FIELD: electricity.
SUBSTANCE: models of two parts of a feeder are compiled, the first - from the observation place to the place of supposed fault and the second - from the place of supposed fault to the feeder end, the first part of the feeder is simulated using straight line and a zero sequence, and the second one - using only a zero sequence, non-zero components of the registered currents and voltage of the damaged phase in the place of supposed fault are converted into the direct sequence models into a non-zero component of voltage of the damaged phase, the zero components of the registered currents and voltages are converted into zero sequence models of the first part of the feeder into zero sequence voltage in the place of supposed fault and into zero sequence current to this place, two named voltages are summarised, forming a voltage of the damaged phase in the place of supposed fault, the zero sequence voltage is fed in the place of supposed fault to the input of the zero sequence model of the second part of the feeder and the current on its input is fixed which is subtracted from the zero sequence current to this place, forming current of supposed fault, voltage and current are multiplied in a place of supposed fault, forming a signal of instant power of the supposed place of short circuit, the sign of this signal is determined and a real short circuit is fixed in the place where the named signal during its change remains non-negative.
EFFECT: improving accuracy.
10 dwg
