Effect of turbo-compounding technology on the performance of

 Effect of turbo-compounding technology
on the performance of
internal combustion engines
Filippo Patruno
Supervisor : Prof. Michele Manno
Bachelor’s degree in Engineering Sciences
University Of Rome Tor Vergata
Context Forced Induction : is the process of delivering compressed air to the intake of an IC engine Supercharging : mechanically driven compressor Turbocharging : compressor is coupled to an exhaust gases driven turbine Exhaust Gases Energy A.M.I. Mamat et al. / Energy 64 (2014) 3e16
7
Fig. 2. Available energy at exhaust exit.
Table 2
Turbine operating requirements.
Turbine power
1.0 kW
which enables to overcome the limitation of choking and surge
typical of a compressor device [26,27]. Extensive explanation about
the test-facility was previously published by the Imperial College
Electric Turbo-­‐Compounding System Issue : Unexploited waste heat up to 30 – 40 % only partially recovered by the turbocharger group in the standard engine configuration Application : Installation of a Power Turbine coupled to an electric generator •  Utilization of exhaust energy for additional power generation •  Conversion to mechanical or electrical energy •  Useful energy is stored in battery packs Jacopo Dellachà et al. / Energy Procedia 45 (2014) 1047 – 1056
1050
Analysis : Conducted by assuming as varying parameter the rotational speed of power turbine shaft ranging from 60 krpm to 110 krpm, with the purpose of detetermining nteraction between the PT and a Jacopo Dellachà
al. / Energy Procedia 45t(he 2014)i1047
– 1056
PT turbocharged diesel engine at different loads for fixed engine speed. = Standard engine + turbo-­‐compounding EG the engine is 27 bar and the engine power has a maximum value of
334.13 kW at 1700 rpm engine speed. The effect of proposed turbocompounding technology on engine performance has been
examined at various operating conditions. In the present analysis,
the examined engine loads are: 100%, 75% and 50% at 1700 rpm engine speed. The required data for the standard engine without turbocompounding and the corresponding T/C are provided in Tables
1 and 2 respectively. For the present investigation, the fueling rate
and the injection advance of the examined turbocompounded engine have been maintained the same as for the non-turbocompounded case (standard engine operation). It should be
gation. Details for the model validation have been provided in a
previous paper [21].
Reference engine specifications 5. Results and discussion
In this section, the theoretical results, which were generated
under the aforementioned parametric investigation, are provided.
For the sake of brevity of space, predictions are given only at
1700 rpm engine speed since the corresponding results at
1300 rpm and 2100 rpm are quite similar. As already mentioned,
The diesel engine considered is a six-­‐cylinders turbocharged truck engine with the following operating data Table 1
Operating data for the standard engine without turbocompounding.
Load (%)
100
75
50
_ fuel (kg/h)
m
Injection advance (deg ATDC)
11.80
%8
3.08
28.03
8.90
%8
2.65
20.88
6.10
%7
2.23
13.92
C.O. Katsanos et al. / Energy Conversion and Management 76 (2013) 712–724
operating chart. In addition, the T/C turbine effimated from the corresponding efficiency chart.
ues of mass flow rate and speed are calculated
d (14) at each time step, where the exhaust presure values correspond to the previous time-step.
n procedure continues with the simulation of
d the methodology is the same with the turboxcept from the fact that power turbine speed is
er.
ilibrium and continuity law for the turbocharger
the following expressions respectively:
erturb nmTC
ð17Þ
mfuel
ð18Þ
gy equilibrium for turbocharger is not satisfied
on procedure is repeated and the updated boost
provided from the following equation of the en-
rturb
ncompr nmTC þ 1
ir T air;in
pboost (bara)
%1
"cair
c
air
ð19Þ
y law is invalid for the turbocharger then the air
recalculated for the next operating cycle accordng expression:
AF (%)
pexh (bar)
Texh (oC)
Power (kW)
24.41
28.65
35.11
2.66
2.41
2.24
585.40
501.95
420.20
334.13
248.86
165.91
717
Table 2
Operating data for the standard turbocharger.
