Study on the Magnetic-machine Coupling Characteristics of Giant Magnetostrictive Actuator Based on the Free Energy Hysteresis Characteristics

A giant magnetostrictive actuator presents advantages such as large strain, high precision, and quick response. It is a hotly debated research topic in the field of micro drivers; however, the nonlinear intrinsic relationship between its output and input signals make it difficult to construct its nonlinear eigen model in the process of its practical application. Therefore, the motivation of this paper is to study the nonlinear magnetic–mechanical coupling characteristics of the giant magnetostrictive actuator, which is driven by free energy hysteresis characteristics. The nonlinear magnetic–mechanical coupling model under the weak form solution is deduced from the basic electromagnetic and mechanical theories, based on the distribution law of the axial magnetic field simulation, carried out to analyze the output displacement characteristics of the giant magnetostrictive actuator under preload. Experimental characterization of the device is also studied in the built experiment setup. Research results show that the experimental results coincide well with the simulation results, which show that the designed magnetic circuit for the giant magnetostrictive actuator is correct, and the coupling model of magnetic and machine of the giant magnetostrictive actuator based on the free energy hysteresis characteristics is reasonable.