Prius Primer Slide Show - L. David Roper's genealogy web page

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14 Νοε 2013 (πριν από 3 χρόνια και 8 μήνες)

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Prius Primer

L. David Roper

Professor Emeritus of Physics

Virginia Polytechnic Inst. & St. Univ.

roperld@vt.edu

http://arts.bev.net/roperldavid

Toyota Prius II 2004
-
8

($21,000 to $30,000)

A serial
-
parallel (full) hybrid
(gasoline + electric) car

http://www.hybridsynergydrive.com/en/top.html

Prius 2004
-
8 Under the Hood


Engine

Generator/motor

Motor/generator

Inverter Unit

Fuse box
with
jump
-
start
terminals

4 cylinder

engine + electric motors =
6 cylinder

engine performance.

Hood
brace

Aluminum hood

Toyota Prius 2004
-
6

Motion selector

Power button

8
-
feet ladder (not included)

2005 Fastest selling car in the U.S.

Energy
-
Use
7” Display

generator/motor

Motor/generator

201.6
-
VoltsTraction battery 12
-
Volts system
-
start/accessories battery

“Key” fob slot

Prius Cargo Areas

Small
-
items storage

Back seats down

Pull up extra space cover to make room for large suitcases.

False spare tire & tools are under storage bin.

Remove storage bin to get to 12V system
-
start/accessories battery on
right side .

Cargo cover

3’ 3” by 5’ 9” long

Prius Cargo Area

Split back seat

False
spare tire
& jack

Cargo box
& tire
tools

Front tow hook.

Maps &
bottle
holder
(both
sides)

Traction Battery

Battery safety plug

Small
storage
bin

12
-
Volts system
-
start/accessories battery

Toyota Prius 2004
-
6

Motion
selector

To start hybrid system, depress brake
pedal before pressing Power once.

Smart Start option: fob can be
anywhere in the car.

Smart Entry

Also, audio.

7” Multi
-
Display


Can be turned off (Display/Screen off)


Has
daytime and nighttime settings

(dark
background).


Nighttime settings

are in effect when lights are
on, except when panel dimmer wheel is set to
maximum.


Can
save settings

for different users.


Outside temperature is shown when energy
display is active.


Several
display controls are on the steering
wheel
. Holding a button done turns on and off.


Audio and air conditioning controls can be
displayed, but some are also available on the
dash and steering wheel.

http://john1701a.com/prius/presentations/2004
-
prius_tech
-
presentation_01.htm


Rear tie down hooks; can be replaced by tow bar for rear bicycle rack.

Emissions controls

Oil filter

Oil drain

Note the flat plates to cut down on drag at high speeds.

Front of vehicle

Whats Underneath.

Toyota 2004
-
8 Prius Specifications


Engine
: 1.497 cc, 4 cyl, 16 valves, VVT
-
i, ETCS
-
i,
76 hp (57
kW)

@ 5000 rpm, compression ratio 13.0/1


Motor/generator
: 500
-
Volts Permanent Magnet rotor AC
Sync,
67 hp (50 kW)

@ 1200
-
1540 rpm


Generator/motor
: 500
-
Volts PM AC Sync,

34 hp (25 kW)
.
Starts engine at 1000 rpm when needed. Can turn up to
10,000 rpm. A crucial part of the
Electronic Continuous
Variable Transmission (ECVT)
.


Power Split Device
: fixed gears that connect engine,
motor/generator & generator/motor to provide the
ECVT
by electronic control.


Traction Battery
: 201.6
-
Volts NiMH,
38 kW (51 hp)


5 networked hybrid system computers.


Net Hybrid System power:
110 hp (82 kW)


Heated coolant when starting


Regenerative coasting and braking


Realistic Mileage:
40
-
55 mpg
(
EPA: 60 city/51 not so
)

1 hp = 0.746 kW

1 kW = 1.34 hp

Toyota 2004
-
8 Prius Specifications


Weight: 2890 lb (~$10/lb with all options.)


People and cargo capacity:
825 lbs (374 kg)


Turning radius:
17 feet

(Turns around within most streets.)


Coefficient of drag:
0.26

(Only Honda Insight is lower.)


Ground clearance: 4.9 inches (Not an SUV!)


