Description: When a piezoceramic trandsucer is stressed mechanically by a force, its electrodes receive a charge that tends
to counteract the imposed strain. This charge may be collected, stored and delivered to power electrical circuits or processors.
The Piezo Bending Generator
When the Energy Harvesting Bender is flexed, one layer is compressed while the other is stretched, resulting in power generation. It may be excited by intermittent pulses or continuously from low frequency to resonant frequency (where rated displacement is achieved at the lowest force level).
The Energy Harvesting Bender is a pre-mounted and pre-wired Double Quick-Mount Bending Generator designed to attach easily to
sources of mechanical strain. Its double ended design lends itself to being mounted either as a cantilever or a simple beam.
Dimensions for the standard -503 size Double Quick-Mounts are shown below.
Piezo Energy Harvesting Circuit
The self powered Piezo Energy Harvesting Circuit collects intermittent or continuous energy input from the piezo generator and efficiently
stores their associated energy in an on-board capacitor bank.
During the charging process, the capacitor voltage is continuously monitored. When it reaches 5.2V the module output is enabled to supply
power to an external (user) load. At this point 55 mJ of energy are available. When generator energy input is high, the output voltage
remains ON continuously. Capacitor voltage is clamped at 6.8V. If external power demand exceeds generation, the output voltage decreases.
When the output voltage drops to 3.1V, power to the load is switched OFF and is not turned on again until the capacitor bank has been
recharged to 5.2V. The circuit accepts input voltages from 0V to ±500V AC or DC and input currents to 400 mA.
Piezo Energy Harvesting Kit
The Energy Harvesting Kit consists of one Double Quick-Mount Harvesting Bender and one Energy Harvesting Circuit.
See an Introduction to Benders Used as Sensor (Generator) Elements.
PIEZO BENDING GENERATOR PERFORMANCE Values to be used as guidelines
Part Number
Weight (grams)
Stiffness (N/m)
Capacitance (nF) Parallel Operation
Rated Tip Deflection (mmpeak)
Rated Frequency (Hz)
Open Circuit Voltage at rated deflection. Parallel Operation (Vpeak)
Closed Circuit Current per sinusoidal cycle, at rated deflection. Parallel Operation
(microApeak/Hz)
Rated Output Power at rated deflection and frequency (mWrms)
EH220-A4-503YB
10.4
188
232
± 2.6
52
± 20.9
± 57
7.1
Bending generator performance is based on the force being applied at the outermost tip of the mount.
Bender & Circuit.
Bender mounted as a cantilever.
Bender mounted as a simple beam.
