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Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
HYATT REGENCYNOVEMBER 13-14, 2008
ISTANBUL
I.Arsie, G.Rizzo, M.SorrentinoDIMEC, University of Salerno, Italy
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Outline
IntroductionHSV: models and resultsOptimization of Management StrategiesThe PrototypeConclusions
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
The background
Serious alarms about global
warming and climate
changes related to CO2
concentration in the
atmosphere
Growing demand for mobility. The Chindia factor, 1/3 of world population. 400% and 205% increase in cars for China and India from 1990 - 2000
CO2 emission for transport is increased in last 30 years both in relative and absolute values. (UK data. Similar trends hold in Western
countries).
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From conferences to cartoons
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Possible Solutions?
Kyoto Protocol: A possible solution to fossil fuel depletion and global warming is an increased recourse to Renewable Energy (RE).Possible application to cars:
Fuels/Energy from RE (Bio-Fuels, H2)
Solar Cars
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UL Solar Energy
1.5 106 km
A very small part of the energy radiated by sun strikes the Earth (a part over two
billions).
Nuclear fusion into the sun produces an enormous amount of
energy, irradiated into the space.
Solar energy is partly reflected to the space (15%), partly used to evaporate water (30%)
and partly absorbed by plants, oceans and land, and for men use (55%).
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Solar Energy vs. Energy Consumption
The solar energy striking the US in one day is almost equivalent to the energy consumption for one
and a half year
= +
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UL PV Panels
Much of today's research in multi-junction cells focuses on gallium arsenide as one of the component cells. Such cells have reached efficiencies of around 40% under concentrated sunlight (Fresnel lens).
Today's most common PV devices use a single-junction with poli-crystalline silicon, with efficiency of about 12%
Use of mono-crystalline silicon results in higher efficiency (15% and more)
Multi-junction cell
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
PV efficiency trends
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Solar Panels Production and Prices
The production of photovoltaic panels has remarkably increased
since 90’s in terms of installed power.
Their cost, after a continuous decrease and an inversion of the trend occurred in 2004, appears now quite stable
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Outline
IntroductionHSV: models and resultsOptimization of Management StrategiesThe PrototypeConclusions
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Solar Cars
Various propotypes of solar cars have been developed, for
racing and demonstrative use
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Solar Cars do not represent realistic alternative to “normal” cars, due to:
Limited power and performance.Limited range.Discontinuous energy source.High cost.
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Hybrid Electric Vehicles
Honda Insight
Toyota Prius
Ford EscapeGM Precept
F.Porsche, 1900Buick Skylark, 1974
Peugeot 308 Hybrid-
Diesel
Mercedes S400 Hybrid-
Diesel
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HEV and PV: a possible marriage?
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About the dowry
Conventional/Hybrid car
PV panels
Energy 600 KWh 50 kg gasoline tank
<50 KWh/day6 m2 @ 8.5KWh/m2/day
Power 100 KW < 1 KW
Q: Is solar energy a rich dowry for a vehicle?
Solar Cars: lighter than CarsHEVs: heavier than Cars
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Energy Balance in a Solar Car
sun
dsunPVp
sun
dsunsunPVpdpsun h
heA
h
hheAEEE
Net solar energy available to propulsion [KWh/day]
esun=average insolation (KWh/m2day)APV=effective panel area = APV,H+0.5 APV,V
PV=panel efficiency (=0.13): reduction factor due to charge/discharge processes in battery (=0.9): insulation reduction during driving, due to shadow (=0.9)
Daily time fraction spent in parking mode
Daily time fraction spent in driving modeParking mode Driving mode
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
0 5 10 150
20
40
60
80
100
Car Average Power [KW]
Sol
ar E
nerg
y %
APVH[m2]=6 APV
V[m2]=0 Vol.[m3]=8.8997
h=1h=2h=3h=5h=10
Solar Fraction
Site: San Antonio, TexasYearly Averaged Data
Continuous use (h=10) with 100% recourse to the sun can be achieved only at very low
power (<1 KW).
