Research On Vibration Energy Harvesting Device Based On Electromagnetic Damping

With the rapid development of science and technology,various outdoor smart devices have been used more and more widely,such as bridge health monitoring systems and high-rise building health monitoring systems,all of which are characterized by high integration and low power consumption.We generally use lithium batteries or solar panels to power these devices.Lithium batteries have the shortcomings of short service life,need to be replaced regularly,and the chemical substances contained in them pollute the environment.Although solar energy can be obtained for free,it is only available in specific locations.It will only exist in large numbers under conditions,so it is of important engineering practical significance to find other clean energy sources to replace lithium batteries and solar energy.The energy in nature is rich and diverse,mainly including solar energy,thermal energy and vibration energy.Because solar energy and thermal energy exist in large quantities only under certain conditions,and vibration energy can be seen everywhere and is continuously stable,it is a good choice to collect vibration energy from the environment to power low-power devices.Aiming at the characteristics and problems of vibration energy recovery,this paper proposes an electromagnetic vibration energy recovery model,and develops a vibration energy recovery device based on electromagnetic damping.The device adopts a moving iron design,and the core part has a simple and practical structure.The vibration energy recovery device based on electromagnetic damping mainly includes a vibrating table and an electromagnetic damper.The function of the vibrating table is to simulate the vibration environment of high-rise buildings,and the electromagnetic damper is used for the functions of vibration energy pickup and energy conversion.Since the voltage signal converted by the device is a non-stationary periodic AC signal,the collected voltage needs to undergo a series of voltage transformations before it can be efficiently used by low-power equipment and energy storage devices.Therefore,the article designs an energy recovery circuit system,which mainly includes 4 parts: impedance matching,full-bridge rectification,step-down voltage stabilization and battery charging management circuit.Experiments show that after the energy collected by the energy recovery device is transformed by the energy recovery circuit system,the output voltage can continuously and stably charge lithium batteries,smart bracelets and mobile phones,and has the ability to supply power to wireless sensor nodes.The main innovations of this article are:1.Different from the traditional vertical vibration energy recovery,the electromagnetic damper vibration device designed in this paper is used to collect the horizontal vibration energy;the use of multiple coils in series connection increases the amplitude of the generated voltage and improves it to a certain extent Energy conversion efficiency.2.The idea of using multiple groups of ring magnets,adjust the length of the magnet group equal to the thickness of a single spiral coil to ensure the symmetrical regularity of the coil output voltage;the magnet group is covered with a magnetic isolation plate to reduce the magnet group The crosstalk between the magnetic lines of induction indirectly increases the magnetic induction intensity.3.Proposed a LTC3388-3 energy recovery circuit,which not only can achieve the function of step-down voltage regulation,consumes little energy,but also has a voltage conversion efficiency of more than 80%;developed a lithium battery charging management circuit scheme under low-power input conditions to achieve battery life Functions such as charge-discharge and over-voltage protection.To sum up: The research work of this article has launched thinking and conception based on the shortcomings of low-power equipment and energy shortage,such as the shortage of energy.The energy recovered by the designed electromagnetic dampingbased vibration energy recovery device can be sustained for low-power devices such as wireless sensors.Stable power supply effectively solves the power supply problem of wireless sensor network system nodes.This provides a new power source for wireless sensors and promotes the further development of wireless sensor technology.