1
New technologies demonstrated at Formula Electric and
Hybrid Italy 2008
Giampiero Brusaglino1, Giuseppe Buja2, Massimiliana Carello3, Antonio Paolo Carlucci4
Christopher H. Onder5 Monica Razzetti6
1 ATA -Associazione Tecnica dell’Automobile, Orbassano (Torino), Italy – giampiero.brusaglino@crf.it
2Università di Padova, Department of Electrical Engineering, Padova, Italy – giuseppe.buja@unipd.it
3Politecnico di Torino, Dipartimento di Meccanica, Torino, Italy – massimiliana.carello@polito.it
4Università del Salento,Facoltà di Ingegneria CREA-Centrro Ricerca Energia e Ambiente, Italy – paolo.carlucci@unile.it
5Swiss Federal Institute of Technology Zurich, Measurement and Control Laboratory – onder@ethz.ch
6ATA – Associazione Tecnica dell’Automobile, Orbassano (Torino), Italy – monica.razzetti@crf.it
EVS-24 International Electric Vehicle Symposium
Stavanger, Norway, May 13th-16th, 2009
Abstract
From 1 to 3 October 2008 the Formula Electric and Hybrid Italy took place in the Safety Testing Center of
Fiat Group Automobiles in Orbassano (TO), Italy.
This fourth edition of Formula EHI, an international competitive demonstration of research outcomes from
university student teams, has brought to the attention of the public and of the industry new technologies and
innovative applications in the area of the systems addressing the ecological mobility. Teams from five
European countries were the protagonists of the event. Several projects, components, systems and concept
have been presented, related to advanced technologies for battery electric, hybrid and fuel cell vehicles.
New technology hybrid, fuel cell and electric vehicles took part to the dynamic test on track for the
evaluation of energy efficiency performance and dynamic behaviour. The 2008 event was a further step of
the editions of Formula TECH held in the previous years and offered a benchmarking overview of the
progress of the technology in the field of electrically propelled vehicles.
Keywords: electric drive, hybrid, scooter, fuel cell
1 Introduction
The development of sustainable technology for
ecological vehicles based on electric propulsion,
can take substantial benefits from the coordinated
efforts in innovation of Academic and Industrial
World.
Results of their actions should be brought to the
public attention, to generate the culture on
ecological vehicles and to stimulate the interest
for their development and diffusion.
Formula Electric and Hybrid Italy is an event
dedicated to the results of student activities in
innovative technologies, which is in line with
these objectives [1].
Meeting Academic Institutions and Industry is a
profitable opportunity to promote the transfer of
research results, to put in evidence further
research needs and to stimulate a cross
fertilisation of initiatives among University
teams.
Formula Electric and Hybrid Italy is addressing
these objectives through a worldwide
participation of University teams, sponsoring
Industries, Research Institutions and Public
Audience.
Students and young engineers are encouraged
and stimulated by this challenging competitive
event to produce their best performance in the
innovation technology for the sustainable future
mobility.
This type of event is a benchmark of the
technology evolution over a variety of vehicle
types and systems and of the relevant trends of
development.
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The annual sequence of the events allows to
progressively update the state of the art for the
various types of ecological mobility means and
systems and to identify the future ways of
development opportunities.
2 The competition structure
The Formula Electric and Hybrid Italy (EHI)is a
competitive event aimed to demonstrate research
results of the Academic world in the field of
ecological technologies, which can contribute to
the establishment of a rational transportation
system addressing the management of the
energy resources and the conservation of
environmental quality.
A part of the goal is to address the industry
attention to new solutions in this field, suitable to
be transferred to the engineering and industrial
development process. Another scope is to
stimulate and activate exchange of information
and contacts among Academic Institutions and
relevant supportive industries about these new
and socially beneficial technologies.
A final aim is to promote and contribute to the
diffusion of the culture of electric and hybrid
vehicles and to encourage industries and users to
the development and the acceptance of these
environment and energy conscious vehicles.
