FIELD: relay protection of distribution systems and high-voltage power transmission lines. SUBSTANCE: method depends on mechanisms characteristic of relationships between energies of emergency addends of their no-zero components and zero-sequence components. In faulty phases, difference between energies of emergency addends and energy of zero-sequence component exceeds energy of no-zero component. In case of phase-to-phase fault, when zero sequence is negligible, levels of emergency energies of separate phases are checked. EFFECT: improved selectivity of method due to using energy of emergency addends of electric quantities as information parameters. 4 dwg
