Modeling and Analysis of a Hydraulic Energy-Harvesting Shock Absorber

Abstract

This paper proposes a hydraulic energy-harvesting shock absorber prototype, which realizes energy harvesting of the vibration energy dissipated by the automobile suspension system. The structural design of the proposed shock absorber ensures that the unidirectional flow of oil drives the hydraulic motor to generate electricity while obtaining an asymmetrical extension/compression damping force. A mathematical model of the energy-harvesting shock absorber is established, and the simulation results indicate that the damping force can be controlled by varying the load resistance of the feed module, thus adjusting the required damping force ratio of the compression and recovery strokes. By adjusting the external load, the target indicator performance of the shock absorber is achieved while obtaining the required energy recovery power. A series of experiments are conducted on the prototype to verify the validity of the damping characteristics and the energy recovery efficiency as well as to analyze the effect of external load and excitation speed on these characteristics.