Fault location based on global search of minimum phase difference for high voltage transmission lines

A single-end fault location method is proposed for dual-phase grounding fault, which estimates the residual voltage of lines and the current of faulty branch according to the voltages and currents from protections and locates the fault according to the minimum phase angle difference between the residual voltage and fault component current. With the consideration of distributed capacitance, Bergeron model is applied to calculate the voltage distribution over whole line. The equation of transmission line is established based on the modulus space by phase-modulus conversion and the one-dimensional global search is proposed to estimate the distribution of voltage and current over whole line. Results of EMTDC simulation show that, the proposed algorithm locates the fault accurately for different transition resistances, different fault locations and different fault angles, and the maximum error is within 0.5%.