Study On Fault Location Schemes For Transmission Lines Based On Transient Traveling-wave Information Fusion

To realize fault location reliably, fast and accurately, is important to restore power supply, which has always been the research hotspot and difficulty. Compared to the fault location methods that based on the steady-state variables, the methods based on the transient-state variables could realize more accurate results. As the signal processing technology, computer technology and hardware technology developing, it is possible to acquire and analysis the high-frequency signals generated by the fault. The methods based on the transient-state variables are making much more progress.Firstly, this thesis introduces the research status of fault location at home and aboard, and the advantages and disadvantages of various methods are analyzed in the meantime. Then the fault location theory is depicted, the refracting and reflecting law as well as attenuation characteristics in the transmission lines are analyzed so that the maximum detailed coefficients of wavelet transform are extracted as the feature variables of initial traveling-wave. At last, the fault location schemes based on the information fusion theory are proposed. In the data-level, the abnormal data is detected by the simulation and operational experience in the field, and then the phase-mode transform and wavelet transform are carried out in order to extract the feature variables. There are two parts in the feature-level, one is the fault section detection method where the fault feature variables are filtered by the topology and the other is the fault location based on the single-terminal arriving time difference between aerial and zero mode using artificial neutral network. In the decision-level, the double-terminal fault location algorithm based on the uploaded data is proposed by which the precise fault location is determined.The IEEE 14-Bus & IEEE 30-Bus System are simulated in the PSCAD/EMTDC program, and the fault location algorithm is carried out in MATLAB. The simulation results show that the scheme could realize high accurate fault location.