Why does the temperature increase of the cable insulation layer affect the use of the cable
In the era of rapid development of modern electricity, high-voltage equipment and insulation technology are rapidly developing. Especially in high-voltage systems, insulation quality issues have always been a concern. Due to strict usage conditions and environmental impacts, the insulation of high-voltage equipment (such as cables, insulators, transformers, etc.) may be subjected to pressure, leading to premature aging and damage, which may result in unwanted power outages. Therefore, for high working conditions such as high temperature, overvoltage, and pollution, precise analysis and measurement of the electrical parameters of high-voltage equipment should be carried out. Usually, dielectric loss factor or tangent measurement is performed on most insulation materials, which provides ideas about good insulation conditions. Especially for high-voltage cables, they play an important role in distribution systems, and the dielectric loss of insulation materials should be carefully analyzed at different temperatures to avoid electrical faults and malfunctions. The dielectric loss factor measurement of 12/20 kV single core cross-linked polyethylene (XLPE) insulated high-voltage cables was carried out at different conductor temperatures from 20 ° C to 90 ° C, with a temperature step of 10 ° C. The test results indicate that the conductor temperature significantly affects the dielectric loss factor of cable insulation. Single core cross-linked polyethylene (XLPE) insulated high-voltage cables are tested at different conductor temperatures from 20 ° C to 90 ° C, with a temperature step of 10 ° C. The test results indicate that the conductor temperature significantly affects the dielectric loss factor of cable insulation. Single core cross-linked polyethylene (XLPE) insulated high-voltage cables are tested at different conductor temperatures from 20 ° C to 90 ° C, with a temperature step of 10 ° C. The test results indicate that the conductor temperature significantly affects the dielectric loss factor of cable insulation.
Why do 10kV/20kV cables need temperature measurement
In a 10kV/20kV cable distribution network, the cable terminal is a weak link compared to the cable body, and is a short board for the safe operation of cable lines. Before the cable head malfunctions in actual operation, there is often a process of heating up, accelerating insulation aging, and ultimately causing breakdown and short circuit “shooting”. During this period, the temperature of the cable head will be much higher than normal and will last for a relatively long period of time. Therefore, theoretically, possible defects can be detected in a timely manner by regularly measuring the temperature of the cable terminal.
At present, operating units mainly rely on infrared thermometers, handheld partial discharge testers, and other equipment to regularly inspect power distribution equipment and cable heads. However, these devices are limited by the enclosed state of fully insulated and touchable elbow cable heads, and cannot test the true temperature and partial discharge situation at the copper terminals of the cable heads.
What are the advantages of cable fiber optic temperature measurement system
The cable fluorescence fiber optic temperature measurement system is used for temperature detection of high-voltage cable terminals. The fluorescence fiber optic thermometer includes a thermometer host and a fluorescence fiber optic temperature measurement probe. The temperature measurement probe is embedded in the insulation plug of the cable head, and the fluorescence fiber optic temperature measurement instrument is interconnected with the fluorescence fiber optic temperature measurement probe through the insulation plug of the cable head through the temperature measurement fiber. The fluorescence fiber optic temperature probe monitors the reflection time at different temperatures to determine the temperature. By pouring the fluorescence temperature probe inside the insulation plug of the cable head, the true temperature inside the cable head can be detected. Solved the problem of traditional temperature measurement technology being unable to control the actual temperature inside the cable elbow head; It can accurately understand the internal temperature situation of the cable elbow head, and the digital fluorescence fiber optic thermometer can digitally and intuitively display the temperature inside each cable head, which can timely shut down and repair the abnormal temperature of the ring main cabinet. Provide temperature protection for cable network operators.