The Self-Sensing Approaches And Experimental Research Of GMA

Giant magnetostrictive material(GMM) has lots of excellent performances, which make it have a broad application prospect in detection,sonar,magnetical, mechanical and electrical transducer fields.While the research for GMM is focused on the positive effect,the inverse effect and self-sensing technology for GMM are much less.In order to realize GMM works as an actuator and a sensor at the same time,a bending giant magnetostrictive actuator(WGMA) is designed,and the coupled electrical,magnetical and mechanical fields step model and equivalent circuit model are constructed.The finite element analysis of the coupled electrical,magnetical and mechanical fields for WGMA using ANSYS is carried out.The relational parameters of WGMA are calibrated according to experiments of positive and inverse effect of WGMA.The general principle of force sensor using GMM is proposed.Hysteresis angle is brought forward to calculate the size of non-linear hysteresis.Three approaches for self-sensing GMA are described in detail,and experimental studies are subsequently executed.In the first chapter,the developmental course,performance and features,current situation of the research and application at home and abroad of GMM are introduced. The features and research status of giant magnetostrictive self-sensing actuator are stated.The structure and significance of the research in the dissertation are interpreted.In the second chapter,three kinds of forms of magnetostrictive phenomenon are introduced,and the field-induced deformation is explained by magnetic domain theory and magnetostrictive model.Basic features of GMM are introduced in detail, and giant magnetostrictive self-sensing principle is interpreted using magnetic domain theory at last.In the third chapter,two kinds of structural forms for GMA are pointed out at first,and then the coupled electrical,magnetical and mechanical fields step model for WGMA suitable for reality is constructed.The equivalent circuit model for straight-moving GMA is established,which could be used to optimize the structural designing of GMA and realize self-ensing GMA.The finite element analysis of the coupled electrical,magnetical and mechanical fields for WGMA using ANSYS is carried out.In the fourth chapter,the experimental system for positive and inverse effect of WGMA,and the temperature control system of phase-change and water cooling are both described.The sensors used in the experiment are calibrated.The principle of positive and inverse effect of WGMA is analyzed.The static and dynamic experiments of positive and inverse effect of WGMA are carried out,and relational parameters of WGMA are calibrated according to those experiments.The general principle of force sensor using GMM is studied.To calculate the size of widespreadly non-linear hysteresis,hysteresis angle as a new concept is put forward,which is illustrated with one example in detail.In the fifth chapter,two approaches based on observing magnetic flux density and based on bridge circuit systematically apply for self-sensing GMA,and correspondingly experimental studies are carried out,and then the experimental results are analysed.A new approach for self-ensing GMA based on parameter identification is put forward.In the end,these three kinds of methods for self-sensing GMA are compared.In the sixth chapter,main work and key innovative points in the dissertation are summarized,and further research work is put forward.