Modelling on Novel Cable Traction Power Supply System and Power Distribution Analysis

Novel cable traction power supply system (NCTPSS) is a kind of long distance co-phase traction power supply system (TPSS), it can effectively solve problems caused by train's passing through electrical phase separation and improve utilization rate of regenerative energy in system, which is an ideal traction power supply mode. However, its structure is relatively complex due to cable power supply pattern, and internal power flow distribution mechanism still needs further study. In order to establish train-network coupling power flow calculation model, in this paper, two-port network model of each system component is established at first, then equivalent solid circuit model of the system is built by external cascade strategy and tearing nodal method. Then, power flow, the change of traction transformer power output and network voltage are analyzed under the condition that trains work in traction and regenerative braking condition, based on actual train operation schedule. The research shows that the proposed model can accurately calculate and detailed reflect electrical characteristics of NCTPSS, traction transformer capacity is effectively decreased compared with that needed in existing TPSS; Regenerative power can feed back to entire cable traction network and be reused by traction trains with high utilization rate inside NCTPSS.