Load (%)
Effcompr (%)
Effturb (%)
NTC (krpm)
100
75
50
72.0
73.5
73.0
72.0
73.5
73.0
98.84
89.301
79.191
mentioned that the efficiency of the electric generator coupled to
the power turbine was also assumed constant and equal to 95%.
At this point, it must be mentioned that the brake specific fuel
consumption (bsfc) of the electrically turbocompounded HD diesel
engine is calculated (in g/kWh) using the following relation:
bsfc ¼
_f
m
PowerNET þ PowerGEN
ð21Þ
_ f is the engine fuel consumption in g/h, PowerNET is the net
where m
engine brake power output in kW and PowerGEN is the generated
electric power in kW. Hence, the percentage variations of bsfc and
C.O. Katsanos , Dpower
.T. Hountalas , T.C. Zannis net engine
brake
are calculated
according
to the following
expressions:
Thermal Engineering Section, School of Mechanical Engineering National Technical University of Athens bsfc variationð%Þ ¼
bsfcET % bsfcST
& 100%
bsfcET
PowerNET;ET % PowerNET;ST
ð22Þ
at 50%, 75% and 100% load. Hence, it is observed a decrease of
turbine expansion ratio for the operation of the examined HD
The effect of power turbine speed on the calculated mean exFig
Fig. 3a. Effect of power turbine speed on mean exhaust pressure at T/C turbine inlet
sel engine
with
electric
turbocompounding
compared
to
conv
haust pressure at T/C turbine inlet (high-pressure manifold) (high-pressure
is
Pre
manifold). Predictions are given for an electrically turbocompound(bl
tional
operation.
hown in Fig. 3a for the electrically turbocompounded HD diesel
ed HD diesel truck engine (black color lines) and the same engine without
for
turbocompounding
(standard
case
–
blue
color
lines)
at
1700
rpm
and
at
100%,
75%
ngine at 1700 rpm and at 50%, 75% and 100% of full load. In
170
and 50% of full engine load. (For interpretation of the references to color in this
ig. 3a are given also the corresponding mean exhaust pressure
ref
Effect on exhaust pressure at T/C turbine inlet and on power turbine expansion ratio figure legend, the reader is referred to the web version of this article.)
thi
Fig. 4.ofEffect
powerspeed
turbine
speed
on T/C
compressor
and
Fig. 3b. Effect
powerof
turbine
on its
expansion
ratio.
Predictions
areturbine
given efficien
Fig
ig. 3a. Effect of power turbine speed on mean exhaust pressure at T/C turbine inlet
Predictions
are
given
for
an
electrically
turbocompounded
HD
diesel
en
for an electrically turbocompounded HD diesel truck engine at 1700 rpm and at truckPre
high-pressure manifold). Predictions are given for an electrically turbocompound(black
lines
for
compressor
efficiency
and
red
lines
for
T/C
turbine
efficiency
100%, 75% and 50% of full engine load.
170
d HD diesel truck engine (black color lines) and the same engine without
for
the
same
engine
without
turbocompounding
(blue
lines
–
standard
cas
urbocompounding (standard case – blue color lines) at 1700 rpm and at 100%, 75%
1700 rpm and at 100%, 75% and 50% of full engine load. (For interpretation o
nd 50% of full engine load. (For interpretation of the references to color in this
references to color in this figure legend, the50%
reader is referred to the web versi
gure legend, the reader is referred to the web version of this article.)
this article.)
75%
The operation of the rotational PT opposes the free flow of exhaust gases to the ambient : Significant increase of backpressure at the exhaust manifold connecting the engine with the T/C turbine P
T/C turbine expansion ratio decreases β = ex P
pt
ΔP
= 1.26bar
ΔP
= 2.09bar
ΔP100% =2.84bar
Effect on T/C components efficiency Starting from a fixed optimized value for the Efficiency : Turbine : efficiency decreases because of the expansion ratio reduction Compressor : efficiency decreases due to shaft rotational speed reduction which changes the value of the boost pressure Efficiencies reduction are due to the fact that the turbocharger is not working at its designed operating point which is assumed for the standard engine configuration Reduction of turbine generated torque Reduction of T/C shaft rotational speed Fig. 6. Effect of power turbine speed on turbocharger rotational speed. Predictions
are given for an electrically turbocompounded HD diesel truck engine (black lines)
and for the same engine without turbocompounding (blue lines – standard case) at
1700 rpm and at 100%, 75% and 50% of full engine load. (For interpretation of the
references to color in this figure legend, the reader is referred to the web version of
this article.)