The attention of the Formula EHI and the
evaluation of the merits of the research products
demonstrated by the participants are addressed to
the following aspects:
􀂾 Energy effectiveness in urban mission
􀂾 Dynamic response in practical operation
􀂾 Environmental and utilisation features
􀂾 Innovation level
􀂾 Industrial development potential
The October 2008 event has enriched the frame
of the technologies, which were presented by the
university teams in the previous editions.
Three classes of technology research products
were invited to the competition:
Class 1 – Four wheel car, single seat, formula
style body, equipped with battery electric, hybrid
or fuel cell propulsion systems
Class 2 – Other types of vehicles, including two
or three or four wheel vehicles, without formula
constraints, with the same types of system as
above
Class 3 – Vehicle concepts, systems,
components and projects dealing with electric
and hybrid technologies.
The competition deployment was divided, as in
the previous editions, in static presentation and
dynamic events.
The evaluations were operated by an expert jury
and the scoring was performed according to the
figure of merits related to previously mentioned
aspects
The dynamic events were performed on test
track, according to rules basically consistent with
those of U.S. Formula Hybrid:
- Acceleration (time to reach 75 m on flat
straight line);
- endurance, to test overall performance and
reliability;
- energy consumption.
- autocross, to test handling and
manoeuvrability;
- pursuit test, for a direct competition among
the participants.
Teams of the following Institutions participated
to the event:
- Swiss Federal Institute of Technology
Zurich, with a plug-in hybrid sport car
- Moscow University, with a hybrid
vehicle project
- Vrije Universiteit Brussel, with a hybrid
vehicle project
- University of Roma La Sapienza, with a
battery electric vehicle and a hybrid car
- Politecnico of Torino, with a fuel cell
car and with a hybrid system project
- University of Terrassa (Spain), with a
hybrid system project
- University of Marche (Italy), with a
battery electric vehicle
- University of Salento (Italy), with an
electric-solar vehicle
- University of Padova, with a tilting body
3 wheel vehicle.
A description of participant vehicles to the
dynamic events is presented in the following
paragraph.
3 New technology vehicles
3.1 Hyb-alpha, by ETH Zurich Team
Formula Electric and Hybrid Italy objectives,
addressing innovation and energy efficiency, in
addition to operating performance, were
considered, by ETH Zurich Team, consistent
with its aim to develop a sport car with new
power train and demonstrate the potential of new
propulsion systems.
The car was developed and realized by students
of the Mechanical and Electrical Engineering
Department of ETH supported by students of the
University of Applied Sciences and Arts Luzern
and by many other people from within ETH and
also from industrial partners [2].
The power train
The power-train of Hyb-alpha consists of a 250
cm3, single cylinder, 4 stroke gasoline engine,
that is connected via a clutch and a vibration
damper to the output shaft of a 60 kW electric
motor. In parallel operation mode this power
train can deliver more than 100kW to the shaft. A
gearbox with an integrated limited slip
differential connects the this shaft to the wheels.
The kinetic energy of the vehicle is recuperated
when braking with the electric motor used as
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generator and stored in batteries with a maximum
charge of 5 kW. (see fig.1)
The electric motor is permanently connected to
the wheels. The combustion engine serves, to a
grater or lesser extent, as a range extender and
has very limited torque and power. However, if it
can be permanently operated at the optimal load
and efficiency, it can significantly support the
batteries. For low vehicle speeds, the combustion
engine is disengaged by a centrifugal clutch.
Although being a parallel hybrid, the control
strategy of the system is closer to one of a series
hybrid, i.e. using the combustion engine in the
majority of cases as range extender.
Fig.1: Energy flow chart of the hybrid system
Electric Motor
A synchronous permanent magnet 3 phase motor,
the HSM 6.17.12 of the Swiss company Brusa
Electronics was selected, considering in
particular the drive torque, the recuperation brake
torque and the efficiency.
Fig.2 shows the specifications and Fig.3 the
torque, power and efficiency versus speed of the
motor.
Fig.2: Specifications of the electric motor
Fig.3: Torque, power and efficiency of the
electric motor versus speed
Combustion Engine
Out of various possibilities, the Swissauto
Wenko AG, 250 cm3, one cylinder four stroke
engine was chosen, because all engine
specification were available and because of the
lowest fuel consumption (roller bearing at all
bearing positions, optimised lubrication,
optimised cooling), with further other
advantages.
