SeriesHybridFinal

AUTOMOTIVE ENGINEERING FOR SUSTAINABLE MOBILITY MASTER PROGRAM
Optimization of Fuel
Consumption for a Series
Electric Hybrid Vehicle
Master [M1]
Kadur Vishnuvenkat
Email: vishnuvenkat.kadur@etu.univ-orleans.fr
Kamaraj Thiyagarajan
Email: thiyagarajan.kamaraj@etu.univ-orleans.fr
Karanam Saketh
Email: saketh.karanam@etu.univ-orleans.fr
Luévano Lozano Mauricio
Email: mauricio.luevano-lozano@etu.univ-orleans.fr
01/06/2016
Under the guidance of
Professor Higelin Pascal
Ecole Polytechnique de l'Université d'Orléans
Polytech Orléans, 8 rue Léonard de Vinci, 45072 Orléans cedex 2
Technical Report Number: SeriesHybridFinal.pdf
Abstract: Optimize the fuel consumption with different strategies controlling the two power sources
that is Internal Combustion Engine-Generator and Lithium-Ion battery over the NEDC cycle.
Keywords: NEDC, Coast-Down Test.

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1 Table of Contents
1 Table of Contents.................................................................................................................. ii
2 Table of Figures.....................................................................................................................vi
3 Acknowledgment .................................................................................................................. 1
4 Objective ............................................................................................................................... 2
5 Introduction to Hybrid Vehicles ............................................................................................ 3
5.1 What is Series Hybrid? .................................................................................................. 4
6 System Architecture.............................................................................................................. 5
6.1 Energy Flow Model........................................................................................................ 5
6.2 Calculated Energy Flow Model...................................................................................... 6
6.3 Forward model.............................................................................................................. 7
6.4 Backwards model necessity .......................................................................................... 7
7 Organization (Work split)...................................................................................................... 8
7.1 Vishnuvenkat................................................................................................................. 8
7.2 Thiyagarajan.................................................................................................................. 8
7.3 Saketh............................................................................................................................ 8
7.4 Mauricio ........................................................................................................................ 9
8 State Machine ..................................................................................................................... 10
8.1 Vehicle State Machine States...................................................................................... 10
8.1.1 Vehicle IDLE......................................................................................................... 10
8.1.2 Vehicle IDLE_ICE.................................................................................................. 11
8.1.3 Vehicle EM_ONLY_BATT...................................................................................... 11
8.1.4 Vehicle ICE_GEN.................................................................................................. 11
8.1.5 Vehicle BATT_ICE_EM ......................................................................................... 12
8.1.6 Vehicle BRK.......................................................................................................... 12
9 Electrical Machine............................................................................................................... 13
9.1 Advantages of HUB motors......................................................................................... 13
9.2 Disadvantages ............................................................................................................. 13
9.3 Different types of Electric motors commonly used in Hybrid vehicles....................... 14
9.4 Advantages of PMSM.................................................................................................. 14
9.5 Vehicle Dynamics ........................................................................................................ 15
9.5.1 Estimation of Vehicle mass ................................................................................. 17
9.5.2 Estimation of Wheel Radius ................................................................................ 18
9.5.3 Assumptions made for estimating resistive forces ............................................. 18
9.6 Coast down Test.......................................................................................................... 20
9.6.1 Coast-Down Test result....................................................................................... 20
9.7 Electrical Machine Modelling...................................................................................... 24

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9.8 Optimizing the operating points of electric motor to get the best efficiency by changing
the gear ratio........................................................................................................................... 25
9.9 Final Result.................................................................................................................. 28
9.9.1 Requested Current [A] from each electric motor ............................................... 28
10 Power Electronics............................................................................................................ 29
10.1 Power Electronics Generator and Battery (Converters) ............................................. 29
10.2 Classification of converters......................................................................................... 29
10.3 Rectifier ....................................................................................................................... 30
10.4 Inverter........................................................................................................................ 31
10.5 Power Electronics split-up (MODES)........................................................................... 32
10.5.1 𝑬𝑴𝑷𝒐𝒘𝒆𝒓>𝑮𝑬𝑵𝑷𝒐𝒘𝒆𝒓[110.43A] ................................................................... 32
10.5.2 𝑬𝑴𝑷𝒐𝒘𝒆𝒓>𝑩𝑨𝑻𝑻𝑷𝒐𝒘𝒆𝒓&& < 𝑮𝑬𝑵𝑷𝒐𝒘𝒆𝒓[90 - 110.43A]........................... 32
10.5.3 𝑬𝑴𝑷𝒐𝒘𝒆𝒓<𝑩𝑨𝑻𝑻𝑷𝒐𝒘𝒆𝒓 [< 90A] .................................................................... 33
10.5.4 𝑬𝑴𝑹𝒆𝒈𝑷𝒐𝒘𝒆𝒓 .................................................................................................. 33
11 Battery............................................................................................................................. 34
11.1 Main Battery Types ..................................................................................................... 34
11.2 Selection of hybrid battery.......................................................................................... 34
11.2.1 Comparison of battery types............................................................................... 34
11.2.2 List of top batteries used by top hybrid car manufacturers ............................... 35
11.2.3 Comparison between different batteries............................................................ 35
11.3 Literature review [4] [5] .............................................................................................. 36
11.3.1 Hybrid car batteries............................................................................................. 36
11.3.2 Lead acid batteries .............................................................................................. 36
11.3.3 Nickel metal hydride ........................................................................................... 37
11.3.4 Honda’s Choice on NiMH .................................................................................... 37
11.3.5 Lithium-ion batteries........................................................................................... 37
11.4 Battery parameters ..................................................................................................... 38
11.5 Methods for selection – battery pack......................................................................... 39
11.5.1 Main classification of lithium-ion battery ........................................................... 39
11.5.2 Justification ......................................................................................................... 40
11.6 Hybrid Battery Sizing................................................................................................... 41
11.6.1 Battery cell sizing technique ............................................................................... 41
11.6.2 Literature review................................................................................................. 41
11.6.3 Determination of battery pack assembly............................................................ 43
11.6.4 Sizing a cell .......................................................................................................... 43
11.7 Hybrid battery modeling & simulation........................................................................ 44
11.7.1 Objective ............................................................................................................. 44

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11.7.2 Battery block ....................................................................................................... 44
11.7.3 State of charge .................................................................................................... 45
11.7.4 Internal Resistance.............................................................................................. 45
11.7.5 Energy.................................................................................................................. 45
11.7.6 Designing a battery ............................................................................................. 46
11.7.7 Basic battery model............................................................................................. 46
11.8 Modelling a battery..................................................................................................... 47
11.8.1 Simulink Library................................................................................................... 47
11.8.2 Simulink model of the battery............................................................................. 49
11.8.3 Charging and discharging characteristics............................................................ 50
11.8.4 Global Efficiency over the Driving cycle.............................................................. 50
12 Generator........................................................................................................................ 52
12.1 Terminology ................................................................................................................ 52
12.2 General representation............................................................................................... 52
12.3 Selection...................................................................................................................... 53
12.3.1 Benefits................................................................................................................ 53
12.4 Specifications .............................................................................................................. 53
12.5 Efficiency Maps ........................................................................................................... 54
12.6 Simulink Model............................................................................................................ 55
12.7 Visio Model.................................................................................................................. 55
13 ICE + Fuel......................................................................................................................... 56
13.1 ICE................................................................................................................................ 56
13.2 Fuel.............................................................................................................................. 58
13.3 ICE + Fuel Integration.................................................................................................. 59
13.3.1 Fuel Mass Flow Rate............................................................................................ 59
13.3.2 Volume ................................................................................................................ 59
14 Supervisor........................................................................................................................ 60
14.1 Main objectives........................................................................................................... 60
14.2 Supervisor Block.......................................................................................................... 60
14.3 Vehicle Modes Description ......................................................................................... 61
14.3.1 Battery Limit Block .............................................................................................. 62
14.3.2 Power Split Block................................................................................................. 64
14.3.3 Positive Power Split Block ................................................................................... 66
14.3.4 Memory Block ..................................................................................................... 68
14.3.5 Conditions Block.................................................................................................. 69
14.3.6 Supervisor Integrated Model .............................................................................. 70
14.4 Model Integration ....................................................................................................... 71
14.4.1 Supervisor and ICE............................................................................................... 71

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14.4.2 ICE coupled with Generator ................................................................................ 72
14.4.3 Power Electronics coupled Supervisor................................................................ 73
15 Results............................................................................................................................. 74
15.1 First Strategy ............................................................................................................... 74
15.1.1 Preliminary Results.............................................................................................. 74
15.2 Optimized Strategy...................................................................................................... 75
15.2.1 Final Results......................................................................................................... 76
16 Assumptions and Limitations.......................................................................................... 78
17 Conclusions ..................................................................................................................... 78
18 Project Management....................................................................................................... 79
18.1 Gantt chart .................................................................................................................. 79
18.2 Meeting Sessions Reports........................................................................................... 80
18.3 Storage Management.................................................................................................. 81
19 Appendix ......................................................................................................................... 82
19.1 Proposed Sensors........................................................................................................ 82
19.1.1 Radar Speed Gun................................................................................................. 82
19.1.2 Delta DRS100 Non-Contact Sensor ..................................................................... 83
19.1.3 DotZ1 Pro DMI (Distance Measuring Instrument) .............................................. 85
19.1.4 Hall Effect Sensor ................................................................................................ 86
19.1.5 Variable Reluctance Speed Sensor...................................................................... 87
19.2 Selected Sensors.......................................................................................................... 88
19.2.1 GPS ...................................................................................................................... 88
19.2.2 Speed Sensor....................................................................................................... 91
19.2.3 Accelerometer..................................................................................................... 92
20 Arrangement ................................................................................................................... 93
20.1 Hardware Pinout ......................................................................................................... 93
20.2 Software...................................................................................................................... 93
20.3 Post- Processing Data.................................................................................................. 95
20.3.1 Hall Effect Sensor ................................................................................................ 95
20.3.2 Post Processing (GPS).......................................................................................... 96
20.4 Poster .......................................................................................................................... 98
21 References....................................................................................................................... 99

