METHOD FOR PROTECTION OF ELECTRIC POWER LINES AND DEVICE FOR ITS REALIZATION Russian patent published in 2007 - IPC H02H3/32 

FIELD: protective systems of electric lines responding to the difference between currents, in which the values of voltage and current are compared at the respective points at different wires of the same, for example, current in the "go" and return conductors.

SUBSTANCE: the method consists in determination of the moment of current initiation in the "go" conductor, moment of current initiation in the return conductor, determination of the time interval between the mentioned moments, normalization of the actuating signal for disconnection of the electric power line at an excess of the given time interval of the threshold value. The circuitry of electric power line protection uses the first and second current transmitters, flip-flop, AND circuit, pulse oscillator, pulse counter, decoder, first and second electronic switches, the outputs of the first and second current transmitters are connected to the unity and zero setting inputs of the flip-flop, respectively whose direct output is connected to the first input of the AND circuit, whose second input is connected to the output of the pulse oscillator, the output of the and circuit is connected to the decoder input via the pulse counter, the output of the decoder is connected to the control inputs of the first and second electronic switches.

EFFECT: enhanced speed of response.

2 cl, 1 dwg