Study of test method for accelerated electrolytic corrosion of iron caps of DC disc porcelain insulators

In order to provide reference for the operation and maintenance of porcelain insulators on DC transmission lines, the test method for electrolytic corrosion of iron caps was studied in National Engineering Laboratory for Ultra High Voltage Engineering Technology (Kunming) of China, with XZP2-300 porcelain insulators that had no protection zinc collar. The results indicated that the spray water method could simulate the field corrosion condition when the conductivity and volume flow rate were 12 mS/cm and 6-12 L/h respectively, and the differences in the length, width and depth of corrosion area between the test results and the field condition were less than 8%. Besides, the differences in the test results with spray water method from two experimenters were less than 7%. Our study demonstrated that the spray water method proposed in this paper had good equivalence and repeatability, which could be used to research the electrolytic corrosion problem of iron caps of porcelain insulator on HVDC transmission line.