Calculation of Electric Field and Configuration of Grading Ring for Composite Tower of 500 kV AC Double Circuit Transmission Lines

Abstract

With the increasing number of transmission lines, the transmission corridor is more and more tense. In order to compress the line corridor, the composite tower of double circuit transmission line on the same tower has been paid attention to by the engineering circle. In order to ensure the safe and stable operation of composite tower, how to improve the potential distribution of each insulator and how to solve the serious problem of electric field distortion in each key position of composite tower are very important. In this paper, the double circuit linear tower on the same tower is taken as the research object. According to the design drawings, the calculation model of composite tower of AC 500 kV double circuit transmission line is established in the three-dimensional finite element analysis software ANSYS. Through the simulation calculation and analysis, the specific grading ring configuration scheme is determined by using the control variable method. Through the reasonable configuration of grading ring, the potential distribution of each insulator in the composite tower is effectively improved, and the field strength of each key position of the composite tower has met the requirements of field strength control, which improves the safety and reliability of the operation of the composite tower of EHV AC 500 kV double circuit transmission line.