METHOD OF DETERMINING CURRENT DIRECTION Russian patent published in 2024 - IPC G01R19/30 

FIELD: electric power industry; measuring equipment.

SUBSTANCE: invention can be used to build a power direction relay. Method of identifying alternating current in a conductor using a closing reed switch, at which the reed switch is installed near the conductor, it is adjusted so that it operates and closes contacts at current I_act in the conductor. First actuation of the reed relay t₁, then the second actuation t₂ is additionally recorded, the time between the first and second actuation of the reed relay is measured, then its time is memorized. Further, the third actuation t₃ is recorded and the time between the second and third actuation is memorized. When time between previous and next actuations is equal to 0.01 seconds ±0.001, time t₁⁽ⁿ⁾ between the moment of the last closure t_act⁽ⁿ⁾ and the moment of return t_r⁽ⁿ⁾ is started and current amplitude is calculated from this time. In the case when the time between actuations is different from 0.01 seconds, then after the last fixation of the reed relay actuation, the memory is reset and the measurement cycle is restarted, then actuation of reed switch t_act⁽ⁿ⁺¹⁾ is recorded, astronomical time is memorized, second actuation of reed switch t_act⁽ⁿ⁺²⁾ in positive half-wave is recorded and astronomical time is memorized. Further, the time between actuations is calculated Δt₃=t_act⁽ⁿ⁺²⁾−t_act⁽ⁿ⁺¹⁾ and memorize it. If conditions are met 0.005<Δt₃<0.16, Δt₃>0.235, then this symbolizes the change in the direction of power in the opposite direction. If the above conditions are not met, then the cycle of fixation of response times t_act⁽ⁿ⁺¹⁾, t_act⁽ⁿ⁺²⁾ and calculation of Δt₃ is started again.

EFFECT: possibility of determining change in direction of current without using current transformers and voltage transformers.

1 cl, 7 dwg