Vehicle Propulsion Systems Lecture 4. Outline. The Vehicle Motion Equation. Energy consumption for cycles. Engine Efficiency Maps.

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1 ehicle ropulsion Systems Lecture 4 Hybrid owertrains, Topologies and Component Lars riksson rofessor ehicular Systems Linköping University arch 23, / 64 2 / 64 Introduction to Hybrid-lectric ehicles otential lectric ropulsion Systems Overview of Hybrid lectric Configurations lectric motors, enerators atteries, Super Capacitors Transfer of ower xtra aterial The ehicle otion quation Newtons second law for a vehicle m v d dt v(t) = F t(t) (F a (t) + F r (t) + F g (t) + F d (t)) F t tractive force Fr α Fg mv g F a aerodynamic drag force F r rolling resistance force F g gravitational force F d disturbance force Fa Ft Fd 3 / 64 4 / 64 nergy consumption for cycles ngine fficiency aps easured engine efficiency map Used very often Numerical values for -95, C, UDC air drag = 1 xtot rolling resistance = 1 xtot kinetic energy = 1 xtot v 3 i h = {319, 82.9, 455} i trac v i h = {.856, 0.81, 0.88} i trac ā i v i h = {0.101, 0.126, 0.086} i trac Willans line approximation Ē -95 A f c d mv cr mv 10 kj/100km [bar] model measurement Intake manifold pressure [bar] 5 / 64 6 / 64 odel implemented in QSS Conventional powertrain. fficient computations are important For example if we want to do optimization and sensitivity studies. 7 / 64 Introduction to Hybrid-lectric ehicles otential lectric ropulsion Systems Overview of Hybrid lectric Configurations lectric motors, enerators atteries, Super Capacitors Transfer of ower xtra aterial 8 / 64

Definition otential for nergy Savings What characterizes a Hybrid-lectric ehicle nergy carrier is a fossil-fuel. resence of an electrochemical or electrostatic energy storage system.

prime movers liminate idle fuel consumption by turning off the engine (stop-and-go) liminate the clutching losses by engaging the engine only when the speeds match ossible

9 / 64 10 / 64 lectric ehicles asic topology Sketch of the paths lectric vehicle lectric ehicles Contain basic elements of H. Not interesting, for optimization.

Drawbacks compared to a conventional vehicle Not autonomous Refueling time Low range/weight Niche vehicles lug-in :s are hot in media Development of plug-less vehicles Inductive

.. In-city distribution vehicles Zero emission vehicle requirements Other niched vehicles Lightning Nissan Leaf, olvo C30 lectric Tesla Roadster 13 / 64 Introduction to

2 Definition otential for nergy Savings What characterizes a Hybrid-lectric ehicle nergy carrier is a fossil-fuel. resence of an electrochemical or electrostatic energy storage system. enefits of Hybrid-lectric ehicles Downsize engine while maintaining maximum power requirement Recover energy during deceleration (recuperation) Optimize energy distribution between prime movers liminate idle fuel consumption by turning off the engine (stop-and-go) liminate the clutching losses by engaging the engine only when the speeds match ossible improvements are counteracted by a 10-30% increase in weight. 9 / / 64 lectric ehicles asic topology Sketch of the paths lectric vehicle lectric ehicles Contain basic elements of H. Not interesting, for optimization. No in-depth coverage in the course. Interesting from the design point of view. Drawbacks compared to a conventional vehicle Not autonomous Refueling time Low range/weight Niche vehicles lug-in :s are hot in media Development of plug-less vehicles Inductive charging Range extenders (transition to series hybrid) 11 / / 64 lectric ehicles From Niche to ublic Applications requiring zero-emissions. Indoor vehicles, mines... In-city distribution vehicles Zero emission vehicle requirements Other niched vehicles Lightning Nissan Leaf, olvo C30 lectric Tesla Roadster 13 / 64 Introduction to Hybrid-lectric ehicles otential lectric ropulsion Systems Overview of Hybrid lectric Configurations lectric motors, enerators atteries, Super Capacitors Transfer of ower xtra aterial 14 / 64 asic configurations Topology asic classification of hybrids Series hybrid arallel hybrid Series-parallel or combined hybrid There are additional types that can not be classified into these three basic types Complex hybrid (sometimes) Sketch of the topology asic 15 / / 64

odes and ower Flows The different modes for a series hybrid attery drive mode u batt / vehicle attery drive mode, u=1 attery

