Location Method for Interline and Grounded Faults of Double-Circuit Transmission Lines Based on Distributed Parameters

This paper presents a one-terminal fault-location method for interline and grounded faults of double-circuit transmission lines considering the distributed parameter. The influence of mutual inductances is taken into account in a six-sequence network of a distributed parameter model. And the compensation voltage with the help of a co-rotating zero-sequence compensation coefficient and reverse zero-sequence compensation coefficient is defined. Then, the phase and the amplitude of fault voltage are calculated by utilizing the relationship between measured reverse sequence current and fault reverse sequence current. Then, fault-location function is constructed by utilizing the measured voltage, measured current, and estimated fault voltage. Finally, the fault location is identified by solving the phase mutation point of fault-location function. The simulation results show that the method can be widely used for interline and grounded faults without the information of other substations. In addition, this method is merely influenced by fault location, transition resistance, source impedance, and is able to locate the fault accurately and is easy to implement.