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2 Table of Figures
Figure 1 Block Layout of Series Hybrid.......................................................................................... 4
Figure 2 High Level vehicle model................................................................................................. 6
Figure 3 Vehicle State Machine States........................................................................................ 10
Figure 4 Comparison between Different electric motors used for automotive application ...... 14
Figure 5 NEDC.............................................................................................................................. 15
Figure 6 Vehicle Dynamics (Simulink Model).............................................................................. 19
Figure 7 Resistive forces acting on the vehicle at different speeds and road conditions were
calculated .................................................................................................................................... 20
Figure 8 Vehicle Dynamics after Coast down Test (Simulink Model).......................................... 21
Figure 9 Requested Torque on Wheels (First Result).................................................................. 22
Figure 10 Requested Torque on Wheels after Coast-Down Test................................................ 22
Figure 11 Requested Power on wheels....................................................................................... 23
Figure 12 Efficiency Map - Electric Motor................................................................................... 24
Figure 13 Electric Motor (Simulink Model) ................................................................................. 24
Figure 14 Electric Motor - Operating Points ............................................................................... 25
Figure 15 Electric Motor efficiency with different gear ratios.................................................... 25
Figure 16 Electric Motor efficiency with 2.5 gear ratio............................................................... 26
Figure 17 Electric Motor - Operating Points with 2.5 gear ratio................................................. 26
Figure 18 Model Integration NEDC - Vehicle Dynamics - Electric Motor.................................... 27
Figure 19 Requested current from one electric motor............................................................... 28
Figure 20 Rectifier ....................................................................................................................... 30
Figure 21 Inverter Block .............................................................................................................. 31
Figure 22 Current limits of different components along NEDC .................................................. 32
Figure 23 Comparison of different chemistries for the batteries of Li-ion................................. 39
Figure 26 Battery block ............................................................................................................... 44
Figure 27 Voltage vs State of Charge .......................................................................................... 46
Figure 28 Simulink library for Battery components.................................................................... 47
Figure 29 Relay Mechanism ........................................................................................................ 48
Figure 30 Simulink model of the battery..................................................................................... 49
Figure 31 Charging and Discharging Characteristics of the battery............................................ 50
Figure 32 Simulink model to determine the global efficiency of the battery............................. 51
Figure 33 General representation of Generation ....................................................................... 52
Figure 34 Generator Efficiency Map ........................................................................................... 54
Figure 35 Simulink Generator Model.......................................................................................... 55
Figure 36 Visio Generator Model................................................................................................ 55
Figure 37 ICE Block...................................................................................................................... 56
Figure 38 ICE Efficiency Map....................................................................................................... 57
Figure 39 ICE + Fuel (Simulink Model)......................................................................................... 59
Figure 40 Supervisor - Battery Limit Block .................................................................................. 62
Figure 41 Supervisor - Battery Limit Block (Simulink Model)...................................................... 62
Figure 42 Supervisor - Battery Limit Block (Simulink Model Test).............................................. 63
Figure 43 Supervisor - Power Split Block..................................................................................... 64
Figure 44 Supervisor - Power Split Block (Simulink Model) ........................................................ 64
Figure 45 Supervisor - Power Split Block (Simulink Model Test) ................................................ 65
Figure 46 Supervisor – Positive power split................................................................................ 66
Figure 47 Supervisor – Positive Power split (Simulink Model).................................................... 66
Figure 48 Supervisor – Positive Power split (Simulink Model Test)............................................ 67
Figure 49 Supervisor - Memory state block ................................................................................ 68
Figure 50 Supervisor - Memory Block (Simulink Model)............................................................. 68
Figure 51 Supervisor - Block Conditions...................................................................................... 69

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Figure 52 Supervisor - Block Conditions (Simulink Model) ......................................................... 69
Figure 53 Supervisor - Integrated Block...................................................................................... 70
Figure 54 Supervisor - Integrated Block (Simulink model).......................................................... 70
Figure 55 Integration ICE - Supervisor (Global Simulink Model)................................................. 71
Figure 56 Integration Gear Reduction ICE - Generator (Global Simulink Model)....................... 72
Figure 57 Integration Supervisor - Power Electronics (Global Simulink Model)......................... 73
Figure 58 Power electronics Block (Simulink Model).................................................................. 73
Figure 59 Results - SOC along NEDC cycle while varying the minimum SOC .............................. 74
Figure 60 Results - Fuel consumption along NEDC cycle while varying the minimum SOC........ 74
Figure 61 Strategy – Optimized Implemented Strategy.............................................................. 75
Figure 62 Strategy – Optimized Implemented Strategy (Zoom) ................................................. 75
Figure 63 Results - SOC along NEDC cycle while varying the initial SOC..................................... 76
Figure 64 Results - Fuel Consumption along NEDC cycle while varying the initial SOC.............. 76
Figure 65 Results - SOC along NEDC cycle while varying the minimum SOC .............................. 77
Figure 66 Results - Fuel Consumption along NEDC cycle while varying the minimum SOC ....... 77
Figure 67 Series hybrid Gantt chart ............................................................................................ 79
Figure 68 Template for Series hybrid meetings .......................................................................... 80
Figure 69 Series Hybrid Storage Management ........................................................................... 81
Figure 70 Radar Speed Gun......................................................................................................... 82
Figure 71 Radar Speed Gun......................................................................................................... 82
Figure 72 Delta DRS100 Non-Contact Sensor ............................................................................. 83
Figure 73 Delta DRS100 Non-Contact Sensor ............................................................................. 83
Figure 74 DotZ1 Pro DMI (Distance Measuring Instrument) ...................................................... 85
Figure 75 Hall Effect sensor by Littlefuse.................................................................................... 86
Figure 76 Application Example (Geartooth Sensor).................................................................... 86
Figure 77 Variable Reluctance Speed Sensor.............................................................................. 87
Figure 78 Reluctor ring on the CV joint....................................................................................... 87
Figure 79 Selected Sensor – GPS Adafruit Industries 746........................................................... 88
Figure 80 Selected Component - GPS Antenna........................................................................... 89
Figure 81 Selected Component - Antenna to GPS Connector..................................................... 89
Figure 82 Selected Component - Antenna Connector ................................................................ 90
Figure 83 Selected Component - Acquisition System Enclosure................................................. 90
Figure 84 Selected Sensor - Cherry Speed Sensor....................................................................... 91
Figure 85 Selected Sensor - FLORA Accelerometer Adafruit Industries 1247............................. 92
Figure 86 Arduino UNO Pinout with the selected sensors.......................................................... 93
Figure 87 Hall Effect Sensor ........................................................................................................ 95
Figure 88 Simulink model to retrieve the speed......................................................................... 95
Figure 89 GPS .............................................................................................................................. 96
Figure 90 GPS with Antenna cord ............................................................................................... 97
Figure 91 Coast down path plot.................................................................................................. 97
Figure 92 Deliverables - Final SIA Conference Poster ................................................................. 98

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3 Acknowledgment
We would like to extend our sincere thankfulness to all the professors for having given
us an opportunity to make use of the facilities available all around the University
campus.
Our special thanks to Madame Mongella who helped us communicate between various
professors, also in ordering of several goods and products.
At the outset we would like to thank Prof. Pascal Higelin for having created this
opportunity and encouraged us throughout. Thank you for your guidance throughout
the project.
Last and definitely the most important, thanks to our friends for their unconditional
support, patience and tolerance.

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4 Objective
Optimize the fuel consumption with different strategies controlling the two power
sources that is Internal Combustion Engine-Generator and Lithium-Ion battery over the
NEDC cycle.
To achieve this goal:
 Individual modelling was carried out for each component and further block
integration was done to achieve the following results.
 Measurements of losses and engine efficiency were performed.
 Other components specifications were taken from literature and technical
documentation.

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5 Introduction to Hybrid Vehicles
Hybrid electric vehicle (HEV) is a type of hybrid vehicle that combines a conventional
internal combustion engine (ICE) propulsion system with an electric propulsion system
(hybrid vehicle drivetrain). The presence of the electric powertrain is intended to
achieve either better fuel consumption than a conventional vehicle or better
performance. The hybrids are available in various types and degree to which they
function as electric vehicle (EV). The most common form of hybrid electric vehicle (HEV)
is the hybrid electric car, although which hybrid electric buses, trucks also exist.
The present generation hybrid electric vehicle make use of the efficiency improving
technologies such as regenerative braking, which converts the vehicle’s kinetic energy
into electric energy to charge the battery, instead of wasting it as heat energy as
conventional brakes do.
There are few hybrid electric vehicles where the internal combustion engine (ICE) is used
to generate electricity by operating the generator, to either directly power the electric
drive motors or charge the batteries directly.
Many HEV’s reduce idle emissions by shutting off the ICE when idle and restarting it
when needed, this concept being known as the start-stop system. The hybrid electric
produces fewer emissions from the ICE than the one on a conventional car, the reason
being the ICE in a HEV are comparatively smaller than the one seen on a conventional
car.
Hybrid vehicle are the vehicle with one or the combination of the points below:
 Multiple forms of motive power – at least two
 Multiple sources of energy – at least two
Hybrids come in many configurations. For example, a hybrid vehicle may receive all its
energy from on-board petroleum fuel, however maybe driven by an electric motor or a
combustion engine at various times or both together. [1]
Types of Hybrids:
 Series Hybrids
 Parallel Hybrids
 Power split (Series – Parallel) Hybrids
In parallel hybrids, the electric motor and the ICE are both connected to the mechanical
transmission and can simultaneously transmit power to drive the wheels.
In series hybrids, only the electric motor drives the drivetrain and the smaller ICE works
as a generator to power the electric motor or to recharge the battery.
In series – parallel hybrids, the combination of series and parallel system is used. As a
result they are more efficient overall because series hybrids are more efficient at lower
speeds and parallel hybrids are more efficient at high speeds, but however the cost of
power split hybrids are way higher compared to the pure hybrids. [1]
Types of degree of hybridization:
 Full hybrid – This is also called strong hybrid. These are vehicles which can run
just on the engine, just the battery or the combination of both.

