防護管内CVTケーブルにおけるアーク短絡故障時の圧力上昇・伝搬特性モデルの提案

抄録

In underground distribution systems, a CVT (Cross-Linked Polyethylene Insulated PVC Sheathed Triplex) cable is installed in a protective pipe. When a fault arc occurs on the CVT cable, instantly the pressure increases due to the high temperature of the arc and it propagates in the pipe. The pressure-rise and propagation may seriously damage to the pipe and connected power equipment. There are many different sizes of pipes and cables depending on the installation situations, and fault arc occurs under various conditions. Therefore, the simulation technique is effective for examining such pressure-rise and propagation in addition to short-circuit tests. The objective of this paper is to present a CFD (Computational Fluid Dynamics) modeling that can be used to evaluate the characteristics of the pressure-rise and propagation by the fault arc in the protective pipe. As a result, the pressure-rise waveforms by the CFD analysis were similar to those short-circuit test results. In addition, the dependences of maximum pressure-rise on the sizes of the CVT cable and arc current were simulated well. Therefore, the CFD modeling is sufficient for the study of the pressure-rise and propagation in the protective pipe.