Calculation and Influence Factor Analysis of Induced Voltage and Current in Double-Circuit Transmission Lines on the Same Tower Based on ATP-EMTP

Existing transmission lines are constrained by natural conditions, making it difficult to meet the growing power demand in urban development. The design of double-circuit transmission lines on the same tower is an effective solution to enhance transmission capacity and optimize design. This paper investigates the electromagnetic coupling mechanism of 500 kV double-circuit transmission lines on the same tower. Using the Alternative Transients Program - Electromagnetic Transients Program (ATP-EMTP) power system simulation software, a 500 kV double-circuit transmission line simulation model was established. The calculation methods for induced voltage and induced current under three different grounding conditions for the out-of-service line are analyzed, and the impact of line length and transposition on electrical parameters is discussed. The study found that line length has a significant impact on induced current but a smaller impact on induced voltage; transposition methods affect both induced voltage and current. Appropriate transposition methods can suppress induced voltage and current, enhancing the safety performance of the transmission line. This research has important reference value for the selection of grounding switches, fault location, and line design of doublecircuit transmission lines on the same tower.