development of a lightweight plug-in hybrid electric vehicle demonstrator

8/2/2019 Development of a Lightweight Plug-In Hybrid Electric Vehicle Demonstrator

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EVS-25 Shenzhen, China, Nov. 5-9, 2010

The 25th World Battery, Hybrid and Fuel Cell Electric Vehicle Symposium & Exhibition

Development of a Lightweight Plug-in Hybrid Electric Vehicle

Demonstrator

Girish Muraleedharakurup, John Poxon, Andrew McGordon, Paul Jennings

WMG, University of Warwick,

Coventry, CV4 7AL, UK

[email protected]

Steve Cousins, Kevin Lindsey

Axon Automotive Ltd,

Wellingborough, NN29 7RL, UK

Abstract - This paper presents results and learning from the real life development of a technology

demonstrator vehicle Axon60. Axon60 is a light-weight plug-in hybrid electric vehicle, part of the

Low Carbon Vehicle Innovation Platform sponsored by the UK Technology Strategy Board and led by

Axon Automotive Ltd in partnership with Powertrain Technologies Ltd, Scott Bader and WMG. The

Axon60 uses a lightweight recycled carbon fibre structure, multi-fuel capable combustion engine and

an electric motor to achieve fuel economy of over 100mpg over legislative drive cycles and less than

50g/km of CO2. The plug-in hybrid vehicle using a 2kWh battery pack is able to achieve 10 miles of

electric only operation due to its lightweight aerodynamic design and highly efficient powertrain. This

paper shares the experiences gained during the conceptual studies in light weight body structure

development, driveline selection and prototype vehicle development. Copyright 2010 EVS25

Keywords: Hybrid vehicles, Plug-in Hybrid Vehicles, PHEV, Demonstrator, Lightweight.

1. IntroductionThe challenge to reduce greenhouse gas

emissions is forcing vehicle manufacturers to

aggressively look at the energy usage when

vehicles are designed, manufactured, used and

recycled. Road based transport currently

accounts for approximately 21 per cent of the

UK CO2 emissions and is seen as a priority

sector by the UK government [1]. The UK

government has set a target of 40% reduction in

greenhouse gas emissions by the end of 2020.

Various routes have been suggested to reduce the

road based CO2 emissions such as alternative

fuels, improvements in internal combustion

engine, hybrid powertrains and lightweight

vehicles [2]. A plug-in hybrid vehicle with its

low local emissions is one of the most promising

alternatives to conventional vehicles [3].

As part of the Low Carbon Vehicle Innovation

Platform sponsored by the UK Technology

Strategy Board, Axon Automotive in partnership

with Powertrain Technologies Ltd, Scott Bader

Ltd and WMG is leading a project to launch a

new lightweight plug-in hybrid vehicle Axon60. The new car is capable of achieving

high levels of energy efficiency without

compromising driver safety and comfort. The

project aim is to launch a plug-in hybrid

demonstration vehicle by Q1 2011 to assess

technical possibilities, user experience and

market potential for light weight plug-in hybrid

vehicles in the UK. This paper presents results

and experiences from real life development of

drivetrain components and control strategy of


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the prototype vehicle.

2. BackgroundIn a study undertaken by the authors of this

paper, it has been forecasted that by 2020 up to

7.5% of the new vehicle registrations will be

hybrid vehicles [4]. Figure 1 shows the likely

adoption of hybrid electric vehicles (HEV) in the

UK. As highlighted in the study, factors such as

initial cost, charging infrastructure etc need

addressing to increase the market share of hybrid

vehicles in the UK.

Figure 1: Forecast of HEV growth in the UK

Several initiatives to support the adoption of

Low Carbon Vehicles (LCV) in the UK have

been launched by the Department for Transport

(DfT). One such initiative is the Low Carbon

Vehicles Innovation Platform set up by the

Technology Strategy Board (TSB) to support

programmes to deliver innovative solutions for

the automotive industry.