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 Mild hybrid – These are vehicles that cannot be drive solely on its electric
motor because the electric motor does not have enough power to proper the
vehicle on its own.
 Plug-In hybrid – These are vehicles that used rechargeable batteries or another
storage device, that can be recharged by plugging it in to an external source of
electric power.
 Micro hybrid – These hybrids are considered by some as barely even a hybrid. It
uses start-stop and often may include a 48-volt battery to operate on board
electrical system and may improve the economy by 10-20 percent.
5.1 What is Series Hybrid?
Figure 1 Block Layout of Series Hybrid
Series hybrids are the types of hybrids where electric machine is the main source of
power to run the vehicle and internal combustion engine is used as a range extender. In
series hybrids, the entire mechanical transmission between the ICE and the wheel is
removed and replaced by an electric generator and electric traction motors with the
benefit the ICE is no longer directly connected to driving wheels.
The electric traction system and the combustion engine generator operate
independently of each other with each operating at its most efficient range. This has
many advantage, a smaller generator/engine can be fitted as compared to the size of a
conventional direct drive engine. Electric traction motors can retrieve electricity from
the buffer energy store, the electric battery or directly from the engine/generator or
both. This improves the load balancing with traction motors frequently being powered
only by the electric battery bank which may be charged from external sources such as
the electricity grid. [6]

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6 System Architecture
The following two figures represent the power flow and the backwards (calculated
energy) model of the system architecture.
6.1 Energy Flow Model
Figure 2 Energy Flow Model
Figure 2 represents the flow of energy in the system. The flow of energy starts from
the right to the left as represented by orange arrows. The fuel block consists of fuel
which is injected into the ICE to obtain power from the ICE. This in-turn runs the
generator. The generator converts the mechanical power into electrical power. The
electrical power is used in two modes:
1.To run the electrical machine
2. To charge the battery from the excess power generated
the battery up next has an initial state of charge (SOC), this supplied the power to the
electric machine to run it. When the state of charge is below the minimum it receives
power from the generator or from the electric machine which acts as a generator
during regenerative braking.
The power electronics split the power between the battery and the generator. They
act as the medium between these two devices to receive and convert power as
required. These operations are performed by the commands of the supervisor. The
electric machine receives the power from either generator or battery to complete the
NEDC cycle.

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6.2 Calculated Energy Flow Model
Figure 3 Calculated Energy Flow Model
Figure 3 is the representation of the calculated energy flow. We can see that the NEDC
(New European Driving Cycle) is the input to the system. The NEDC graph represents
the speed vs time [Km/h] curve. The NEDC is converted to speed vs time [m/s].
Differentiating this, acceleration is obtained [m/s^2]. From the various aerodynamics,
forces are calculated which are added to the total force [N]. This force is further
multiplied by the wheel radius [m] to obtain the requested torque in Nm. Using the
input as torque [Nm] and speed [rad/s], with the help of the efficiency maps of the
electric motor, the requested current is obtained. This requested current is controlled
by the supervisor which is the brain of the entire system. Based on the requested
current from the electric motor the supervisor decides if the battery or the generator
provides the current.
The generator is coupled to the ICE and this operates as ON/OFF based on the power
request from the electric motor but controlled by the supervisor. The ICE is in-turn
connected to the fuel block to measure the quantity of fuel being used.
The battery which is another source of power is connected to the power electronics
operated by the supervisor. It provides power based on the power request from the
motor. The supervisor decides if the battery is used to deliver power or used to store
excess power.
At the highest level, the vehicle model is represented by:
Figure 2 High Level vehicle model

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6.3 Forward model
It contains the three primary divisions; the driver (NEDC cycle), the hybrid electric
powertrain, and the vehicle. As a general summary, the model feedbacks vehicle
velocity to the driver, who compares it with a desired velocity and responds with an
accelerator or brake pedal position that then actuates the power train and
consequently moves the vehicle. This particular sequence is a representative of a
forward model (with respect to causality).
6.4 Backwards model necessity
Oppositely, a backward model initially considers a desired velocity profile and
subsequently calculates the road load which is then completely satisfied through a
combination of power train actuator torque output as dictated by control strategy.
Thus a backward model exactly follows the desired driving cycle while forward model
attempts to as closely as possible.
Forward model more precisely represents real world driving and thus is the
appropriate choice in conjunction with development of a control strategy.
We began with the backwards model because it was convenient for sizing of the
components.

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7 Organization (Work split)
7.1 Vishnuvenkat
 Vehicle Dynamics
o Estimation of Resistive Forces
o Estimation of Torque Request on Wheels
o Calculation of Torque request based on Coast down test results
o Sizing of Electric motor based on Power request
 Electric Motor
o Selection of electric motor
o Electric motor modelling
o Calculation of required current
 Optimizing the operating points of electric motor to get the best efficiency by changing
the gear ratio
 Coast down test
o Proposal of variable reluctance speed sensor for speed measurement.
 Strategy
 Electric motor and battery model integration
 Battery efficiency
7.2 Thiyagarajan
 Battery
o Hybrid Battery Selection
o Sizing of the battery based on the Power requirement from Electric Motor
o Hybrid Battery modelling in Matlab/Simulink
o Integration of Battery to Electric Motor and Generator and Global model Assembly
o Determining the global efficiency of the battery over the NEDC driving cycle
 Invertor
o Literature study and power converters (to step up/down the voltage) is assumed to
be 80%.
 Coast-Down Test
o Proposed a Hall Effect sensor for determining the vehicle speed during coast down
test
 Post Processing
o Retrieving data from the coast down test
 Coding in Matlab
o Determining the speed of the vehicle further to determine the acceleration for the
calculation of the Resistive forces
 NEDC Optimization Strategy
7.3 Saketh
 System Architecture
 Component Modelling
o Generator
o Power Electronics
 Integration of components

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o ICE : Generator
o Generator : Battery
o Power Electronics
 Coast down test
o Sensor proposed
o Post processing
7.4 Mauricio
• Block Modelling
o ICE
o Fuel
o Supervisor
• Model Integration
o Fuel Block – ICE Block – Supervisor Block – Power Electronics Block
• Coast Down Test
o Component Selection
o Software development and software testing

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8 State Machine
8.1 Vehicle State Machine States
Figure 3 Vehicle State Machine States
[1] IDLE: The vehicle is not moving.
[2] IDLE & ICE: The ICE is switched on and power from generator is used to charge the battery.
[3] BATTERY: The power from the battery is supplied to electric motor.
[4] BRAKING: The electric motor runs as generator to charge the battery.
[5] ICE & GENERATOR: The power from the ICE & GENERATOR is supplied to electric motor.
[6] BATTERY + ICE & GENERATOR: The combined power is supplied to electric motor as power
request is higher than the individual power outputs.
8.1.1 Vehicle IDLE
Vehicle IDLE state describes the behavior when the vehicle is not moving; this
means the internal combustion engine (ICE) and therefore the generator and electric
motor (EM) rest inactively.
Battery package is not being charged by generator or regenerative braking or
discharged by an electric motor request.
IDLE state will be the initial state of our model, and it will stay until a Power
request is received from the NEDC cycle (acceleration request).

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If this power request is lower or equal than the battery power, vehicle state will transit
to EM_ONLY_BATT state.
If this power request is greater than the battery power, vehicle state will transit to
BATT_ICE_EM state, actually this state will never be attained because it will describe a
very high acceleration and NEDC is well known for its smooth accelerations.
8.1.2 Vehicle IDLE_ICE
Vehicle IDLE_ICE state describes the behavior when the vehicle is charging the
battery package while not moving; this means the internal combustion engine (ICE) and
therefore the generator are on. But the electric motor (EM) rest inactively.
Battery package is being charged by generator.
IDLE_ICE state happens when the battery package state of charge (SOC) depletes
too low (below the minimum state of charge battery value) or when requested by the
Implemented strategy.
Vehicle will remain in IDLE_ICE state until:
1. Battery Package State of charge (SOC) reaches the maximum state of charge
battery package value. In this case vehicle state will transit to IDLE state.
2. A power request is received from the NEDC cycle (acceleration request), in this
case vehicle state will transit to ICE_GEN state. Since we have a condition to use
the battery package until it reaches the maximum state of charge.
8.1.3 Vehicle EM_ONLY_BATT
At the vehicle EM_ONLY_BATT state the vehicle launches from rest via the tractive
electric machine (as a motor) and operates only with current supplied by battery package. At
this state the internal combustion engine (ICE) and the generator rest inactively.
The EM_ONLY_BATT state will only accelerate the vehicle in this mode.
Three conditions exist at which point the vehicle leaves the EM_ONLY_BATT state:
1. If a braking request is received from the NEDC cycle (deceleration request)
indicating a desire of slowing down the vehicle. In this case vehicle state will
transit to REGEN_BRK state.
2. If a power request is received from the NEDC cycle (acceleration request)
indicating a desire of power greater than the one provided by battery package.
In this case vehicle state will transit to ICE_GEN state.
3. Battery Package State of charge (SOC) depletes to a level not conducive to
supporting operation of the Electric Motor. In this case vehicle state will transit
to ICE_GEN state.
8.1.4 Vehicle ICE_GEN
At the vehicle ICE_GEN state the vehicle runs via the tractive electric machine
(as a motor) and operates only with current supplied by the generator current. At this
state, the internal combustion engine (ICE) and the generator are both running.

