| The magnetostrictive displacement sensor has the advantages of high precision,strong stability and good repeatability,and is widely used in petroleum,chemical,aviation and other fields.In this paper,a domestically-made waveguide wire(Fe-Ni)is used as a sensitive component,and a high-precision,low-cost magnetostrictive displacement sensor with a HART communication interface has been developed.According to the theory of magnetostrictive effect,the domestic waveguide wire sensitive component is used to build an experimental platform for detecting magnetostrictive effect,and the software and hardware system design of magnetostrictive displacement sensor is completed.The excitation pulse amplifying circuit,the torsional wave signal receiving and processing circuit,the 4-20 mA current loop,the HART modulation and demodulation circuit,the display circuit,the system power supply and the auxiliary circuit are designed.IAR for 430 is the software development platform,adopting the modular idea,software design for each module,magnetostrictive effect excitation circuit module,torsion wave signal processing module,AD421 current loop module,HART communication module.Through the HART communication circuit design,it can realize digital signal communication on the 4-20 mA analog current signal transmission line.The subject has carried out in-depth experimental analysis and research on the influence of parameters such as induction coil,excitation pulse width and current based on magnetostrictive effect on torsional waves,which laid the foundation for the smooth progress of the subject.The experimental results show that the sensor has high test accuracy,high cost performance,stable and reliable system,and has reached the design goal. |