Solar energy can represent a significant contribution for
intermittent use (h=1-2) and for limited average power.
For average power from 5 to 10 KW and driving hours from 1 to
2, solar contribution ranges from 18% to 60%.
6 m2@12% or 3 m2@24%
Driving
hours
per
day
Are these values of power and driving hours significant?
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Statistics on Car Drivers
about 71% of UK users reaches their office by car46% of them have trips shorter than 20 min mostly with only one person on board.
Source: Labour Force Survey, http://www.statistics.gov.uk/CCI/nscl.asp?ID=8027
Some recent studies of the UK government stated that
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Power Demand
0 200 400 600 800 1000 12000
50
100
150Speed [km/h]
0 200 400 600 800 1000 1200-40
-20
0
20
40
60
Time [s]
Power [KW]
Power demand can be determined integrating the
longitudinal vehicle model over a mission
cycle.
During urban drive, limited average
power can be required to drive a
small car.
Urban Extra-urban
Mass=1000 Kg - Length=3.75 m
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0
500
1000
1500
2000
2500
3000
0 20 40 60 80
2 axis tracking1 axis trackingTilt=LatitudeHorizontalVertical (mean)
Latitude (deg)
Average Yearly Energy (KWh/year)
Almost a factor 2 between maximum and minimum latitudes.
For fixed panels, there is not a relevant loss by adopting horizontal position with respect to “optimal” tilt, particularly at low latitudes.
Negligible differences between 2-axis and 1-axis tracking systems.
Energy absorbed with vertical position is significantly lower, mainly at low latitudes.
46%
79%
Adoption of moving solar roof for parking phases can significantly increase solar energy, particolarly at the high latitudes
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UL Some HSV prototypes
Solar Toyota PriusBy Steve Lapp
Ultra-CommuterThe University of Queensland
Viking 23Western Washington University Tokyo University of Agriculture
and Technology
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Solar Prius
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It is estimated that the PV Prius will consume somewhere between 17% and 29% less gasoline than the stock Prius (range per day: 5-8 miles)
Prius with an aftermarket 215 W monocristalline solar module with peak power tracking and a 95%
efficiency DC-DC Converter
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Well to Wheel
H2
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
HSV vs HEV
HEV ≠ Conventional Car + Electric Motor
HSV ≠ HEV + PV
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
HSV vs HEV
Mission profile (HSV should be optimized for urban driving)Different SOC management strategies.Different structure (vehicle dimension, hybrid architecture)
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Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
HSV vs HEV controlSOC
Time
driving pathIn most HEVs, a charge sustaining strategy is
adopted: the battery State Of Charge (SOC) is unchanged
within a driving path.
ΔSOC
SOC
Time
driving path parking
dayA suitable strategy for HSV instead can restore the initial
SOC within a whole day, considering battery charging
during parking time.
Charge depletion
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Potential advantages of Series HSVNo mechanical link between generator and wheels:
Very effective vibration insulation can be achievedLess constraints for vehicle layoutPossible use of in-wheel motors with advanced traction control techniques
Engines optimized for steady operation can be used:
ICE designed and optimized for steady conditionsD.I. Stratified charge engine (4 or 2 strokes)Micro gas turbine
Series architecture acts as a bridge towards the introduction of fuel cell powertrains.More suitable for V2G applications
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Vehicle to Grid (V2G)V2G concept: to connect parked electric driven vehicles (electric, hybrid, hybrid solar, fuel-cell) to the grid by a two-way computer controlled hook up.The power capacity of the automotive fleet is about 10 times greater than the electrical generating plants (in US) and is idle over the 95%.
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Advantages:Reduction of costs for peak power production.Toward the distributed generation, with reduction of Transmission and Distribution (T&D) costs.Facilitate integration of intermittent renewable resources.The value of the utility exceeds the costs for the two-way hook up and for the reduced vehicle battery life.
