Conversion Scheme Design of Power Supply Return Mode for Metro Connection Lines

Objective The metro lines connected by connection line may adopt different power supply current return modes. In order to improve the efficiency of train line transfer, it is necessary to set up the return mode conversion section within the connection line and design the return mode conversion scheme, which shall meet the demand of using the running rail and the return rail to return current. Method With Shaoxing Metro Line 1 (hereinafter referred to as "Line 1") and the first phase project of Shaoxing Metro Line 2 (hereinafter referred to as "Line 2") as examples, the overview of the two lines and details of the connection line are introduced. From the aspects of operation conditions, economy and engineering feasibility, three design schemes (Scheme 1, Scheme 2 and Scheme 3) for the power supply return mode conversion within the connection line are proposed, and their advantages and disadvantages are analyzed respectively. Result & Conclusion Scheme 3 is recommended. It can not only effectively solve the problem of train power loss, reduce the possibility of generating electrical conduction and foreign current between the two lines, but also optimize the train line transfer process and improve the efficiency.