To financially support early adopters of hybrid

vehicles, the DfT also announced a grant of

5000 to low emission vehicles meeting certain

performance criteria outlined in Table 1 [5].

The Axon60 is one of the LCV projects

supported by the TSB to advance the uptake of

plug-in hybrid vehicles in the UK. The Axon60

is a two-year project which started in November

2008 with an aim to gather experience in

developing and launching plug-in hybrid

vehicles (PHEVs) in the UK market.

Table 1 : DfT financial incentive requirements

Description Requirements

Vehicle Type M1 (i.e. cars only)

Must be

- Battery electric- Plug-in hybrid or- Hydrogen fuel cell car

Emissions 0g/km for EV

Max 75g/km PHEV

Vehicle

performance

Min range 70 miles (113

km) EV

Min range 10 miles (16

km) PHEV

Max speed of at least

60mph (96kph)

Warranty Vehicle:

- 3 years or 75,000miles (120,000 km)

Battery

- 3 years- 5 (if requested by

consumer)

The project aims to develop a PHEV

demonstrator with an All Electric Range (AER)

capability of at least 10 miles over realistic drive

cycles. The demonstrator vehicle will be used to

understand technical possibilities and limitations

of hybrid vehicle components in real world

conditions.

The project is being carried out by a consortium

of four partners responsible for different aspects

of the vehicle development:

-Axon Automotive Ltd :Project management, Vehicle design,

Vehicle construction

-Powertrain Technologies Ltd:Engine development, Continuously

Variable Transmission (CVT) development,

Powertrain packaging

-Scott Bader Ltd:Resin development

2000 2005 2010 2015 2020 2025 20300

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Sales

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Actual Sales

95% Confidence Interval


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-WMG:Drive cycle analysis, Hybrid vehicle

component selection, Control strategy

development, Cost Benefit Analysis

3. Axon60 vehicle architectureThe Axon60 is being developed to meet the

European Union M1 class category (2007/46/EC)

and hence has to meet certain technical

requirements.

To determine the preferred hybrid vehicle

architecture the team first did a market study to

identify the current competition and created a

comparison matrix. Once the comparison matrixwas generated a detailed analysis of different

hybrid vehicle architectures was conducted to

estimate the cost vs. benefit of each architecture.

While undertaking this analysis following

criteria were considered:

- Low cost route to 50g/km of CO2- Electric only operation capability- Drivable in real world conditions- Stop-Start capability- Regenerative braking capability- Minimum battery life of 3 years- Possibility for Vehicle-to-Grid (V2G)

An initial comparison matrix was developed by

WMG to compare the existing competition.

Vehicles which belonged to the A segment as

defined by UK SMMT were considered for

comparison. Some basic performance criteria

such as power-to-weight ratios and specific

power were calculated for all the existing car

models. Figure 2 shows the Axon vehicle when

compared to existing vehicles in A segment.

Once the performance metrics were identified, 8

hybrid vehicle architectures were considered for

the Axon project. These were:

i) Microii) Mild

iii) Seriesiv) Full Parallelv) Through The Road (TTR)vi) Powersplit (PS)vii) Compound Coupled Powersplit

(CCPS)viii) Combined

Figure 2: Axon comparison matrix

The need to have an AER ruled out micro and

mild hybrid architectures. To keep the hybrid

architecture as close as possible to the base Axon

vehicle led to discarding the series, PS and

CCPS architectures. Finally a full parallel

architecture was chosen for the Axon60 vehiclebased on ease of packaging. In this configuration

both the electric motor and engine can drive the

road wheels independent of each other achieved

through the use of a Continuously Variable

Transmission (CVT). The Axon60 vehicle

architecture is shown in figure 3.

