A Fiber Bragg Grating-Based Dynamic Tension Detection System for Overhead Transmission Line Galloping.

Galloping of overhead transmission lines (OHTLs) may induce conductor breakage and tower collapse, and there is no effective method for long distance distribution on-line galloping monitoring. To overcome the drawbacks of the conventional galloping monitoring systems, such as sensitivity to electromagnetic interference, the need for onsite power, and short lifetimes, a novel optical remote passive measuring system is proposed in the paper. Firstly, to solve the hysteresis and eccentric load problem in tension sensing, and to extent the dynamic response range, an 'S' type elastic element structure with flanges was proposed. Then, a tension experiment was carried out to demonstrate the dynamic response characteristics. Moreover, the designed tension sensor was stretched continuously for 30 min to observe its long time stability. Last but not the least, the sensor was mounted on a 70 m conductor model, and the conductor was oscillated at different frequencies to investigate the dynamic performance of the sensor. The experimental results demonstrate the sensor is suitable for the OHTL galloping detection. Compared with the conventional sensors for OHTL monitoring, the system has many advantages, such as easy installation, no flashover risk, distribution monitoring, better bandwidth, improved accuracy and higher reliability.

Secure and Time-Aware Communication of Wireless Sensors Monitoring Overhead Transmission Lines.

Existing transmission power grids suffer from high maintenance costs and scalability issues along with a lack of effective and secure system monitoring. To address these problems, we propose to use Wireless Sensor Networks (WSNs) as a technology to achieve energy efficient, reliable, and low-cost remote monitoring of transmission grids. With WSNs, smart grid enables both utilities and customers to monitor, predict and manage energy usage effectively and react to possible power grid disturbances in a timely manner. However, the increased application of WSNs also introduces new security challenges, especially related to privacy, connectivity, and security management, repeatedly causing unpredicted expenditures. Monitoring the status of the power system, a large amount of sensors generates massive amount of sensitive data. In order to build an effective Wireless Sensor Network (WSN) for a smart grid, we focus on designing a methodology of efficient and secure delivery of the data measured on transmission lines. We perform a set of simulations, in which we examine different routing algorithms, security mechanisms and WSN deployments in order to select the parameters that will not affect the delivery time but fulfill their role and ensure security at the same time. Furthermore, we analyze the optimal placement of direct wireless links, aiming at minimizing time delays, balancing network performance and decreasing deployment costs.

Development of automatic arc sag measurement equipment for tensioned line tightening construction on overhead transmission lines.

Due to the low degree of automation of the existing arc droop measurement device, the tension line digital twin system is not yet able to simulate the change of arc droop in the actual engineering situation in a high degree of real time. To this end, a kind of arc droop automatic measuring equipment applicable to the working condition of tension frame line tightening construction is developed. In terms of hardware, firstly, the STC microcontroller is used to control the motor to achieve free movement of the equipment on the wire. Secondly, the Beidou positioning module is used to collect the spatial coordinates of each point on the wire, thereby obtaining the spatial attitude of the wire and calculating the final sag. Finally, LoRa technology with long transmission distance and low power consumption is selected for wireless transmission of controlled data and collected data. The software system of the device is equipped with the motor's action logic, which cooperates with the hardware to respond to the control commands issued by the terminal. The developed arc droop measurement equipment has been successfully applied in the project, compared with the traditional arc droop observation construction method construction efficiency increased by 28%, the difference between the observation file arc droop and the design arc droop after erection of the line is 1.96%. Digital simulation and remote guidance of arc sag variations by the digital twin system for tension racking lines was realized while ensuring the engineering requirements.