<p>An
elliptically
shaped
electromagnetic
vibration
energy
harvester
is
presented
for
two-
and
one-dimensional
motions
with
the
easy
tuning
of
resonance
frequency.
The
consists
a
free-to-move
ring-shaped
permanent
magnet
radial
magnetization,
set
cube
magnets
distributed
in
fixed
holder,
two
coil
windings
located
above
below
harvester.
When
device
exposed
to
vibrations,
ring
moves
until
magnetic
restoring
force
from
pushes
it
back
while
inducing
an
on
coils.
performance
characterized
using
XY-shaker,
whose
frequency
swept
1
Hz
10
motion
amplitudes
2
mm
4
both
axes
simultaneously.
Unlike
1-D
harvesters,
resulting
output
power
shows
resonant
frequencies
at
4.5
7
Hz,
which
can
generate
around
1.5
mW.
also
displays
nonlinear
hardening
resonator
behaviour.
Finally,
1D
experimental
results
show
that
prototype
depends
its
angular
position
respect
direction
source,
reaching
maximum
45
degree.</p>
Sensors and Actuators A Physical,
Journal Year:
2022,
Volume and Issue:
350, P. 114091 - 114091
Published: Dec. 15, 2022
An
elliptically
shaped
electromagnetic
vibration
energy
harvester
is
presented
for
two-
and
one-dimensional
motions
with
the
easy
tuning
of
resonance
frequency.
The
consists
a
free-to-move
ring-shaped
permanent
magnet
radial
magnetization,
set
cube
magnets
distributed
in
fixed
holder,
two
coil
windings
located
above
below
harvester.
When
device
exposed
to
vibrations,
ring
moves
until
magnetic
restoring
force
from
pushes
it
back
while
inducing
an
on
coils.
performance
characterized
using
XY-shaker,
whose
frequency
swept
1
Hz
10
motion
amplitudes
2
mm
4
both
axes
simultaneously.
Unlike
1-D
harvesters,
resulting
output
power
shows
resonant
frequencies
at
4.5
7
Hz,
which
can
generate
around
1.5
mW.
also
displays
nonlinear
hardening
resonator
behaviour.
Finally,
1D
experimental
results
show
that
prototype
depends
its
angular
position
respect
direction
source,
reaching
maximum
45∘.
Micromachines,
Journal Year:
2023,
Volume and Issue:
14(7), P. 1374 - 1374
Published: July 4, 2023
This
paper
presents
an
improved
solution
for
the
airflow
energy
harvester
based
on
push–pull
diamagnetic
levitation
structure.
A
four-notch
rotor
is
adopted
to
eliminate
offset
of
floating
and
substantially
increase
conversion
rate.
The
new
a
centrally
symmetrical-shaped
magnet,
which
ensures
that
it
not
subjected
cyclically
varying
unbalanced
radial
forces,
thus
avoiding
rotor’s
offset.
Considering
output
voltage
power
several
types
rotors,
was
found
be
optimal.
Furthermore,
with
rotor,
overall
average
in
axial
magnetic
spring
stiffness
9.666%
maximum
monostable
space
1.67%,
but
horizontal
recovery
force
reduced
by
3.97%.
experimental
results
show
at
rate
3000
sccm,
peak
rotation
speed
are
2.709
V
21,367
rpm,
respectively,
40.80%
5.99%
higher
compared
three-notch
rotor.
were
consistent
analytical
simulation.
Based
improvement,
factor
increased
0.127
mV/rpm,
138.47
mW
58.14%,
while
trend
characteristics
also
matched
simulation
results.
In
summary,
proposed
this
significantly
improves
performance
harvester.
Smart Materials and Structures,
Journal Year:
2024,
Volume and Issue:
33(10), P. 105020 - 105020
Published: Sept. 3, 2024
Abstract
With
the
continuous
advancement
of
ultra-low-power
electronic
devices,
capturing
energy
from
surrounding
environment
to
power
these
smart
devices
has
emerged
as
a
new
direction.
However,
most
mechanical
available
for
harvesting
in
exhibits
ultra-low
frequencies.
Therefore,
feasibility
self-powering
low-power
largely
depends
on
effective
utilization
this
ultra-low-frequency
energy.
Consequently,
work
proposes
an
enhanced
electromagnetic
harvester
based
dual
ratchet
structure
with
secondary
recovery.
It
converts
frequency
vibrations
into
fast
rotational
movements
by
means
rack
and
pinion
mechanism,
thus
achieving
high
output
while
maintaining
simple
structure.
Experimental
tests
demonstrate
that
proposed
excellent
under
external
excitation.
Under
excitation
1.5
Hz
amplitude
22
mm,
optimal
load
matched
at
20
Ω,
maximum
reaches
598
mW,
density
1572.65
μ
W
cm
−3
.
The
recovery
accounts
34.4%,
resulting
52.56%
enhancement
harvester’s
performance.
Additionally,
hand-cranking
indicate
fabricated
prototype
can
some
common
including
smartphones,
showcasing
significant
application
potential.
Engineering Research Express,
Journal Year:
2024,
Volume and Issue:
6(4), P. 045342 - 045342
Published: Nov. 8, 2024
Abstract
With
the
rapid
development
of
rail
transit
system,
it
is
becoming
more
demanding
for
structural
health
monitoring
(SHM)
train.
It
crucial
to
supply
power
sensing
devices
on
freight
wagon
ensure
safe
operation
systems.
Three-mode
nonlinear
hybrid
piezoelectric-electromagnetic
vibration
energy
harvester
(TNHVEH)
with
a
three-layer
pickup
system
has
been
designed
and
applied
efficiently
harvest
axle
box
wagons
providing
sensors
online
SHM.
Dynamic
coupling
model
vehicle-harvester
built
devote
relationship
between
bandwidth
degree
TNHVEH
broadening
frequency
band.
Simulation
experimental
results
demonstrate
that
resonant
frequencies
three
systems
are
concentrated
around
27,
70,
120
Hz,
matching
representative
vibrations.
A
maximum
output
voltage
2.97
V
29.4
μW
under
an
optimal
load
300
kΩ
at
0.5
g
acceleration
achieved.
successfully
lights
up
53
LEDs
‘ECJTU’
patterns,
solution
problem
microelectronic
wagons.