Diff

CVTGearbox ICE

GearboxElectric

MachineBattery

Figure 3: Axon60 PHEV architecture

Matiz 0.8

Matiz 1.0

C1

Sirion 1.0

Picanto 1.0

107

Fortwo cabrio

Fortwo coup

Splash 1.0

Aygo 1.0

iQ 1.0

Yaris 1.0

Axon60

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45

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60

65

70

Power/Weight(kW/ton)


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Table 2 is an excerpt from the vehicle technical

specification.

Table 2 : Axon60 vehicle technical specification

Attribute Specification

Acceleration 0-30 mph in 5.5 secs

Max top speed 85 mph

Max kerb weight 650 kg

Passing

performance

30-50 mph in 7 secs

Gasoline range 320 miles

Electric range 10 miles

3.1. Body and structureExisting vehicle designs typically use steel for

body and chassis which make them heavy,

leading to poor fuel economy. One method to

increase fuel economy is by reducing the vehicle

weight and improving aerodynamic efficiency.

The Axon60 project aims to manufacture a

carbon fibre composite car structure at minimum

weight whilst providing greater stiffness in all

aspects than current steel bodied vehicles. The

structure incorporates features which provide

higher impact tolerance for both for minor and

major collisions. The use of composites allow

more flexibility in the vehicle design leading to

better aerodynamic shapes and lower drag

coefficients. Figure 4 shows the aerodynamic

design package for the Axon vehicle.

Figure 4: Axon60 PHEV aerodynamic package

The use of carbon/epoxy composites also

enables the Axon60 to meet weight targets

without compromising safety. The use of

composites helps to keep the total kerb weight of

the vehicle to around 650kg (including hybrid

components).

Figure 5: Axon60 vehicle carbon fibre structure

As shown in figure 5, the Axon60 vehicle uses a

composite structure with lightweight bonded

panels offering several manufacturing as well as

performance advantages such as automated

preform manufacturing, rapid vehicle body

assembling with minimal fixtures and improved

structural efficiency.

The structure is designed to offer high torsional

stiffness at minimum weight to provide crash

energy absorption in excess of a steel structure.

The resultant structure is expected to have aweight of 70 kg and an associated torsional

rigidity of around 15000 Nm/degree.

3.2. Electric motor sizing and selectionIn the initial stages of concept development, DC,

AC induction and permanent magnet

synchronous motors were considered. Before

selecting the motor configurations, several

fundamental factors were considered.

DC motors are much simpler to install, control

and also less expensive, particularly as the DC

motor controllers are much less complex than

AC controllers. Also, DC motors can be driven

above their rated limits for short amounts of time

particularly suitable for vehicle operations such

as overtaking. Yet, DC motors require more

maintenance and the motor design is more

complicated than a comparable AC motor. DC

motors are quite inefficient when used as a


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generator it will not meet some of the

regenerative braking requirements of the Axon

vehicle. It was also difficult to find an

appropriate DC motor size which met the Axon

performance requirements. Although a PM

motor is desirable for PHEVs, due to its highcost, PM motors were not considered for the

Axon application. Hence, for the Axon60 project,

an AC induction motor was chosen due to its

greater efficiency when operated as either a

motor or generator, low cost and availability of

AC motor controllers (off the shelf).

Once the motor architecture was identified, the

motor performance specification had to be

determined. The Axon60 vehicle is primarily

intended to be used as a city car but with

motorway capability. Since the vehicle has to be

used for real world applications, the project team

chose the ARTEMIS urban drive cycle [6] to

determine the power requirements for the AC

motor.

Figure 6 : Axon60 power requirement on the NEDC

cycle

Figure 7: Axon60 power requirement on the

ARTEMIS Urban drive cycle

The power requirements under the New

European Drive Cycle (NEDC) & ARTEMIS

urban cycle are shown in figures 6 and 7. Based

on figures 6, 7 and acceleration requirements for

0-30mph, a 12kW AC induction motor was

selected.