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
V2G: Additional advantages for HSV
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Possible use of moto-generator as cogenerator
for domestic use
Possibility to transfer excess solar power
to the grid
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Engine control in a series HSV
ICE Efficiency
A BICEP
optP MAXP
ICE Power
In a series HSV, the Internal Combustion Engine could operate on the optimum
efficiency curve and whenever possible at its maximum efficiency
Part load operation can be avoided and substituted by intermittent operation at
maximum efficiency
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ICE EG
PV Panels
EM
Parking
with sunlight
Battery
VMU
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ICE EG
PV Panels
EM
Hybrid
with sunlight
Battery
VMU
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ICE EG
PV Panels
EM
Electric Driving
with sunlight
Battery
VMU
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ICE EG
Battery
PV Panels
EM
Regenerative Braking
with sunlight
VMU
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ICE EG
Battery
PV Panels
EM
Recharge from grid
with sunlight
VMU
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ICE EG
Battery
PV Panels
EM
Power to grid (V2G)
with sunlight
VMU
Thermal load
heat
“We believe that the most plausible vehicle of the future is a plug-in hybrid...”
(Center for Energy and Climate Solutions, 2004)
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OUTPUTCar Stability – Fuel Savings – Weight - Payback
Objective Function and Constraints
MODELSEnergy Flows for HSV/CC – Car sizing - Weight - Cost
DESIGN VARIABLESPV Panel Area and Position
– EG and EM Power – Car dimensions – Materials
DESIGN SPECIFICATIONPower demand – Insolation –
HSV Structure
EXHOGENOUS VARIABLESFuel Price – Panel
Efficiency – Unit weight and costs
CONTROL VARIABLESControl Strategy for
EG – MPPT for PV
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Payback Optimization
Objective Function: minimum Payback XPBXmin
Gi NiXG ,10
Design variables X:
1. Electric Generator Power PEG2. Electric Motor Power PEM3. Horizontal panel area APV,H4. Vertical panel area APV,V5. Car length l6. Car width w7. Car Height h8. Weight reduction factor of car chassis with respect to base value CWf
Inequality Constraints
Solved by Sequential Quadratic Programming (Matlab routine FMINCON)
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Power to Weight ratio equal to the conventional vehicle1
CV
HSV
PtW
PtW
maxmin
maxmin
maxmin
hhh
www
lll
Car dimensions within assigned limits, obtained by the database of commercial vehicles
maxmin
maxmin
w
h
w
h
w
h
w
l
w
l
w
lLength to width ratio and height to width ratio within assigned limits, obtained by the database of commercial vehicles
hwlAA
wlAA
VPVVPV
HPVHPV
,,
,
max,,
max,,
PV panels area compatible with car dimensions, according to the given geometrical model
EG Power within lower and upper boundsmax.min, EGEGEG PPP
7.0CWf Car weight reduction factor not lower than 0.7
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
#cf
€/kgcPV
€/m2 €/W P [/] APV,H [m
2] PEG [kW] PB [yrs]
1 1.77 800/6.15 0.13 0 35.5 6.1
2 1.77 800/6.15 0.13 3 35.5 9.9
3 1.77 200/2.15 0.13 4 37 5.6
4 3.54 200/2.15 0.16 5.6 38.4 2.4
A very good payback (2.4 years) is by doubling fuel cost, reducing by 4 panel cost,
and considering 16% panel efficiency
Optimal design results
Fuel Price ≈ 2.1 €/KGItaly, June, 2008
PV Retail Price:June 2008: 4.70 €/W
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0 5 10 15 20 25 30 35 40 45 500
50
100
150
200
250
300
0 5 10 15 20 25 30 35 40 45 500
20
40
60
80
100
120
Power vs. voltage characteristic of a PV field
Uniform working conditions
Mismatched PV field
Due to changing sun irradiance, PV source must be matched to the load to draw maximum power.Maximum Power Point Tracking (MPPT) techniques are adopted.The presence of local maxima occur during mismatched conditions, due to shading effects and temperature variations in different parts of the panel.The characteristic may change rapidly during driving conditions, required advanced MPPT control.
