Research On Electric Energy Collection And Storage Circuits Of Self-biased Dielectrc Elastomer Generator

Dielectric elastomer has the characteristics of large energy density and low cost,which give it great potential for power generation.Dielectric elastomer generator is suitable for low frequency and large deformation situation,such as wind,ocean.Dielectric elastomer has great research value in the use of renewable energy.The purpose of the self-biased study of dielectric elastomer generator is to get rid of the constraint of external bias power supply and improve the autonomy of the dielectric elastomer generator,and self-biased circuit is a technical means to achieve the aim.In recent studies,self-biased circuits can be divided into the following three categories:power electronic converter,charge pump circuit and integrated self-priming circuit.Among them,the charge pump circuit has the advantages of simple structure,no need of control loop and portability,which make it a research hot spot.A nonlinear electromechanical coupling model of dielectric elastomer generator was established and verified in this paper.The dielectric elastomer generator was equivalent to the spring-mass-damper system,whose second-order differential equation was compared to a second-order differential equation(Kirchhoff s law)of a LRC circuit.Through the above method,the mechanical model was equivalent to the electrical model.By means of the equivalent port,the electrode resistance,the dielectric capacitance and the leakage resistance of DEG were fitted by nonlinear functions respectively.A controlled source in simulation software OrCAD/PSPICE output the mechanical model as input to the equivalent variable capacitance model of the dielectric elastomer generator.An electromechanical coupling model of dielectric elastomer generator was established,whose nonlinear characteristics were studied.The model was the basis for the study of the self-biased dielectric elastomer.The matching between three kinds of self-biased circuits and dielectric elastomer generators was studied by simulation,and a new self-biased circuit was designed.Three kinds of self-biased circuits were simulated and compared.The charge pump circuit was selected as the research object in this paper.Based on the analysis of dielectric elastomer generator generating mechanism,two kinds of self-biased circuits were integrated and a new type of charge pump circuit for dielectric elastomer generator was designed.Under the same conditions,the output voltage of new self-priming circuit was 2.23 times the traditional charge pump circuit through the simulation results.The influences of electromechanical parameters on charge pump circuit were experimentally studied.The range of capacitance ratio and the optimal charge pump capacitance were studied through simulations and experiments.The key parameters of the new self-biased dielectric elastomer generator,the capacitance ratio and the capacitance value of the charge pump,were optimized.Based on the study of electromechanical parameters of dielectric elastomer generator,energy collection and energy storage circuits of self-biased dielectric elastomer generator were built and the reliability test was carried out.Energy conversion efficiency and loss factors of the self-biased dielectric elastomer generator were studied.The test found that multi-stage step-down circuit had reached the expected requirements,so high-voltage energy could be reduced to low-voltage energy and stored to super capacitors.