Abstract: This article uses finite element simulation calculation method to study the electric field distribu‍tion characteristics when zero value insulators appear in different insulator string types of 110 kV and 220 kV, and compares the sensitivity of composite field strength and axial field strength to zero value insula‍tors. The influence of zero value insulators on different string types is analyzed for single I suspension string, double II suspension string, and tension string.In addition, the influence of zero value insulator position and number on field strength distribution characteristics is quantitatively analyzed. The results show that the axial field strength is more sensitive to the occurrence of zero value insulators, and it is more suitable as a characteristic quantity for detecting zero value insulators. The presence of zero value insulators on the high-voltage side has the greatest impact on the electric field distribution. For the suspension double II string, the field strength on both sides should be measured separately to determine the location of zero value insulators. The decrease in field strength for two and three consecutive zero values is twice and 2.3 times that of a single zero valuerespectively.

Key words: zero value insulators, electric field distribution, axial field strength, finite element analysis, tension string