A complex cable-overhead hybrid transmission line was used in the Zhenhai-Zhoushan 500kV line project in East China, which cannot be located accurately in the event of a fault and cannot automatic reclosing the failure of the overhead line. This paper proposes a fault location scheme which is suitable for cable-overhead hybrid transmission lines. In the scheme, the positive sequence fault component is adopted, the accurate parameters of each section of the hybrid line are used, and the voltage amplitude of each point along the line is calculated by using the electrical quantities on both sides of the line. According to the characteristics that the voltage amplitude of the fault location calculated by the electrical quantity on both sides is equal, the fault location is accurately calculated. According to the requirements of reclosing in practical engineering, a fault location section location method is proposed. The voltage amplitude at the junction of cable and overhead line is calculated with the electrical quantities on both sides of the line, and the fault section can be located by comparing the two voltage amplitudes. After the fault section is located, it can prevent the malfunction of reclosing when the fault occurs in the cable. The simulation results show that the accuracy parameters of each section of the Zhenhai-Zhoushan overhead-submarine hybrid line