The engine had to be modified for the new Hyb-α
hybrid concept.
The original engine has a top speed of over
10’000 rpm. However, the maximum speed of
7’000 rpm is necessary for the hybrid drive only.
Hence, a modified camshaft was provided by
Swissauto in order to optimize the gas exchange
for the new boundary conditions.
• The engine is originally fitted with a carburetor.
To have full control of the engine, and to be able
to adjust the air/fuel ratio and the ignition timing
in every operating point individually, the engine
was re-equipped with an electronic fuel injection
and ignition, using the WALBRO engine control
unit, as well as with an electronic throttle
actuator. Additional sensors for the following
measurement variables had to be installed: Intake
manifold pressure, temperature of the intake air,
engine speed, TDC of the crankshaft, air/fuel
ratio, and temperature in the exhaust.
To comply with the competition rules, the engine
has to be equipped with a restrictor of 12.9 mm
diameter. This yields in a strongly reduced
air flow into the intake manifold. Hence,
reduced engine performance results from this
limitation. To increase the reduced torque, a
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pressure recovery within a Laval nozzle
downstream the restrictor was realized. Since the
engine is a one cylinder four stroke engine,
strongly varying air flow is expected. Thus an
intake manifold with a volume of 4 liters is
chosen to damp the air flow variations.
Since the electric motor is permanently
connected to the rear-wheels, the combustion
engine can be started simply by closing the
clutch between the ICE and the electric motor,
while en route. Therefore, the electric starter can
be omitted.
Fig.5: Assembled power train
Batteries
There are many criteria for choosing the battery
type: power density, energy density, availability,
price and safety.
Lithium Manganese Oxide cell of the size 18650
was chosen, featuring energy density of 110
Wh/kg and power density of 1.7 kW/kg.
Compared to Lithium-ion polymer, Lithium
Manganes Oxide has an energy density, which is
approximately 30% lower.
However, Lithium-ion polymer batteries can
chemically react, if they are overstressed or
mechanically damaged.
The used manganese cell is inherently fail-safe
unless it is mechanically destroyed.
Another battery type with comparable energy
density and higher peak performance is the
Lithium Iron Phosphate battery. The drowback of
these cells is, that they have to be balanced (the
voltage of every cell has to be controlled
individually), which is not the case for the
Lithium Manganese Oxide cells.
A configuration of 100 cells in series and 10 cells
in parallel is used. This results in a nominal
voltage of 370V and a typical maximum current
of 100A.
The control of the complete power train is
custom made by the students and runs on a rapid
prototyping computer.
Several control loops coordinate all components
and optimise safety, efficiency and drivability of
the vehicle.
This new type of hybrid system has a large
potential to be applied and used in conventional
vehicles.
Fig.6 shows the space frame of the vehicle, with
the stiffening structure required for the safe
integration of batteries and the power train.
Fig.6: Space frame of the car.
The picture below shows the car presented by the
ETH Zurich team for the competition at Fiat
Safety Center during the Award Ceremony in
wihich it was awarded with the first prize in the
Class 1.
3.2 IDRA 08 and the Team H2politO
IDRA 08 is the first low consumption prototype
developed, assembled and tested by the Team
H2politO a student team of the Politecnico of
Torino. Starting from an “idea” the vehicle has
been projected, designed and realised by twelve
engineering students.
Essentiality, minimalism, easy to use were the
basic criteria of the whole project.
The prototype has three wheels: one rear wheels
and two front wheels.
The propulsion system has been realised with a
hydrogen fuel cell (1 kW), combined withan high
efficiency brushed electric motor (0,2 kW).
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The fuel cell is supplied with hydrogen stocked
at 200 bar.
The transmission is chain type (figure 1) and it
allows to connect the electric motor to the
driving rear wheel.
