摘要 |
FIELD: electricity.SUBSTANCE: invention relates to electrical engineering, and namely, to system automatic controls and relay protection. The assigned task is achieved by the current protection method lying in actuation of the current protection when a current-dependent values exceeds the setpoint at the site of its connection; the setpoint is selected with consideration of modelling or statistic calculations of equivalent circuit diagrams in operating conditions and short-circuit conditions. According to the suggested method current phase is used with amplitude and the value compared with the setpoint value and the setpoint itself are calculated from the logarithm ratio for joint probability density of amplitude and current phase in operating conditions and short-circuit conditions.EFFECT: development of the current protection method featured by high selectivity.5 dwg, 1 tbl |