In order to improve the traditional double terminal traveling waves ranging accuracy, based on the analysis of fault traveling wave propagation process, we propose a combination of T-type transmission line traveling wave method. First, the principle of distinction between the use of double-ended failure zone, and then judge each bus side to reach the second wave of the fault line or branch points of the reflected wave reflected wave, and finally by the principle of a single-ended fault location. The advantage of the method is to eliminate the effect of a given line length error and the line ends exactly traveling wave synchronization problem of the traditional double ended ranging precision. By PSCAD simulation analysis, compared with conventional double ended ranging method, T-type and transmission line traveling wave significantly improved accuracy.
