Overvoltage Analysis of 110-kV Transmission Line with Extra-length for Qinghai-Tibet Railway: Part Ⅰ-Power Frequency Overvoltage

摘要

The 110-kV transmission line delivering energy for Qinghai-Tibet railway system has special length of 442 km with light load of only 14.87 MW. This long 110 kV transmission line would bring special overvoltage problems. First, the analysis model of power frequency overvoltage is built for transmission line and related power apparatus. Then, according to possible operation modes, the respective power frequency overvoltage is analyzed. The influential features of the source capacity, the length of the transmission line, and possible compensating modes and their characteristics of the system are all analyzed.