Abstract: Traditional rail transit projects generally prepare for the conditions required for the extension line signal system to connect to the existing line from the beginning of the initial construction phase. However, accessing existing lines through the method of connection in specific sections faces more complex on-site conditions. In order to reliably and efficiently achieve the transformation of connecting the signal system to the existing line, while ensuring that the normal operation of the existing line is not affected during the transition period, a plan has been presented in this paper. Taking the East Extension Line Project of Changsha Metro Line S2  as an example (which is a maglev line), this paper analyzes the engineering difficulties as the starting point, and conducts research and analysis on project implementation timing, construction debugging difficulties, and coordination and cooperation ability. A renovation plan for connecting the signal system to existing lines has been proposed, providing a reference for future extension line renovation projects that adopt the method of connection in specific sections to access existing lines.

Key words: signal system, maglev, existing line renovation, connection in specific section

摘要： 传统轨道交通项目一般在先期工程建设之初就预留延伸线信号系统接入既有线的条件，而区间接轨方式接入既有线面临更加复杂的现场条件。为可靠、高效地实现信号系统接入既有线改造，同时不影响既有线在过渡期间的正常运营，结合长沙磁浮东延线工程实例，以工程难点为切入点，围绕工程实施时序、施工调试难度、协调配合能力方面进行研究分析，提出信号系统接入既有线的改造实施方案，为后续采用区间接轨方式的延伸线接入改造项目提供参考。

关键词: 信号系统, 磁浮, 既有线改造, 区间接轨