| During the flow of steam in the steam turbine,as the pressure and temperature decrease,part of the steam will condense into small droplets.The existence of wet steam will seriously affect the safe and economic operation of steam turbines.It is of important theoretical and practical significance to carry out research on wet steam measurement technology.Based on the principle of microwave resonant cavity dielectric perturbation measurement,this paper designs and develops the software and hardware system of the steam humidity measurement device based on STM32 single-chip microcomputer,and conducts related tests and analysis.1.According to the characteristics of vapor-liquid two-phase flow in steam turbine,combined with the dielectric properties of wet steam,the principle of steam humidity measurement based on microwave resonant cavity is analyzed,and cylindrical microwave resonant cavity is selected as humidity measurement sensor.2.The hardware system of the measuring device adopts a modular design concept.The hardware system includes modules such as radio frequency,detection,analog-to-digital conversion,liquid crystal display,input,storage,communication,etc.,according to the function and performance requirements of each module,the component selection is carried out,Developed a humidity measuring device.3.The software system is divided into single-chip microcomputer bottom program and upper computer function software.Considering program maintenance and user interaction experience,modular programming is adopted.Develop single-chip computer program,realize the functions of radio frequency signal source control,AD conversion,detector detection control,Flash reading and writing,LED display,keyboard input,host computer communication,working status display and so on.The host computer software system is developed based on Visual Studio,which realizes the functions of communication with the measuring device,parameter setting,data processing,result display,and running state warning.4.After the development of the software and hardware system,the function of the humidity measurement system was debugged,the actual performance of each module was obtained,and the error was analyzed,and the software and hardware system development of the steam humidity measurement device was completed. |
