Preliminary Study On Magnetic Shape Memoryalloys For Vibration Energy Harvesting

With the continuous development of wireless sensor networks, wireless communicationtechnology and micro-electromechanical systems, micro-energy power systems whichassociated with that are getting people more attention. Mechanical vibration energy iswidespread in nature. Research shows that the vibration energy of the nature can be convertedinto electrical energy using the inverse effect of MSMA, and supply power for wireless sensornetworks and micro electromechanical system. Therefore, this paper studies the vibrationenergy harvester based on magnetically controlled shape memory alloy and powermanagement circuit, the main achievements are as follows.First, the principles of vibration energy harvesting based on MSMA are analyzed,vibration energy harvester is designed based on the feasibility induced voltage produced bythe interaction of outside force and magnetic field through MSMA test system research. Therationality of involved structures is simulated through the finite element analysis software,and the mathematic relation of vibration motor input stress and the output voltage is given.Secondly, in order to improve the capacity of vibration energy storage and the storageefficiency of power management circuits, and provides the power to the load. Vibrationenergy harvesting power management circuits is studied in this paper, and a flybacktransformer power supply management circuit is put forward, then supply power for wirelesssensor networks and micro electromechanical system is realized. The AC/DC rectifier circuit,super capacitor energy storage circuit, control circuit, a pulse signal generating circuit,instantaneous release of energy circuit and voltage regulator circuit are designed andsimulated.Thirdly, energy harvesting based on DC/DC power management circuit insteading offlyback transformer is designed in order to overcome the electromagnetic interferencegenerated by the transformer, the intermittent power supply is realized. Simulation resultsverify the stability of the circuit output voltage, while the design of the power factoradjustment based on power management circuit can supply sustained and stable power to theload.Finally, energy harvesting based on LTC3108power management circuit is proposed,continuous power supply to the load is realized. The inner structure and function of each partof LTC3108are analyzed, and the power management circuit based on LTC3108is designed and simulated. It is proved that the system with a good stability that could output a stablefixed value of direct current in case of fluctuant input of amplitude and frequency, affordcontinuous and stable power for wireless sensor network system, and satisfy the demand forstorage capacity and storage efficiency of vibration energy. At last achievements aresummarized in this paper and the outlook for the future research work is indicated.