Abstract: It is very important to clear the fault point quickly when the catenary line breaks down to ensure the stable operation of highspeed train. This paper analyzes the existing problems of traditional fault location method for catenary and ranging method, a high-frequency transient fault location method that applys for complex circuits is put forward, when this method is in contact line fault location,it uses catenary line parameter model to comfirm wave speed and searches wave head by proper mathematical methods, then main branch fault classification is realized. A complex auto-transformer (AT) power supply line is selected for simulation verification, the simulation results show that the complex catenary fault location method based on high-frequency transientt has good system adaptability and provides a theoretical basis for the fault location of complex power supply lines.

    Key words: catenary; fault location; complex structure; high-frequency transient; AT power supply; direct supply line