Regenerative braking mode Regenerative braking mode, u=1 Sketch of the topology asic 19 / 64 20 / 64 odes and ower Flows The

attery recharging mode, u<0 Sketch of the topology ild T ower assist mode ower assist mode, 0<u<1 21 / 64 22 / 64 Regenerative

3 odes and ower Flows The different modes for a series hybrid attery drive mode u batt / vehicle attery drive mode, u=1 attery recharge mode attery recharge mode, u<0 17 / 64 Hybrid drive mode Hybrid drive mode, 0<u<1 18 / 64 Topology Topology Regenerative braking mode Regenerative braking mode, u=1 Sketch of the topology asic 19 / / 64 odes and ower Flows The different modes for a parallel hybrid ild Topology u batt / vehicle attery drive mode (Z) Z mode, u=1 attery recharge mode attery recharging mode, u<0 Sketch of the topology ild T ower assist mode ower assist mode, 0<u<1 21 / / 64 Regenerative braking mode Regenerative braking mode, u=1 Topology Topology Conventional vehicle Conventional vehicle mode, u=0 Sketch of the topology T 23 / / 64

with S odes and ower Flows The different modes for a combined hybrid Conventional vehicle Note the loop ngine only mode Without lanetary ear T T ower assist mode Note the loop ower assist mode T 25 /

4 with S odes and ower Flows The different modes for a combined hybrid Conventional vehicle Note the loop ngine only mode Without lanetary ear T T ower assist mode Note the loop ower assist mode T 25 / / 64 attery drive mode (Z) Z mode Degree of Hybridization Summary of different hybrid concepts T attery Degree recharge of hybridization mode The Combined ratio Hybrid between electric motor power and engine power. attery recharging mode Implemented hybrid concepts in cars Degree of hybridization varying between 15 55% True mild hybrid concepts Degree of hybridization varying 2 15% T Feature Conv. icro ild Full lug-in Shut of engine at stop-lights and stop-go traffic (x) X X X Regenerative braking and operates above 42 X X X lectric motor to assist a conventional engine X X X Can drive at times using only the electric motor X X Recharges batteries using the wall plug with at least 32 km range on electricity X Regenerative braking mode Regenerative braking mode T 27 / / 64 State Of Charge SOC Charge condition for the battery. Full range SOC 0 100%. Used range SOC 50 70%. enerally difficult problem odels that include aging are not (yet) good enough. Charge Sustaining Strategy Charge Sustaining Strategies asic control problem for a hybrid SOC after a driving mission is the same as it was in the beginning Advisor simulation lug-in hybrids Not charge sustaining 29 / / 64 Introduction to Hybrid-lectric ehicles otential lectric ropulsion Systems Overview of Hybrid lectric Configurations lectric motors, enerators atteries, Super Capacitors Transfer of ower xtra aterial lectric otors Classification lectric motors are often classified into four groups (there are other classifications) DC-achines Synchronous machines (sometimes including brushless DC-motor) Asynchronous machines Reluctance machines There are also other devices: Stepper motors (Digitally controlled Synchronous achine), Ultrasonic motors. Separate course: electrical drives. 31 / / 64

The 4 Quadrants T 2 1 raking Driving ω Driving raking 3 4 1 - otor, 4 - enerator, 2,3 - Reversing rushed DC-achine Wikipedia picture rush-type DC motor: Rotor Stator Commutator Two subtypes: ermanent

Solves DC commutator and brushes problem Replace electromagnet in rotor with permanent magnet (). Rotate field in stator.