Height/width/length: 58.1/67.9/175 inches


Electric:
reverse motion, initial motion
, climate control,
steering, braking


Interior:
size of Toyota Camry


Exterior:
size of Toyota Corolla


12
-
Volts battery to start system & for accessories


Tires: P185/65R15 Goodyear Integrity (
low snow traction
)


11.9 gal =
450
-
500 miles per tank


Uses 87 octane gasoline with up to 10% ethanol


0
-
60 mph in 10.1 seconds


Top speed: 103 mph

Toyota 2004
-
8 Prius Specifications


Air bags: 2 standard; 4 more as extras


Energy
-
use, climate control and audio 7” display


Tilt steering wheel


Warranty: Basic: 3 yrs/36 kmi;
Hybrid system: 8 yrs/100
kmi
; Power train: 5 yrs/60 kmi; Rust
-
through: 5
yrs/unlimited mi; Accessories purchased with car: 3
yrs/36 kmi. Road side assistance and hazard insurance: 3
yrs/36 kmi


Excellent navigation system and wireless
Bluetooth
phone

connection as an option


Seats are cloth or leather. Toyota has seat covers that are
easy to install, with 2 map pockets for each front seat.
(2006 model offers leather seats.)


Classified as a
mid
-
sized car
.

Standard Features ($23,000)


Micron
-
filter 201V electric air conditioner


Power windows and door locks


Heated outside mirrors and rear window


Remote keyless entry


Cruise control


6
-
speaker AM/FM/CD stereo


Anti
-
lock brakes with electronic assist


Traction control


Multi
-
stage dual front air bags


Illuminated sun
-
visor mirrors


Self
-
leveling headlights


Much storage space for small items.

Optional Features ($30,000)


Front side and
roll
-
sensing curtain air bags

(front & back)


Intermittent rear window wiper


Key
-
less entry & start system (
Smart Key
)


Vehicle stability control
(Automatically controls brakes and
hybrid system to prevent skidding when cornering on a slippery
road or turning steering wheel abruptly. There is a slip
-
indicator
icon in dash display.)


High
-
intensity discharge headlamps


Integrated fog lamps


Homelink
remote transmitter

on
auto
-
dimming

mirror


9
-
speaker AM/FM/Cassette/6
-
CD stereo


Immobilizing security alarm


Floor and cargo mats; cargo net


DVD
Navigation system

with voice activation


Bluetooth wireless telephone connection

How Does It Achieve Fuel Efficiency?


Because of
electric motor assistance
, the
engine can
run at peak efficiency more often
.


Electric motors are more efficient

than gasoline
engines over a larger range of rpm.


The
high voltage (500 V)

for the motors/generators
cuts down resistance loss.


Deceleration and braking
recharge the battery
.


The
engine shuts off

when not needed; for example,
at stops and down hill. It then instantly restarts when
needed.


The
engine receives hot coolant before starting
,
which enhances efficiency.
Starts at 1000 rpm
.


The body is
aerodynamically designed

for low drag
(0.26 drag coefficient).

Aerodynamics Underneath

http://privatenrg.com

Air Flow Around a Prius II

Location:
Minnesota
. Mix of
city, suburban & highway

driving.

http://john1701a.com/prius/prius
-
data10.htm

2004 Prius mpg Versus Month of Year

12 mpg difference between
January and June driving in
Minnesota. I guess 6 in
Virginia.

Total Cost of a Prius


The Prius hybrid system has
no clutches or friction bands to wear
out
, contrary to the case for a gasoline car. There is nothing in the
hybrid system to wear out except gears and bearings.
The hybrid
system should last for at least 500,000 miles

if properly maintained.


The
engine is not stressed

nearly as much as one is in a gasoline car.
So, the
engine should last for over 200,000 miles

if properly
maintained.


The electric motors are brushless designs, so
they should last for
500,000 miles

if properly maintained.


Regenerative braking
greatly delays brake pad and rotor wear
. So,
the
brakes should last for more than 100,000 miles
.


So, cost effectiveness of driving a Prius
is as much due to the
longevity of the hybrid system, the gasoline engine, the electric
motors and the brakes as it is due to higher mpg
.


As important as high mpg is the low emissions of a Prius compared
to any gasoline car. High mpg for a gasoline car does not equate to
low emissions. A gasoline car optimized for low emissions usually
has high mpg, but it sacrifices performance.
Performance is not
sacrificed in a Prius.

How Does the Prius Achieve Low Emissions?


Since it
uses less fuel
, it produces less emissions.


