High-voltage power cable leakage current separation and detection method

Abstract

The invention discloses a high-voltage power cable leakage current separation and detection method which comprises the following steps of: S1: respectively mounting current transformers and voltage transformers at the head end and the tail end of each phase of a three-phase power cable in advance; S2: for each phase of the three-phase power cable, acquiring a head end voltage measured by the voltage transformer at the head end of the phase and a tail end voltage measured by the voltage transformer at the tail end of the phase; S3: rising an experimental voltage to 1.06 times of a rated workingvoltage of a detected object; S4: switching the phases, changing over a switch and respectively reading secondary readings; and S5: intercepting a relatively large value in the secondary readings asa detected leakage current value. According to the invention, by carrying out current separation and detection, the ageing condition of the cable is convenient to know, a case of causing a power gridaccident by cable ageing is avoided, detection efficiency is improved, meanwhile, detection steps are reduced, and a detection result is ensured.

Description

technical field [0001] The invention relates to the technical field of high-voltage power cables, in particular to a separation and detection method for leakage current of high-voltage power cables. Background technique [0002] Power cables are cables used to transmit and distribute electric energy. Power cables are often used in urban underground power grids, power station lead lines, internal power supply in industrial and mining enterprises, and underwater transmission lines across rivers and seas. In power lines, the proportion of cables is gradually increasing. Power cables are cable products used to transmit and distribute high-power electric energy in the backbone lines of power systems, including 1-500KV and above various voltage levels, various insulated power cables, and the basic structure of power cables consists of wire cores (conductors) ), insulation layer, shielding layer and protective layer. The power cable has less land occupation, high reliability, more ...

AI Technical Summary

Problems solved by technology

[0004] The operation experience of a large number of XLPE cables shows that cable line faults are an important cause of power grid accidents. After the cables are put into use, they will not only be affected by electric field, mechanical and thermal effects, but also be affected by environmental factors. Under the action of the cable, the cable is prone to aging, and the thermal aging of the cable will greatly increase the probability of cable line failure. After the cable fails, it is necessary to shunt and detect the leaked current. However, the existing detection methods are not only poor in detection effect, Moreover, it is time-consuming and labor-intensive, and has great limitations. Therefore, we propose a high-voltage power cable leakage current separation and detection method to solve the above problems