Identification of the Ignition Point of High Voltage Cable Trenches Based on Ceiling Temperature Distribution

Abstract

With the improvement of the development level of power systems, high voltage cable trenches are being widely used in power systems. The high voltage cable trench is characteristically strongly sealed, which makes it difficult to find a fire in the trench. In order to judge the development of an early cable fire, the relationship between the ceiling temperature distribution and the location of cable ignition points was studied. According to the idea of symmetry, this paper adopts the experimental method of symmetrical double ignition points, carries out several groups of longitudinally symmetrical cable fire combustion experiments with high voltage cable trenches as the carrier, and establishes an equation for calculating the fitness of the relationship between the ceiling temperature and the distance from the ignition point. The results show that the temperature measurement results of the 1:1 high voltage cable trench experimental platform are accurate; in the longitudinal direction, the ceiling temperature decreases from the ignition point to both sides, and the temperature change curve has obvious stage characteristics; within a range of 5 m from the expected ignition point, the average identification accuracy reaches 97.0%. In the early stage of a substation cable trench fire, the two-point temperature measurement and ignition point identification method of high voltage cable trenches based on ceiling temperature distribution proposed in this paper can effectively identify the location of the ignition point along the longitudinal direction of cable trench.

Keywords

• high voltage cable
• cable trench
• fire temperature
• ignition point
• identification