Research on Self‐Identification Technology of Zero‐Value Insulators in Distribution Lines Based on Electroluminescence Effect

To address the issue of low detection accuracy for zero‐value insulators in distribution lines, this study proposes a novel method for detecting these insulators based on the electroluminescence effect. Through theoretical analysis and experimentation, it was found that the luminescence intensity of ZnS:Cu electroluminescent material varies with coating thickness (optimal at 0.3 mm), filler concentration (optimal at 63.6%) and BaTiO 3 doping amount (20% by mass), exhibiting a trend of initially increasing and then decreasing. Furthermore, the luminescence intensity tends to saturate as the power‐frequency voltage increases, with the critical luminescence threshold electric field determined to be 300 kV/m. A simulation model of the electric field of insulator strings in distribution lines was developed, indicating that the optimal coating area is located at the junction between the steel foot and the cement, with a coating width of approximately 5 mm. Experimental results under normal operating conditions demonstrate that all insulator coatings emit weak light, whereas zero‐value insulator coatings do not emit any light. Finally, on‐site tests were conducted on a 10‐kV distribution line, where a zero‐value insulator was successfully identified. These results effectively validate the high detection accuracy and practical value of the proposed method.