3.3. Battery sizing and selectionFor selecting the appropriate battery for the

Axon60 vehicle the following selection

parameters were considered:

- Energy density- Power density- Capital cost-

Life cost- Cycle life limitations- Depth of discharge- Charge acceptance- Temperature range- Self discharge

The three major battery chemistries (Bi-polar

lead acid battery, Nickel Metal Hydride (NiMH)

battery, Lithium Ion battery) were evaluated

against the chosen parameters for selection.

To understand the energy consumption, a vehicle

simulation model (described later in Section 4)

was developed to calculate the energy consumed

on NEDC and ARTEMIS urban drive cycles.

Simulation results showed that the Axon vehicle

consumed 110 Wh/mile during the urban section

of the NEDC and 181 Wh/mile on the ARTEMIS

Urban drive cycle when operated as a full

electric vehicle. Based on these figures the

required battery capacity was determined as

2kWh for a 10mile AER to preserve battery

lifetime by limiting the depth of discharge.

Due to the small pack size requirements of the

battery, high depth of discharges in the range of

10 - 15C were required to meet the power

requirement for the ARTEMIS drive cycle. The

bi-polar lead acid chemistry was able to meet

some of these criteriasbut could not meet the 3

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year cycle life, low weight/packaging

requirements and hence was not selected. NiMH

chemistry matched most of the requirements but

was not chosen due to high self-discharge rates

and poor availability of suppliers within the UK.

Finally, to keep the weight of the battery systemslow and to meet 3 year cycle life, Lithium-Ion

chemistry was chosen.

Within the Lithium Ion chemistry options,

Lithium Iron Phosphate (LiFePO4) was preferred

due to its superior thermal and chemical stability

as well as having a better cycle life when

compared to other Lithium chemistries such as

Lithium Cobalt Oxide (LiCoO2) or Lithium

Manganese Oxide (LiMn2O4). LiFePO4 are also

more stable under overcharging conditions and

can withstand higher temperatures without

degradation in performance. Even though the

energy density of LiFePO4 is less than LiCoO2,

LiFePO4 can support higher currents and hence

is better suited for the Axon application.

3.4. Internal combustion engine selectionBased on the power requirement calculations

shown in figures 6 and 7, the internal

combustion engine running on gasoline fuel was

selected. The engine is a twin cylinder 500cc

unit producing 26kW at 5000rpm and 40Nm at

3500 rpm. The engine is multi fuel capable and

has Start-Stop functionality. The static efficiency

map of the engine is shown in figure 8.

Figure 8: Axon60 engine efficiency map

3.5. Transmission selectionTo achieve the maximum potential from a hybrid

vehicle the engine and battery will have to

operate at peak efficiencies. In a conventional

vehicle using manual transmission, it is not

possible to keep the engine operating at the best

brake specific fuel consumption (bsfc) region

constantly. However, with a Continuously

Variable Transmission (CVT), it is possible to

operate the engine over an optimum operating

line to achieve best fuel efficiency targets. For

the Axon60 vehicle, a belt driven CVT is being

developed as the transmission. Figure 9 shows

the overall packaging of the engine, CVT and

the electric motor.

Engine Electric machine

CVT

Figure 9: Axon60 powertrain

4. Supervisory control developmentIn a hybrid electric vehicle, the fundamental

requirement of the supervisory controller is to

ensure that the driver demand is met as

efficiently as possible using a combination of the

traction sources available, i.e. gasoline engine or

electric motor.

To develop a suitable supervisory control

requires proper models of the vehicle systems.

This task was carried out using WMGs in-house

vehicle simulation software WARPSTAR

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Engine Speed (rpm)

Torque(Nm)

26kW Engine Map


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which can simulate the fuel economy and CO2

emissions for various drive cycles and different

operating modes [7]. The Axon60 PHEV

architecture developed in WARPSTAR is shown

in figure 10.

Figure 10: Axon60 PHEV WARPSTAR model

The control algorithms for the Axon60 was

developed using Matlab/Simulink and Stateflow.

The Supervisory Control Unit (SCU) is the brain

of the PHEV whose main functions are to detect

the driving modes, driver inputs, sensor signals

and make appropriate decisions based on the

control logic.

