The Energy Harvesting And The Nonlinear Dynamics Research Of The Bistable Piezoelectric Cantilever Beam

With the development of science and technology and the gradually attention of people paid to the living environment, the new energy technology has become a research focus for many researchers. The piezoelectric energy harvesting which based on vibration as a highlight of the new energy field has attracted much attention in recent years. The piezoelectric energy harvesting technology has the advantages of quick response, pollution-free, long service life, simple structure and easy assembling.The technology combines knowledge of many disciplines, such as mechanics,materials, and electronics. In this paper, the bistable piezoelectric cantilever energy harvester is studied as the research object, and the nonlinear dynamic response and power generation capacity are analyzed.In this paper, both theoretical model and experiment result are studied, the power generation capacities of the bistable piezoelectric cantilever beam and that of the monostable structure are compared; the advantages of power generation for the bistable structure are analyzed. We design a series of optimization models based on the traditional bistable piezoelectric cantilever beam and analysis the power generation capacity of the optimization models. We experimental study on the nonlinear dynamics of traditional bistable piezoelectric cantilever beam. The electromechanical coupling equation of the traditional bistable piezoelectric cantilever beam is derived, the power generation capacity and dynamic response are analyzed,the theoretical analysis and the experimental results are compared. Then, we experimental study on the power generation capacity and the nonlinear dynamic response of the longitudinal auxiliary magnetic bistable piezoelectric cantilever beam.The dynamic equation of the longitudinal auxiliary magnetic bistable piezoelectric cantilever beam is numerical analyzed, the power generation capacity and the nonlinear dynamic response of the system are studied, and the experimental results and theoretical model are compared. This paper consists of the following sections.(1) The power generation capacity of the monostable piezoelectric cantilever beam and that of the bistable piezoelectric cantilever beam are compared, a series of optimized models are given based on the traditional bistable piezoelectric cantilever beam, and the power generation capacity of the different optimized models are compared.(2) The nonlinear dynamic behavior of the traditional bistable piezoelectric cantilever beam is experimental studied. The stiffness of the system is analyzed.According to the forward sweep and reverse sweep of the displacement, the soft spring property or hard spring property is studied. The influence of the external excitation and the distance between the magnets on the dynamic behavior of thesystem is analyzed.(3) The dynamic equation of the system considering the nonlinear curvature and nonlinear magnetic force is derived based on Hamilton's principle. Numerical simulation of the dynamic equation is considered, the results analysis the influence of parameters on the dynamic characteristics of the system by the waveform, the phase portraits and Poincare map.(4) The nonlinear dynamics of the longitudinal auxiliary magnetic bistable piezoelectric cantilever beam is experimental studied. The stiffness of the system is analyzed. According to the forward sweep and reverse sweep of the displacement, the soft spring property or hard spring property is studied. The influence of the external excitation, the distance between the primary magnets and the distance between the primary magnet and the auxiliary magnet on the dynamic behavior of the system is analyzed.(5) The dynamic equation of the longitudinal auxiliary magnetic bistable piezoelectric cantilever beam considering the nonlinear curvature, the nonlinear inertia term and the nonlinear magnetic force is derived based on Hamilton's principle.Numerical simulation of the dynamic equation is considered, the results analysis the waveform and the phase portraits of the system. The dynamic characteristics of the longitudinal auxiliary magnetic bistable piezoelectric cantilever beam are studied by changing the parameters of the system.