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Sources of mismatchingDifferent solar irradiation levels due to:
CloudsShadowsDifferent orientation of parts of the PV fieldDirtinessTolerances (due to manufacturing and/or ageing)
Different types of panels (different models, photo-glass, coloured) in the same string
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
MPPT management of PV arrayMPPT strategy are implemented to maximizing PV efficiency throughout the day.
P
Vi
MPPT
Vi
• Power given to the battery
• Max Allowable Power
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Outline
IntroductionHSV: models and resultsOptimization of Management StrategiesThe PrototypeConclusions
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
HSV Modeling
Longitudinal model of the HSV protoype:
vdt
dvMvACCvgMP effxrHSVw 35.0sincos Power at wheels
EM Power
0/ wPVDCACEGEMB PifPPPP
0
0
0
/
wEMtrwEM
wPVBDCACEGEMEM
wtr
wEM
PifPP
PifPPPP
PifP
P
Battery recharge power
= experimentally characterized
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Experimental characterization: EG and EM
The electric generator was characterized connecting a pure resistive electrical load.A 4° order polynomial regression was obtained.
0 1 2 3 4 5 60
0.05
0.1
0.15
0.2
0.25
0.3
0.35
Power [KVA]
EG
[/]
Experimental
Simulated
EM efficiency is modeled by a 3rd order polynomial regression identified vs. manufacturer technical data.
0 2 4 6 8 10 12 140.65
0.7
0.75
0.8
0.85
0.9
Power [KW]
EM
[/]
experimental
simulated
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Experimental characterization: the Battery pack
Battery is modeled applying the Kirchoff law to an equivalent circuit.
The internal resistance was modeled as a nonlinear function of state of charge.
Model accuracy was checked against experiments.
Rin
__E0
Vr
Vbatt
E0= battery open circuit voltage
Idis= discharging current
Vr= internal voltage losses
Rin
__E0
Vr
Vbatt
Rin= battery internal resistance
Vbatt= effective voltage
Ichg= charging current
Idis Ichg
a) b)
0 20 40 60 80 1005.8
6
6.2
6.4
Current [A]
Battery voltage [V] in discharge operation mode (a)
ExperimentalBattery Model
0 20 40 60 80 1006.2
6.4
6.6
6.8
7
7.2
Current [A]
Battery voltage [V] in charge operation mode (b)
ExperimentalBattery Model 0 0.2 0.4 0.6 0.8 1
0.005
0.01
0.015
0.02
0.025
State of charge [/]
Battery internal resistance [Ohm]
DischargeCharge
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Experimental characterization: the PV array
The PV array has been characterized by connecting the converter output to a resistive load.
0 5 10 15 20 25 30 35 40 450
10
20
30
40
50
60
PV Voltage [ V ]
PV
Pow
er [W
]
experimentalsimulated
Daily Average Energy [kWh/kWp/day]
0
1
2
3
4
5
6
PV = 10 %(390 W/m2 irradiation)
The average PV daily energy was derived from an experimental year-thorough distribution:
dayWhA
EE
daykWp
kWhE
PVdaysunPV
daysun
/45010
44.11.3
10
1.3
,
,
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
ICE thermal transients
K
t
ssinss eTTTtT
Engine temperature dynamics is estimated by a first order dynamic model
60027OFF
15082ON
K [s]Tss [°C]ICE operation
Steady state temperatures and time constants are assigned
for ICE on and ICE off events0 1000 2000 3000 4000 5000
20
30
40
50
60
70
80
90
Time [s]
T [°
C]
Engine temperature
N = 1N = 4
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Thermal effects on power and SFC
ss
engss T
TfPtP
ss
eng
ss
T
Tf
PSFCtSFC
Specific Fuel Consumption and power are related to the ratio
between actual temperature and its steady state value, starting from experimental data for a SI
engine
3
21
ss
eng
T
T
ef
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Modeling of HC emissionsDue to the ICE intermittent use, HC emissions occurring during warm-up have to be accounted for.
