Fault Location Based On Double Terminal's Information Of High Voltage Transmission Line

With the development of power system and equipped capacitor, the more and more HV transmission lines have been constructed which take charge in transporting electrical energy in power system. Once faults occur on transmission lines, it is difficult to find out unclear faults. So accurate fault location for HV transmission lines can greatly lessen the time needed for patrolling line and quicken the power restoration. It is signifycantly important to the secure and economic of power system.The algorithms of fault location can be divided into single-terminal location and two-terminal location according to mearsurment information. When the single-terminal location algorithm based on the fundamental frequency component is used to locate the fault position, it is impossible to eliminate the influence of transition resistance and equivalent impedance variation of remote source. With the development of communication and computer network techniques, two-terminal location has become more attractive which can eliminate the influence of transition resistance and equivalent impedance variation of remote source in theory.After analyzing kinds of traditional fault location methods based on fault fundamental component, this paper proposed a developed two-terminal fault location method based on distributed parameters. This method can eliminate the influence of transition resistance, types of faults and unsyschronize angle. It can reject uncorrect solution effectively.At meantime, this paper proposed a new fault location algorithm for double circuit transmission lines, which can ignore inductance mutual. This method can also eliminate the influence of transition resistance, types of faults and unsyschronize angle. The simulation of ATP shows that the new algorithm is of high accuracy.In practical situation, double circuit transmission line always goes with single transmission line because of landform. So this paper proposed a new general fault location algorithm for this case. ATP simulation shows that its accuracy is acceptable.According to the algorithm above, the fault location software based on COMTRADE has been developed. The core of software is COM module that is widely used for upgrading software and expanding automation of electric power system distribution.