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The ICE_GEN state will accelerate the vehicle through the power provided by
generator.
Three conditions exist at which point the vehicle leaves the ICE_GEN state:
indicating a desire of null power. In this case vehicle state will transit to
REGEN_BRK state.
indicating a desire of power greater than the one provided by battery package.
In this case vehicle state will transit to BATT_ICE_EM state.
indicating a desire of lower power than the one provided by generator. In this
case vehicle state will transit back to EM_ONLY_BATT state.
8.1.5 Vehicle BATT_ICE_EM
At the vehicle BATT_ICE_EM state the vehicle runs via the tractive electric
machine (as a motor) and operates with both current supplied by the generator and
from battery package. At this state, the internal combustion engine (ICE) and the
generator are both running.
The BATT_ICE_EM state will accelerate the vehicle through the power provided
by generator and battery.
Two conditions exist at which point the vehicle leaves the BATT_ICE_EM state:
indicating a desire of null power. In this case vehicle state will transit to
REGEN_BRK state.
indicating a desire of lower power than the one provided by both battery
package and generator. In this case vehicle state will transit to BATT_ICE_GEN
state.
8.1.6 Vehicle BRK
At the vehicle BRK state the vehicle brakes via the tractive electric machine (as a
generator) and if braking power is not enough it will use the mechanical. At this state,
the internal combustion engine (ICE) and therefore the generator rest inactively.
The BRK state will deaccelerates the vehicle through the power provided by the
electrical machine as generator.
Three conditions exist at which point the vehicle leaves the BRK state:
1. If a null request is received from the NEDC cycle (vehicle stop) indicating a
desire of null power. In this case vehicle state will transition to VEH_IDLE state.
indicating a desire of power from battery package. In this case vehicle state will
transit to EM_ONLY_BATT state.

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9 Electrical Machine
As we saw in the system architecture, In a Series hybrid vehicle only the Electric motor
drives the vehicle and they utilize the internal combustion engine as an auxiliary power unit
to extend the driving range of pure electric vehicle. Using a generator, the engine output is
converted into electricity that can either directly feed the motor or charge the battery.
Regenerative braking is possible using the traction motor as a generator and storing the
electricity in the battery.
Electric traction motor is a vital part of the Series hybrid vehicle. Hence, detailed study
had to be done before choosing the right Electric traction Motor.
Firstly we started with some study on various technologies available which were well
suited for a Series Hybrid vehicle without considering the cost of the technology.
We chose to use Wheel HUB motor. The wheel hub motor (also called wheel
motor, wheel hub drive, hub motor or in-wheel motor) is an electric motor that is
incorporated into the hub of a wheel and drives it directly.
We chose this technology mainly due to its various advantages:
9.1 Advantages of HUB motors
 Hub motors negate the need for a heavy transmission, driveline, differential,
and axles. This cuts mechanical losses, inherent in every component standing
between the engine and wheel. It also cuts weight, which makes for more-
efficient travel.
 From a designer’s standpoint, hub motors offer flexibility. They can be used to
power rear or front-wheel drive vehicles, as well as all-wheel-drive versions.
 Their relatively compact size means more room for other components, which
could be a battery pack, fuel cell, or a generator.
 Hub motors can be used as brakes by acting as a generator rather than a motor.
The spinning wheels slow down as they are forced to work against the
electromagnetic fields to create electricity. This regenerative braking also lets
the vehicle create electricity that can be stored and reused later.
9.2 Disadvantages
The major challenge facing hub motors is the issue of unsprung weight. Unsprung
weight is the mass of all components not supported by a car’s suspension Unsprung
weight includes wheels, tires, and brakes, and it tries to follow the contours of the road.
The sprung mass, however, is shielded from most of these movements, especially the
smaller ones, by the suspension. And the sprung weight and suspension act to press
down on the wheels so that they are in contact with the road. This increase in unsprung
mass affects the handling of the vehicle.

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The next step was to select the type of electric motor to be used:
9.3 Different types of Electric motors commonly used in Hybrid
vehicles
• DC motors
• Induction motors
• Permanent magnet synchronous motor
• Switched reluctance motor
• Brushless DC motor
From the above list Permanent magnet synchronous motor is well suited for our
application mainly because:
9.4 Advantages of PMSM
• PMSM provides higher power density for their size compared to electromagnetic
excited motors.
• This aides compactness which is very important for a Hub motor since it is
selected.
• There are no excitation losses providing higher efficiency.
• And also PMSM provides high efficiency with low speeds thus giving all round
efficient operation.
Comparison between Different electric motors used for automotive
application
Figure 4 Comparison between Different electric motors used for automotive application
This is a small comparison study of different parameters for different electric motors
which we got from the research paper, here we can observe that the PMSM scores the
highest in Power Density and Efficiency which are the two main concerns for our project
so based on this various advantages Permanent magnet synchronous motor is selected.

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The next step was the sizing of the components:
9.5 Vehicle Dynamics
For the sizing of the electric motor it is important to know the power required on the
wheels. For this to calculate we have used a backwards approach. That is by using a New
European Driving Cycle [NEDC] as a reference.
In Europe NEDC represents typical usage of passenger cars. This cycle is taken as a
reference for the emission, fuel consumption and electric energy consumption in a
Hybrid vehicle.
Figure 5 NEDC
Table 1 NEDC data
Characteristics Unit ECE-15 EUDC NEDC
Distance m 4*1017=4068 6955.5 11022
Time/Duration s 4*195=780 400 1180
Average Speed m/s 5.21
(with idle)
17.38 9.34
(with idle)
Maximum Speed m/s 13.88 33.3 33.3

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It consists of four repeated ECE-15 urban driving cycles (UDC) and one Extra-Urban
driving cycle (EUDC). The maximum speed in urban cycle is 50km/h and in Extra Urban
cycle is 120km/h.
The combined fuel economy is calculated by a total consumption of urban and extra-
urban cycles over the total distance (theoretical 11022 meters). The total test time
amounts to 1180 s with an average speed of 33.6 km/h
So with the help of this NEDC cycle we now know what the vehicle has to achieve or
follow the speed with respect to time.
So the next step was to determine the forces acted on the vehicle or the forces that
the vehicle has to overcome to follow the NEDC cycle
For estimating the forces acting on the wheels vehicle dynamic equations are
considered:
The propulsion system produces mechanical energy that is assumed to be momentarily
stored in the vehicle. The driving resistances are assumed to drain energy from this
reservoir.
The energy in the vehicle is stored:
• In the form of kinetic energy when the vehicle is accelerated; and
• In the form of potential energy when the vehicle reaches higher altitudes.
Driving 𝑭𝒐𝒓𝒄𝒆 = 𝑉𝑒ℎ𝑖𝑐𝑙𝑒 𝑚𝑎𝑠𝑠 ∗ 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛
LOSSES: Resistive Forces
• Aerodynamic Resistance
Aerodynamic force is exerted on a body by the air (or some other gas) in which
the body is immersed, and is due to the relative motion between the body and
the gas.
𝑭 𝒂𝒆𝒓𝒐 =
𝟏
𝟐
𝝆𝑪 𝑫 𝑽 𝟐
𝑨
• Rolling Resistance
Rolling resistance, sometimes called rolling friction or rolling drag, is the force
resisting the motion when a body (such as a ball, tire, or wheel) rolls on a
surface. It is mainly caused by non-elastic effects
𝑭 𝑹𝑹 = 𝑪 𝑹 ∗ 𝒎 ∗ 𝒈
• Grade Resistance
• The force induced by gravity when driving on a non-horizontal road is
conservative and considerably influences the vehicle behaviour in our case it is
considered to be a flat surface hence it is zero in our case

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𝑭 𝑮𝑹 = 𝒎 ∗ 𝒈 ∗ 𝐬𝐢𝐧 𝜽
Since we are using a backwards approach to know the forces acting on the wheels or to
know the power to be generated by the electric motor to follow the NEDC cycle, resistive
forces has to be added to the Driving force to find out the Total tractive force.
Total Tractive Force = 𝐷𝑟𝑖𝑣𝑖𝑛𝑔𝐹𝑜𝑟𝑐𝑒 + 𝐹𝑎𝑒𝑟𝑜 + 𝐹𝑅𝑅 + 𝐹𝐺𝑅
Once Total tractive force is calculated Torque on the wheels is calculated by multiplying
it with the vehicle wheel radius.
Required Torque on Wheels = 𝑇𝑇𝐹 ∗ 𝑊ℎ𝑒𝑒𝑙 𝑅𝑎𝑑𝑖𝑢𝑠
From the Vehicle dynamics equations we can see that wheel radius and the vehicle
weight are the two important parameters to be considered.
9.5.1 Estimation of Vehicle mass
Table 2 Estimation of Vehicle Mass
mass[KG] mass[KG]
Vehicle[Kerb Weight] 1175
Renault [Engine+Gearbox] -130
SMART Engine 78
Electric Motor[2] 120
Generator 38
Battery 32
Converters 7
Driver 80
Total Weight 1400
Since we are using a SMART Engine in a Renault Clio III vehicle.
 The weight of Renault engine and gearbox is deducted and the weight of SMART
Engine is added.
 The weights of Electric motor and generator are taken from the advisor
software.
 The weight of the battery is calculated according to the sizing of the battery.

