Research On Broadband Piezoelectric-Electromagnetic Energy Harvester Technology

With the development of micro electronic equipment,it plays an indispensable role in integrated circuit.With the development of low-power technology,the power required by micro-electronic devices is gradually reduced.Along with the development of the 5G,there will be more and more applications of microelectronic devices in the future.At present,the main power supply method for these microelectronic devices is battery power.Whether it is a traditional battery or a new battery,it has its own shortcomings,such as cost High,limited use time,difficult to maintain and replace,easy to cause pollution to the environment,etc.There is a lot of energy in the environment,so obtaining energy from the environment instead of the current battery power supply has become a new research direction in the field of energy science.However,obtaining energy from the environment is subject to many factors,and the vibration energy is less restricted,which is almost everywhere in life.Therefore,obtaining vibration energy has become a common way to obtain environmental energy.In view of the problems of low power,low practicability and narrow applicable frequency band in the traditional single vibration energy harvester mode,this paper provides a broadband piezoelectric electromagnetic composite energy harvester,and performs related simulation,theoretical and experimental research.Firstly,according to the principle of piezoelectric effect and electromagnetic induction,combining with the knowledge of structural mechanics,piezoelectric equation and electromagnetic induction equation,the theoretical model of piezoelectric electromagnetic energy harvester is established.Secondly,finite element simulation analysis is carried out according to the theoretical model,and the simulation software COMSOL is used to establish the piezoelectric energy harvester model.The modal analysis is carried out for the medium voltage part of the theoretical model,and the vibration characteristics and frequency points under different parameters are solved.Then the transient analysis is carried out to find out the changes of voltage and power equivalence under different parameters.At the same time,Maxwell,the electromagnetic analysis software,is used to analyze the electromagnetic part of the theoretical model in transient state first,to find out the peak point of electromagnetic energy harvester,to analyze the static electromagnetic field,to get the output voltage and power of electromagnetic energy harvester under different parameters,and to find out the electromagnetic damping ratio.Then the damping ratio is introduced to simulate the theoretical model,and the output power of the device is obtained.A new structure is designed to widen its working frequency band and simulate its structure.The result shows that it is superior to the traditional structure.Finally,the experimental platform is built,in which the energy harvester experiment is carried out.The piezoelectric energy harvester unit is tested separately,and the experimental data is obtained and compared with the simulation.The electromagnetic energy harvester unit is added to the experiment,and the experimental data is obtained.The composite experiment of piezoelectric energy harvester unit and electromagnetic energy harvester unit is carried out,and the circuit is designed to collect the piezoelectric and electromagnetic energy respectively.The power generation performance after the composite is compared with the data after the former two units separately harvest energy.The experimental results show that the composite energy harvester system is much better than the single unit energy harvester system,and the power generation performance is better than the simple piezoelectric electromagnetic composite energy harvester.