Algorithms for blocking reclosing onto permanent faults and fault distance calculation in DC traction power supply system

Unlike the existing methods used to differentiate transient fault and permanent fault almost focus on the Information produced in the process of short circuit fault, the algorithm presented In this paper mainly utilizes the information after the protection apparatus open the circuit. To find the difference of the current between transient fault and permanent fault, many experiments were performed. The zero point symmetry B spline dyadic wavelet was used to extract the features. An algorithm for fault distance calculation is presented as well.