tween T/C turbine outlet and power turbine inlet is notice
ought to the initial expansion of exhaust gas in the T/C turbin
Effect on boost pressure and on air fuel ratio 719
C.O. Katsanos et al. / Energy Conversion and Management 76 (2013) 712–724
The increase of mean engine back-pressure (i.e. exhaust pressure between engine and T/C turbine inlet), which accompanied
the application of turbocompounding technology, is primarily
attributed to the operation of the rotational power turbine, which
is opposed to the free flow of exhaust gases to the ambience. As
will be shown in following paragraphs, the reduction of T/C turbine
expansion ratio mainly at part loads as a result of the application of
electrical turbocompounding affects directly the efficiency of the T/
C turbine (Fig. 4) and thus, the rotational speed of the T/C shaft
(Fig. 6). In addition, it will be shown that the increase of exhaust
back-pressure and the reduction of T/C turbine expansion ratio affect directly the supply of charge air (Figs. 7a and 7b)) to the diesel
engine by the T/C compressor and subsequently, affect the in-cylinder air to fuel stoichiometric analogy and the combustion efficiency and finally, the exhaust gas temperature (Fig. 8a) and the
net engine power (Fig. 9b).
Fig. 8a. Effect of power turbine speed on the mean values of exhaust temper
In Fig. 3b is presented the effect of power turbine speed on the
at T/C
turbine
inletturbine
and power
inlet.airPredictions
arePredictions
given for an
Fig.
7a.
Effect
of
power
turbine
speed
on
engine
boost
pressure.
Predictions
are
expansion ratio of the power turbine. Theoretical results are given
Fig. 7b.
Effect
of power
speedturbine
on average
to fuel ratio.
areelectr
given for an electrically turbocompounded HD diesel truck engine (black lines) and
for the same engine without turbocompounding (blue lines – standard case) at
1700 rpm and at 100%, 75% and 50% of full engine load. (For interpretation of the
references to color in this figure legend, the reader is referred to the web version of
this article.)
Limited reduction of boost pressure attributed to the aforementioned T/C shaft rotational speed decrease Rather limited especially for low PT speeds HD diesel truck HD
engine
(black
for(black
T/C turbine
inlet an
given turbocompounded
for an electrically turbocompounded
diesel
trucklines
engine
lines) and
lines
forengine
powerwithout
turbine turbocompounding
inlet) and for the same
for the
same
(blue engine
lines – without
standardturbocompou
case) at
(blueand
lines
– standard
case)
rpm and
at (For
100%,
75% and 50%
of full e
1700 rpm
at 100%,
75% and
50%atof1700
full engine
load.
interpretation
of the
references
color
in this figureof
legend,
the readerto
is color
referred
to the
web legend,
version the
of rea
load. to
(For
interpretation
the references
in this
figure
this article.)
referred to the web version of this article.)
For fixed mass of fuel injected the mass of air drawn is reduced due to the effect on boost pressure resulting into a α
curtailment for the turbocompounded HD diesel engine examined in the pres rpm and at 50%, 75% and 100% of full load. As obent study at 1700
α=m
served, the increase of power turbinea speed results in a limited
increase of expansion ratio at all loads examined. Hence, it appears
f the transformation
that the increase of rotational speed facilitates
of exhaust gas thermal energy into useful mechanical power. Exhaust gases expand to the ambience in the power turbine. Hence,
m
Fig. 8b. Effect of power turbine speed on the mean value of exhaust temperature
after power turbine. Predictions are given for an electrically turbocompounded HD
diesel truck engine at 1700 rpm and at 100%, 75% and 50% of full engine load.
C turbine expansion ratio mainly at 50% and 75% load due to engine
operation with the electric power generation system results in
Effect ofefficiency
power turbine
speed on generated
electric power.
Predictions are
reduction of Fig.
