A New Method of Eliminating Interference Voltage in Wiring Circuit of Impulse Test Based on Simulation Calculation of CDEGS

When impulse grounding test is carried out to measure the potential of buried metallic pipeline, the existence of measuring wiring circuit will produce interference voltage, which will affect the accuracy of pipeline potential measurement result. Therefore, CDEGS is used to simulate the interference voltage generated by the wiring circuit. Firstly, a 1:1 replication real impulse grounding test model is established in CDEGS to simulate the pipeline potential without conductor layout, which is called $\mathrm{U}_{without}$ . Then, the simulation model with the connection arrangement of measuring equipment and conductors in the test is established to calculate the pipeline potential which is called $\mathrm{U}_{with}$ . Therefore, the interference voltage of the pipeline called $\mathrm{U}_{interference}$ equals $\mathrm{U}_{with}$ minus $\mathrm{U}_{without}$ in this form of wiring circuit. Finally, the pipeline potential measured in impulse grounding test is $\mathrm{U}_{pipeline}$ , the real potential of the pipeline should compensate for the interference voltage. The above method provides a new solution to eliminate the interference voltage.