Fault location using measurements of current and voltage from one end of a line

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A method to locate a fault from one end of a section of a power line utilizing measurements of current, voltage and angles between the phases at a first end of said section. Symmetrical components of currents are calculated for the current and voltage measurement at the first end. A value of impedance is calculated for an extra link between the terminals with the impedance for the positive sequence equal to : (Z_1⁢ ⁢LB&⁢AB=Z_1⁢LB⁢Z_1⁢ABZ_1⁢LB+Z_1⁢AB)⁢ ⁢where⁢ : Z1AB=impedance for the positive sequence of the extra link, Z1LA=positive-sequence impedance of the healthy line. A compensation is determined for the shunt capacitance with the aid of an equation of the form : [in-line-formulae]B2comp—1(dcomp—1)2+B1comp—1dcomp—1+B0comp—1=0 where : [/in-line-formulae][in-line-formulae]B2comp—1=A2—Recomp—1A00—Imcomp—1−A2—Imcomp—1A00—Recomp—1 [/in-line-formulae][in-line-formulae]B1comp—1=A1—Recomp—1A00—Imcomp—1−A1—Imcomp—1A00—Recomp—1 [/in-line-formulae][in-line-formulae]B0comp—1=A0—Recomp—1A00—Imcomp—1−A0—Imcomp—1A00—Recomp—1. [/in-line-formulae] The zero-sequence current is determined from the healthy line of a section of parallel power lines. A distance to a fault is calculated for the parallel line section. The distance to the fault from the first end is calculated using a quadratic equation of the form : [in-line-formulae]B2d2+B1d+B0=0 where : [/in-line-formulae][in-line-formulae]B2=A2—ReA00—Im−A2—ImA00—Re [/in-line-formulae][in-line-formulae]B1=A1—ReA00—Im−A1—ImA00—Re [/in-line-formulae][in-line-formulae]B0=A0—ReA00—Im−A0—ImA00—Re. [/in-line-formulae]