Design Of Wireless Temperature Measurement System For Power Cable Based On Zigbee

In recent years,in order to meet the growing demand for electricity in China,the scale of power system is expanding,and the use of power cables is also increasing,which brings great challenges to the maintenance of power cables.Since the power cable is the key equipment for power transmission in the power system,whether the power cable runs safely will directly affect the operating state of the power system.Therefore,it is necessary to take effective measures to monitor the operation status of power cables.During the operation of power cables,the surface temperature of cables will change whether there is a short circuit between the cables or to the ground,or the cables are under overload,or even the insulation breakdown of the cables.Therefore,the surface temperature of the cable often reflects the operation status of the cable,so the surface temperature of the cable can be monitored in real time in order to detect the abnormal operation of the cable in time.Based on this,this paper designs a wireless temperature measurement system for power cable to monitor the surface temperature of the cable.In this paper,the current research status of power cable temperature monitoring technology is analyzed,and from the practical engineering application,the design requirements of wireless temperature measurement system are put forward.At the same time,the overall design scheme of the system is determined according to the design requirements,and the selection of temperature sensor,microcontroller and wireless communication technology is completed.The wireless temperature measurement system designed in this paper is divided into three parts:temperature measurement node,temperature measurement receiving terminal and monitoring host.The temperature measurement node is mainly responsible for the collection.processing and forwarding of cable temperature data.The temperature measurement receiving terminal is mainly responsible for the transfer,display and storage of temperature data,as well as the temperature alarm.At the same time,it can query historical temperature information and the temperature alarm information of the cable.The monitoring host is mainly responsible for the request and reception.display and storage of the cable temperature data,as well as the temperature alarm.and can also query of the historical temperature information and the drawing of the historical temperature graph of the cable.This paper designs the wireless temperature measurement system from three aspects:hardware,algorithm and software.In terms of hardware,it mainly includes the circuit design of temperature measurement node,temperature measurement receiving terminal and monitoring host.According to their respective functions,the modular structure is used for design.In terms of algorithm,an IIR low-pass digital filter is designed to filter out the high frequency interference in the cable temperature signal.In terms of software,it mainly includes the software design of temperature measuring node,temperature measuring receiving terminal,and monitoring host.The former two software designs belong to the lower computer design.On the basis of their hardware design,the modular structure is also adopted,which is divided into main program and functional module program.The monitoring host software design belong to the upper computer software design,which is mainly divided into three parts:RS485 communication program design,GSM/GPRS communication program design and interface design.At the end of the paper,in order to test the actual operation effect of the wireless temperature measurement system,the system was tested for functions,including communication function test,temperature measurement function test,temperature alarm function test and monitoring software function test.The test results show that the communication between the temperature measurement receiving terminal and the temperature measurement node,also between the temperature measurement receiving terminal and the monitoring host,and between the monitoring host and the target mobile phone are normal.The test results also show that the accuracy of the system temperature measurement is high,and the temperature alarm can be carried out accurately and timely.And through the monitoring software,the real-time temperature.historical temperature and historical temperature curve of the cable can be viewed.as well as the alarm status of the system.