34 / 2018-08-21 20:39:18

Research on joint Optimization Method for Arrangement of Pipeline Cables

pipe laying; cables; temperature field; layout; optimization

With the continuous acceleration and development of urbanization, underground power cables have been widely used due to their deep underground, no space occupation, and pre-buried channels. Pipe laying is one of the important laying methods of urban distribution cables. It not only protects cables from external forces, but also effectively saves underground transmission channels. It is suitable for heavy traffic, crowded underground corridors, and a large number of cable loops. The arrangement of the cable groups in the pipe is different, and the electromagnetic influence between the cables is different, resulting in different temperature field distributions. Therefore, the arrangement of the cable group affects the current carrying capacity of the cables. In addition, when new cables need to be added to meet the increasing demand for electricity, new cables will also have an impact on the cable group temperature field, so it is necessary to optimize the cable group layout.
This paper proposes a combined simulation method based on MATLAB and COMSOL Multiphysics. This method controls the parameters variation of the model through MATLAB program, calculates the maximum temperature of the core of all layouts of the cable group, and finally obtains the arrangement method that makes the highest temperature of the core the lowest. In this paper, the combined simulation model of temperature field of distribution cables laying in 3*4 pipes is established by COMSOL and MATLAB, using the heat conduction, convection and radiation of three basic principle and differential equation of heat conduction way with the temperature of the hottest cable in the group being the lowest. The temperature field and the current carrying capacity are calculated under the full simulation of the actual environmental conditions, and the accurate, comprehensive and rapid optimization simulation calculation of all the layout modes under the multi-circuit quantity is realized, and the optimal arrangement of the cable group and the cable after the new cable are finally determined. The optimal arrangement of the group.
In this paper, the 6-circuit cable group is used as the initial cable group laid by the3*4 pipes. The correctness of the model is verified by calculating the temperature field and current carrying capacity. Through the MATLAB programs to control the parameters change of the model, the temperature field and the current carrying capacity of all the 6-circuit cables layouts under the pipe laying are calculated, and the lowest heat-dissipating arrangement of the cable cores in the cable group is obtained, which is determined to be optimal arrangement. Based on the optimal 6-circuits cable laying, add a new cable to calculate its temperature field, optimal layout and corresponding current carrying capacity. Comparing the maximum temperature value of the cable group core and the corresponding current carrying capacity under different layouts, the results show that the optimization of the cable group layout can not only significantly improve the current carrying capacity of the cable group, but also prolong the service life of the cable. It is of great significance for the long-term safe and economic operation of the cable, and can provide a reference for the planning stage before the cable group is laid.