Design of Power Management Circuit for Track Vibration Energy Harvester
摘要
In recent years, harvesting energy from environmental vibrations to power wireless sensor nodes has become a research hotspot. Electromagnetic vibration energy harvesting system has broad application prospects because of its stable structure, high output power and no external power supply. In the electromagnetic vibration energy harvesting system, the power management circuit can efficiently convert and store the electric energy harvested by the energy harvester, which has an important influence on the energy conversion efficiency of the system. However, the current research on electromagnetic vibration energy harvesting systems mainly focuses on energy harvesters, and there is no mature solution for power management circuits. In this study, firstly, two power management circuits PMC-TPS and PMC-RT for electromagnetic vibration energy harvesters are proposed. The circuits include a filter module and a DC-DC conversion module, which can effectively adapt to a variety of electromagnetic vibration energy harvesters and have high energy conversion efficiency. The filter module can convert the fluctuating electric energy output by the vibration energy harvester into a relatively stable electric energy. The DC-DC conversion module can achieve a stable 5 V DC output for subsequent energy storage modules and wireless sensor nodes. Experiments show that the proposed power management circuits can be converted into 5 V DC to charge the energy storage module and supply power to the load for different input voltages, and the energy conversion efficiency can reach up to 92.4%.