Luciano Rolando-EU RDD on New Energy and Energy Saving ...

POLITECNICO DI TORINO - ENERGY DEPARTMENT
<strong>EU</strong> RD/D on New Energy & Energy Saving Vehicles
and <strong>EU</strong>-China Cooperation
Two Examples of hybrid urban busses design for the city of Turin
Federico Millo
<strong>Luciano</strong> <strong>Rolando</strong>
Workshop on Electric Buses and Taxis
April 27, 2012 – Beijing
Speaker
<strong>Luciano</strong> <strong>Rolando</strong>

POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S systems
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
2

POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S systems
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
3

POLITECNICO DI TORINO - ENERGY DEPARTMENT
STOP & START ASSESSMENT ON URBAN BUSES:
THE GTT – IRISBUS CASE
The aim of this research activity is the assessment of the potentiality of a urban
bus equipped with a Start & Stop (S&S) system in real world driving conditions
through the analysis of the data collected from a circulating test fleet.
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POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S systems
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
5

Hybrid Vehicles
Benefits:
ENGINE
BATTERY
BATTERY
• Available technology (but not “off-the-shelf”) .
14/11/2011
• Requires several vehicle updates but not radical changes .
POLITECNICO DI TORINO - ENERGY DEPARTMENT
• 3% - 4% Composite FE benefit (NEDC cycle), substantially bigger FE (8-9%) in city drives.
• Favorable cost/benefit ratio.
Start & Stop System – Introduction
ELECTRIC
MOTOR
ENGINE
ELECTRIC
MOTOR
Micro Hybrid
Mild Hybrid
Full Hybrid
Battery
Vehicle
Series
Hybrid
Start & Stop System
• The automatic stop of the engine during
normal idle, when the vehicle is stationary.
• The automatic start of the engine in response
to driver or other inputs, usually determined by
clutch action, brake release.
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FEATURES:
• Non-intrusive Micro-Hybrid system
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Start & Stop System – Introduction
To implement a S&S system there are two possibilities:
Enhanced Starter Belt Alternator Starter
• Standard starter with enhanced performance & durability.
• No power electronic required (low cost).
• Reduced noise and start time (compared to key cranking).
• Minimal integration impact.
• 12V conv. electrical system
• w/ add. buffer battery or DC/DC converter
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FEATURES:
• Non-intrusive Micro-Hybrid system
• Use 2kW (approx) motor-generator unit (MGU) in place of
alternator
• Power electronics control the MGU
• Quiet and fast cranking
• Requires adaptation of belt accessory drive (new tensioner
system)
• Conventional starter motor for cold cranking, system
safety
• It can also enable regenerative braking
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POLITECNICO DI TORINO - ENERGY DEPARTMENT
Start & Stop System – Introduction
Despite of its simplicity, a Start & Stop system introduces several issues in the vehicle design:
27/04/2012
8

14/11/2011 8. ...
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Start & Stop System – Introduction
Nowadays S&S systems represent an established solution from passenger cars.
On the other hand, urban buses represent a more challenging application since they introduce additional issues
that have to be taken into account in the design process:
1. Longer time spent in idle (about 26% for passenger cars vs. 45% for busses).
2. Higher number of stops (3.85 num/km).
3. More severe requirements of the engine cranking phase (higher frictions).
4. Higher electrical loads (critical for the battery).
5. Higher NVH issues.
6. Feelings of the drivers.
From City-cars To Supercars
7. Effects on the vehicle reliability.
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POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S systems
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
10