0 50 100 150 200 250 300 350 400 45020
30
40
50
60
70
80
Time [s]
Engine Temp. [°C]
0 50 100 150 200 250 300 350 400 4500
200
400
600
800
1000
Time [s]
HC [ppm]
Experimental warm-up HC dynamics
]20:..] s:
engTbatHC
0 5 10 15 200
200
400
600
800
Time [s]
HC [ppm]
Tin
= 26 °C
Tin
= 55 °C
K
t
ssinss eHCHCHCtHC
[0-20] s: HC formation mechanism modeled as a first order process
in
inin TTHC
1
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Day through charge sustaining is achieved constraining SOC variations.
Energy management strategy
dtXm HSVfX ,min
minSOCSOC
maxSOCSOC
Minimum and maximum values considered for state of charge
Power
Time
Traction power ICE Power
In case of ICE intermittent use, energy management for HSV can be addressed via an optimization analysis.
The decision variables X include number of ICE starts, starting time, duration and ICE power level.
00 pfday SOCSOCSOCSOC
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Simulation of HSV prototype: scenario analysis
0 2 4 6 8 10 120
5
10
15
20
25
30
35
Time [min]
Vehicle speed [km/h]
The prototype was simulated on a driving cycle composed of 4 ECE-like modules.
ICE power [kW] 46
Fuel gasoline
PEG [kW] 43
PEM [kW] 90
Number of battery modules [/] 27
PV horizontal surface APV,H [m2] 1.44
Coefficient of drag (Cd) 0.4
Frontal area [m2] 2.6
Weight [kg] 1465
HSV Specification
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
0 1000 2000 3000 4000 500020
30
40
50
60
70
80
90
Time [s]
Engine temperature [°C]
N = 2N = 4N =8
0 1000 2000 3000 4000 5000-40
-20
0
20
40
60
Time [s]
HSV power [kW]
Traction powerEG
N2
EGN4
1 2 3 4 5 6 7 80
5
10
15
20
N. of starts
Fuel economy improvement [%]
Control optimization results (DBM) 1/3
• Initially fuel economy increases with engine starts due to the higher degrees of freedom.
• After 4 ICE-on, fuel economy tends to decrease due to the increasing impact of thermal transients.
engTN
PEG,N4 > PEG,N2
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
• HC emissions show an increasing trend with number of starts.
• A local minimum occurs at N =4.
• Such a behavior is due to the different temperature trajectories.
1 2 3 4 5 6 7 80
0.5
1
1.5
2
N. of starts
HC [grams]
0 1000 2000 3000 4000 500020
30
40
50
60
70
80
90
Time [s]
Engine temperature [°C]
N = 2N = 4N =8
0 1000 2000 3000 4000 500020
30
40
50
60
70
80
90
Time [s]
Engine temperature [K]
N = 3N = 4
0 1000 2000 3000 4000 50000
10
20
30
40
Time [s]
HC emissions [g/h]
N = 3N = 4
Control optimization results (DBM) 2/3
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Control optimization results (DBM) 3/3
0 1000 2000 3000 4000 5000-30-15
015304560
Time [s]
HSV power [kW] - N = 4 (a)
drivegen
0 1000 2000 3000 4000 50000.65
0.7
0.75
0.8
Time [s]
State of charge [/] N = 4 - (b)• SOC excursions
are satisfactorily bounded
• Final SOC leaves room for PV charging during parking phases
• On average EG operating conditions fall in a high efficiency region.
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Energy management optimization by means of genetic algorithm (GA) search
Binary representation of the optimization problem
As both integer and real variables are involved, the GA search method was selected for such an analysis.HC emissions and fuel consumption for cranking energy have been also included in the objective function.