Figure 7 – Transmission system
The study of the power system was particularly
focused on the fuel cell (figure 2) and electric
motor integration, studying an easy system to
reduce losses of energy in the fuel cell and tuning
the power train consumption to the race strategy.
Figure 8 – Fuel cell system
The framework was made on welded steel tubes
25 CrMo4. Honeycomb panels (aluminium
sheets and glass fiber reinforcements) were used
as supports to divide the engine compartment. A
specific support for the driver was realised.
The steering system is simple, light and safe and
gives a wide range of possible regulation, that
allows mechanics and the driver to obtain
optimal driving performance.
Particular attention was paid to ergonomics.
Everything was designed to give accessibility to
commands with a minimum driver effort.
Figure 9 final IDRA 08 without body.
In the above picture you can see particular:
framework, steering system, wheels, power train,
all ready the first test on the road!
To verify the driver safety, many numeric
simulations (like crash-tests) were performed on
a computer, focusing on frontal and lateral
crashes and vehicle overtuning.
The aerodynamics was studied to reduce the
resistance to the motion, using the aerodynamic
flows to create lift and the final vehicle shape has
been obtained using computational fluid dynamic
programme.
The coefficient Cx obtained with simulation
procedure and experimental tests made on wind
tunnel are 0.237 and 0.26 respectively.
Special attention was also given to the ventilation
of the cockpit and the engine compartment.
The bodywork is in carbon fibre to minimize the
weight and it was studied both for aerodynamic
purposes and to reach an aggressive and good
looking design.
The production process helped to obtain an
excellent surface finishing.
The covering is made of polycarbonate and was
studied to reflect the solar light and to allow a
good driver’s visibility. This system ensures an
easy and quick opening operation and maximum
safe getting out the prototype.
The braking system is composed by two
hydraulic circuits separated between front and
rear, with a disk brake each wheel.
The system was designed with a compact layout
to have less clutter and weight; it has high
performance and it is linked to the frame through
ultra-light bolts and titan screws.
The rim is custom-made and completely realized
of carbon fibre, material that gives it a significant
lightness (the weight is 0.4 kg) without reducing
its resistance and its structural stiffness.
The innovative realization allowed both to have a
correct held of the tyre pressurized at 6.5 bar and
to obtain the rim in just one piece, avoiding the
use of heavy structural glues.
Also the hubs, made of anodised aluminium,
were designed especially for the application on
the vehicle. Inside them, the bearings are
mounted with a properly studied process, to have
minimum friction and reduce the weight.
The prototype is shown in figure 10.
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Figure 10 – Final IDRA08 on the test track
The prototype has a weight of 65 kg, a length of
3 m, awheel track of 0.8 m and a height of
0.65m.
IDRA08 has participated at the Shell Ecomarathon
2008 on Nogaro circuit (France)
obtaining a fuel economy of 940 km/l with the
equivalent energy of one litre of petrol.
IDRA has then participated at Formula EHI
(Electric and Hybrid Italy) at Fiat Safety Centre,
Orbassano (Turin). In this contest, the prototypes
confront themselves with different kind of
challenges: fuel consumption, climb ability test,
handling, performance and pursuit. Even if its
technical characteristic favour the low
consumption of energy, it was possible to
evaluate the dynamic behaviour of IDRA08.
Other than joy for the clear victory in the
endurance test, IDRA08 impressed for its agility
among the cones on the race track for the
excellent brakes even nearer to the limit point
before curves, for its behaviour on the racetrack
in spite of the disconnection of the asphalt,
lateral accelerations and transfer of load.
The good capacity of the pilot and the hard and
important work of all Team has allowed to obtain
the third prize in the category 2 (figure 5)
3.3 VEUS 08
Air pollution and greenhouse gases emissions
can be largely attributed to the systems of
transportation and mobility, key element for
passengers and/or goods movement. Concerning
transportation, “Mobility can be defined as the
ability to move and put in contact goods and
people in space and time”. This ability is crucial
for the socio-economic development of a
country. In fact, transportation allows people to
access goods and services, creates employment
opportunities, ensures the optimal movement of
goods, supporting local development processes.
