Testing for High Voltage Compatibility
For a safe and interference-free application in proximity of high voltage power lines the quadrocopter was examined at the high voltage laboratory of the TU Dresden under the influence of up to 380kV. The quadrocopter is intended for the inspection of the technical equipment of high voltage overhead lines. Therefore it is necessary to fly as close to the power lines and pylons as possible to be able to detect even the smallest damages to isolators, wires and other components.
For a safe flight, it is essential that all navigation and control systems are working flawlessly and reliably. To achieve this, the quadrocopter is equipped with several independent sensors like GPS, barometric altitude sensor, magnetometer and an inertial measurement unit. All relevant telemetry data as well as live video from the photo or video camera is downlinked by radio transmission to the controller on the ground. These data links also have to work without disruption at all times.
A testing environment was set up at the high voltage laboratory of the TU Dresden to study the approach of the quadrocopter to the high voltage power line. To this the quadrocopter was mounted in about 5m height onto a moving platform, which was successively rolled towards the 380kV double-chain bundled conductor starting at a maximum distance of 10m. The shortest distance was only 3m. With this realistic experimental setup, the influence of the electrical field on all the sensors and control functions was tested thoroughly. In a second setup also the influence of the magnetic field was tested.
The pleasant result: All systems work perfectly. With this an important qualification for the safe and dependable application of the quadrocopter in the inspection and maintenance processes of high voltage overhead power lines was accomplished.