Because of electric motor assistance, the engine can
run
at peak efficiency
more often, which makes emissions
lower.


The
engine design

(Atkinson cycle, cylinder shape, fuel
injection and variable firing timing) is aimed at low NO
x

emissions.


The
engine shuts off

when not needed; at stops and
going down hills. It then instantly restarts when needed.
This reduces emissions.


The
engine receives hot coolant before starting
, which
reduces
NO
x

emissions.


Has
bladder
-
lined gasoline tank

to eliminate escaping
fumes. (Makes it difficult to manually calculate mpg.)


Has lowest emissions rating of any gasoline vehicle.

Bladder
-
Lined Gasoline Tank


Gasoline tank has a
plastic bladder liner
, which
expands and contracts as gasoline is added and used.
This minimized evaporative losses into the
environment.


The bladder can become less flexible in cooler
weather, which will keep you from putting a full 11.9
gallons in the tank.


The bladder makes the fuel gauge
(“guess” gauge
)
not very accurate. Always refuel when or before the
last marker shows on the fuel gauge.


Filling a nearly empty tank with less than 3 gallons
will not register on the fuel gauge.


http://i50.photobucket.com/albums/f322/fixmyset/refueling.swf

http://www.toyota.co.jp/en/k_forum/tenji/pdf/pgr_e.pdf

Drive it
another
100,000 kms
and watch
these
differences
grow.

Based on 10
-
years use and
100,000 km
(62,000 miles).

Prius Life
-
Cycle Carbon Dioxide Emissions

1 km = 0.62 mi: 20,000 km = 12,400 mi; 100,000 km = 62,000 mi

http://www.toyota.co.jp/en/k_forum/tenji/pdf/pgr_e.pdf

Toyota Prius 2004
-
2005

A series
-
parallel full hybrid (gasoline + electric) car

The
power split device
(PSD)

can be regarded
as an
asymmetrical
differential
, for which
the two
motor/generators are
analogous to the two
wheels that connect to
a
conventional
differential

and the
engine is analogous to
the crank shaft
(reduction gears in the
Prius) going into a
conventional
differential
.

http://www.ecrostech.com/prius/original/PriusFrames.htm

DC

AC

AC

AC
-
>DC

DC
-
>AC

AC
-
>DC

DC
-
>AC

Engine shaft
goes through
MG1 shaft to
the planetary
carrier of the
PSD.

Toyota Prius 2004
-
5 Power System

Power
-
split device

Prius Power System

http://www.privatenrg.com

Large
motor/
generator



Power Split
Device

Small
generator/
motor

Toyota Prius 2004
-
5 Power Split Device

Power Split Device
:
78

teeth in ring gear,
30

teeth in sun
gear, 23 teeth in each planet/pinion gear. (Also called
planetary gears
,
epicycle gears

and
trans
-
axle
.)

http://homepage.mac.com/inachan/prius/planet_e.html

Prius Power Split Device (PSD)

Sun gear:

MG1

Ring gear:

MG2 & Wheels


Planet/pinion
gears

Planetary carrier:

Engine

Notice how small it
is!

Effectively, this and
the electronics
comprise the
continuously variable
“transmission” of the
Hybrid Synergy Drive.

Toyota Prius Hybrid Synergy Drive Control

This contains the DC/AC
inverters. Notice the
orange
power cables

to the traction
battery and to the
motor/generator and the
generator/motor.

The 5 computers are located at
different places in the car. It is a “
drive
by wire
” system similar to modern
airplanes.

Effective Hybrid Transmission


The Prius does not have a "true" transmission,
instead the
gear ratios are fixed
. One can accelerate
from zero to the maximum speed in one gear;
however
engine torque is not multiplied by a
transmission
. This lack of low
-
end engine torque is
replaced by a large electric motor/generator and a
smaller generator/motor, which are connected to the
engine in a planetary gear arrangement (Power Split
Device).


The
onboard computer shifts power from the engine
and to and from (using the traction battery’s power)
the motor/generators
, determining the most
efficient use of the engine and/or the electric
motor/generators based on driving conditions,
accessories in use and when to charge the battery.

Movement of Power
-
Split Device Gears

Moving in Reverse

Starting Engine at Rest

Accelerating & Hill Climbing

Cruising

Coasting & braking

Two cases
when the
engine is not
running
.