T/C9a.
turbine
compared
to conventional
engiven for an electrically turbocompounded HD diesel truck engine at 1700 rpm and
gine operation and through that, in reduction of T/C turbine generat 100%, 75% and 50% of full engine load.
ated torque and T/C shaft rotational speed (see Fig. 6 below). The
curtailment of T/C speed results in moderate reduction of charge
air mass flow rate through the pertinent reduction of boost pressure (see Fig. 7a) leading thus, to the improvement of compressor
efficiency since less shaft power is required for attaining the same
compression power.
The increase of power turbine speed results in reduction of T/C
turbine efficiency whereas, the corresponding effect on compressor
efficiency is negligible at all loads examined. Compressor efficiency
is constant and equal to 76.5%, 77% and 77.5% at 100%, 75% and 50%
engine load respectively. The maximum decrease of T/C turbine
efficiency is approximately 2% and it is observed at partial engine
load. The reduction of T/C turbine efficiency with increasing power
turbine speed can be ascribed to the reduction of T/C turbine
expansion ratio mainly at 50% and 75% load with increasing power
turbine speed.
Fig. 5 depicts the variation of power turbine efficiency with its
speed. As evidenced, the effect of power turbine speed on its efficiency varies with engine load. Specifically, the power turbine efficiency increases with its speed at full engine load. However, at 75%
Fig. 9b. Effect of power turbine speed on the percentage variation of net engine
and 50% engine load, the power turbine efficiency increases inibrake power with reference to standard engine operation without turbocompoundtially and starts
to reduceareafter
certain
value turbocompounded
of power turbine
ing. Predictions
givenafor
an electrically
HD diesel truck
engine at from
1700 rpm
100%,
75% and 50%
of fullof
engine
load.
speed. As witnessed
Fig.and
5, atthe
maximum
value
power
turbine efficiency is equal to 79%. In a following paragraph, it will be
demonstrated that the values of power turbine speed, which correspond to the maximum observed power turbine efficiency at each
examined load correspond also to the maximum bsfc reduction
(see Fig. 10 below) revealing thus, a direct relation between power
turbine efficiency and bsfc improvement.
Electric power generation and net engine power Fig. 9a. Effect of power turbine speed on generated electric power. Predictions are
given for an electrically turbocompounded HD diesel truck engine at 1700 rpm and
at 100%, 75% and 50% of full engine load.
Gains are enhanced with increasing engine load due to the higher thermal energy associated with the exhaust gases expanding in the power turbine showing different behaviors for each engine load 62 kW at 100% Maximum achieved values 39 kW at 75% 5.3. Effect of power turbine speed on turbocharger speed
23 kW at 50% Ptot = Pengine + Pelectric
The influence of power turbine speed on T/C speed is shown in
Fig. 6, where the standard case without turbocompounding is also
included. As evidenced, the application of electrical turbocompounding on the examined HD diesel engine results in reduction
of T/C speed at all loads examined. This observation can be attributed to the aforementioned reduction of T/C turbine efficiency
Significant decrease of engine power up to 15% due to the air fuel ratio reduction sp
ci
ci
a
ti
sp
b
d
sp
e
(s
tu
5
F
in
p
o
u
m
in
p
o
m
d
v
is
Effect of power turbine speed on sfc C.O. Katsanos et al. / Energy Conversion and Management 76 (2013) 712–724
721
electrical turbocompounding system compared to the standard
case (Fig. 7a), results in reduction of air to fuel ratio at all loads
examined. Hence, the operation of the proposed turbocompounding system downplays the in-cylinder air availability affecting thus
negatively the combustion efficiency.
The deviation of air fuel ratios between the case of turbocompounded engine operation and conventional diesel operation increases moderately with increasing power turbine speed at all
loads considered following the aforementioned effects of power
turbine speed on T/C turbine efficiency, T/C speed and boost pressure. The maximum reduction of air to fuel ratio with respect to
standard operational case is 2.5 and is observed at 50% load.
At all loads the positive effect of the applied turbo compounding technology on sfc is enhanced with increasing power turbine speed up to a certain point which is defined as the operating point of the turbo-­‐compounding engine Fig. 4. Effect of power turbine speed on T/C compressor and turbine efficiencies.
