| 摘要 |
FIELD: electricity.SUBSTANCE: they measure voltages and currents of pre-emergency and emergency modes. From the spectrum of signals of emergency mode they identify signals of the transient process, which are caused by damage occurrence. They identify specific frequencies of a standing wave of the transient process. They define the distance L from the start of the line to the place of the damage according to the formula L=C/4*P, where C - speed of propagation of the electromagnetic wave along the power transmission line, F - frequency of the standing wave of the transient process for the section from the start of the line to the place of the damage. For single-phase ground faults they additionally determine the distance L1 from the end of the line to the place of damage according to the formula L1=C/2*F1, where F1 - frequency of standing wave of the transient process for the section from the end of the line to the place of damage.EFFECT: higher accuracy of detection of the place of damage.2 cl, 3 dwg |