Engine start & stop functions are managed by
the Multiplex.
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Case study: Citelis Irisbus
The bus considered in this study features a S&S system based on an enhanced starter (no regenerative braking)
Citelis Irisbus:
• Dimensions: 18 m
• Doors: 3 o 4
• Application: urban / suburban
• Test Fleet: 2 Diesel and 2 CNG
Vehicles
Engine: IVECO Cursor 8
• Displacement: 7.8 liter
• Fuel: Diesel/CNG
• Power: CNG 243 kW Diesel: 280
kW
Battery integrated by Supercapacitors:
• 22 units
• Energy: 120 kJ
• Voltage: 52V
• Charge Current : 100A
• Discharge Limit: 500A
Battery Packs (120 Ah)
Supercapacitor
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Implemented Control Strategy:
S&S Enabled:
Stop Conditions
Restart Conditions:
27/04/2012
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Case study: Citelis Irisbus
- Switch S&S mode ON
- Coolant temperature > 45°C
- Driver on his driver seat
- Gearbox not in Rear gear position
- Vehicle speed > 5km/h during the previous run.
- Vehicle speed < 3km/h; Air pressure for servosytems > 9 Bars
- Supercaps energy > 65 KJ ( in order to save the energy of the main battery during the
start )
- Driver present on his seat
- No action on the inhibition pedal
There is no condition to restart. Any action on the accelerator pedal will
launch the restart of the engine
If the energy stored in the supercap drops below 65 kJ the engine is
automatically restarted
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Remote Monitoring System: INTELLIBUS:
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Each vehicle is equipped with a remote monitoring system that through a GMS SIM card allows the recording of
the main trip data.
27/04/2012
Case study: Citelis Irisbus
The aim of this function is to get information from the vehicles and
especially from the Stop&Start use, during the test drives.
The Intellibus system with its dedicated fleetweb application from
Digigroup was used.
This solution is able to deliver through a dedicated website, to all
authorized users, real time or daily reports.
In addition to the usual service monitoring developed by the Intellibus
for the Citelis, additional features concerning the S&S function have
been added.
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Remote Monitoring System: INTELLIBUS:
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Case study: Citelis Irisbus
Available Information
Data Analysis
Trip Map – Event
Representation
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POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S systems
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
15

POLITECNICO DI TORINO - ENERGY DEPARTMENT
The first analysis on the tested vehicle was performed on a regulatory driving cycle suitable for urban
busses applications:
Experimental Setup:
Cycle SORT is a standardize and modular driving cycle for fuel consumption calculation
• Vehicle: Citelis CNG Bus
Results: data from SORT Cycle
SORT1 SORT2
Average Speed: 12 km/h Average Speed: 18 km/h
• Vehicle mass: 23725 kg (vehicle + 1 passenger of 65 kg).
• The simulations were performed at FIAT test circuit (Balocco).
• The idle fuel consumption is measured through a dedicated measurement system to achieve higher
accuracy.
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120%
100%
80%
60%
40%
20%
0%
100% 100%
90%
SORT1
Supercap Supercap
En. Before En. A0er
98,0kJ 98,0kJ
96,0kJ 97,0kJ
98,0kJ 97,0kJ
97,0kJ 97,0kJ
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Results: data from SORT Cycle
Fuel ConsumpAon ReducAon
SORT1 SORT2
94%
SORT2
Supercap Supercap
En. Before En. A0er
83,0kJ 100,0kJ
85,0kJ 101,0kJ
100,0kJ 102,0kJ
101,0kJ 100,0kJ
Conven2onal
S&S
• The S&S System shows
significant reduction of
the fuel consumption
• SORT1 has greater
reduction due to the
longer idle time.
The use of the S&S system
does not affect the energy
stored in the supercap.
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POLITECNICO DI TORINO - ENERGY DEPARTMENT
Results: data from circulating test fleet
All the tested vehicle travel the same route from Turin downtown and to the suburbs.
Length of the route: about 14 km
27/04/2012
Turin Downtown
San Mauro Torinese
Average: 204 km
• A time horizon of about two weeks was considered as reference interval to enable or
disable the S&S system.
• This choice allows testing the system on the same boundary conditions (traffic, weather)
• For sake of brevity in this presentation only the results of Diesel vehicles will be presented.
• Data from November 2011 to March 2012 will be considered
Average: 3.69 num/km
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POLITECNICO DI TORINO - ENERGY DEPARTMENT
Results: data from circulating test fleet
Focusing on a shorter time-horizon it is possible to highlight the features of the S&S system
When the S&S is enabled, the number of vehicle stops with the
engine off is quite close to the total number
Number of Events / km
Average Stops 3,71
Average S&S events 3,05
A significant number of S&S events is inhibited by the driver while
there are no inhibitions related to low energy stored in the
supercapacitors.
S&S disabled: about 38% of
the time spent in idle
S&S enabled: about 27% of
the time spent in idle
Consequently also a reduction of the fuel consumption in
idle condition can be observed 19