2004
-
5 Toyota Prius 201.6
-
Volts Battery

Under the backseat with cooling vent beside the seat.



28 sealed modules of six
NiMH

1.2
-
Volts cells per module. 6.5 Amp
-
hours.



Weighs
86 lb

(39 kg). Highest output per weight in the world (1300 W/kg).



Charge ranges from
40% to 80%

of maximum, usually 50% to 70%.



Alkaline electrolyte is
a gel that will not leak, even in a collision
.



Sealed in a steel case electrically isolated from battery terminals.



Each module is
vented underneath

in case of overcharge gas release.



All components are
recyclable
.



Incentive of $200 for each battery returned for recycling.



Guaranteed for
8 years or 100,000 miles

(10 years/150,000 in California).

Battery safety plug/fuse

1.31 kWh

Prius Battery Module & Safety Plug/Fuse



Note the six NiMH 1.2 Volts
cells.



Note the electrical
connectors on the ends.



Note the overcharge gas
vent at the bottom left.

Battery safety
plug and fuse

http://www.peve.panasonic.co.jp/catalog/e_kaku.html

Charging the Battery at Rest


Stop the car and set the parking brake firmly.


Firmly press the brake pedal.


Set the motion selector to “D”.


Press the accelerator pedal most or all of the way down.
(Only the small generator/motor is charging the battery,
since the large motor/generator is at rest with the
wheels.
This is the reverse of starting the engine at rest.
)


The battery will be fully charged in about 5 minutes or
less.


You might want to do this before climbing or at a rest
stop on a long, steep hill for which the battery eventually
will run out of charge and, thus, does not supply power
to the motor.

Prius 12
-
Volts Battery




Turns the hybrid system on by actuating contact relays.


Provides power for the five computers and the networks in the car.


Provides power for the accessories.


Charged by the traction battery. Can be jump
-
started by other 12
-
Volts batteries
by using
terminals in the fuse box under left side of hood
. (When jump
-
starting
other vehicles, best to charge the other battery from the Prius battery, disconnect
the jump and then start the other vehicle.) If the 12
-
Volts battery becomes
discharged, you cannot move the Prius with its front wheels on the ground,
because it is in PARK.


Will gradually discharge when car is dormant. Decrease the discharge by
turning
off the smart
-
key switch

under the steering wheel. For longer dormancy periods
use a
BatteryMINDer

(
https://www.batteryweb.com/batteryminder.cfm
) or
disconnect the cable from the positive jump
-
start terminal in the fuse box on the
right under the hood (and lose memory settings). You can buy a VW solar battery
charger on eBay for parking the Prius outside for long periods.


Batteries maintenance:
http://www.vfaq.net/docs/TSBs/PG007
-
03.pdf

Locations of Prius Batteries

This is a
wrecked
Prius that
will be
shown in
more detail
later. Notice
the
orange
power cable

on the left
side and the
small 12
-
V
battery at
the right
rear.
There
are
connections
for the 12
-
V
battery
under the
hood for
jump
starting.

Traction
battery

Battery
cooler

http://www.autobeyours.com/05%20Prius.htm

Prius Gasoline Engine


1.497 cc, 76 hp (57 kW) @ 5000 rpm, 82 lb
-
ft (111 N
-
m) @
4200 rpm, 4 cyl, 16 valves, VVT
-
i=Variable Valve Timing
-
intelligent, ETCS
-
i=Electronic Throttle Control
-
intelligent,
compression ratio
13.0/1


Aluminum alloy


Atkinson/Miller cycle:
short compression stroke

(Valves do not
close until after the end of expansion stroke.)


Offset crank shaft

allows straight down power stroke.


3 liters of
Heated coolant

stored near boiling point for 3 days
used to preheat the engine before starting.


Engine
stopped at precise point in cycle

to minimize stress
when restarted.


Engine is cranked to
1000 rpm

and oil pressure established
before spark is applied first to 2 of the 4 cylinders. This takes
about ½ second.


Variable valve timing

to optimize efficiency.


Unique air intake system to
reduce manifold friction
.

2004/6 Prius Gasoline Engine

http://www.privatenrg.com

http://www.toyota.com/html/hybridsynergyview/2005/fall/mpgs.html

http://www.cleangreencar.co.nz/page/prius
-
petrol
-
engine

Prius Power vs rpm

Small motor extends to 10,000 rpm.