Predictions are given for an electrically turbocompounded HD diesel truck engine
(black lines for compressor efficiency and red lines for T/C turbine efficiency) and
for the same engine without turbocompounding (blue lines – standard case) at
1700 rpm and at 100%, 75% and 50% of full engine load. (For interpretation of the
references to color in this figure legend, the reader is referred to the web version of
this article.)
Fig. 10. Effect of power turbine speed on bsfc percentage variation with reference
to standard engine operation without turbocompounding. Predictions are given for
an electrically turbocompounded HD diesel truck engine at 1700 rpm and at 100%,
75% and 50% of full engine load.
increasing rotational speed of the power turbine. The previous T/C
speed reduction with increasing power turbine speed is higher at
part engine loads compared to the operation of the system at full
engine load. As shown in Fig. 6, the T/C speed decreases from
91.20 krpm to 88.00 krpm at full engine load. Furthermore, the T/
C speed is reduced from 83.50 krpm to 78.50 krpm at 75% engine
load and from 74.40 krpm to 69.20 krpm at 50% engine load.
According also to Fig. 6, the T/C speed increases with engine
load both for turbocompounded and non-turbocompounded diesel
engine operation. This is attributed to the increase of thermal energy of exhaust gases, which expand in T/C turbine, due to the increase of fuel injected quantity with increasing engine load. Thus,
the higher thermal energy of expanding exhaust gases increases
Fig. 5. Effect of the rotational speed of the power turbine on its efficiency.
the kinetic
energy
ofelectrically
T/C turbine
blades resulting
in anatinPredictions
are given
for an
turbocompounded
HD dieselthus,
truck engine
sfc =
5.5. Effect of power turbine speed on exhaust temperature at T/C
turbine
inlet (high-pressure
exhaust
manifold), on power
turbine
inlet
Engine load sfc variation PT speed (low-pressure exhaust manifold) and on power turbine outlet
2.1% 70 krpm Fig.
8a 5illustrates
0% the influence of power turbine speed on the
average exhaust temperature
the entrance of
turbine
at
3.6% the
85 T/C
krpm 75% turbine inlet.
and at power
Theoretical results are also given for
the mean values of exhaust temperature at the entrance of the
4.5% for diesel engine
90 krpm 100% T/C turbine,
which were considered
operation
without turbocompounding (standard case) at all loads examined.
As observed, the application of the proposed electric power
generation system results in significant increase of exhaust gas
temperature at T/C turbine inlet compared to conventional diesel
operation due to the aforementioned deterioration of air to fuel rafuel
tc The st
tio and the subsequent exacerbation of combustion efficiency.
average increase of exhaust gas temperature at T/C turbine inlet
tc
between
turbocompounding and conventional diesel
engine electrical
electric
operational mode is approximately 103.5 !C, 90 !C and 74 !C at
100%, 75% and 50% load respectively.
As witnessed from Fig. 8a, exhaust gas temperatures both at T/C
turbine inlet and power turbine inlet increase with increasing
power turbine speed at all loads examined. This is attributed to
the aforementioned deterioration of air to fuel ratio (Fig. 7b) with
P
m
+P
sf (%) =
sfc − sfc
×100%
sfc
arger on the other hand provides increasing pressure ratios as the engine speed
1050
Jacopo Dellachà et al. / Energy Procedia 45 (2014) 1047 – 1056
1050
Jacopo
Dellachà
et
al. / Energy Procedia
45 (2014
) 1047 – 1056 or too high at high speeds.
et pressure
may
be
either
insufficient
at low
speeds
1050 PT Jacopo Dellachà et al. / Energy Procedia 45 (2014) 1047 – 1056
Turbocharger Dynamic Behavior arger is more reliable; installation and maintenance are easier.
•
arger weighs less and is smaller than a supercharger,
other
things
equalλa
m abeing
Compressor : P
=
c
C
p _ aTa ( β c −1)
η
c
for the same pressure ratio and air flow rate).
EG •
o is approximately up to 3 for a turbocharger and up to 2 for •a Roots
compressor.