GA parameters
Population size 70
Number of generations 100
Crossover probability 0.8
Mutation probability 0.033
Decision variable
Definition range
PrecisionNumber of bits
NEG [1 8] 1 3
tEG (min) [0 78/ NEG] 0.073/ NEG 10
tEG (min) [0 78/ NEG] 0.073/ NEG 10
PEG (kW) [0 43] 0.040 10
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Control optimization results (GA) 1/2
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0 10 20 30 40 50 60 70 80-40
-20
0
20
40
60
80
Time [min]
EG and battery power trajectories [kW]
EG
Battery
0 10 20 30 40 50 60 70 8020
30
40
50
60
70
80
90
Time [min]
Engine temperature [°C]
DBM
GA
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Control optimization results (GA) 2/2
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0 10 20 30 40 50 60 70 80-50
-25
0
25
50
Time [min]
Power at wheels [kW]
0 10 20 30 40 50 60 70 800.4
0.6
0.8
1
Time [min]
SOC variation [/] To be recovered in the parking phase
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Comparison between GA and DBM results
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Optimization outputs DBM GA 1
NEG 4 3
Fuel consumption [kg] and % saving (*)
2.41 (14.8%)
2.48 (12.4%)
HC emissions 1 (g) 1.13 0.85
Average engine temperature [°C] 65 68
Max SOC [/] 0.79 0.88
Min SOC [/] 0.65 0.58
HC emissions 2 (g/km) 0.025 0.018
A further optimization analysis was run considering an increase in PV horizontal area from 1.44 m2 to 3 m2. Such configuration upgrade results in a fuel consumption reduction
from 2.48 kg to 2.28 kg (19.4% saving).
(*) conventional vehicle fuel consumption = 2.83 Kg
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Outline
IntroductionHSV: models and resultsOptimization of Management StrategiesThe PrototypeConclusions
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
HSV PrototypeVehicle Piaggio Porter
Length 3.370 m
Width 1.395 m
Height 1.870 m
Drive ratio 1:4.875
Electric Motor BRUSA MV 200 – 84 V
Continuous Power 9 KW
Peak Power 15 KW
Batteries 16 6V Modules Pb-Gel
Mass 520 Kg
Capacity 180 Ah
Photovoltaic Panels Polycrystalline
Surface 1.44 m2
Weight 60 kg
Efficiency 0.13
Electric Generator Diesel Yanmar S 6000
Power COP/LTP 5.67/6.92 kVA
Specific fuel cons. 272 g/kWh
Weight 120 kg
Overall weight (with driver)
Weight 1950 kg
A prototype of hybrid solar vehicle with series structure has been developed at the University of Salerno, within the EU Leonardo Program “Energy Conversion
Systems and Their Environmental Impact” (www.dimec.unisa.it/leonardo)
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http://www.dimec.unisa.it/leonardoSponsored by ACS, Salerno (I), Lombardini (I), Saggese (I).
Leonardo Program (I05/B/P/PP-154181)Energy Conversion Systems and Their Environmental Impact
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www.dimec.unisa.it/LeonardoA multi-lingual web site has been developed.
The site has more than 1000 visits per week
and is at the top positions on Google.
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
Participation to the FIA Alternative Energies Cup race ECO-TARGA FLORIO (Palermo, Italy)
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IntroductionHSV: models and resultsOptimization of Management StrategiesThe PrototypeConclusions
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ConclusionsHybrid Solar Vehicles can represent a valuable solution for energy saving and environmental issues, but accurate re-design and optimization of both vehicle and powertrain with respect to HEV are required.Economic feasibility could be achieved in a near future, with realistic assumptions for component costs, fuel price and PV panel efficiency.Significant fuel savings can be obtained by proper ICE management strategies. Thermal transient effects on fuel consumption and HC emissions must be considered in case of intermittent use.The use of optimization techniques (GA, DBM) has allowed to select the best management strategies, to be used as benchmark for real-time implementable control.Interdisciplinary research is needed, but also a systematic dissemination of results and potentialities, in order to remove the obstacles to the diffusion of such vehicles.
Hybrid Solar Vehicles: Perspectives, Problems, Management Strategies
On-going activities
Development and implementation of real-time control strategies and comparison with benchmark solutions.
On road tests on the prototype to validate both simulation results and control strategies.
Installation of an automated sun-tracking roof to further enhance solar energy contribution.
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Thank you for your kind attention