Research On Electromagnetic Energy Collection Device Based On Closed Magnetic Circuit

With the development of microelectronics and MEMS,a large number of sensors with small size,long life and low power consumption are widely used in wireless sensor networks and the Internet of Things to realize environmental monitoring,health monitoring and car tire pressure monitoring etc.However,energy supply has become one of the major bottlenecks restricting the popularization and application of sensor nodes.At present,the most common power supply method for wireless sensor nodes is using chemical batteries.However,batteries have many problems such as short lifetimes,certain pollution to the environment,need to be replaced regularly.A viable alternative is to use self-contained energy,which is to use energy harvesting technology to capture energy in the sensor node environment.Combining the current electromagnetic energy collection device with low power generation efficiency and complex devices,two electromagnetic energy collection devices were designed.One is a shoe electromagnetic energy collection device,and the other is a cantilever vibration energy collection device.Through simulation We can know the influence of parameters on power generation efficiency and get the best parameters value that maximize power generation efficiency.through the simulation,we can calculate the optimized voltage and compare it with the voltage before optimization.The work I did was as follows:1.The footwear electromagnetic energy collection device is used Faraday's law of electromagnetic induction.It can cut and restore magnetic paths through clever design.The left and right arc arms are made of magnetic material and elastic material,so they can not only bend to produce recoverable deformation but also spread magnetic.We use Ansoft Maxwell software for static simulation to get the best parameters of the structure,then through the dynamic simulation,we know the optimized output power of the device is 643 mW,and the energy collection efficiency of the device is greatly improved by optimizing.It can supply power to most low-power wireless sensor devices.2.The cantilever beam vibration energy harvesting device is a new type of swing structure.The innovation of the device lies in the fact that the yoke plate is fixed on both sides of the cantilever beam,and movement of the yoke plate can changes the magnetic path.This design can reduce the cost of the device,enable a wider range of energy harvesting,and achieve higher efficiency.At the same time,a mass is placed on the top of the cantilever beam to increase the vibration amplitude of the cantilever beam and improve the power generation efficiency.We use Ansoft Maxwell software for static simulation to get the best parameters of the structure,then through the dynamic simulation,we know the optimized output power of the device is 1629 mW,and the energy collection efficiency of the device is greatly improved by optimizing.It can supply power to most low-power wireless sensor devices.