A two-level control architecture shown in figure

11 was adopted for the Axon60 vehicle where

the SCU is responsible for the fuel economy and

emissions. The SCU accepts driver demands as

inputs and determines the desired output based

on current vehicle speed, battery SoC etc. These

outputs are then sent to the low level controllers

such as the engine controller and transmission

controller and become the command for the low

level controllers.

Figure 11: Axon60 controller architecture

The design of this SCU was achieved in three

steps:

i) Identification of all possible vehicleoperating states

ii) Identification of all possible transitions based on driver demand and vehicle

status

iii) Check for transition conflicts betweenstates

To generate the control logic it is important to

understand the operating modes possible with

the Axon60 architecture. Once the operating

modes of the each subsystem was identified, the

following vehicle operating modes weregenerated:

- Electric vehicle (EV) only operation- Engine only operation- Engine and electric motor assist- Engine and battery charging- Engine load levelling- Regenerative braking

The electric vehicle only operation state is

entered when the vehicle speed is less than the

EV only speed limit of 35 mph provided battery

state of charge (SoC) is greater than the

minimum battery SoC. The 35 mph cut off was

selected based on the maximum vehicle speed

observed in figures 6 & 7. Over 35 mph the

power requirements is higher than 12 kW which

will drain the battery very quickly and also these

higher speeds are more likely to be sustained for

longer periods. In this mode, the internalcombustion engine will be more appropriate than

the electric machine.

The engine only operation state is entered when

the vehicle speed is greater than the EV only

speed limit or during hard acceleration by the

driver. During this state the power required by

the engine is equal to the vehicle power demand

and the power required by the electric

motor/generator is 0 kW.


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The engine with motor assist state is entered

when the vehicle power demand is greater than

the maximum engine power allowed. During

this state the power required by the engine is

equal to the maximum engine power allowed

and the power required by the electricmotor/generator is the remaining difference

between the vehicle power demand and the

maximum engine power. For example, if the

maximum allowed engine power is 26 kW and

the vehicle power demand is 30 kW, 4 kW will

be supplied by the electric motor, provided the

battery SoC is higher than lower SoC limit.

The engine running and battery charging

operating mode is entered when the current

battery SoC is less than or equal to the lower

SoC limit and vehicle power demand is less than

the maximum engine power allowed. For

example, if the vehicle power demand is 15 kW,

the engine has another 11 kW spare at 3500 rpm.

This 11 kW can be used to run the generator to

charge the battery. This function allows

increasing the load on engine to achieve a better

BSFC as well as charging the battery.

The engine load levelling state is entered when

the battery is at optimum charge but there is

excess torque available from the engine. In this

instance the engine is loaded by controlling the

CVT gear ratio. This allows the Axon60 to run

the engine in a more optimum operating region.

The regenerative braking state is entered when

the vehicle power demand is negative. In light

braking situations, regenerative braking will be

used. The regular friction brake is retained for

harsher braking events. After the batteries are

charged back up to maximum SoC, regenerative

braking would no longer be used. In this

situation, friction brakes would allow the driver

to achieve the required deceleration. In the case

of emergency braking, both regenerative and

conventional braking would occur, giving

maximum braking power. Otherwise only

regenerative braking would be in operation, as

long as the battery pack is not fully charged.

To maximise the use of grid energy, the vehicles

control strategy is developed to have a Charge

Depletion strategy (depending on battery SoC)

followed by a Charge Sustaining strategy.

5. Controller validation andsimulation results

Before implementing the control strategy in the

prototype vehicle, testing of the control strategy

was done using simulation methods. The

complete PHEV model was developed using

WARPSTAR and was used for simulation

testing.

5.1. Performance SimulationFrom the simulation, the power required from

the engine or motor for low speed acceleration

was estimated. The Axon60 vehicle is capable of

reaching 0-30 mph in under 6 seconds and can

reach a maximum speed of 85 mph. Figure 12

shows the power requirements of the Axonvehicle for different acceleration patterns.