One can see
why the
electric
motor is
important
for power at
all,
but
especially
low
, rpm.

Prius Power Train Performance

When Does The Engine Run?


To move the vehicle.


To charge the traction battery.


To warm up for lowest emissions.


To provide heat for passengers if needed.


To power the air
-
conditioner compressor if
needed.


To run hybrid
-
system diagnostics.


Prius misconceptions:


http://john1701a.com/prius/prius
-
misconceptions.htm

Smooth Acceleration

Regenerative Braking

ECB =
Electronically
Controlled Braking System

which controls the
coordination between
friction braking and
regenerative braking, which
preferentially uses
regenerative braking.
Recovers up to 90%? of the
possible recoverable
energy down to 7 mph.
Each wheel’s brake is
independently controlled
electronically. Hydraulic
backup brake control is on
the front wheels.

To “B” or not to “B”

The
“B” selection

on the motion selector
causes the engine to
turn without firing
, using air compression and engine friction to
turn some of the vehicle’s motion energy into heat. Some of the
motion energy still goes into charging the battery, but not as
much as when “B” is not selected. (After using “B” you will need
to reset the cruise control.)
When might one use “B”?
:

Be sure to move
the motion
selector back to
“D” after using
“B”, or you will
decrease the mpg
for normal driving.


When the battery is fully charged:
all battery
bars are green

and you want to slow down.


When a sign says “
Trucks use low gear
”.


When
going down a steep hill

and the cruise
control cannot hold the car to less than 5
mph above the speed setting.

B = engine braking.

Constant Driving in B


Some owners of Prii drove all the time in B. I
know of two examples of this.


They complained that the mpg was low.


The reason is that the engine spins at high
rpm, without firing, going down hills and
when braking, instead of turning off.


It is an easy mistake to make, since the B
position is straight down from the rest
position of the movement selector. One has to
move it to the left and then down for D.

Towing a Prius


Do not leave the front wheels on the ground when towing if hybrid
system is not on and in neutral.
Doing so could damage the hybrid
system.


Towing hook for front is in cargo storage box;
screw it into covered
hole in front bumper
.


Best to use a flat
-
bed tow truck and
raise the front wheels before
pulling the Prius onto the truck
.


Two tie
-
down hooks are under the back
,
do not use them to tow
the Prius from the back
. Can be replaced by a tow bar for a bicycle
rack.


Do not allow towing or tie
-
down chain attachments to car frame;
always use the front tow hook and the back tie
-
down hooks
!


If it must be
towed with front wheels on ground
, turn on hybrid
system and put hybrid system in “N” and have someone guide it
and work the brakes.


Towing by Prius: should not be done! (Some have towed small
trailers with a tow bar.)

Towing a Prius

Best way to put a Prius in Neutral to tow it with
all wheels on the road:


Press the power button twice without
pressing the brake (IG ON mode).


Put foot on brake and shift into Neutral.


Hold
the motion selector in Neutral for 3 seconds.


Then it can be towed with the wheels on the
road.

Prius as a Powerful Computer Network


There are many Local Area Networks (LANs) connecting 5
computers in the vehicle. (All new vehicles have powerful
computers and networks; hybrids take that one giant
step further.)


The LANs communicate through super networks. E.g., the
climate
-
control network and the braking network
communicate with the power
-
train network.


For the
keyless entry & start option
, the vehicle’s main
computer powers up using the 12
-
Volts battery when you
approach the vehicle. When you press the
Power button

the other computers and LANs are turned on, powered
by the 500
-
Volts traction battery.


Pressing on the accelerator activates the motive
networks according to the movement selection.

Prius as a Powerful Computer

ECU = Electronic Control Unit = 32
-
bit computer

See
http://www.hybridcars.com/computer
-
control
-
systems.html

and

http://techno
-
fandom.org/~hobbit/cars/bodyecu

SOC = State of Charge of traction battery

What Happens When Your Press on the Accelerator?

1.
The motive power demand from depression of the accelerator
pedal (not the "throttle") goes to the Hybrid
-
ECU.

2.
The Hybrid
-
ECU also gets power demand from the battery
-
ECU
("charge me" or "discharge me"), the air conditioner, etc.

3.
The Hybrid
-
ECU decides where to get this power from, the ICE or
the battery. If it wants power from the ICE, it sends a power
demand to the Engine
-
ECU.