Turbine : PT = (m a + m f )ηT c p _ eTe (1− β Tλ )
Power electronics .
. P =0
Torque
ent response, turbochargers do not respond as fast
Fig. 1. PowertrainFig.layout.
1. Powertrain layout.
ally driven compressors (turbo
lag), due
thelayout.
time
Fig. 1. to
Powertrain
Fig. 1. Powertrain layout.
2.1. System operational logics dω
ational
logics
P2.1.
PCsystem
+2.1.PelSystem
=Jlogics
ω
( turbocharger
)
Mto
M C = J(dω ) − M el
he
exhaust
and
T −
T −generate
operational
logics
System
operational
dt
dtthis paragraph. Due
Mechanically
driven
Turbo-­‐Compound The operational logics implemented in order to optimally manage the system are described in
to
the
very
different
objectives
searched,
the
“race”
and
the
“qualifying”
configurations
of
the
system
are
al
logics implemented
inlogics
order
to optimally
manage
system
aresystem
described
this
paragraph.
Due
boost.
The operational
implemented
toseparately.
optimally
manage
the
are described
in this
paragraph.in
Due
The
operational
logics
implemented
inthe
order
to optimally
manage
thein
system
are
described
this paragraph. Due
characterized
by
different
logics and
willin
beorder
treated
to theRace
very
different
objectives
searched,
the
“race”
and
the
“qualifying”
configurations
of
the
system
are
to
the
very
different
objectives
searched,
the
“race”
and
the
“qualifying”
configurations
of the system are
erent objectives
searched,
the
“race”
and
the
“qualifying”
configurations
of
the
system
are
configuration:
The battery
SOC must be constant (within a certain tolerance) at the end of each lap.
At steady s(maximum
tate : pedal
characterized
by
different
logics
and
will
be
treated
separately.
Turbo
n,
and
compressor
load
are
the
primary
contributors
characterized
by
different
logics
and
will
be
treated
separately.
angle):
the
MGU-K
provides
to
the
wheels
all
the
power
produced
by
the
MGUFull
load
different logics and will be treated separately.
Race configuration:
The
battery
must
betoconstant
(within
certain(within
tolerance)
at the
endsoofthat
each
H. TheRace
power
flowing
fromSOC
the
battery
the
MGU-K
hasconstant
aa feedback
on the abattery
SOC,
below
configuration:
The
battery
SOC
must
be
certain
tolerance)
atlap.
theaend of each lap.
ation: Thedbattery
must
be pedal
constant
(within
a certain
tolerance)
atall
the
endwheels
of produced
each
lap.
ω Full
(maximum
angle):
the
provides
to the
wheels
by the MGUload
certain
threshold
the
logic
limits
theMGU-K
power
supplied
to
the
MGU-K.
=SOC
0SOC
(maximum
pedal
angle):
the MGU-K
provides
tothe
thepower
all the power
produced by the MGU- Naturally Aspirated
Full load
dt
partH.
of
the
vehicle
kinetic
energy
recovered
by
the
MGU-K
and
converted
into
electric
energy
is
angle):
the
MGU-K
provides
to
the
wheels
all
the
power
produced
by
the
MGUd (maximum pedal
H.Braking:
The
power
flowing
from
the
battery
to
the
MGU-K
has
a
feedback
on
the
battery
SOC,
so
that
below
a so that below a
The power flowing from the
the battery SOC,
Mbattery
− Mto Cthegroup
+MGU-K
Matelan has
Ma feedback
− M Conspeed;
Tsupplied
T rotational
directly
delivered
to P
the
MGU-H
to keep
the turbocharger
imposed
the
=
P
certain
SOC
threshold
the
logic
limits
the
power
to
the
MGU-K.
>
power
fromcompressor
the battery
toTthe
MGU-K
has alimits
feedback
onsupplied
the battery
SOC, so that below a
certain SOC
threshold
the
power
to the MGU-K.
C the
callyflowing
driven
has
a logic
faster
response
remaining part is stored in battery.
of the vehicle
kinetic
energy kinetic
recovered
by+theJ MGU-K by
andthe
converted
into
electric
energy iselectric energy is
Braking: part Braking:
Jenergy
JTCspeed
part
of
vehicle
MGU-K
and
converted
OC threshold the
logicdelivered
limits
the
power
supplied
tothethe
MGU-K.
