Optimization of 3D magnetic field of double coil giant magnetostrictive transducer
                                                                    XU Yuefeng1,2, HUANG Wenmei1,2
(1.State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Hebei University of Technology,Tianjin 300130, China; 2.Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province, Hebei University of Technology, Tianjin 300130, China)

Abstract: Aiming at the performance of giant magnetostrictive transducer and its magnetic field environment, the magnetic field intensity, magnetic leakage and magnetic field uniformity of giant magnetostrictive material (GMM) rod of giant magnetostrictive transducer were studied. Based on GMM, a doublecoil transducer was designed. On the basis of analyzing the characteristics of GMM and the working principle of giant magnetostrictive transducer, the design principles of increasing the magnetic field intensity of GMM rod, reducing magnetic leakage and improving the uniformity of magnetic field were put forward. The magnetic field strength in the direction of the rod axis was used as the evaluation standard. The threedimensional magnetic field simulation of the doublecoil giant magnetostrictive transducer was performed by COMSOL Multiphysic. The influence of the structure parameters of the upper and lower magnets and the magnetic conduction loop on the mean value and the uniformity of the magnetic field of the giant magnetostrictive transducer was analyzed. The results indicate that with the increase of the radius of the magnetizer, the uniformity of the magnetic field of the GMM rod increases first and then the amplitude increases slowly. The average value of the magnetic field first changes and then decreases sharply. With the increase of the relative permeability of the magnetic circuit, the magnetic field strength of the GMM rod significantly increased, when the relative magnetic permeability reaches 1 500, the average value of the magnetic field strength tends to be balanced. After optimization, the uniformity of the magnetic field is increased from 59.7% to 90.5%, an increase of 30.8%.

Key words: giant magnetostrictive transducer; double coil; finite element analysis; 3D magnetic field; TerfenolD