In 1990 the total emission levels of carbon
dioxide produced by the transport sector was
about 1.25 billion tons, about one fifth of total
emissions coming from the use of fossil fuels.
With the European Council of 8 - 9 March 2007,
the European Union agreed to reduce emissions
by 30% compared to 1990 emissions, with the
target of reduction of 60-80 % within 2050.
With current policies on energy and
transportation, the emission levels of CO2 in EU,
instead of decreasing, will increase of 5% by
2030.
The Commission also considers that the most
significant energy savings can be achieved
nowadays only in certain areas:
• the tertiary sector (residential and
commercial), with an estimated potential
reduction of 27% and 30%;
• in manufacturing, with possible savings
around 25%;
• in the transport sector, with an estimated
consumption reduction of 26%.
The idea of the VEUS 08 project was born in the
Faculty of Engineering of the University of
Salento, in order to meet these goals.
VEUS 08 (Solar Urban Electric Vehicle) is a
photovoltaic-electric vehicle designed to be
used exclusively in urban area, with the purpose
of reducing energy consumption and pollution
specially in big cities. It is exclusively
electrically powered; moreover, the battery
recharge is performed, when the car is moving,
thanks to several solar panels positioned above
the whole mainbody, while, when stopping, to
the combined action of the solar panels and the
electric network.
The car was created to promote the use of
renewable energy and is so innovative because
most solar cars are designed only to be used
under controlled conditions on motor - racing
tracks. On the contrary, the goal of VEUS 08
project is to demonstrate a practical use of solar
technology; in this way, manufacturers can adapt
it to mass production of future vehicles.
This is like an economy car limited only to the
short-haul urban action; it is in fact designed for
an autonomy of 100 km and with a limitation of
the maximum speed to 50 km/h.
Carriageway 1,44 m
Rate 1,80 m
Width 1,80 m
Lenght 2,50 m
Heigth 1,40 m
Passenger 2
Load 740 kg
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The electric motor used is a series-characteristic
motor with a rated power of 6.8 kW. The engine
power depends on the speed (v) and the slope of
the carriageway roads (p); in our application, it
has been calculated assuming an average speed
of 40-45 km/h (with maximum speeds between
55-60 km/h which can be reached only on city
streets-speed) and considering a maximum uphill
distance (with slopes of more than 5%) and
on flat roads (slopes less than 3%).
The total capacity of the battery pack has been
determined based on the number of days of
autonomy wanted to be ensured for the vehicle
and according to the maximum daily energy
required. With 12 batteries (6 in the rear of the
car and 6 in the front) a system at 48 V and 345
Ah was obtained.
With this configuration, the car can be driven for
95 km average on roads with slope p ≤ 3% and
for about 5 km on roads with p> 3%, or 90 km on
roads with p ≤ 3%, and 10 km on roads with p>
3% at the average speed of about 40 km/h.
The batteries are recharged connecting the
vehicle to the domestic net (3.3 kW) and by the
contribution of solar panels placed on the
mainbody.
The impact of the car on electric power
consumption and emission of greenhouse gases
has been estimated, if all the power needed for
charging the batteries was produced by thermal
power stations (combined cycle fueled by natural
gas, conventional cycle steam fed fossil fuels);
all of this was done considering data available on
the literature on pollutant emissions of vehicles
in cities, and considering also the pollutant
emission levels (in terms of CO, SOx, NOx,
heavy metals, etc. .) produced by a thermal
power fed with conventional fuels (natural gas,
coal, fuel oil, etc.). These levels of exhaust gases
have been compared with those produced by
internal combustion engines currently equipping
the cars.
Figure 11 – Estimated emissions
The estimated emissions from power plants (Fig.
11) are much lower than those obtained with cars
in urban conditions, whereas the complete
refilling of the car takes about 23 kWh, taken
from the electric network.
Finally, adding the contribution from the
photovoltaic generator to recharge the batteries,
the cost per kilometer is equal to 0.036 €/km for
the VEUS, compared to the average value of €
0.0762 / km calculated for the current cars, with
a saving of over 50% per kilometer.
Energy flows
The power needed for traction is provided
exclusively by the batteries placed in the vehicle.
