Power cable on-line insulated monitoring method based on traveling wave electric amount measurement

Abstract

The invention relates to a power cable on-line insulated monitoring method based on the traveling wave electric amount measurement, belonging to the field of the power system insulation technology. The method comprises: collecting the traveling wave electric amount measured on all the cable lines connected to the same generatrix of a transformer station in real time and synchronously monitoring whether perturbation occurs on all the cable lines or not; recording the occurrence time of the perturbation when the occurrence of perturbation on the cable lines is monitored; and comparing the characteristics of the traveling waves on all the cable lines and judging the cable line where the perturbation occurs; comparing whether the cable line where the last three perturbations occur is the samecable line; if yes, calculating the interval between the first perturbation and the third perturbation; comparing the calculated interval with the preset interval; the calculated interval being smaller than the preset interval, judging that the cable insulation is reduced and outputting the result of the cable on-line monitoring. The invention can reduce the cable line fault and ensure the safe and stable operation of the cable.

Description

technical field [0001] The invention belongs to the technical field of electric power system insulation, and in particular relates to a power cable insulation monitoring method. Background technique [0002] The quality of cable insulation is a key factor affecting the safe and reliable operation of cables. In order to ensure the safe and stable operation of the cable, it is necessary to diagnose the cable insulation in order to detect and respond to cable insulation defects as early as possible. The early cable insulation diagnosis technology was mainly a regular preventive test system. However, due to the long cable line and large capacitance, the preventive test is difficult, and the regular preventive test must be carried out with a power failure, resulting in power supply interruption, and can not be based on the cable insulation. The conditions are selectively tested, and all cables need to be tested, and each test will accelerate the deterioration of the cable insula...

AI Technical Summary

Problems solved by technology

Existing on-line monitoring technology adopts the method of adding signals except the ground wire current method, which is inconvenient to use in engineering applications, and the added signals are affected by the operation of the system

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