FIELD: electric power industry.
SUBSTANCE: invention relates to the field of electric power engineering and can be used for analysis of damages and relay protection of a branched AC electric network. Method of relay protection of branched AC network consists in the fact that threshold evaluation bodies measure current level in line, determine its location within ranges I<0.05Inom, 0.05Inom≤I≤0.1Inom, I>0.1Inom, fixing the time mark value at the moment of the current passing through the protected element, through zero by means of internal clock of organs of threshold evaluation, synchronized from satellite navigation system, transmitting the fixed time mark value, current level information and the address of the current sensor installation location of the corresponding threshold evaluation organ to the data processing device, in which the difference between the moments of transitions through zero currents on both ends of each of the wires of each of the phases of each of the protected power lines is compared with the setting, comparing data on levels of currents at the ends of each phase of each line to generate permission to transmit a trip command and when the setpoint is exceeded and there is permission to transmit the command for disconnection, the power switches of the damaged power transmission line are disconnected.
EFFECT: faster operation and easier implementation.
3 cl, 3 dwg