The recharging process of the batteries is
obtained by connecting the vehicle to the electric
network (3.3 kW) and the contribution of solar
panels placed on the mainbody.
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Figure 12 – Energy Flows a) The car is moving;
b) regenerative braking
When the car is moving, the two sources of
energy are the batteries and the photovoltaic
panels (which recharge the batteries). During
braking, it is possible to recover the kinetic
energy thanks to regenerative braking.
For the preliminary estimation of solar energy
that can be collected by the photovoltaic panels,
the values of global solar radiation at ground
level and on horizontal and inclined surface
extracted from ENEA maps has been considered.
The technical characteristics of the generator are:
􀀹 Max power: 159 W at 1.000 W/m2 and 25° C
(7 panel 7 W, 4 panel 14 W and 2 panel 27
W)
􀀹 Max current: 11,25 A
􀀹 Voltage: 15 V
􀀹 Load: 14,06 kg
􀀹 Surface solar panel: 4,01 m2
The energy (estimated) produced by the panels
is obtained by summing two contributions:
- The energy produced during the travelling
period: Ed
- The energy produced during the parking
period: Ep
The graphs describe the annual trend of energy
output from the generator and power provided
during the travel.
Of course, this energy (and the power) is higher
during the summer months when the solar
radiation values are higher, reaching the
maximum of 45 W (July).
It is estimated an average solar contribution of
about 3%.
Figure 13 – Solar contribution
Conclusions
The goal of the research team of the Faculty of
Engineering is to realize an environmentally
sustainable car designed for the city, being this
car small and easily maneuverable.
In addition to the total lack of emissions during
the driving phase, it should be highlighted the
cost of fuel, estimated at less than 3.50 euro,
which will allow to cover 100 km at an average
speed of 50 km/h (that cost is significantly
reduced if the electric power needed is produced
from renewable sources).
The electric vehicle can therefore be considered
an "environmental vehicle" at the local level and
to users, since it does not emit exhaust gases.
However, this is not true taking into account the
whole energy production process. The recycling
of used batteries as well as the production of
electricity to recharge the batteries must be taken
into account too.
In the worst cases, this electric power is
produced from fossil fuels that release pollutants
into the atmosphere. Therefore, this electric
vehicle, as well as every electric vehicle, can be
classified as clean only if energy required for the
office should be produced from renewable
energy sources (solar, wind, hydroelectric, etc.);
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but the basic advantage is the zero pollution in
the site of utilization, that is mainly in urban
areas, where the life and the activity of the man
mostly takes place.
3.4 Wheel motor of E-SNAKE
The design of the electric propulsion system of
the E-snake started in the middle of the 2006 and
was relying on an existing motorcycle-derived
three-wheel vehicle. The mechanical layout of
the vehicle consists of a tilting front module with
one wheel, a non-tilting rear module with two
wheels of very narrow track, and a four-bar
linkage connecting the two modules. A detailed
description of the mechanical layout can be
found in [1].
The electric propulsion system of the E-snake is
characterized by three outstanding features,
namely the lithium-ion battery with the relevant
management system, the by-wire riding for
conditioning the handlebar commands, and the
in-wheel motorization. Regarding the latter
feature, two equal wheel motors -one for each
rear wheel- propel the vehicle.
The concept of wheel-motor dates back to the
beginning of the last century. In 1902 F.Porsche,
while working at Lohner Co. of Vienna, devised
an electric motor to be built-in into the wheels of
a car. Compared to the traditional electric
powertrains, the in-wheel motorization exhibits
distinct advantages. The main advantage is that
no differential, axle shaft and, possibly, gear is
needed, thereby reducing complexity, weight and
room of the powertrain, and improving its
efficiency. The main shortcomings are the
addition to the unsprung mass of the vehicle and
the mechanical and thermal solicitations
experienced by the motors. The recent
advancements in the electric motor technology
has allowed the manufacturing of compact and
reliable wheel motors of low-medium size that
develop torques up to a few tens of Nm and are
employed in scooters and motorized bicycles.