4.
The Engine
-
ECU figures out how to get that much power from
the ICE at the best efficiency and tells the Hybrid
-
ECU its choice
of spin (torque) so that MG1 can be controlled appropriately.

5.
The Hybrid
-
ECU controls MG2 to add or subtract power at the
final drive as necessary.

6.
Electrical power generated or consumed by MG1 and MG2 will
result in a net surplus or deficiency that is provided or absorbed
by the battery. In theory, this will correspond to the battery
-
ECU’s charge demand (see 2 above) but in practice there is much
lee
-
way for things to come out differently and other power
demands still to be met exactly. In a sense, the battery makes up
the error.

15 Computers in a “Loaded” Prius

1. HV ECU High Voltage ECU This is the brains of the HSD receiving and sending signals from all parts of the HSD turning driver
request (shift, accelerator, break) into action by parts of the HSD system.
2. ECM Engine Module controls the ICE (spark, fuel injection, valve timing etc) delivering the proper amount of power to the
system under direction of the HV ECU and informs HV ECU of ICE state.
3. Transmission ECU after receiving On signal from HV ECU monitors the Parking Switch (button) and when pressed it locks the
hybrid trans axle and locks when brake is pressed and car is placed in D, R, N
4. Skid Control ECU Controls regenerative brake effect by MG2 and the hydraulic system to mimic a conventional hydraulic
system as well as functions of Brake Assist, ABS (Antilock Brake System) and VSC (Vehicle Stability Control)
5. ECB ECU = Electronically Controlled Brake integrated into the Skid control ECU to calculate required brake force based on
peddle effort and force.
6. EPS ECU = Electronic Power Steering ECU controls the power assist to steering column calculated from input from the Skid
Control ECU and various sensors
7. Battery ECU monitors the SOC (State Of Charge) and battery temperature communicates with the HV ECU and controls the HV
battery cooling fan.
8. Power Source Control ECU Controls the push button start system receives signals from switches and ECUs communicates to
the HV ECU power on power off
9. Air Conditioning ECU calculates the compressor speed based on input from sensors using a nonlinear fuzzy logic system
controls blower speed
10. Meter ECU Transmits vehicle speed signal, receives information if smart key is in vehicle and sound the warning sound in car
on request of other ECUs (the source of the annoying beeps)
11. Body ECU receives door lock and unlock request and monitors if smart key is in vehicle transmits this to Smart ECU over a
serial connection.
12. Transponder ECU Controls the HV immobilizer by recognizing the key ID code also works with Smart ECU in cars equipped
with SKS. Transmits an HV stat authorization to the HV ECU
13. Smart ECU Checks ID code received from wireless transponders in the car and transmits the code to the Transponder ECU
14. Navigation ECU provides navigational features as well as Voice recognition and Bluetooth connection.
15. Gateway ECU provides communication between the 3 LANs (Local Area Network)
Prius Safe Computer “Hacks”


Turn off the backup beeper:


Cycle ODO/TRIP, stopping on ODO.


Power off.


Power on, within 6 seconds, hold ODO for at least 10 seconds.


While still holding ODO shift into Reverse and back into Park.


"b
-
on" shows on display, press ODO to cycle to "b
-
off".


Allow
navigation destination parameters
to be set while moving:


Press the "Menu" button (hardware button).


Press the "Voice" icon on the display.


Press the upper left corner of the display, where the speaker icon is.


Press the lower left corner.


Press the upper left corner again.


Press the lower left corner again.


The screen should change to a diagnostic screen.


Hold the "Override" button for several seconds until it changes to black
and a beep is heard.


Press the “Back” button.


This will be in effect only until the Power is turned off.


Warning: do not play with things on this screen that you don't know
about!

Prius Electric Safety


Battery is placed between the frame rails and in front of
the axle
where it is least likely to be damaged in an
accident
.


High
-
voltage cables are
metal shielded, orange colored

and placed away from possible damage in collisions.


Battery power is
cut off when an air bag deploys
and
other collision sensors activate.


Vehicle does an electric system check when powered up.


Toyota provides
special pamphlets for emergency
personnel
:
http://techinfo.toyota.com/public/main/2ndprius.pdf


See
http://www.asashop.org/autoinc/april2004/collision.cfm

http://www.asashop.org/autoinc/aug2002/special.cfm


See
http://autos.groups.yahoo.com/group/toyota
-
prius/message/8834

for information about the
difficulty
of getting shocked by a Toyota Prius
.