5 The 4 Quadrants T 2 1 raking Driving ω Driving raking otor, 4 - enerator, 2,3 - Reversing rushed DC-achine Wikipedia picture rush-type DC motor: Rotor Stator Commutator Two subtypes: ermanent magnet Separately excited ros and cons + Simple to control rushes require maintenance 33 / / 64 DC-motor torque characteristics rushless DC-otor Characteristics of a separately excited DC-motor Solves DC commutator and brushes problem Replace electromagnet in rotor with permanent magnet (). Rotate field in stator. DC-motor is misleading DC source as input lectronically controlled commutation system AC Linear relations between current and torque voltage and rpm 35 / / 64 Synchronous AC machines AC machine Rotor follows the rotation of the magnetic field Has often permanent magnets in rotor This is the same as the brushless DC motor. Torque Characteristics rushless DC 37 / / 64 Asynchronous AC machines Induction motors Stator has a rotating magnetic fiels Rotor has a set of windings, squirrel cage See separate animation. lectric field induces a current in the windings Torque production depends on slip. Torque Characteristics Induction AC motor 39 / / 64

6 Reluctance machines Reluctance = agnetic resistance. Synchronous machine Rotating field agnetic material in the rotor Rotor tries to minimize the reluctance lectrical achines in Hybrids achines encountered Separately excited DC ermanent magnet synchronous DC Induction motors (Switched reluctance machines) Considered to be interesting AC motors (compared to DC motors) Less expensive but more sophisticated control electronics, gives higher overall cost. Higher power density, higher efficiency. AC motors (permanent magnet vs induction motors) Averaged values from Advisor database. fficiency ower density permanent magnet 92.5 % 0.66 kw/kg induction motors 90.5 % 0.76 kw/kg 41 / / 64 otor First quadrant maps for η m AC machines Synchronous Quasistatic (equations are general) ower relationships: input power 1 (t) delivered power 2 (t) = T 2 (t) ω 2 (t) fficiency usage 1 (t) = 2 (t)/η m (ω 2 (t), T 2 ), 2 (t) > 0 1 (t) = 2 (t) η m (ω 2 (t), T 2 ), 2 (t) < 0 Description of the efficiency in look-up tables Willans line to capture low power performance Induction motor, Asynchronous AC 43 / / 64 xtending the aps for η m Traditional first quadrant drive is normally well documented Supplier information for η m ( ) lectric motor drive Two Quadrant aps for η m 2 (t) = η m (ω 2 (t), T 2 ) 1 (t), 2 (t) > 0 lectric generator load 1 (t) = η g (ω 2 (t), T 2 ) 2 (t), 2 (t) < 0 How to determine η g? ethod 1: irror the efficiency map η m (ω 2 (t), T 2 ) = η g (ω 2 (t), T 2 ) ethod 2: Calculate the power losses and mirror them ethod 3: Willans approach irroring efficiency is not always sufficient. 45 / / 64 otor ore advanced models Use component knowledge: Inductance, resistance uild physical models Dynamic models are developed in the book. 47 / 64 Introduction to Hybrid-lectric ehicles otential lectric ropulsion Systems Overview of Hybrid lectric Configurations lectric motors, enerators atteries, Super Capacitors Transfer of ower xtra aterial 48 / 64

atteries in QSS Framework nergy storage devices nergy density important erformance ower density important Durability Causality for attery models in QSS.

component is I 2 = 2 The other, the relation between voltage and terminal current SOC = f (SOC, I 2,.

Ion atteries attery data from Alelion in otenburg, 550 days 2048 cycles. Aging is visible over the cycles. Typical characteristics. Can extract inner resistance, and capacity.

