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With the expansion of high-voltage alternating current transmission networks, the widely used two-terminal traveling wave method faces several challenges in cable fault location. On one hand, the frequency dependent characteristics of longer cable transmission lines can significantly impact the accuracy of traveling wave propagation velocity. On the other hand, the processing of traveling wave signals obtained synchronously is also a crucial factor that requires attention. To enhance the performance of cable fault location, the principles of two-terminal traveling wave method need to be updated. Firstly, the cable model derived from the theory of wave propagation in multi-conductor systems is presented, which reflects the frequency dependent characteristics of the electrical parameters. Whereupon, an innovative cable traveling wave fault location scheme primarily composed of arrival time identification and instantaneous frequency calculation is proposed. Eventually, based on electromagnetic transient simulation software PSCAD/EMTDC, the robustness of the innovative cable fault location method against fault type, fault location, fault resistance, fault initial angle and earth resistivity issues is demonstrated. • Effective frequency-dependent cable model; • Higher cable fault location accuracy; • Higher robustness. [ABSTRACT FROM AUTHOR]

The key of traveling wave (TW) fault location (FL) method is the calculation of TW velocity and the calibration of TW wave head. In order to achieve high-precision FL, detailed transmission line (TL) parameters are needed to accurately calculate the TW velocity. In view of the problem that the existing high-precision TWFL methods are highly dependent on the calculation of TW velocity, the paper contributes to following aspects: (i) the mapping relationship between wavefront frequency and fault distance/fault pole is constructed; (ii) a neural network model suitable for FL and fault pole identification is designed, which is optimized by Particle Swarm Optimization (PSO) algorithm and Levenberg–Marquardt (L-M) algorithm; (iii) a complete FL scheme is proposed. In order to verify the FL accuracy of proposed method, an ± 800 kV bipolar high-voltage direct-current (HVDC) transmission system model is constructed using PSCAD/EMTDC. According to the simulation results, the errors of FL is less than 0.2 km and the accuracy of fault pole identification is 100%. For the problems of fault type, fault resistance and noise, the proposed method shows high robustness. • The relationship between frequency and fault location/fault pole is constructed. • Not depend on transmission line model parameters. • Higher fault location accuracy. • Robust against fault resistance. [ABSTRACT FROM AUTHOR]