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9.5.2 Estimation of Wheel Radius
The wheel radius is got from the specification list
Tyre Specification- 165/65 R15
165 indicates the width of the tyre in mm
65 indicates aspect ratio [height is 65%of its width]
15 nominal diameter of the wheel rim [15 inches]
=165*0.65=107.25=107.25*2=214.5mm8.4448 inches
Diameter of the wheel = wheel rim dia+8.444823.448inches
Radius of the wheel23.448/211.7224inches= 0.2977m
9.5.3 Assumptions made for estimating resistive forces
 Coefficient of RR = 0.012
 Frontal Area = 2.12𝑚2
 Drag coefficient = 0.34
 Density of air = 1.225kg/𝑚3
To Estimate the forces on the wheels a Simulink model is built with the help of the above
mentioned vehicle dynamics equations.

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Figure 6 Vehicle Dynamics (Simulink Model)
 The Requested Torque on the wheels is estimated from the model
 The required acceleration of the vehicle is calculated by derivating the speed.
 Resistive forces are added to the driving force to calculate Total tractive force
 The total tractive force is multiplied by the wheel radius to get the required
torque on wheels

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9.6 Coast down Test
Coast down is one of the most frequent tests for motor vehicles in which the vehicle is
launched from a certain speed with the engine ungeared, simultaneously recording the
speed and travelled distance until vehicle stops. This can be done for different reasons,
mainly targeting to obtain valuable information about the general condition of the
vehicle and about its interaction with the environment
One main aim of this test is to evaluate the values of the resistant forces acting on the vehicle
at certain speed and road conditions
9.6.1 Coast-Down Test result
Aerodynamic Forces + Friction Losses
Figure 7 Resistive forces acting on the vehicle at different speeds and road conditions were calculated
𝑭 = 𝟎. 𝟐𝟗𝟑𝟏𝒗 𝟐
+ 𝟒. 𝟕𝟓𝟒𝒗 + 𝟗𝟗. 𝟖𝟕
The coast down result from the previous year is used to calculate the actual resistive
forces acting on the vehicle.

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Figure 8 Vehicle Dynamics after Coast down Test (Simulink Model)
Here the estimated resistive forces are replaced by the equation which is obtained from
the Coast down Test to calculate the actual torque required on the wheels.
By doing this more detailed study is done since the actual resistances acting on the
vehicle are calculated from the coast down test.
The estimated TORQUE and the actual TORQUE on wheels required is compared.

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9.6.1.1 First Results
9.6.1.1.1 Estimated Torque Request based on assumptions
Figure 9 Requested Torque on Wheels (First Result)
9.6.1.1.2 Torque Request based on Coast Down results
Figure 10 Requested Torque on Wheels after Coast-Down Test
From the above results, there is no much difference between the estimated torque and
the torque based on Coast down results. This proves that the estimated values are
reliable and could be taken into account.
It is observed that the maximum torque required in the cycle is 470 Nm.
0 200 400 600 800 1000 1200
-600
-400
-200
0
200
400
600
Time[s]
Torque[Nm]
Requested Torque[Nm]on Wheels
0 200 400 600 800 1000 1200
-600
-400
-200
0
200
400
600
Time[s]
Torque[Nm]
Requested Torque[Nm]on Wheels

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9.6.1.2 Second Results
9.6.1.2.1 Requested Power on wheels [used for the sizing of Electric motor]
Power =
𝟐∗𝝅∗𝑵∗𝑻
𝟔𝟎
Figure 11 Requested Power on wheels
Once we got the required torque on wheels, required power is calculated.
Since it is a series hybrid only electrical machine is used to drive the vehicle,
The traction motor has to be sized for the maximum power requirements of the vehicle.
The highest power required is around 32kw so based on that two electric motors of
16kw of each are used for the vehicle
0 200 400 600 800 1000 1200
-30
-20
-10
0
10
20
30
40
Time[s]
Power[kw]
Requested Power[kw]

Table 3 Electric Motor Characteristics
Figure 12 Efficiency Map - Electric Motor
 The optimal efficiency range:
 Torque: 60 to 160Nm
 Speed: 260 to 820 rad/s
9.7 Electrical Machine Modelling
This efficiency map of electric motor is used to build a Simulink model of an electric
motor.
The values from this efficiency map is used in a 2-D lookup table to derive the electric
current required from the motor
Figure 13 Electric Motor (Simulink Model)
Electric Motor Efficiency
𝜼 𝑬𝒍𝒆𝒄𝒕𝒓𝒊𝒄𝑴𝒐𝒕𝒐𝒓 =
𝑻 𝑽𝒆𝒉 ∗ 𝝎 𝑽𝒆𝒉
𝑽 ∗ 𝑰
The inputs are torque and angular speed and the output is the efficiency of the electric
motor. With the help of electric motor efficiency and keeping the voltage as constant
at 250 volts. The requested current from each motor is calculated.
Type 16KW Permanent
magnet HUB
motor
Voltage control 250V
Maximum current 150A
Minimum Voltage 100 V
Mass 60kg

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9.8 Optimizing the operating points of electric motor to get the
best efficiency by changing the gear ratio
∫ 𝐼𝑛𝑝𝑢𝑡 𝑝𝑜𝑤𝑒𝑟  Input energy
∫ 𝑂𝑢𝑡𝑝𝑢𝑡 𝑝𝑜𝑤𝑒𝑟  Output energy
Efficiency of Electric motor=
𝑂𝑢𝑡𝑝𝑢𝑡 𝑒𝑛𝑒𝑟𝑔𝑦
𝐼𝑛𝑝𝑢𝑡 𝑒𝑛𝑒𝑟𝑔𝑦
Efficiency of any component is given by its output energy by input energy
Figure 14 Electric Motor - Operating Points
In the above figure we can see the operating points on the electric motor efficiency map.
We can observe that the motor is running at high torque and low speeds. Hence leading
to less operating efficiency at 72.5%
To increase the efficiency of electric motor a single gear ratio is used between the
wheels and the electric motor.
Figure 15 Electric Motor efficiency with different gear ratios
The above graph represents Efficiency vs Gear ratio.
That is efficiency of the electric motor is calculated for different gear ratios.
The highest efficiency is obtained for a gear ratio of 2.5 and by further increasing the
gear ratio efficiency starts decreasing. So due to this the gear ratio of 2.5 is selected.
Torque[Nm]
Speed[rad/s]
-150 -100 -50 0 50 100 150
0
100
200
300
400
500
600
700
800
0.3
0.4
0.5
0.6
0.7
0.8
0.9

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Figure 16 Electric Motor efficiency with 2.5 gear ratio
This figure shows the efficiency of electric motor with a gear ratio of 2.5
The overall Efficiency of Electric motor = 82.5%
Figure 17 Electric Motor - Operating Points with 2.5 gear ratio
The above figure shows the operating points of the electric motor. We can
observe that the torque is reduced by 2.5 times and speed is increased by 2.5
times to increase the efficiency of electric motor which is what the main goal of
using a gear between motor and the wheels.
1080 1100 1120 1140 1160 1180 1200
0.795
0.8
0.805
0.81
0.815
0.82
0.825
0.83
Time[s]
Eff[%]
Electric motor Efficiency[%]
Torque[Nm]
Speed[rad/s]
-150 -100 -50 0 50 100 150
0
100
200
300
400
500
600
700
800
0.3
0.4
0.5
0.6
0.7
0.8
0.9

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Figure 18 Model Integration NEDC - Vehicle Dynamics - Electric Motor
The above figure represents the entire model beginning from the NEDC to
the requested current from each electric motor.

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9.9 Final Result
9.9.1 Requested Current [A] from each electric motor
Figure 19 Requested current from one electric motor
The above fig shows us the requested from each electric motor. The positive values is
where the electric machine works as a motor and requests the current and the negative
values represent when the machine works as an electrical generator.
This is one of the input to the supervisor to decide the power distribution between
generator and the battery based on the current request or the current supply from the
electric motor
0 200 400 600 800 1000 1200
-60
-40
-20
0
20
40
60
80
Time[s]
Current[A]
Requested Current[A]from one motor

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10 Power Electronics
10.1Power Electronics Generator and Battery (Converters)
The converters are the electrical devices which convert the source of power. These are
unidirectional converters. The power convertors convert electric energy from one form
to another, converting between AC and DC or just changing the voltage or frequency or
some combination of these. These converters could be as simple as a transformer to
change the voltage of AC power, but also includes far more complex systems. The term
can also refer to a class of electrical machinery that is used to convert one frequency of
alternating current into another frequency. [17]
Power conversion systems often incorporate redundancy and voltage regulation. One
way of classifying power conversion systems is according to whether the input and
output are alternating current (AC) or direct current (DC).
10.2Classification of converters
DC to DC:
 DC to DC converter
 Voltage regulator
 Linear regulator
AC to DC:
 Rectifier
 Mains power supply unit (PSU)
 Switched-mode power supply
DC to AC:
 Inverter
AC to AC:
 Transformer/autotransformer
 Voltage converter
 Voltage regulator
 Cycloconverter
 Variable frequency transformer
There are devices and methods to convert between power systems designed for single
and three phase systems. The standard power frequency varies from country to country
and sometimes within the country.[17]

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10.3Rectifier
Figure 20 Rectifier
Table 4 Inputs to Converters
Input Unit Coming From
Current (AC) A Generator
Table 5 Outputs from Converters
Output Unit Going To
Current (DC) A Battery
With the explanation above, it can be seen the working of rectifiers. They convert
alternating current (AC) to direct current (DC) which flows in only one direction. This
process is known as rectification. Rectifiers take a number of forms including vacuum
tube diodes, mercury-arc valves, copper and selenium oxide rectifiers, semiconductor
diodes, silicon-controlled rectifiers and other silicon based semiconductor switches.
In our case, the efficiency of rectifiers is considered as 80%.