7 atteries in QSS Framework nergy storage devices nergy density important erformance ower density important Durability Causality for attery models in QSS. 2 I 2 A T Q nergy ower cycles attery type Wh/kg W/kg Lead-acid Nickel-cadmium Nickel-metal hydride Lithium-ion odels have two components The first component is I 2 = 2 The other, the relation between voltage and terminal current SOC = f (SOC, I 2,...) 49 / / 64 Standard model oltage and SOC Simple model for the battery Open circuit voltage U oc R i Uoc I 2 Output voltage = U oc R i I 2 51 / / 64 oltage and SOC attery Ageing Lithium Ion atteries attery data from Alelion in otenburg, 550 days 2048 cycles. Aging is visible over the cycles. Typical characteristics. Can extract inner resistance, and capacity. (Source: batteryuniversity.com) 53 / / 64 SOC drift over time Coulombic Inefficiency Top: Reset so the cycle starts at 0 Ah every cycle. ottom: No reset, charge drifts, electrons lost per cycle. attery fficiency definition fficiency definition is problematic Not an energy converter nergy storage eukert test Constant current during charge and discharge. Ragone test Constant power during charge and discharge. fficiency will depend on the cycle. d = c = tf 0 tf 0 2 (t)dt = /eukert test.../ = t f (U oc R i I 2 ) I 2 2 (t) dt = /eukert test.../ = t f (U oc +R i I 2 ) I 2 η b = d c Can also define an instantaneous efficiency. 55 / / 64

fficiency definition Instantaneous Supercapacitors Supercapacitors and ultracapacitors High power density Used as short time scale energy buffer. Load leveling to the battery.

8 fficiency definition Instantaneous Supercapacitors Supercapacitors and ultracapacitors High power density Used as short time scale energy buffer. Load leveling to the battery. ery similar to battery in modeling xchange the battery for a capacitor in the circuit below. C U oc R i I 2 U oc (t) = Q(t) C = 1 C fficiency definitions eukert and Ragone I(t)dt 57 / / 64 Introduction to Hybrid-lectric ehicles otential lectric ropulsion Systems Overview of Hybrid lectric Configurations lectric motors, enerators atteries, Super Capacitors Transfer of ower xtra aterial 59 / 64 lectrical glue components DC-DC converters DC-AC converter Account for power losses 60 / 64 Torque couplers Components that are included to: lue for mechanical systems acting on the same shaft Can include: ears in the coupling equation Sub models for friction losses asic equations Angular velocities Torque (from a power balance, including losses) anage power splits between different components Important component for achieving flexibility approach: Speed relations with torque from power balance. 61 / 64 Can add more planetary gears 62 / 64 Introduction to Hybrid-lectric ehicles otential lectric ropulsion Systems Overview of Hybrid lectric Configurations lectric motors, enerators atteries, Super Capacitors Transfer of ower xtra aterial 63 / 64 assenger cars arallel hybrids Combined hybrids ery few series hybrids (range extenders to ). Trucks and busses Series hybrids arallel hybrids Combined hybrids Diesel trains Series configuration but no storage 64 / 64

9 08 List of Hybrid assenger Cars (Incomplete) Chevrolet Silverado Hybrid Truck, Chevrolet Tahoe Hybrid Daihatsu Highjet Ford scape, Ford ercury ariner Hybrid C Sierra Hybrid Truck, C Yukon Hybrid Highlander Hybrid Honda Accord Hybrid, Honda Civic Hybrid, Honda Insight Hybrid Landrover Hybrid Lexus S450h, Lexus RX 400h Nissan Altima orsche Cayenne Hybrid Saturn U reenline Hybrid Suzuki Twin Toyota Alphard Hybrid, Toyota Camry, Toyota stima Hybrid, Toyota rius Twike 65 / 64

4 Wikipedia picture. Brushed DC-Machine. The 4 Quadrants. DC-motor torque characteristics. Brushless DC-Motor. Synchronous AC machines

4 Wikipedia picture. Brushed DC-Machine. The 4 Quadrants. DC-motor torque characteristics. Brushless DC-Motor. Synchronous AC machines Vehicle Propulsion Systems Lecture 5 Hybrid Powertrains Part 2 Component Modeling Lars Eriksson Associate Professor (Docent) Vehicular Systems Linköping University November 5, 21 Energy consumption for