Figure 12: Axon60 acceleration performance

5.2. Fuel economy predictionsThe PHEV model developed in WARPSTAR

was simulated to calculate the fuel consumption

figures for the Axon60 vehicle when using only

the ICE for propulsive power. Based on the

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Speed (mph)

Powerrequired(kW)

Power required for acceleration from 0-30mph

5secs

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preliminary control strategy, the Axon60 vehicle

is capable of delivering 107mpg (UK) over the

NEDC without regenerative braking. Figure 13

shows the fuel efficiency figures for three

different technology scenarios.

Figure 13: Axon60 fuel economy figures

5.3. Range testingOne of the important performance requirements

of the Axon60 PHEV is to meet the 10 mile all

electric range. A simulation was carried out for

the ARTEMIS Urban cycle to simulate the real

world usage of a PHEV. From the simulation,

the Axon60 PHEV with a 2 kWh Lithium-Ion

battery pack and 12 kW induction motor when

operated under 35 mph would meet the 10mile

AER.

Figure 14 shows the operation of the vehicle

over the ARTEMIS urban drive cycle where the

vehicle initially operates as an EV.

Figure 14: Axon60 range testing

Once the battery SoC falls below the minimum

threshold, the main propulsive force is provided

by the internal combustion engine.

5.4. Energy consumptionOver the NEDC urban section, the Axon60

vehicle consumes 110 Wh/mile when operating

in electric only mode, whereas on the ARTEMIS

urban cycle, the energy consumption is 181

Wh/mile. When operated as conventional vehicle,

i.e. engine only, the energy required is 316

Wh/mile and 494 Wh/mile respectively.

5.5. Subsystem operation mode testingThe SCU control strategy is designed to control

the CVT ratio to enable the engine operate in the

optimum operating range (shown in red circles).

The simulation results in figure 15 show that the

engine is operating in its most efficient regions.

Figure 15: Axon60 engine operating points

Also, the control strategy for Axon60 PHEV is

designed for a Charge Depleting strategy

followed by Charge Sustaining.

Figure 16 shows that the engine is in idle mode

during the all electric operation and switches on

as soon as the battery SoC falls below 0.2.

Depending on the starting coolant temperature

and battery SoC, the control strategy operates

the engine either in Offmode or in idle mode.

97

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Figure 16: Axon60 engine operation in ARTEMIS

Urban

5.6. Battery management testingTo confirm whether the Axon60 vehicle is

capable of holding the battery SoC at a specified

level (Charge Sustaining strategy), a test was

carried out by repeatedly operating the vehicle in

the NEDC & ARTEMIS urban cycles. Figures

18 & 19 show how the battery SoC decreases

with range and finally reaches the lower SoC

limit of 0.2. At this stage the SCU sustains the

battery SoC and switches on the ICE.

Figure 17: Battery SoC variation in repeated NEDC

Figure 18: Battery SoC variation in ARTEMIS urban

5.7. CO2 analysisUnlike conventional hybrids, a plug-in hybrid

vehicle sources part of its energy from the

electricity grid. To achieve comparative emission

figures, WARPSTAR was extended to include

the carbon emissions from the UK electricity

grid to calculate the Well-to-Wheel (WTW)

emission figures.

Over both the NEDC urban and ARTEMIS

urban cycles, the Axon60 is predicted to have a

WTW CO2 emission less than 50 g/km (assumes

410g/kWh CO2 from UK electricity grid) [8].

This low level of emissions saves approx 1.1

tonnes of CO2 per annum for an average UK car

user when compared to conventional gasoline

cars. Table 3 shows the CO2 emissions for the

three different operating modes of the Axon60vehicle.

