A Noncontact Magneto–Piezo Harvester-Based Vehicle Regenerative Suspension System: An Experimental Study

Recent research has examined the possibility of recovering energy from mechanical vibration induced by a vehicle shock absorber using piezoelectric and electromagnetic transducers. In terms of automotive applications, piezoelectric vibration energy harvesting shows promise for recapturing some (even if small) amounts of vehicle vibration energy, which would otherwise be wasted through the vehicle dampers. Functional materials, such as piezoelectric materials, are capable of converting mechanical energy into useful electrical energy and vice versa. In this paper, an innovative rotational piezoelectric vibration-energy-harvesting device is presented that employs a magnetic coupling mechanism and provides robust performance over a range of frequencies. The piezoelectric energy harvester is driven by a unidirectional suspension system. An experimental investigation was carried out to study the performance of the manufactured prototype. We observed no damage to the prototype after operating continuously at a vibration amplitude of 5 mm at a frequency of 2.5 Hz for over 10,000 cycles. In addition, the presented regenerative suspension system is capable of producing high and relatively steady open-circuit voltages, irrespective of excitation frequencies. The results demonstrate that regenerative shock absorber is robust and has a broad frequency range.