Abstract: AT traction power supply has been widely used in high-speed railway traction network. When short-circuit faults occur in the power supply system, if the faults are not removed and the power supply does not continue in a stable way as soon as possible, the normal operation of railway system could be affected and serious safety accidents could happen. In this paper, the traction power supply mode commonly used in high-speed railway-all-parallel AT power supply is introduced. The electrical calculation and theoretical analysis of T-F short-circuit faults happening in the traction network are carried out, and the principle of fault location based on “the current ratio of paralleling lines” is put forward, which is highly accurate and not affected by external factors. Then, according to the actual operating line, the author sets up parameters of the power supply traction network and establishes the simulation model in MATLAB. After making simulation analysis of the principle of short-circuit fault location, the simulated right results are obtained which verifies the correctness of the above theoretical analysis.

    Key words: AT traction power supply; T-F short-circuit; fault location; electrified railway