are provided.展开更多
基金supported by the U.S.National Science Foundation(No.ECCS-1719043)
文摘This paper introduces a dynamic network model together with a phasor measurement unit(PMU)measurement model suitable for power system state estimation under spoofing attacks on the global positioning system(GPS)receivers of PMUs.The spoofing attacks may introduce time-varying phase offsets in the affected PMU measurements.An algorithm is developed to jointly estimate the state of the network,which amounts to the nodal voltages in rectangular coordinates,as well as the time-varying attacks.The algorithm features closedform updates.The effectiveness of the algorithm is verified on the standard IEEE transmission networks.It is numerically shown that the estimation performance is improved when the dynamic network model is accounted for compared with a previously reported static approach.
基金The National Natural Science Foundation of China(No.61741102,61471164,61601122)the Fundamental Research Funds for the Central Universities(No.SJLX_160040)
文摘An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform of the IPS is designed,which consists of the light-emitting diode( LED)based transmitter,the receiver and the positioning server. To reduce the impact caused by measurement errors,both inertial sensing data and the received signal strength( RSS) from the VLC are calibrated. Then,a practical propagation model is established to obtain the distance between the transmitter and the receiver from the RSS measurements. Furthermore,a hybrid positioning algorithm is proposed by using the adaptive Kalman filter( AKF) and the weighted least squares( WLS)trilateration to estimate the positions of the mobile targets.Experimental results show that the developed IPS using the proposed hybrid positioning algorithm can extend the localization area of VLC,mitigate the IMU drifts and improve the positioning accuracy of mobile targets.
基金National Natural Science Foundation of China(61375103,61533004,61320106012,and 61321002)the 863 Program of China(2014AA041602,2015AA042305 and 2015AA043202)+2 种基金the Key Technologies Research and Development Program(2015BAF13B01 and 2015BAK35B01)the Beijing Municipal Science and Technology Project(D161100003016002)the "111" Project under Grant B08043
文摘An indoor positioning method for robots is presented to improve the precision of displacement measurement using only low-cost inertial measurement units(IMUs).Firstly,a high-fidelity displacement estimation for linear motion is proposed.A new robot motion model is designed as well as an axis alignment that only uses a single axis of the accelerometer.The integral error of velocity is eliminated by a new subsection calculation method.Two complementary IMUs are combined by assigning them different weights to obtain high accuracy displacement results.Secondly,an orientation estimation based on a fusion filter for the steering motion is proposed.Experiments show that the proposed method significantly improves the accuracy of linear motion measurement and is effective for the indoor positioning of a robot.
文摘The paper provides a short history of the phasor measurement unit(PMU) concept. The origin of PMU is traced to the work on developing computer based distance relay using symmetrical component theory. PMUs evolved from a portion of this relay architecture. The need for synchronization using global positioning system(GPS) is discussed, and the wide area measurement system(WAMS) utilizing PMU signals is described. A number of applications of this technology are discussed, and an account of WAMS activities in many countries around the world are provided.