화학공학소재연구정보센터
International Journal of Energy Research, Vol.42, No.4, 1702-1713, 2018
Vibration energy harvesting in vehicles by gear segmentation and a virtual displacement filtering algorithm
In this study, vibration straight-line displacements occurring during electric vehicle operations are changed into reversely rotating displacements and divided into small segments by a gear unit. Piezoelectric bending elements are used to form a cantilever beam-based energy feedback mechanism for converting vibration energy into electrical power within an allowable displacement range. A virtual vibration displacement filtering algorithm is proposed to effectively filter virtual displacements that cannot excite the energy harvester and generate electrical power. The average speed of the gear exciting the bender has an accuracy 30%, which is increased using this algorithm compared with 2 other algorithms and directly affects the accuracy of calculating the average power generated by the calculation of piezoelectric bending elements. Theoretical and experimental analyses are conducted for the impact of gear pitch on the regeneration power value by changing the gear pitch at a fixed driving speed. Experiments show that when a vehicle is operated at a fixed speed, the proposed method can be used to obtain the maximum average power of a single piezoelectric bending element through determination of a rational gear pitch. Specifically, when the test vehicle operated at 20 and 60km/h, the gear pitch should have been 7 and 10mm.