TC
the
energy
required
tothe
keep
thekeep
turbocharger
group recovered
at elangroup
imposed
rotational
through
the into
Release:
directly
to
the
MGU-H
to
turbocharger
at
an
imposed
rotational
speed;
the
el speed is
directly
delivered
to the MGU-Htoto the
keep the
turbocharger speed.
at an imposed rotational
speed; the
otational
directly
coupled
engine’s
MGU-H
is taken
from the
battery.
part of the vehicle
kinetic
recovered
by the MGU-K
and
converted group
into electric
energy is
remaining
partremaining
isenergy
stored inpart
battery.
is
stored
in
battery.
Acceleration after a release phase: in the first phase of the transient, as soon as the gas pedal is pressed,
the energy
required
keep
the turbocharger
at
imposed
rotational
speed
through the
thespeed through the
Release:
delivered to the
MGU-H
to keep
thetoand
turbocharger
group
ananimposed
energy
is taken
from
thethe
battery
supplied totothekeep
MGU-H,
toatre-accelerate
the turbocharger
group;speed;
once
energy
required
thegroup
turbocharger
group
atrotational
an imposed
rotational
Release:
MGU-H
is
taken
from
the
battery.
the
latter
has
reached
itstaken
designfrom
speed,
the
MGU-H
can receive energy
from theimprove turbocharger group;
g partElectric is stored in
battery.
Volpe,
Macchine,
Liguori
Editore,
Napoli,
m
otor m
ounted o2011
n inthe
tthe
he turbocharger sashaft is pressed,
MGU-H
is
battery.
Time [s]
first
phase of
the transient,
soontoasthetheMGU-K,
gas pedal
Acceleration
a release
phase:
therefore, inafter
the
second
phase
the
MGU-H
provides
electric
energy
directly
which
in the
first
phase of
the transient,
as soon
as the gas
pedal is pressed,
Acceleration
after a releasegroup
phase: at
the energy
required
to
keep
the
turbocharger
an
imposed
rotational
speed
through
the
energy
is taken
from thed
battery
and supplied
to the
MGU-H,
re-accelerate
the
turbocharger
the turbo-­‐charger’s ynamics o
nly if supplied
ofthe atongular cceleration contributes
to accelerate
the
vehicle.
battery
state
charge
plays
a veryaimportant
role: in group;
fact, once
energy is taken
from theThe
battery
and
to
the
MGU-H,
to
re-accelerate
the
turbocharger group; once
is taken
from the
battery.
theaccording
latter has
reached
itsisdesign
the MGU-H
can
from
theMGU-K
turbocharger
to the
SOC, it
possiblespeed,
to provide
an increase
of receive
the powerenergy
supplied
to the
which group;
tion
Engines
the
latter
has
reached
its
design
speed,
the
MGU-H
can
receive
energy
from
the turbocharger
group;
of the econtributes
lectrically athessisted easxceeds tthe
hat f the aseline turbocharger. thein
acceleration,
byphase
taking
more
energy
from theelectric
battery.
therefore,
intothe
second
phase
theturbocharger MGU-H
provides
energyasdirectly
toopedal
the
MGU-K,
which
first
ofphase
the
transient,
soon
gas
isbpressed,
tion after
a release
phase:
therefore,
in
the
second
the
MGU-H
provides
electric
energy
directly
to
the
MGU-K,
which
Qualifying
configuration:
No
feedback
control
on
the
battery
SOC.
contributes to accelerate the vehicle. The battery state of charge plays a very important role: in fact,
s taken from the
battery
and
supplied
to
the
MGU-H,
to to
re-accelerate
theofturbocharger
once role: in fact,
contributes
accelerate
the vehicle.
The
batteryitsstate
charge
plays(120
agroup;
very
pedalto
angle):
the MGU-K
supplies
the wheels
maximum
power value
kW), important
Full
load (maximum
according to the SOC, it is possible to provide an increase of the power supplied to the MGU-K which
46
Other possible energy uses Thank you
for your attention