Prius Electric Safety

A ground
-
fault
monitor keeps the car
frame from being
accidentally charged.

Battery shut
-
off
relays.

Fused safety plug:
Pulling it out turns off
the high voltage.

Hybrid Reliability


Consumer Reports listed
Toyota Prius

and
Honda Civic hybrid

among the most
reliable vehicles for 2005 models.


Toyota Prius traction batteries regularly last for over
200,000 miles driving. Should
last 15 years.


The Toyota Synergy Hybrid System is much simpler mechanically than gasoline
vehicles (no transmission). The complexity is in the electronics, which is highly
reliable.


Engine does not always run, standard brakes are not always used for stopping and
there is no starter or alternator to wear out. Brakes should last 100,000 miles.


Early 2004
-
5 Toyota Prii had a software problem that caused the engine to stop.
(EV still worked to move vehicle.) A software download fixed the problem after 68
known incidents of engine stalling.

http://news.yahoo.com/s/ap/20051013/ap_on_bi_ge/prius_recall_1


http://home.comcast.net/~bskattebol/50p.pdf


http://www.earthtoys.com/emagazine.php?issue_number=05.08.01&article=naftc


The
modular design

of the Toyota Prius allows defective modules to be quickly
diagnosed and replaced.


Prius Maintenance:

http://john1701a.com/prius/prius
-
maintain04.htm


http://www.artsautomotive.com/Hybrid.htm


Car Talk Prius excellent review:


http://www.cartalk.com/content/testdrives/Reviews/toyota
-
prius
-
2004.html

I have had one 2005 Prius recall to replace the steering column.


Prius I Engine Efficiency

http://techno
-
fandom.org/~hobbit/cars/prius
-
curves.gif

Peak efficiency is at
about half power. The
“sweet spot”.

1500 rpm 2200 rpm 3000 rpm

Better to floorboard than to creep!

Worst efficiency is at low power.

http://john1701a.com/prius/presentations/prius_ths
-
presentation_07.htm

Differences in Driving a Prius


Power

button starts the hybrid system, rather than a key. The
“key” fob must be somewhere in the car for “smart start”
option; in the fob slot otherwise.


Engine does not start immediately after system power is
turned on; it
starts about 7 seconds later to warm up the
engine
, then shuts off a few seconds later if not needed.


Engine
turns off at stops and when going down hills; also it
does not provide power for backing up
.


Creep

is built in at stops, provided by the electric motor. It is
increased on an upward and downward slope to hold car in
place. It can be turned off by pressing the brake pedal or
putting the movement selector in the
N
eutral position.


Slight sounds occur after stopping the car as hot coolant is
pumped into the thermos container.


Electric whine during slows starts and braking.


Special
B
rake position of movement selector to cause engine
braking.

How to Drive a Prius Efficiency


Use “Pulse Driving”:


Accelerate rapidly at about half power
, because a brief medium
engine load uses less fuel than a prolonged low engine load.
Best is
when only the engine is moving the vehicle.


Decelerate slowly

well ahead of the stopping point to maximize
brake regeneration.
Best is when neither engine nor motor is
moving the vehicle and the battery is not charging (gliding).


Keep the vehicle in a garage during cold weather because a cold
vehicle reduces brake regeneration.


Keep tire pressure at recommended levels or higher to reduce tire
friction losses. I up them by 2 psi.


Steady 55 mph (55
-
60 mpg) is the point of peak efficiency. 75 mph: 40
-
45 mpg.
For every mph faster than 55 mph, fuel economy drops by
about 1 percent.


http://home.earthlink.net/~graham1/MyToyotaPrius/Driving/Economy.htm

Driving for Lowest Emissions and Highest MPG


MPG is much lower for the first 5
-
10 minutes of
driving, because the engine is run until it reaches
the best temperature for the lowest emissions.
So, combine short
-
trips to save gasoline.


MPG, as for all new cars, increases as the miles
are driven up to about 10,000 miles.


Higher tire pressure=higher MPG. Maximum
pressure for the tires=44 psi. (Standard=35
front/33 back) Should be 2 psi greater in front
than in back. I use 38/36; many use 42/40.


Use cruise control when possible to get best
MPG.

MPG versus MPH for 2003
-
8 Prius

Note the big decrease in mpg above 70 mph!