POLITECNICO DI TORINO - ENERGY DEPARTMENT
Results: data from circulating test fleet
Globally the comparison of the vehicle fuel consumption points out that the S&S system achieves a reduction of
about 7% in real world driving conditions
27/04/2012
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14/11/2011
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Results: data from circulating test fleet
This study also included a dedicated maintenance program to monitor any effects of the S&S system on the
components of the driveline
The starter was found to be the killer component: it represents the main cause of vehicle failure related to the S&S system
Vehicle 791 792 1310
Starter Maintenance Date date 27/05/11 23/03/11 31/03/11
Actuations num 44’730 32’494 38’357
Working hours h 2012.1 1377.1 1679
Travelled Distance km 32’979 20’150 26’056
Actuations since last maintenance num 23’967 //// ////
Nevertheless the failure of the starter always occurred very close to the nominal life set by the manufacturer (40000 actuations)
New Starter Failed Starter
• The brush wear was the main
cause of the starter failure.
• This phenomenon produced
sparks and an overheating of
the system which significantly
damaged also the collector of the
rotor.
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POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S system
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
22

POLITECNICO DI TORINO - ENERGY DEPARTMENT
• Up to 77’000 km/vehicle (250’000 km total) travelled by the test fleet vehicles without any
major failure of the system.
• The data collected from the circulating fleet highlighted a lower usage of the vehicles when
the S&S is enabled.
• 7% average fuel consumption savings on urban trips during 5 months monitoring
• S&S system almost never inhibited due to supercapacitors low energy
• Two weeks seems to be a reasonable time-horizon to disable and/or enable the S&S
system. Therefore the performance of the system can be tested on the same vehicle and
on the same trip.
• The analysis of the broken starter shows that main cause of failure is the wear of the
brushes which produced sparks and an overheating of the components.
27/04/2012
Conclusions
23

POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S system
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
24

POLITECNICO DI TORINO - ENERGY DEPARTMENT
HYBUS
The New Eco-friendly Hybrid Bus
The main targets of Hybus, the new eco-friendly bus developed in the framework of the AMPERE project, are
• The study of a modular hybrid propulsion system suitable for urban busses.
• The conversion of vehicles currently equipped with Euro 0–1–2 engines into buses with serial hybrid power
packs.
• The evaluation in real world driving conditions of the performance of the proposed hybrid architecture

POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S system
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
26

1. Electrification of the powertrain:
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Motivations
• Series hybrid architecture was found to be the most suitable for this kind of applications since it can be easily adapted to the
chassis layout and allows to optimize the interiors of the vehicle.
• Moreover, since the driving schedule of a urban bus is usually well-known, the energy management system of the vehicle can be
design to minimize the use of the internal combustion engine and exploit the connection to the grid to recharge the battery at the
end of the mission.
2. Revamping:
• The conversion of an old conventional vehicle equipped with an internal combustion engine to a hybrid vehicle has the following
advantages:
1. it reduces pollution in our cities, and makes it possible to cut costs and capital spending.
2. The revamping offers a saving of approximately:
• 45% in comparison with a new Diesel Bus
• 50% in comparison with a new CNG Bus
• 60% in comparison with a new hybrid Bus
3. The revamping process also helps to solve the problems related to the elimination of obsolete vehicles.
4. Possibility to exploit public fund for low emission vehicles.
5. The road tests in a typical urban cycle has confirmed an FE reduced of 40% respect to a new Diesel Bus
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POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S system
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
28

• Max Speed: 65 Km/h
• Max Grade = 14 %, up to 15 km/h
• Pure electric drive range = 40 km
• Vehicle Mass (Standard A): 11.200 Kg
• Vehicle Mass (Standard F) 18.400 Kg
POLITECNICO DI TORINO - ENERGY DEPARTMENT
HYBUS: the prototype
Performance of the vehicle:
• Min acceleration: 1,1 m/s 2 29

