Research of Geoelectric Field Observation Interference with Different Electrode Arrangements from UHVDC Power Lines

The interference from UHVDC power lines is a key issue puzzling the geo-electric field observation in seismic station. According to the working principle of geo-electric field observation instrument, the interference reason on geo-electric field observation is analyzed, which potential distribution of the electrodes in soil of geo-electric field observation instrument is changed by the ground current from ground electrode of power line. Based on the different electrode arrangements, the electric field calculation model at different positions away from ground electrode is established, and thus the variation could be acquired. The results show that interference values are affected due to the electrode spans and the electrode arrangement directions, and there has the minimum interference when the electrode span is 100 m or the angle between line of two electrodes and radial line of ground electrode is 45°.