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10.4Inverter
 A power converter is an electrical or electro-mechanical device for control and
conversion of electrical energy
 An inverter is an electrical device that converts electricity derived from a DC (Direct
Current) source to AC (Alternating Current) that can be used to drive the electric
motor.
 Goal: to construct Invertor of small size and weight, which process substantial
power at high efficiency
 The devices used as switches in these converters are commonly IGBT, MOSFET or
Thyristor
Figure 21 Inverter Block

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10.5Power Electronics split-up (MODES)
Power Request from Electrical Request Machine [EM]
• 𝐸𝑀 𝑃𝑜𝑤𝑒𝑟>𝐺𝐸𝑁𝑃𝑜𝑤𝑒𝑟[110.43A]: Combined power from Generator and battery is
provided
• 𝐸𝑀 𝑃𝑜𝑤𝑒𝑟>𝐵𝐴𝑇𝑇𝑃𝑜𝑤𝑒𝑟&& < 𝐺𝐸𝑁𝑃𝑜𝑤𝑒𝑟[90 - 110.43A] : Power from Generator is
supplied and excess power is used to charge the battery
• 𝐸𝑀 𝑃𝑜𝑤𝑒𝑟<𝐵𝐴𝑇𝑇𝑃𝑜𝑤𝑒𝑟 [< 90A] : Power is supplied from Battery
• 𝐸𝑀 𝑅𝑒𝑔𝑃𝑜𝑤𝑒𝑟: Power is used to charge the battery
Figure 22 Current limits of different components along NEDC
10.5.1 𝑬𝑴 𝑷𝒐𝒘𝒆𝒓>𝑮𝑬𝑵 𝑷𝒐𝒘𝒆𝒓[110.43A]
In this state, the current request is greater than the generator power produced
therefore the combination of generator power and battery power is provided to run the
vehicle. This is clearly seen at the last peak when either the batter or generator or not
capable to provide the power. The last peak has a current request of 142 A, therefore
the generator provides its complete current which is 110.43A and the remaining 32 A is
supplied by the battery to run the vehicle.
10.5.2 𝑬𝑴 𝑷𝒐𝒘𝒆𝒓>𝑩𝑨𝑻𝑻 𝑷𝒐𝒘𝒆𝒓&& < 𝑮𝑬𝑵 𝑷𝒐𝒘𝒆𝒓[90 - 110.43A]
In this mode, the current request from the electrical machine is in between battery
current [90A] and that of generator current [110.43A], therefore the entire current is
provided by the generator and the remaining current is used to charge the battery.
0 200 400 600 800 1000 1200
-150
-100
-50
0
50
100
150
Time[s]
Current[A]
Current limits of different components along NEDC
Requested Current
Current GENERATOR
Current BATTERY
Current 0

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10.5.3 𝑬𝑴 𝑷𝒐𝒘𝒆𝒓<𝑩𝑨𝑻𝑻 𝑷𝒐𝒘𝒆𝒓 [< 90A]
In this mode, the current request from the electrical machine is lower than that of
battery [90A], therefore the entire current is provided by the battery to run the vehicle.
10.5.4 𝑬𝑴 𝑹𝒆𝒈𝑷𝒐𝒘𝒆𝒓
In this mode, there is no current request from the electrical machine but in-fact the
electrical machine works as a generator to charge the battery during braking.

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11 Battery
11.1Main Battery Types
The two main battery types are:
 Primary Batteries – Non-Rechargeable type
 Secondary Batteries – Rechargeable type
Primary Batteries are mainly used for small scale applications such as Watches,
Electronic keys, Remote Controls, Children toys and Military devices.
Secondary Batteries such as Lead-Acid, Nickel-Metal Hydride (NiMH) and Lithium-Ion
are used in medium and large scale applications where the battery utility is expected to
be for a long duration.
Note: lithium-Ion is the most preferable Consumer’s Choice.
11.2Selection of hybrid battery
11.2.1 Comparison of battery types
Table 6 Comparison of battery types
Primary batteries Secondary batteries
Primary batteries contribute 23.6 % of
the Global Market
Secondary Batteries contribute 76.4% of
the Global Market.
Frost & Sullivan predicts by 2015 the sales
will reduce to 7.4 % of the global market
The expected estimate of sales goes from
76.4% to 82.6 % by 2015.

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11.2.2 List of top batteries used by top hybrid car
manufacturers
Table 7 List of top batteries used by top hybrid car manufacturers
Top hybrid vehicle manufacturers Battery type
TOYOTA PRIUS Nickel Metal Hydride (NiMH)
HONDA INSIGHT Nickel Metal Hydride (NiMH)
VOLKSWAGEN TOUAREG Nickel Metal Hydride (NiMH)
LEXUS CT200h Nickel Metal Hydride (NiMH)
HYUNDAI SONATA Lithium Polymer
FORD FUSION Lithium Ion
HONDA CIVIC Lithium Ion
It is expected that Li-ion possess the maximum utility and an optimum choice for
Consumer Applications.
One of such application is the Evolution of Battery in Electric Power-train for Hybrid
Cars. Here to develop a well-equipped battery pack the basic requirements from the
consumer point of view is to design a battery at
 Low Cost
 Long life
 High Specific Energy
 Safe operation
 Minimal Maintenance
In addition the battery must work at Hot and Cold Temperatures and deliver High
Power demand and good Charging efficiency.
11.2.3 Comparison between different batteries
Table 8 Comparison between different batteries
BATTERY TECHNOLOGY CYCLE LIFE SPECIFIC POWER
(W/kg)
SPECIFIC ENERGY
(Wh/kg)
Li-ION BATTERY 400-1200 300-1500 150-250
LEAD-ACID BATTERY 500-800 150-400 30-40
NICKEL-METAL HYDRIDE
BATTERY
500-1000 250-1000 30-80

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Lithium is the lightest of all metals and has the greatest electrochemical
potential, providing large specific energy per weight. Rechargeable batteries are made
with lithium metal on the anode side to provide extraordinary Energy Density. It is
identified that during cyclic operation, lithium metal produces an unwanted dendrites
on the anode. These particles penetrate the separator causing “Electrical Short”. This
leads to rise in cell temperature and quickly approaches cell’s melting point, causing
thermal runaway known as “Venting with Flame”.
To overcome this instability during charging, a non-metallic solution called
“Lithium-Ion” is used. This technique is introduced to improve the safety issues of the
battery pack at high temperatures.
The Specific energy of Li-ion is twice that of NiCd and possesses high nominal
voltage of around 3.6 to 3.7V compared to 1.20V of NiCd or NiMH.
11.3Literature review [4] [5]
11.3.1 Hybrid car batteries
Hybrid car batteries come under the Secondary Battery classification as they are
Rechargeable in nature. These are manufactured in Packs depending upon the Voltage
demand of the consumers. These batteries are classified based on several chemical
combinations according to its chemical nature and the user requirements. They are:
 The battery must be designed for High Specific Energy and small size, but the
limitation is the cycle life is short.
 The battery must be built for High Load capabilities and durability, but the
limitation is the cells are Bulky and Heavy.
 The battery must be built based on High capacity and long service life, but the
limitation is the manufacturing cost is out of average manufacturing cost of other
battery types.
Based on these criteria, the common successful battery classifications that are used
in present Hybrid vehicles are:
11.3.2 Lead acid batteries
This is the conventional automotive battery, the oldest type of rechargeable
battery that has been around since the 1800s. Basically every automobile uses a lead-
acid battery to run its electrical system and accessories like the radio and headlights.
Even hybrids like the Toyota Prius use a lead acid battery to run these secondary
systems. Early electric cars were powered by lead acid batteries, and even General
Motor's EV1 was initially powered by lead acid.
But lead-acid batteries have serious limitations.
 They don't have great energy storage abilities,
 They're heavy, and the chemicals inside are hazardous.
 Lead-acid batteries have a relatively short lifespan.

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11.3.3 Nickel metal hydride
NiMh has a higher storage capacity than many types, including lead acid.
 This is good because the more energy that can be stored in a small space, the
easier it is for designers to pack enough batteries onboard to power the car.
 NiMh batteries have fewer toxic chemicals than lead acid batteries as well.
NiMh technology has been around since the 1970s so it's proven and relatively
inexpensive. That's part of the reason some automakers are sticking with it.
11.3.4 Honda’s Choice on NiMH
For example, Honda pointed out that the Honda CR-Z met all the company's performance, fuel
economy and price-point goals using NiMh batteries, which is why it didn't opt for fancier, more
expensive batteries. The same goes for Toyota, which has said that the Prius will continue to use
NiMh batteries for the foreseeable future.
11.3.4.1 Limitations of NiMH
 NiMh batteries need to be fully discharged regularly to avoid "memory" which
shortens the battery's life.
 They also generate more heat than NiCad or lead-acid batteries while charging.
Heat and heavy loads can also reduce battery life.
11.3.5 Lithium-ion batteries
Lithium-ion batteries are safer and less toxic than the others.
Compared to NiMh and lead acid batteries, Li-ion allows for the most energy storage in
the smallest space, which makes it ideal for automotive uses.
LONGER LIFE:
Li-ion batteries aren't affected by "memory" so they don't need to be fully
discharged to maintain a long life, making them basically maintenance free. Li-ion
batteries can also be stored for a long period of time without losing their charge. Li-ion
is the newest of the battery types and is being used in cars like the Chevrolet Volt and
Nissan Leaf. Tesla also uses Li-ion batteries in its Roadster.

