Recently, at a substation of State Grid Quzhou Power Supply Company in Hangbu town, Quzhou, Zhejiang province, a lightweight indoor drone weighing only 1.1 kilograms was used to conduct autonomous inspections. The drone can perform precise inspections on various electrical equipment flexibly and efficiently.

Using an intelligent inspection system, staff members issue work plans and monitor real-time drone footage through the system. At the operational area, the drone slowly takes off from the nest device upon receiving the signal for the inspection task and autonomously conducts inspections on indoor electrical equipment such as the geographic information system room in the substations and various meters along specified routes. During the inspection process, the drone, equipped with laser radar and autonomous driving capabilities, maintains a safe distance of more than 1 meter from the equipment.

Automatic obstacle avoidance, real-time data transmission, and accurate hazard identification are some of the capabilities of the drone. After 15 minutes, the indoor drone can complete the inspection of 40 interval devices within the station.

"The indoor drone can achieve autonomous navigation, autonomous flight, and can inspect various indoor devices such as GIS, switchgear, secondary screen cabinets, voltage and current meters, and accurately collect key information," said Yang Min, the manager of the Hangbu substation. Through the application of indoor substation drones, remote supervision of equipment operation and intelligent status monitoring in substations' indoor space have been further enhanced, increasing efficiency by 67 percent compared to traditional inspection methods.

In recent years, the use of drones for substation inspections has become increasingly common. However, conventional drones face challenges in conducting inspections within indoor substations due to issues such as lack of satellite navigation signals and poor obstacle avoidance capabilities. Therefore, autonomous positioning is difficult to realize and inspection of blind spots is difficult to address. To overcome these technical challenges, State Grid Quzhou Power Supply Company established a technical team to explore the application of drones in indoor substations. After a year of team efforts, a drone inspection system suitable for the indoor substation was developed.

The lead creator of the team, Zhang Wenjun, explained that the system utilizes miniature drones as carriers and incorporates technologies such as autonomous positioning and navigation, obstacle avoidance and intelligent image recognition algorithms. It also has an intelligent drone landing pad. This enables indoor drones to perform three-dimensional reconstruction, autonomous positioning and navigation, collision protection, automatic inspection, real-time generation of inspection reports, and unmanned operation. This not only improves the timeliness and accuracy of inspections but also enriches the detection methods for indoor equipment, providing a new direction for the digital operation and maintenance of substations.