| With the continuous development of the electricity industry,cables play an increasingly important role.Real-time and online monitoring the temperature of cables is worth studying since the excessive temperature of cables often causes failure and huge economic lost.In this paper,the comparison between the IEC calculation model and the numerical method was first conducted on the single cable and a single circuit cable to prove the effectiveness of the numerical method.The experiment shows that the deviation between the two methods is not very large when the cables are laying simply.Numerical method is more accurate as expanding the scales of cable laying.Then the simulation of temperature field on the cable trench is carried out by COMSOL software.The results,temperature of those cables located in the cable trench near the wall is higher,provide theoretical support for the sensors’ placement.It’s also helpful to analyze the effects of environmental factors on the temperature field distribution.A Zig Bee-based cable trench online monitoring system is established according to the simulation.It can collect temperature and humidity data of cables in real time.On the basis of project needs,the hardware system is used to select and design the circuits.The function of software system is designing and introducing the overall structure,including the acquisition and processing of node data,communication with the host computer and the display interface of the host computer.In order to obtain the accurate cable core temperature,WOA-BP intelligent algorithm is used to process the collected results.It leads to the core temperature value within the error tolerance.The whole monitoring system is finally tested at the cable trench site,and the result shows that online real-time monitoring system on temperature field of cables designed in this paper can collect the temperature and humidity in real-time and transfer the data to the upper computer for dynamic display.The average packet loss rate of the data is only0.066%,which is within the allowed range.It means this system supports efficient and accurate data transmission.This paper studies simulation of cable trench based on coupling of multi-physics,optimizes the algorithm on the cable conductive core prediction,promotes the application of cable online monitoring system in some degree. |
