Galloping-Based Piezoelectric Energy Harvesters And Segmented Piezoelectric Optimization Method

With the continuous development of radio technology and micro electro mechanical system,new requirements are put forward for the power supply demand of micro system,because of the small volume of micro system,complex installation environment,traditional power supply means,large volume,high maintenance frequency and cost.So it is one of the problems that need to be solved to find a new way of power supply.Among them,energy harvesters technology emerges as the times require.As a kind of technology,it can collect the waste energy of the outside world and provide the power needed for the operation of low-power electronic components.On the one hand,the technology can reduce the waste caused by battery replacement,so it has the significance of protecting the ecological environment,on the other hand,it can reduce the maintenance and maintenance costs,so it also has economic benefits.Because of these advantages,coupled with the development of low-power electronic components and radio sensing technology,the field of energy harvesters has been widely concerned by academia and industry.In recent years,the most popular research is to use the vibration energy in aeroelastic phenomenon to convert it into available electric energy.The purpose of piezoelectric energy collection on wings or other pneumatic devices is to use the mechanical energy of structural aeroelastic vibration to convert it into usable electrical energy,and supply power for sensors of monitoring pneumatic devices.The core idea of aeroelastic energy harvesters is to transform the mechanical energy of aeroelastic vibration of structure into electrical energy output,so as to realize the effective utilization of aeroelastic phenomenon.From the point of view of energy harvesters,aeroelastic phenomenon is a potential energy source.The combination of the two has certain advantages.The self-excited characteristic of aeroelastic simplifies the design of energy harvesters device.In addition,aeroelastic energy harvesters provides a new way for small-scale wind power generation.The application of energy harvesters technology can effectively reduce the complexity of the structure,improve the reliability of the system,and reduce the maintenance cost and time.The electric energy collected through energy collection has the potential to charge batteries,supply energy for low-power systems,and even realize the self supply of some micro electronic systems.For aeroelastic energy harvesters,because the motion amplitude generated by self-excited vibration is generally large,the self-strain also increases,and the strain joint also increases.For a modal shape,if the charges generated by the two adjacent sides of the strain node gather on the continuous electrode surface,due to the phase difference of strain distribution,they will cancel each other and the electric energy output will be reduced.Therefore,in order to avoid the electrical offset,a new optimization method named piecewise piezoelectric is used to optimize the design of piezoelectric model.In this paper,the galloping energy collection of non-streamline body in aeroelastic energy collection and the analysis of its strain section are mainly studied.Firstly,the electromechanical coupling equation of the galloping energy harvesters is obtained by the Euler Bernoulli beam hypothesis,then the aerodynamic force and aerodynamic moment are obtained based on the quasi steady hypothesis,and the distributed parameter model of the energy harvesters is obtained by the Galerkin method.The piezoelectric characteristics are analyzed by modern analytical methods.Then,in order to optimize the segmented electrode for the cantilever of the galloping piezoelectric energy harvester,firstly,the strain analysis is carried out.In the second mode,we find that the larger end mass and the moment of inertia can cause three strain joints on the cantilever beam.Based on a new optimization idea,if no segmented electrode optimization is made,the charges on both sides of the transformer will cancel each other,resulting in electricity.The output of learning is greatly reduced.In the end of this paper,the cantilever piezoelectric energy harvesters is optimized by segment electrode,and the optimized model is compared with the non-optimized model by COMSOL finite element simulation.