Efforts are being held to set up wheel motors of
larger size to propel the cars and some prototypes
have appeared.
The wheel motor used in the E-snake is a threephase
permanent magnet machines of brushless
dc type, i.e. with the back emf of trapezoidal
waveform. Differently from the conventional
arrangement, the wheel motor has an inner stator
and an outer rotor. The stator contains
concentrated windings and is fastened to the hub
of the wheel. The rotor contains the rare earth
permanent magnets (Sm-Co) and constitutes the
rim of the wheel. The motor has a radial-flux
structure in order to achieve high field intensity
across the stator windings and zero magnetic
force between the rotor and the stator.
Each motor is fed by a separate inverter with
Mosfet transistors. Two inverter legs are
conducting at a time, where the feeding sequence
of the motor phases is dictated by Hall sensors
placed on the stator. The resulting brushless dc
drive imposes currents of basic square-shaped
waveform into the phases.
The control system of the drive operates in the
voltage mode with battery current limitation. The
voltage reference is reproduced at the inverter
output by varying the duty-cycle δ of the
transitors, being their switching frequency of 14
kHz.
Torque- speed characteristic of the wheel motor
Brushless dc motor back emf at 75 rpm
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A capacitor filter at the inverter input makes the
current drawn by the battery nearly continuous.
The control system detects this current and, when
it exceeds a settled limit, manipulates the dutycycle
so as to clamp the current. This implies that
the torque-speed characteristics of the drive are
linear for small torques and merge into an
hyperbolic-like curve for high torques, which are
requested especially at low speeds. This behavior
helps riding the vehicle when starting and
climbing. The control system, moreover, has an
input termed torque boost that increases more
than two times the settled limit of the battery
current thus doubling the torque developed by
the drive at a given speed. The torque boost is
entered by the handlebar and is enabled for a few
tens of seconds.
The main data of the two brushless dc drives
with wheel motor equipping the E-snake are
reported in Tab. 1. Note that for a motor rotation
of 620 rpm, the speed of the vehicle is about 47
km/h.
Tab. 1. Main data of the brushless dc drives with
wheel motor
Rated voltage 48 V
Pole pairs 8
Rated dc link current 45 A
Torque at 620 rpm 30 N·m
Peak dc link current 100 A
Peak torque at 340 rpm 90 N·m
Weight (with tire) 14 kg
Wheel diameter 10 inches
Outer wheel radius with
tire
0.2 m
Inner view of the wheel motor with pole
direction
Wheel motor front and lateral views
Three-wheel vehicle rendering
4 Technology outcomes
The presentation of new technology vehicles has
shown various spin off to new developments and
implementation at industrial level.
From Hyb- alpha:
- the operational demonstration of the hybrid
plug-in concept, with the feeding of the
vehicle with two energy sources, fuel and
electricity and the consequent benefits at the
level of primary energy consumption
- the demonstration of the performance
enhancement of the car due to the hybrid
systems, keeping at the same time a good
energy economy level
- the hybrid systems concept based on the use
of a permanent magnet motor with very high
efficiency and high constant power field,
complemented by two clutches, for the
functions of speed variations.
From IDRA 08:
- concepts and solutions for a very energy
efficient vehicle systems, including weight,
aerodynamics and rolling resistant aspects
- operation of a fuel cell systems in practical
use, with demonstration of reliability and
control capability
- study of ergonomics for easy and
comfortable management of the vehicle.
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From VEUS 08:
- the application of flexible structured solar
photovoltaic panels with appropriate
distribution on the car body
- the integration of the solar systems with the
electric storage system.
From E-SNAKE:
- the in-wheel motorization with two
permanent magnet motors directly integrated
and the relevant electronic control
- the Lithium batteries and the related
management systems
- the by-wire riding
The presentation of the projects produced by
international teams brought a valuable
contribution with indication of development
trends, which are promisingly addressing new
realisations for future Formula EHI editions.
It is worthy to mention the hybrid vehicle
projects of the Vrije Univeriteit Brussel, of
Moscow University, of Univeristy of Terrassa
and University of Roma La Sapienza, which are
intended to give a further development, with
realisation next year.
