Studies On Advanced Fault Record And Monitor System And High Accurate Fault Location In Power Systems

Because of the power system interconnection and deregulation, it is very important to study and realize continued recoding of steady data and dynamic process and synchronous measurement so as to analyze wide area, long process and developing faults. The accuracy of fault location and detection can be improved by using two-terminal measurements and wavelet analysis. It is helpful to improve the power system reliability. Therefore, the advanced technique for power system fault recording, accurate fault location algorithm and fault line detecting method for ungrounded systems are deeply studied in the dissertation. Main studies and contributions are given as following.An advanced fault record and monitor system for power systems has been designed and developed. Based on the advanced ETX embedded modularization CPU, 32 bit float DSP TMS320C32, large-scale CPLD, multiple CPU parallel processing, GPS synchronous clock technique and embedded real time operation system of OSII and QNX, it has high online processing and communication speed, reasonable function distribution, compact construction, easy extension and strong capability of anti-interference.To meet the demand of power system development, many advanced technique are adopted in the device. The capacity of data process and reliability is increased because of embedded integrative industrial design. Frequency tracking and synchronous phasor measurement techniques have been adopted to meet the power system demand of wide area measurement and stability analysis. The accuracy of measurement has been increased much more because of vector revising technique of analogue channel. The uniform analysis technique of steady and dynamic data has been realized to ensure the analysis to wide area, long process and developing faults. A new single terminal fault location method based on distribute capacitance compensation is proposed to ensure the precision of fault location.The single-terminal fault location method has theoretic error that is hard to overcome. Thus, the two-terminal fault location method, which can increase accuracy of fault location, is deeply studied. The fault location and synchronous sample error between two terminals can be solved using positive and negative two terminal voltages and currents based on the distribution parameter model of transmission line. The least-squares iterative method is employed to solve the redundancy equations. The test results show that the convergence is good and the accuracy is high. The influence of transmission line parameters is given and the results show that the accuracy of the transmission line parameter is an important factor that impacts precision of fault location. Based on the distribution parameter model of transmission line, a least-squares adaptive algorithm for fault location based on parameter estimation of transmission line is proposed. Using the data provided by fault recorders equipped at both ends of the transmission line, the on-line parameter estimation of the transmission line can be...