Design, simulation and experiment for a piezoelectric energy harvester based on fluid pressure pulsation in water hydraulic system

Water hydraulic pump is an essential component of water hydraulic system, and periodic pressure pulsation is generated during its operation. A hydraulic piezoelectric energy harvester (HPEH) with excellent sealing and insulation performance is proposed to recover the vibrational energy from pressure pulsation. The energy harvesting performance of HPEH is investigated through simulation and experiment under different parameter combinations. The results show that the transient voltage and transient pressure exhibit the same fundamental and harmonic frequencies. Higher pressure amplitude is favorable for deformation and can lead to higher electric energy generation, but the static pressure has little effect on the energy harvesting performance. Although the voltage increasing with increasing the resistance, the average power increases first and then decreases. Compared with the existing piezoelectric energy harvesters, the present HPEH has advantages in voltage and power density. The root mean square voltage, average power and power density can reach up to 9.9 V, 791.7 μW and 2.067 μW/(bar·mm3), respectively. Moreover, 42 LEDs connected in parallel are lighted to demonstrate the feasibility of using the HPEH as a power source. This study can lay a foundation for driving low-power components using piezoelectric harvesting energy from pressure pulsation in water hydraulic system.