Research On Online Monitoring Of Conductor Galloping Based On Beidou Differential Positioning

Galloping for transmission line refers to the transmission line conductor occurred eccentric over ice,and in the wind excitation generated a low frequency,large amplitude self-excited vibration.Not only that,it will cause line tripping,gold and insulator damage,broken wires,broken strands,tower damage,damage to the foundation,and even down the tower and other serious accidents.Therefore,galloping for transmission line is a serious disaster that endangers the safe and stable operation of transmission lines.Overhead transmission line is an important part of the national grid power system,and with the construction of china’s ultra-high voltage,the line is widely distributed and complex operation,operation and maintenance workload is increasing.Based on the above,online monitoring of transmission line galloping is very necessary.However,existing methods mainly use acceleration sensors and video monitoring,but the result of acceleration sensor measurement is a relative quantity and data dispersion will occur over time.The video monitoring is easily affected by weather and power supply,which can not achieve effective monitoring of galloping for transmission line.Therefore,this paper adopts the Beidou carrier phase differential positioning technology for online monitoring of wire galloping,which can visually obtain the observed value of galloping.The data are processed by improved kalman filtering algorithm to make the monitoring accuracy higher.The online monitoring device adopts the split design of acquisition unit and gateway,and adopts the periodic working mode and sleep mechanism to ensure the effective power supply and stable working of the monitoring device.Through experiments and field applications show that the device has the national grid online monitoring standards of transmission line galloping.The main contents of this thesis research are:(1)The study of the online monitoring method of transmission line galloping,a detailed introduction to the formation mechanism of wire dance and monitoring methods,and the application of Beidou differential positioning technology to monitor the transmission line galloping to improve the effectiveness of monitoring.The principles of pseudorange positioning and carrier phase differential technology are analyzed,and the commonly used methods of circumferential hop detection and whole circumferential ambiguity fixation are introduced.(2)The Beidou differential positioning accuracy is easily affected by noise and star selection,and the kalman filtering algorithm is used to model the transmission line galloping and dynamically filter the coordinates of the transmission line galloping trajectory.The state error equation and observation error equation of kalman equation are adjusted by satellite geometric accuracy factor(GDOP)and signal-to-noise ratio to make the obtained galloping characteristic quantity more accurate and reliable.(3)The online monitoring device of transmission line galloping based on Beidou differential positioning is developed.Considering the inconvenience of power supply on the wire and the high power requirement of the circuit system,the hardware adopts a split design and the working mode is cyclic.The monitoring device is divided into a wire-side acquisition unit and a tower-side gateway unit.The conductor end is responsible for collecting the galloping track and transmitting it to the gateway by lora,and the gateway is responsible for encrypting the transmission line status monitoring device according to "Information security access of transmission line monitoring device".This includes packaging and transmission to the intranet platform in accordance with the statute developed by the state electric "Q/gdw 242-2010 general technical specification for transmission line status monitoring device".