Table 3 : Axon60 CO2 emission figures

Drive Cycle Tailpipe

emissions

(g/km)

Wellto-Wheel

emissions

(g/km)

NEDC Urban 0 27

ARTEMIS

Urban

0 46

NEDC

(urbanEV

Extra urbanICE)

41 54

6. Prototype vehicle developmentThe Axon60 prototype vehicle in figure 20 is

undergoing further development and is expected

to complete first phase of testing by the end of

Q4 2010. The first phase of the testing will

involve crash testing the vehicle to European

Union standards and fuel economy assessments.

Figure 19: Axon60 PHEV prototype vehicle

The second stage of the testing involves

reliability and driveability assessments. The

vehicle will be used to gather important real

world data including: battery charge/discharge

characteristics, battery state of charge depletion

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and to validate WARPSTAR predictions. Along

with the technical developments user feedback

will be collected from customers to understand

user perception of plug-in hybrid vehicles. The

demonstrator vehicle will also be used to assess

the practicality of the electric charginginfrastructure being setup across various cities in

the UK. The results of the second phase of

testing and user feedbacks will be presented in a

future paper.

7. ConclusionIn this paper, the experiences gained during the

development of a PHEV demonstrator for the

UK market were presented. The Axon60 project

shows that considerable fuel savings and

emission reduction is possible if vehicles are

made of lightweight materials and combined

with highly efficient drivetrains. The paper also

shares the experience gained in developing the

vehicle supervisory control, component selection

and validation of control strategy for a light

weight PHEV.

8. AcknowledgementsThe authors acknowledge the support provided

by the UK Technology Strategy Board via their

Low Carbon Vehicle Innovation Platform.

9. References[1]. A.Adonis, Low Carbon Transport: A Greener

Future,Department for Transport UK, July

2009, p23

[2]. Cenex, Investigation into the Scope for theTransport Sector to Switch to Electric Vehicles

and Plug-in Hybrid Vehicles, Department for

Transport UK, 2008

[3]. H.T.Bradley, A.A.Frank, Design,demonstrations and sustainability impact

assessments for plug-in hybrid electric vehicles,

Renewable and Sustainable Energy Reviews,

Volume 13, Issue 1, January 2009, Pages 115-128

[4]. G.Muraleedharakurup, A.McGordon, J.Poxon,P.Jennings, "Building a Better Business Case: the

Use of Non-linear Growth Models for Predicting

the Market for Hybrid Vehicles in the UK",Ecologic Vehicles and Renewable Energies

Conference, Monaco, 2010

[5]. http://www.dft.gov.uk/adobepdf/163944/ulcc.pdfaccessed on 11th August 2010 (5k grant link)

[6]. P.Haan, M.Keller, M.Andre,Real-world drivingcycles for emission measurements: ARTEMIS

and Swiss cycles, Bundesamt fr Umwelt, Wald

und Landschaft (BUWAL), 2001

[7]. A.Walker, A.McGordon, G.Hannis, A.Picarelli,J.Breddy, S.Carter, A.Vinsome, P.Jennings,

M.Dempsey, M.Willows, A Novel Structure for

Comprehensive HEV Powertrain Modelling",

2006 Vehicle Powertrain and Propulsion

Conference, 2006

[8]. http://www.decc.gov.uk/en/content/cms/statistics/fuel_mix/fuel_mix.aspx accessed on 18th August

2010.


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10.AuthorsMr. Girish

Muraleedharakurup

Lead Engineer

WMG, University of Warwick,Coventry, CV4 7AL, UK

Email: [email protected]

Dr.John Poxon

Research Fellow



Email: [email protected]

Dr.Andrew McGordon

Sr.Research Fellow



Email : [email protected]

Prof.Paul Jennings

WMG, University of Warwick,Coventry, CV4 7AL, UK


Dr.Steven Cousins

Managing Director

Axon Automotive

Wellingborough,

NN29 7RL, UK


Dr.Kevin Lindsey

Engineering Director

Axon Automotive

Wellingborough,

NN29 7RL, UK


development of a lightweight plug-in hybrid electric vehicle demonstrator

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