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11.4Battery parameters
An Electric Cell possesses two main specifications.
Nominal Voltage (V)
Provides approximate voltage which the cell has to deliver to the electrical system. A
group of cells are connected in series to give the overall battery voltage.
Internal Resistance (mOhms)
Resistance towards electric current flow, which remains constant for both charging and
discharging, without taking the Amplitude of the current into account.
Capacity (Ahr)
The electric charge that a battery can supply is clearly a most crucial parameter. The
charge when one Amp flows for one second. The capacity of a battery might be, say,
10Amphours. This means it can provide 1Amp for 10 hours or 10Amp in 1 hour.
Energy Stored (Whr)
The energy stored in a battery depends on its voltage, and the capacity. The SI unit is
the Joule, but this is an inconveniently small unit, and so we use the Whr instead.
Energy in Whr = V *Ahr
Specific Energy (Wh.kg-1)
Specific energy is the amount of electrical energy stored for every kilogram of battery
mass. It has units of Wh.kg -−1.
Energy Density (Wh.m-1)
Energy density is the amount of electrical energy stored per cubic metre of battery
volume. It normally has units of Wh.m -−3
Specific Power (W/kg)
Specific power is the amount of power obtained per kilogram of battery. It is a highly
variable and rather anomalous quantity, since the power given out by the battery
depends far more upon the load connected to it than the battery itself. Unit – W/kg

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11.5Methods for selection – battery pack
11.5.1 Main classification of lithium-ion battery
Table 9 Characteristics of lithium battery types
SPECIFICATIONS Li-Titanate
(LiTi5O)
Li-Manganese
(LiMn2O4)
Li-Iron Phosphate
(LiFePO4)
VOLTAGE (V) 2.8V 3.30V 3.30V
CHARGE LIMIT (V) 2.25V 4.20V 4.0V
CYCLE LIFE 5000-1000 500-1000 1000-2000
OPERATING TEMP AVG AVG GOOD
SPECIFIC ENERGY
(Wh/kg)
150-190 Wh/kg 100-135 Wh/kg 90-120 Wh/kg
SAFETY Very safe Very safe Very safe
THERMAL RUNAWAY 500°C 250°C 270°C
COST Raw material high High High
Figure 23 Comparison of different chemistries for the batteries of Li-ion

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11.5.2 Justification
In general, Lithium-ion Phosphate (LiFePO4) possesses a good cycle life and a
comparatively high specific energy compared with the other two classes. And secondly
it has a good Resistive property towards ‘Thermal Expansion”.
 Thermal Expansion Stability in response to the Increase in Temperature is
good. This avoids cracks and maintains the life span of the battery for a long
duration compared to other batteries.
 Very low Internal Resistance towards Charging and Discharging will promote the
battery to achieve high SOC in a very short duration of charging.
 As the cell provides a good C-Rates (35C continuous), it can support and provide
a good range of charging and discharging current capacity with a low heat loss
 Life cycle or No or Depth Cycles of the Battery is quite longer compared to NiMH
as the battery can withstand high temperatures with less thermal expansion.

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11.6Hybrid Battery Sizing
11.6.1 Battery cell sizing technique
We should determine the total number of cells simply by determining the power
we need, then series or parallel arrangement depends on the voltage and current
requirement on the generator/motor. Number of cells (Energy content is the rated
capacity one multiplied by the number of cells being in parallel or series). If these cells
are in series then we add up the voltage at a constant current of one cell, if everything
is in parallel we add up the current.
Depending on the arrangement we can have a battery that is more suited to high
instantaneous power or more suited to have a large storage capacity. To have a high
power we need to have a large electrode surface and for high capacity you have to better
use the volume of the battery.
The following characteristics to be taken into account:
 Nominal Voltage (V) of the cell
 Rated Current (Ah) of the cell
 Nominal Charging Current (A) & Maximum Charging Current (A) charging at Constant
Current (CC) and Constant Voltage (CV)
 Nominal Discharging Current (A) & Maximum Discharging Current (A) at Constant
Current and Variable Voltage (VV)
 Internal Resistance of the Battery (mΩ)
 Weight of the battery (g)
 Temperature of the battery (°C)
So in order to achieve the Power, I have selected the Battery Cell on the basis of
Nominal Voltage (V) and the Capacity rates (C rates) of Charging and Discharging under
different State of Charge (SOC) ranges.
11.6.2 Literature review
Comparison between Different Cell Models
Different rechargeable Battery/Cell manufacturers are examined. The cell rating
differs from one another based on the purpose of usage. Certain cells are specifically
developed for Hybrid Vehicle Battery Packs. Like this a List of top Battery manufacturers
are considered for estimation. They are:
 LiFeBatt USA
 Altairnano
From the list a comparative analysis is been done in choosing the appropriate cell model
with a good charging and discharging rates that could meet the Motor Power
requirements.

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Table 10 Comparison between Different Cell Models [3]
Battery Manufacturer LifeBatt Altairnano
Cell Type LiFeBATT X-2E Li-ion
Model Name 40166 Cell Swing 9600
Weight/cell (g) 465 1800
Energy Density (Wh/kg) 850 207
Nominal Voltage (V) 3.65(V) 2.8(V)
Rated Capacity (Ah) 15(Ah) 12(Ah)
Internal Resistance of the Cell (Ohms) 0.003(Ω) 0.0155(Ω)
Charging Current (A) (0.5*C) 15(A) 3.71(A)
Max Charging Current @ Max Capacity (A) 75(A) 60(A)
Max Charging Voltage (v) 3.65(V) 4.2(V)
Max Charging Temp (deg C) 0 to 45(deg C) 23(deg C)
Cut-off Current (A) 75(A) 0.15(A)
Discharging Current (A) (1*C) 90(A) 5.3(A)
Disharging Current (A)@ max capacity
(1*C)
2.75(V) 13(A)
Max Discharging Voltage (V) (-)20 to 60 (deg C) 2.75(V)
Max Discharging Temp (deg C) 20 (deg C) 23 (deg C)

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11.6.3 Determination of battery pack assembly
Table 11 Determination of battery pack assembly
Battery
Type Lithium Ion
Nominal Voltage 250V
Maximum Discharge Current 90 A
Maximum Charge Current 45 A
Battery Arrangement 70 S
Weight 32 kg
No of Cells in Series – 70
Total No of Cells in the Battery Pack – 70
Net Weight of the Battery Pack – 30 kg
11.6.4 Sizing a cell
If we size a cell, if we change the capacity we change the size of the area of the
electrode, so if we decrease the area of the electrode we will also decrease linearly. If
we have half the capacity we have half the maximum current. The size of the electrode
is lower and what counts is the number of electrons that can move out of the electrodes
for a given area.
Usually a car has 3 times more braking power than traction power so during
braking phases we could have very high current which could exceed the maximum
current of the battery. This is why sometimes the stack can be designed for a higher
current for more capacity. Two types of arrangements Power and Capacity or Efficiency.
Of course if we put all resistances in series or in parallel we will not get the same result.

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11.7Hybrid battery modeling & simulation
11.7.1 Objective
 To study and analyze various battery technologies, presently used in Hybrid Vehicles
and to obtain the best Battery Cell to contribute a major part for improving the
Global Efficiency of the Electrical System
 To develop a Battery Model to satisfy the Power Requirement of the Electric motor
 Depending on the weight of the vehicle we have to dimension the battery
 To optimize the size and weight of the Battery pack, (optimum Energy-to-Weight
ratio)
 To determine the Charging & Discharging characteristics and the Global Efficiency
over the driving cycle.
11.7.2 Battery block
We cannot ask the battery to output the voltage we want it depends on what we
put on the battery. Eg: the amount of charge the battery holds. We can decide on
current but not on voltage. Voltage is an output but the current is an input
independently of the sign because the current will be driven by what the supervisor is
asking from the charging side and motor side. It is not the battery that decides the
current but the battery as a function of the current will determine the voltage.
Figure 24 Battery block
Voltage is an intensive variable and current is an extensive variable (it is a flow
like air). In physics every time the product of intensive variable and extensive variable
gives the power. Voltage depends on SOC. If we add current or electric charges to the
battery its voltage increases. Depending on the components we must ensure for
example if for the given electric motor we need the optimal voltage to run it so we have
to arrange the battery cells.
If the battery cannot supply the voltage required by the power of the motor will
be lower consequently torque will be lower and acceleration will be lower.

