Research On Motor Temperature Measurement System Based On Fiber Bragg Grating

Motors are widely used in daily industrial and agricultural production.It is very important to ensure the safe and reliable operation of motors for production,life and economy.The change of the internal temperature of the motor is one of the important indicators that affect the performance of the motor.If the temperature of the motor is too high,the service life of the motor will be shortened and its safe and reliable operation will be affected.Therefore,accurate detection of the temperature distribution in the motor has important guiding significance for the use of the motor,the security guarantee and reasonable design.In order to measure the temperature variation of the internal parts of the motor under normal operating conditions,the fiber Bragg grating sensors are used to realize the internal temperature measurement of the motor.The FBG's strong resistance to electromagnetic interference,good insulation,high measurement sensitivity,and easy implementation of distributed multi-point measurement make it ideal for measuring the temperature inside the motor.Experiments show that the temperature measurement of the motor based on fiber grating sensing technology not only has strong anti-electromagnetic interference,but also can achieve multi-point distributed temperature measurement.It is an ideal temperature measurement method in a complex environment.Firstly,the status quo of the research on the temperature field of the motor and the commonly used calculation methods of the temperature field at home and abroad are analyzed in detail.After comparing and analyzing the development of fiber gratings at home and abroad,motor temperature measurement methods and various FBG demodulation methods.The motor temperature measurement system was proposed based on the technology of fiber grating temperature measurement.Using ANSYS16.0 Workbench finite element analysis software to build the motor model,simulation and anslysis the temperature distribution of the stator and rotor inside the motor,according to the simulation results,we can not only determine the temperature range of the required sensor,but also can determine a reasonable position to put fiber grating and provide a basis for the experiment.Then complete the hardware part of the system construction work.The relevant principles or characteristics of the main components(ASE light source,FBG,optical circulator,fiber optic connector,etc.)used in the system hardware are described in detail.The conversion of light-electric signals is completed inside the demodulation module,and data acquisition is completed through the control circuit.Realize the communication between the hardware part and the upper computer through USB,and transfer the data collected by the hardware part to the PC for further data processing.The data processing interface is written in the Labview graphical programming language on the PC.The interface mainly includes device connection,data acquisition,waveform and temperature value display,data storage and other functional modules.Finally,the hardware part and the software part of the system are connected to complete the construction,and the system experiment is conducted.The experimental results show that the wavelength and temperature of the FBG show a linear relationship and prove that the temperature measurement system is feasible.