The main purpose of this joint industrial R&D project was to perform detailed field measurements on selected pipeline segments in close vicinity to a High Voltage Direct Current (HVDC) transmission line during planned staged fault tests on the power line. Induced voltages on these pipelines were recorded during the HVDC staged fault process, which was conducted by the utility company. The measurement results from these tests were used for further validation or modification of an existing industrial guideline which focuses on the influence of HVDC power lines on metallic pipelines. Verification of future modelling results was another expected outcome of this study. A pre-field laboratory test was conducted to ensure accurate calibration and functionality of equipment prior to the actual staged fault field testing. To check the functionality of the digital triggering on the data logging unit and choose an appropriate triggering level and methodology, a typical touch voltage waveform based on previous simulation forecasts was used. The test setup during the HVDC staged fault testing consists of an arrangement of ground rods, a differential high voltage probe and the data logging unit used in order to capture the transient fault waveforms on the pipelines.
We conducted detailed induced voltage measurements on selected pipeline segments affected by a High Voltage Direct Current (HVDC) transmission line during planned staged faults on this power line. A detailed HVDC interference simulation study was also completed on these selected pipelines to evaluate induced touch voltages during staged fault condition. These pipelines were chosen based on the staged fault test locations and their relative geometry with HVDC power line. A comparison between measured and simulated results for further validation or modification of an existing industrial HVDC guideline, and verification of future modelling results were the primary concerns in this project.
HVDC transmission lines can couple in three different ways to parallel conductors: through mutual capacitance, mutual inductance, and through direct conduction.