Calculation of Corrosion Depth of Wind Power Generators and AC Substations Induced by HVDC Grounding Electrode

At present, grounding potential rise is often used as the evaluation index to assess the electromagnetic intererence induced by HVDC grounding electrodes. It will lead to too stringent standards, for HVDC grounding electrodes are considered as long-term operation. Actuallly, HVDC grounding electrodes operates only in the test run stage, planned maintence and forced outage. In this paper corrosion depth is adopted as the evaluation index to assess the electromagnetic intererence. The method to calculate the corrosion depth of wind power generators and AC substation is described. The corrosion depth of windfarms and AC substation nearby Yanmenguan converter station is derived. The effects of material properties, distance and soil resistivity on corrosion depth are also studied.