Affiliations: [a] Institute of Precision Machinery, Zhejiang Normal
University, Jinhua, Zhejiang, China
Correspondence:
[*]
Corresponding author: Junwu Kan, Institute of Precision
Machinery, Zhejiang Normal University, Jinhua 321004, Zhejiang, China. Tel.:
+86 579 822 865 98; E-mail: jutkjw@163.com
Abstract: To improve energy generating capability and reliability/strength, a
novel piezohydraulic generator for low frequency vibration was presented. The
piezohydraulic generator consisted mainly of a double-rod hydraulic cylinder
for conversion of vibration energy to fluid energy and piezodiscs for
conversion of the fluidic energy to electric energy. A vibration function and
energy-conversion model of the generator was established based on theory of
vibration analysis and simulated to obtain the influence of backpressure on
energy generation as well as optimal frequency. The analysis results show that
both the energy generation and optimal frequency increases with the rising of
backpressure under given other parameters. A piezohydraulic harvester was
fabricated and tested at different backpressure. Both the optimal frequency and
the relative peak voltage/power increase with the rising of backpressure. At
0.2 MPa and 0.8 MPa, the peak-voltage and the relative optimal-frequency are 9
V/11 Hz and 112 V/17.5 Hz respectively. Similarly, the peak-power and the
relative optimal-frequency are 0.58 mW/13 Hz and 11.63 mW/17 Hz respectively.
The research results indicate that a piezohydraulic generator can be used to
harvest energy from a low-frequency and high-level vibration source.
Keywords: Piezoelectric, piezohydraulic, energy harvesting, solid-fluid coupling vibration
