Power Inspection

With the development of the power industry, the importance of the safety and stability of transmission towers for power transportation is self-evident. Currently, most methods such as manual line inspection, helicopter line inspection, and aerial digital photography line inspection are used to ensure the safety of transmission lines. However, many transmission towers are located in mountainous areas, and these methods have unavoidable defects; Synthetic aperture radar has the advantages of high monitoring accuracy, wide monitoring range, and all-weather capability, which can meet the needs of monitoring settlement and deformation of power facilities, transmission channels, infrastructure, and environmental monitoring of transmission lines.

It is particularly suitable for the northern regions of China where traditional power inspection methods are subject to weather and terrain conditions due to the wide range and long duration of winter snowfall. In response to such situations, Suzhou Tianjing Yunhu Intelligent Technology Co., Ltd. used two main UAV platforms - the KWT X6L-15 multi rotor UAV equipped with Ku band SAR and the DJI M400 equipped with X-band SAR for flight experiments. They successfully carried out airborne MiniSAR power inspection operations in a snowy winter environment in a transmission line area in Hebei Province, completing high-precision scanning and sag hazard screening of transmission lines.

In practical applications, we can develop periodic monitoring plans based on specific needs and actual situations. For example, for important transmission towers or areas with complex terrain, monitoring frequency and accuracy can be strengthened; For general transmission towers or areas with relatively simple terrain, monitoring frequency and accuracy can be appropriately reduced. This can identify potential safety hazards and failure modes, and take corresponding measures in advance for manual intervention and handling.

Applying SAR technology to power inspection can achieve the following advantages:

1. Low cost, labor-saving, high efficiency

The limitations of traditional technology in different application scenarios of power line tower equipment are that conventional manual operations involve periodic data collection, high labor and equipment costs, and various errors and passive operations in manual measurement. Taking into account all factors, using polarimetric SAR radar data to monitor the vegetation, trees, transmission channels, and high-voltage transmission lines around the transmission channels can save manpower and material resources for transmission channel inspections under the guidance of the power grid management unit, improve management efficiency, achieve full coverage of regional monitoring, and effectively ensure the safe operation of transmission lines.

2. Large scale monitoring can be implemented

The traditional techniques for elevation measurement and 3D modeling of power line tower equipment structures are more expensive for modeling multiple substations over a large area. In comparison, SAR radar data assisted optical or infrared data can directly collect data from multiple power line tower equipment over a large area, with high efficiency and low cost.

3. No need to install sensor equipment on the ground

The traditional technology limitations in monitoring the settlement of various infrastructure such as transmission channels, substations, and high-voltage towers are the need to deploy a large number of sensors, and the communication and power supply of sensors require high manual maintenance costs. At the same time, sensors have the disadvantage of short service life and high maintenance costs in the later stage. Using SAR radar technology for monitoring, periodic large-scale monitoring can be completed without the need for surface sensor equipment.

X-band flight results	Ku band flight results

The above are the flight test results we obtained in a snowy environment in a transmission line area in Hebei Province. From the images, it can be seen that the quality of the flight data was excellent, verifying the reliability and practicality of this technology in extreme weather conditions. Both Ku band SAR and X-band SAR work stably in snowy weather and low temperature environments, and the clarity of the obtained radar images meets the expected standards.

The power inspection flight test in snowy environments in Hebei Province was successfully completed, and the test personnel obtained the power sag results through calculation and analysis, once again verifying the irreplaceable value of airborne SAR technology in extreme weather conditions. Based on high-resolution SAR images, it is possible to accurately identify changes in the shape of power lines (such as sag offset, broken strands), structural features of power towers (tower base settlement, tower body tilt), and intrusion of surrounding foreign objects (such as construction machinery and floating objects), providing high-precision all-weather monitoring data for the safe operation and maintenance of transmission lines.

The sag calculation is 20.60m with an accuracy of 3.2%

SAR can withstand any weather conditions, including heavy fog, rain, snow, or night, and its microwave signals can still penetrate through numerous obstructions, accurately capturing every hidden danger; — Transform invisible sag into visible data and invisible risks into quantifiable decision-making basis. Low cost, high efficiency, and no need to deploy sensors on the ground, airborne SAR is redefining the boundaries of power inspection with its unique technological advantages. In the future, our company will continue to deepen the cultivation of airborne SAR power inspection technology, which is expected to play a greater role in disaster inspection of power corridors, detection of ice and snow foreign objects, deformation of power facilities, and arc deformation of power lines!