Series Hybrid Powertrain:
• The old internal combustion
engine will be updated with an
Auxiliary Power Unit based on
a <strong>EU</strong>RO5 –Diesel engine
• The gearbox will be substituted
with a electric powertrain made
up of two electric motors
• Installation of a Li-ion battery
and relative BMS
• Electrification of the main
accessories
• Integration of the new
powertrain and of the old
electric systems
POLITECNICO DI TORINO - ENERGY DEPARTMENT
HYBUS: the old vehicle
A old IVECO 490 <strong>EU</strong>RO1 of 1994 represents the vehicle to be restored
• Restyle of the interiors.
• The weight of the vehicle.
• The brakes and the steering system.
27/04/2012
Interiors
• Change of the rear structure to install the battery.
• Installation of the new electronic systems.
These updates will keep unchanged:
Body
• Restyle of the main
components of the
body and change of
colors.
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The main system accessories are
electrified in order to achieve high
efficiency.
Battery pack: it is made up of 4
standard modules series
connected, corresponding to a
total energy of 100kWh and
150kW (max).
The Auxiliary Power Unit
consists of a 1.3 liter Diesel
engine (66 kW) connected to a PM
electric generator.
External Recharge: the SOC can also be
restored connecting the battery pack to the grid
through a 7kW – 220V charger installed on
board
POLITECNICO DI TORINO - ENERGY DEPARTMENT
HYBUS: Vehicle architecture
The HyBus relies on a series hybrid architecture
The electric traction is
performed through 2 PM
90kW/215Nm electric
motors (max) connected to
the wheels through a fixed
gear (ratio = 8:1)
A dedicated ECU manages the
hybrid powertrain, the diagnostic
and safety of the vehicle.
24V Network: the low voltage
auxiliaries are supplied by the
battery pack through a dedicated
DC/DC converter

POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S system
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
32

TRACTION
BATTERY PACK LI-ION
• FAAM Capacity 100 kwh; Power 150 kw;
Weight 1.000 kg
• 2 EV Motor (Magneti Marelli) in parallel
(P nom 90kW; P peak 180 kW; 16.000rpm;
Max Torque 215 Nm)
• Transmission: summation reduction
gearbox; ratio 8:1
POLITECNICO DI TORINO - ENERGY DEPARTMENT
HYBUS: Layout of the powertrain
APU
1.3 MJT FPT Small Diesel Engine (66kw) + Electric Generator (Magneti Marelli)
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Engine Bay
27/04/2012
Hydro assist steering
pump
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Thermal Engine
SDE(66kw)
Inverter
HYBUS: Modular Approach
REAR VIEW
Air Compressor
Radiator
Electric Motor
Cooling System
SIDE VIEW

SIDE VIEW
POLITECNICO DI TORINO - ENERGY DEPARTMENT
HYBUS: Modular Approach
REAR VIEW
Oil pump
Engine Bay
Inverters
Parallel electric engines
(nominal 90kWx2; peak 180 kWx2
16.000rpm, 430 Nm max)
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Pack battery:
POLITECNICO DI TORINO - ENERGY DEPARTMENT
SIDE VIEW
HYBUS: Modular Approach
Carry-over from a pure electric bus of Valence cells:
Total power 150 Kw Capacity 100 kw/h
Total weight including cable and cooling ~ 1.000Kg

POLITECNICO DI TORINO - ENERGY DEPARTMENT
HYBUS: Before Revamping – After Revamping

POLITECNICO DI TORINO - ENERGY DEPARTMENT
HYBUS: Before Revamping – After Revamping
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POLITECNICO DI TORINO - ENERGY DEPARTMENT
Summary
1. Stop & Start Assessment on Urban Buses:
• Introduction: a brief introduction on the S&S system
• Case Study: description of the system taken into account
• Results: main findings of the projects on both regulatory driving cycles and real world driving
conditions
• Conclusions
2. HYBUS: The New Eco-friendly Hybrid Bus
27/04/2012
• Motivations
• The prototype: description of the main features of the vehicle.
• The Modular layout: overview on the layout of the revamped vehicle
• Awards
39

POLITECNICO DI TORINO - ENERGY DEPARTMENT
HYBUS: Awards
The vehicle concept achieves the following awards:
• Premio all’Innovazione Amica dell’Ambiente” (Legambiente)
• Funding from Regione Piemonte to support the vehicle experimenta2on
• The prototype was also men2oned on the main Italian newspapers
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27/04/2012
POLITECNICO DI TORINO - ENERGY DEPARTMENT
Thank You
for Your Kind Attention!
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