Research On Hot Spot Temperature Monitoring Technology Of Transformer Winding

Transformer is an important equipment in power grid,the transformer can be stable operation is the key to decide whether or not a power system stable work.Winding hot spot temperature is one of the important parameters related to the transformer security,temperature is too high,the nature of the damage between transformer winding insulation materials,reduce its service life,easy to cause accidents,loss,so the monitoring of transformer winding hot spot temperature is of great importance.Considering the complex work environment and transformer can produce strong electromagnetic interference,so this topic using fiber Bragg grating(FBG)sensor measurement of transformer winding hot spot temperature,and based on the sensor used for monitoring of transformer winding hot spot temperature system is designed.Firstly,the common methods and research status of measuring hot spot temperature of transformer windings at home and abroad are analyzed,and the temperature measuring principle and demodulation mode of FBG are introduced.At the same time,using simulation software Ansys19.0 Maxwell and Fluent software module in 20 MVA,110 k V oil-immersed transformer electromagnetic field,fluid field,temperature field simulation analysis,it is concluded that the details of the transformer winding hot spot temperature,the simulation results of hot point temperature and load calculation results,To verify the exactness of the simulation,and analyzes the winding hot spot temperature under different ambient temperature.To provide a basis for the reasonable placement of FBG in actual measurement,make detection more effectively.Secondly,the hardware construction of the transformer winding hot spot temperature measurement system is completed.The appropriate optical components are selected and the working principle is briefly introduced.The FBGA demodulation module processes the detected optical signals and completes the hardware construction.Using USB interface part of hardware and the communication between the computer.On the computer by Labview software called dynamic link library DLL to complete the design of the upper machine,can realize,according to the temperature and wavelength beyond user setting threshold temperature alarm,and other functions.Finally,the hardware part and the software part are connected to complete the construction of the whole temperature measuring platform,and the calibration experiment and error analysis experiment are carried out.The fitting relationship between the central wavelength of FBG and the temperature is obtained and the feasibility of the temperature measuring platform is verified.