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11.7.3 State of charge
SOC is the level of the time power is speed at which you empty / fill your tank,
SOC is not completely dependent on the voltage. You can never measure the SOC, we
can measure only current and voltage. SOC is the integral of the current (number of
electrical charges). Integrate the current to build the SOC.
By integrating the current we can obtain the charge (number of electrons in the
battery) and this allows you to calculate the state of charge and as a function of SOC
depending on the battery technology we have a voltage curve. When a lead battery at
12V is almost dead.
11.7.4 Internal Resistance
For the battery temperature we need an internal resistance so we can compute
the Joule effect of the battery. We have to model some heat exchange with outside of
the battery because the battery will warm up.
This is the internal characteristics of the battery without taking into account the
resistance and then we have an additional resistance so with this resistance when you
are charging the battery because you have a current going in the your voltage will
increase. We have this voltage across the internal resistance which depends on
temperature and so with this we can also calculate the dissipation and the efficiency.
11.7.5 Energy
Because as a function of current we know the dissipation as a product of voltage
and current and so we can calculate the amount of power lost. So we can easily
understand that if we charge and discharge many times we lose a lot more power than
keeping the battery at a constant charge. We know we lose energy in the battery but we
have to check if we lose more or less that what we gain by shifting the operating point.
With a simple battery model the limit will be the internal resistance if we ask more we
simply end heating up or losing energy in the resistance.
Except for a plug in we don’t need much energy, in fact we are always keeping
the SOC at a medium level so we still have space for getting back energy during braking
phases. We have mid spikes when power required or braking phases.
Depending on the weight of the vehicle we have to dimension the battery but with very
large battery we don’t gain much and in the end we could lose because we have more
weight in the vehicle and so we will have more fuel consumption.

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11.7.6 Designing a battery
We can design a battery with high capacity but low maximum power or high
power lower capacity (compromise) and it is mainly due to internal design of electrodes.
Depending on the nominal voltage the batteries has different stacks, the series
or parallel arrangement and this will give the different compromise on capacity and
maximum power. The main difference is how we stack the batteries (cells).
11.7.7 Basic battery model
A battery is basically a voltage source and resistance. If I am charging the battery,
I will have current and here the voltage we have the sum of those. If we are charging, so
what the battery sees is less than what we are applying because we have losses in
resistance and this loss depends on the current, if the battery voltage is here and we are
charging at that level.
Now when we are emptying the battery we have the opposite, we have current
flowing this way, it is the voltage that has changed the sign but not the battery so now
when we are drawing the current from battery, suddenly the voltage is dropping not
because of the battery or SOC, because of the Internal resistance because the sign of
the voltage is changed, if current changes its sign it changes.
Figure 25 Voltage vs State of Charge
Voltage is not completely constant, it goes up slowly because the voltage is a
function of the SOC, when charging it goes up and then increases. So the inner model of
the battery is simply series resistance and then we have a real voltage generator and
this voltage generator is integrating the current.
We have the charge of the battery which is the integral of the current. So we
integrate the current going in and we have the losses. SOC is simply C/Ct which is the
total nominal charge of the battery.
Voltage drop is resistance multiplied by the current. So if we have high current
we have high voltage drop. Internal resistance changes with function of temperature,
wear.

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11.8Modelling a battery
When modelling a battery is too small in fact we don’t have enough energy
stored and overall efficiency will drop. If the battery is too large you have enough energy
stored more than we need and battery is heavy and we lose during acceleration and
deceleration. We simply need energy to accelerate this weight and then during
deceleration we get some energy back through a chain of efficiencies where there are
losses so we get back less than what we have spent.
We can design a battery for high capacity but low maximum power or the
opposite. Compromise is mainly because of the electrodes and because of its high
surface and so on. Depending on the sizing of the inner components you can have high
instantaneous power but low capacity or the opposite.
Voltage battery and a series resistor and this will follow this rule:
The SOC is simply the amount of charges integrated from the current. And the
full voltage is the voltage of the cell or cell arrangement minus the voltage drop across
the resistance when you discharge and when you charge.
Example: When we charge a battery at around 14V and unplug the charger it
drops back to 13.6V this is because of the resistance, because this 0.4V are the voltage
difference and the same when we use a battery. Example: When we start engine when
its cold outside it can go down to 8V and then when we release the starter it will go back
to 13V because of the internal resistance. On a tractor engine start(John Deere) did a
cold water test at -30°C and the starter was pulling 2000A from the battery with this
level of intensity of the voltage drop can get very high.
11.8.1 Simulink Library
Figure 26 Simulink library for Battery components
 Generic Battery Model
 Resistor
 Current measurement
 Voltage measurement
 RELAY (SOC)
 Gain
 Scope
 Power grid (continuous)

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11.8.1.1 Relay
For switching mode (charging & discharging) we use an “Electric Relay”. This relay
does the shifting operation based on the SOC ranges of the battery.
Figure 27 Relay Mechanism
In this relay, we set the SOC ranges from 80% (max range) to 20% (min range). A
discharging current of 90A is delivered by the battery when the SOC drops from 80% to
20%. And during the second operation, a charging current of -120A is generated by the
current source to the battery to raise the SOC range from 20% to 80%. In this way the
battery is discharged and charged for different cycle.
11.8.1.2 Maximum capacity and Rated capacity
These are electrochemical effects completely emptying the battery. Usually we
have a limited range inside the total range. Even battery manufacturers don’t know
about that. The idea was sometimes we could very much improve the driving cycle if we
can only go a little bit outside of the rated capacity only few seconds.
Electrochemistry is not simple because it depends on materials, structure of
materials, thermal effects, chemistry, electrolytes (we have flow). Today most of the
battery manufacturers do some tests on trial and error to understand what happens so
they have global guidelines but not clear understanding where we can decide.

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11.8.2 Simulink model of the battery
Figure 28 Simulink model of the battery
11.8.2.1 Inside the battery
Maximum current is given in the specifications. In a battery we want the largest
possible area on the electrodes, the limit is the thermal battery. Minimum volume and
the minimum weight. What we need to have is a very rough surface.
Roughness is determined by the real area and the average area demanding the
outside surface of the electrode. Roughness is the real area divided by the area driven.
The ratio can be very high more than 10 and 20 because of the roughness.
If we ask high current you have spike effect or heat effect, the high current is
taken from the very small spots and volume is very small so it will heat up and these
parts of the electrodes will melt together.
So the roughness will decrease with time and this battery ageing. This is why with
time the battery has a lower capacity and lower maximum intensity because the real
surface reduces with time and it reduces more if you ask higher current and if you ask
infinite current you will melt everything.
So this is why there is a rated current which doesn’t remove all these effects but
will slow it down so the battery will last 5 years on an average.

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11.8.3 Charging and discharging characteristics
Figure 29 Charging and Discharging Characteristics of the battery
Here we impose the current and because the SOC is the integral of the current
so we have this saw tooth curve. We integrate a constant positively and negatively so
we simply see the slope of the integral of the current but then for the given material of
the battery we have this curve which represents the output voltage as a function of the
SOC.
We have the steps here because of the internal resistance. We are losing voltage
in one direction when charging and the other direction when discharging the battery. So
when charging we see a high voltage and when we disconnect it, it drops quickly and if
we discharge we can see a voltage drop.
11.8.4 Global Efficiency over the Driving cycle
The Global efficiency during the whole cycle, integrate the incoming power and
integrate the outgoing power and ratio will be the efficiency from start of the cycle to
that given point and at the end we will have the global efficiency of that component
over the driving cycle.
This will allow us to size the components. We have to increase the efficiency on
the whole driving cycle. We know the best efficiency of each of those and then we have
this average efficiency through the driving cycle.
We see that we have a bad global efficiency, sometimes it is running at good efficiency
so the average is not so good. Sometimes it is better to shift the operating points that
range where the operating is less good but all the rest will be better. Global trade will
be better.
Efficiency very much depends on the current so of course because it is a
resistance so if we charge a battery slowly the efficiency is very good we can have 90%.
If we charge or discharge it faster than we have lot of losses. So this efficiency number
is very much dependent on how much we charge and discharge a battery.

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Figure 30 Simulink model to determine the global efficiency of the battery
The Global efficiency of the battery for charging & discharging over the driving
cycle is
(ηc/d) = 0,934 (or) 93 %
Calculate the power, by integrating power we get the energy and we have to
calculate the incoming energy and outgoing energy and the ratio will be the efficiency.
Or if we are charging and discharging the battery we can integrate how much energy we
put in the battery and how much we draw from the battery for a same range of SOC.
Ratio is the efficiency.

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12 Generator
Generator is a device that converts mechanical energy to electrical energy for use in an
external circuit. The source of mechanical energy may vary widely from a hand crank to
an internal combustion engine (ICE).
The generator is coupled to the ICE and both the ICE and generator are operated at their
optimal points for better performance and efficiency.
12.1Terminology
Mechanical
 Rotor – The rotating part of an electrical machine
 Stator – The stationary part of an electrical machine
Electrical
 Armature – The power producing component of an electrical machine. In a
generator, alternator or dynamo the armature windings generate the electric
current. The armature can be on either the rotor or the stator.
 Field – The magnetic field component of an electrical machine. The magnetic
field of the dynamo or alternator can be provided by either electromagnets or
permanent magnets mounted on either the rotor or the stator.
12.2General representation
Figure 31 General representation of Generation
Table 12 Inputs to Generator
Input Unit Coming From
Torque Nm ICE
Speed Rad/s ICE
Table 13 Outputs from Generator
Output Unit Going to
Current (AC) A Power Electronics

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12.3Selection
The generator is selected from the Advisor software. This software provides all the
required data for each individual component.
12.3.1 Benefits
 Efficiency maps easily available
 Comparison of various generator data with each other based on the efficiency
just by changing the name of the generator in the matlab script
 Reduction in time spent for research and utilized in other domains
 Carrying out modelling with help of efficiency maps available
12.4Specifications
Table 14 Specification of Generator
Type 32 KW Permanent Magnet Generator
Voltage control 195 V
Maximum current 300 A
Minimum voltage 60V
Inertia 0.0226 kg * m2
Mass 38.1 kg
Average heat capacity 430 J/Kg-K
Thermostat temperature 45oC
Total module surface 0.2175m2

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