METHOD FOR DETERMINATION OF DAMAGED POINT AT SHORT-CIRCUITING IN AERIAL CABLE LINES OF DIRECT-CURRENT POWER TRANSMISSION Russian patent published in 2014 - IPC H02H3/16 G01R31/08 

FIELD: electricity.

SUBSTANCE: method lies in registration of voltage curve shape for the damaged transmission pole, determination of temporary voltage reduction at the pole below the setting U _set up to 0, comparison of this time interval with the preset value t _cl, when this value is exceeded an output signal is shaped at the first protection channel signalling damage at the aerial segment and when the time interval is less or equal to t _cl an output signal is shaped at the first protection channel signalling damage at the cable section of the direct-current power transmission line; calculation of frequency component of voltage change with the biggest amplitude against the first points of the voltage curve transition through 0, comparison of this frequency component with the preset value f_mincl, when this value is exceeded an output signal is shaped at the second protection channel signalling damage at the cable section and when values of the frequency component are less or equal to f_mincl, but bigger than f_minal, then an output signal is shaped at the second protection channel signalling damage at the aerial segment of the direct-current line. The protective output signal is shaped for cut-off of the respective half-circuit without automatic reclosure at simultaneous delivery of the signals from the first and second channels that register detected damages at the cable section of the line. The protective output signal is shaped for cut-off of the respective half-circuit with automatic reclosure at simultaneous delivery of the signals from the first and second channels that register detected damages at the aerial section of the line.

EFFECT: higher reliability in operation of direct-current power transmission line.

5 dwg