Synchronized Switch Harvesting Technique Applied to Electromagnetic Vibrations Harvester
E. Arroyo, A. Badel, F. FormosaContact : [email protected]
Objectives Model of an electromagnetic generator
Classical extraction circuit
Autonomous sensor node
Mechanical Energy ( Vibrations )
Non usable electrical energy
Usable electrical energy
Mechanical energy inside the gene.
Mech.-to-elec. conversion
Vibrations
Mech.-to-mech. conversion
Ener
gy h
arve
ster
Electrical extraction circuit
- Minimal losses
- Usable DC voltage levels
- Self-supply of the circuit - Large bandwidth
- Highest possible power
Application of non-linear techniques developed for piezoelectric generators to electromagnetic generators
Optimization of the electrical extraction circuit for electromagnetic generators
Comparison with classical extraction technique
Experimentation
PR strongly dependent on the load
Experiments
PSMFE constant from R = 1kΩ
AC voltage level < 0.2V
Usually increased by increasing the number of turns of the coil, at the detriment of the energy density
Usable DC voltage
+ RectifierLow voltage level
From 1 to 30 V
Simplified linear model
P overestimated
T
Charge of C2
Charge of C1
T/2
Commutation at each extremum of current
SMFE circuitModels
Simulations
Performed on a non optimized generator
k²= 0.03%ξe = 1
Resonance frequency : 153 Hz
Charge of C1 or C2
PR:
Harvested power with the classical technique, with matching impedance
PSMFE:
Harvested power with the SMFE technique
Generator parameters:
For low ξe :
Same or more power extracted with the SMFE technique
For high ξe :
Less power extracted with the SMFE technique
Worse case : 10% less
MIC
A 2
(Ber
kele
y)
Best case : 2.5 more power
Only 3 parameters are required to describe the behaviour of an
electromagnetic generator
My Mu Cu Ku I
0LV u r I L I
2m
C
KM
22
0
kKL
0 02L
e
r
L
0 02c
R
L
Top Related