Power generation performance of a bistable speed bump vibration energy harvester

A model of a bistable speed bump vibration energy harvester (BSVEH) is designed by combining the buckling beam, rack and pinion, one-way clutch and speed bump with rotor alternator. One-way clutches are used to ensure the input shaft of rotor alternator to rotate unidirectionally during the up-and-down vibration of the speed bump. The coupled mechanical model of the speed bump energy harvester is established to study the power generation performance subjected to various structural parameters, that is, types of speed bump, types of vehicles, geometrical parameters of the buckling beam, speed increasing ratio and moment of inertia. Simulations show that the output power of the BSVEH (such as 148 J in 1 second) is larger than that of the speed bump energy harvester with linear spring (86 J in 1 second). Compared with the vehicle passing over speed bump energy harvester with linear spring, the vertical and pitch accelerations of a vehicle are decreased 9.3% and 16.5%, respectively when it passes over the BSVEH. Riding quality is also improved. The effect laws of the type and speed of the vehicle speed on the output power of the BSVEH are obtained. The maximum output power of SBVEH is 14.8 W at the vehicle speed 24 km/h. The maximum energy-efficiency of the BSVEH can reach 43.9%. And the maximum average electrical power can arrive at 12.7 W. The optimal parameters favoring the output power of BSVEH are determined. The advantages of power generation and riding quality, correctness of mechanical models and effectiveness of BSVEH are verified by simulation results.