Further development of battery electric vehicles
were objects of cars presented by Univeristy of
Roma la Sapienza and University of Marche.
5 Conclusion
The fourth edition of Formula EHI brought to be
attention and consideration of the actors involved
in the field of electrically propelled vehicles new
outcomes in technology validations and technical
achievements in the three domains of electric,
hybrid and fuel cell vehicles.
The set up of this type of vehicles takes benefits
from the integration of various technology
elements, which can take profit from the cross
fertilized validation and development.
This is what is been achieve by the result of this
demonstrations, putting at the disposition of the
engineers validation elements and new solutions
hints applicable to different kinds of vehicle.
This type of event is considered to be a strong
stimulus for an international cooperation among
University students, Industry and Research
Institutions to progressively enlarge the asset and
knowledge of the technology for environment
friendly vehicles.
References
[1] G.Brusaglino, A.Doria, P.Guglielmi,
L.Martellucci and M.Razzetti, “Innovation
for ecological sustainable mobility in
formula Electric & Hibrid Italy 2007”,
Proceedings of 3rd European Ele-Drive
Transportation Conference (EET), 2008,
pp……..
[2] Guzzella Lino, Sciarretta Antonio: “Vehicle
Propulsion Systems, Introduction to
Modeling and Optimization”, 2nd Edition,
Springer, 2007
[3] M.Bertoluzzo, G.Buja and R.Pavoni,
“Characterization and Improved Control of a
Brushless DC Drive with In-Wheel Motor”,
Proceedings of 13th International Power
Electronics and Motion Control Conference
(EPE-PEMC), 2008, pp. 1514-1519
[4] S.Wu, L.Song and S.Chei, “Study on
improving the performance of permanent
magnet wheel motor for the electric vehicle
application”, IEEE Transactions on
magnetic, Vol. 43, No. 1, pp. 438-442,
January 2007
Authors
Giampiero Brusaglino graduated
at Politecnico di Torino, Italy, in
Electrical Engineering and in
Aeronautical Engineering. He was
Vice Director at Centro Ricerche
Fiat. He has been President of
A.V.E.R.E. and coordinator of the
EUCAR Interest Group Electric
Vehicles. He is Head of the
CUNA Commission Electric
Vehicles, Chairman of the
Technical Committee CEI-CIVES
and Head of the Italian Delegation
UNI-CUNA.
Dr. Christopher H. Onder is senior
scientist and lecturer at the
Measurement and Control
Laboratory, ETH Zurich.
Research interests: modelling and
control of automotive systems,
highly dynamic testbench
equipment, model-based robust
control
He graduated with honours in
Materials Engineering at the
University of Lecce in 2000. In
2004 he achieved the PhD in
"Energetic Systems and
Environment" at the same
University, with a dissertation on
the analysis of alternative
injection strategies for new
generation Diesel engines. He
collaborated as visiting scholar in
a project for the application of
electrospray technology to the
automotive field at the University
of Illinois at Urbana-Champaign.
It is Author of many national and
international publications. Interest
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fields: analysis of combustion and
non intrusive diagnostic in ICE,
electrosprays, gaseous fuels in
ICE, energetic systems for
sustainable mobility.
Giuseppe Buja is a full professor
of power electronics and the head
of the Laboratory of Electric
Systems for Automation and
Automotive at the Department of
Electric Engineering of the
University of Padova, Italy. His
scientific interests range from
power electronics to fieldbusses
and are documented by journal
and conference papers. In recent
times he has directed research
projects on by-wire systems and
hybrid/electric vehicles. He is a
recipient of the IEEE-Industrial
Electronics Society Eugene
Mittelmann Achievement Award
“to recognize outstanding
technical contributions to the field
of Industrial Electronics”.
Monica Razzetti works in ATA
from 2000; now she is the
Formula Electric & Hybrid Italy
Manager and she is responsible
for the administration and
management of ATA Members.
World Electric Vehicle Journal Vol. 3 - ISSN 2032-6653 - © 2009 AVERE
 davido.extraxim@gmail.com