This document discusses hybrid vehicles and the author's 2007 Toyota Camry Hybrid. It provides an overview of hybrid technology including the Toyota Hybrid Synergy Drive system. The author describes various trips taken in their Camry Hybrid, noting factors like warm-up time and miles per gallon achieved. Potential future fuel sources for hybrids like solar panels and heat panels are also examined. The document concludes by discussing features the author would like to see in future hybrid vehicles.
18. Where do we go from here?: What I would like to see? What about you?2 Why it's fun to drive a hybrid 2007 Toyota Camry Hybrid My Car Model 2010 Toyota Camry Hybrid Taxicab
19. Propulsion Concepts Propulsion System: the source of motion of a vehicle including its fuel tank. Why it's fun to drive a hybrid 3 Passenger Compartment Motor Fuel Tank Multi-engine vehicle: More than one motor: e.g. airplanes. Passenger Compartment Motor Fuel Tank Motor Hybrid: an ensemble of motors using different fuels, possibilities! Gasoline-electric hybrid: principal gasoline propulsion system assisted by a secondary electric propulsion system. Passenger Compartment Gas Motor Gas Tank Battery Electric Motor
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21. Brake override to allow driver response to Sudden Unintended Accelerations (SUA)
23. Electric air conditioner with ECO feature to increase fuel economy; two electric heaters are added to engine heat exchanger to heat the cabin with the ICE off.
24. Aerodynamic drag coefficient, Cd, 0.27 where 0.24 is that of the best of cars, M. Benz E class Coupe and 2.1 for a smooth brick!
38. Difficult to quantify because of computer introduction, 15% improved acceleration measured.
39. Electronic Continuously Variable Transmission (e-CVT) ties all components together mechanically enabling full computer control sophistication.
40. Emergency battery and starter motor in case the HSD battery pack is fully depleted after a long idle hiatus.Why it's fun to drive a hybrid Toyota Hybrid Synergy Drive (HSD) 6
56. Motor forward needed to go uphill, but battery is empty, the ICE can’t make the car go any faster
57. Generator reverse for regenerative braking with power stored in the hybrid battery provided by computer firmware
58. Drive shaft to wheels connected to outer ring of planetary gear set of ECVT
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60. Why it's fun to drive a hybrid 9 HSD Operational Phases Engine Start: apply power to MG1, while stopped or moving; power can originate from starter battery and emergency starter motor directly on the ICE. Low Gear (equiv.): Rapid engine speed, low torque, some speed is fed to MG1 in generator mode which powers MG2 in motor mode supplying needed torque. High Gear (equiv): ICE generating more torque than needed, MG2 switches to generator mode, power is directed to MG1 in motor mode to power wheels. Reverse gear: negative voltage to MG2 with some ICE if needed if backing up hill. Stealth mode: electricity supplied only to MG2, MG1 rotates freely with open circuit. ICE can be turned off. No gasoline is used. Energy if that stored in battery from prior high gear operations. Neutral gear: both motors are off. ICE will turn off as soon as the battery pack is fully charged. Regenerative Braking: MG2 is a generator charging the battery pack which dissipates energy from the drive shaft. Conventional brakes can be smaller and undergo significant life increases with careful driving. Compression Braking: MG2 is a generator, power is directed to MG1 speeding the engine with throttle closed which absorbs the energy. Electric Boost: A portion of the battery reservoir is managed by an optimal load curve in addition to the torque management mode. This provides extra energy when unexpected demands occur. Battery Charging: ICE runs and MG1 as a generator directs power to the battery pack. This keeps the air conditioning operating when the car is stopped, because there is no serpentine belt.
61. Why it's fun to drive a hybrid 10 HSD Operational Summary
124. What would I like to see in cars of the future? Features that reduce driving distractions Radios that record automatically when I use the display. Combat driving fatigue Multi-modal cruise controls : normal, pulse and glide, … Web browser built-in that allows macro definitions User control by options specification with detailed usage guides on websites devoted to the models Replace “Energy Display” with more technical multi-tab spreadsheets Plug-in should warm up the ICE for a particular departure time and charge the battery pack! What would you like to see in high-tech cars of the future? . Why it's fun to drive a hybrid 25 Where do we go from here?
Editor's Notes
My gasoline – electric hybrid is loads of fun to drive.Some folks drive hybrids to make a statement about their carbon footprint; not me.I drive mine because it is a tech marvel; I have always been an early adopter. I felt that I needed to support the high technology industries in which I worked.Learning to get onboard with hybrids is a good step to take for thoughtful individuals. Many energy improvements will develop to support hybrid vehicles.My resume is laced with high-tech experiences in both science and software engineering. I am a graduate from UC Berkeley in Chemistry and the University of Hawaii again in Chemistry. I eventually finished a Ph.D. in Mass Spectrometry from the University of Geneva, Switzerland. I worked for 30 years in embedded firmware and robotics. I am now retired.
Up until recently, driving a hybrid car required some sort of sacrifice, whether it be space, performance or anonymity. However, with the introduction of the Camry Hybrid, one could argue that Toyota has given the buying public a hybrid that demands no sacrifices.If judged only on its merits as a competent (if not superior) midsize sedan, the Toyota Camry Hybrid would score well. We've found that it shares all the attributes that makes the conventional Camry one of the best family sedans out there: a comfortable cruiser, more than adequate power, a top-notch interior, lots of amenities and plenty of room for five. The hybrid model costs just $1,500 more than the gas-only Camry. It gets at least 15% better gas mileage. 15000/30 orthat its fuel economy betters that of most gas-only compact cars (including Camry). and is priced well within the normal range for an average car is icing on the hybrid cake.As its name implies, the Toyota Camry Hybrid is a regular Camry sedan with a gasoline-electric hybrid power-train. The hybrid system is comprised of a 2.4-liter four-cylinder gasoline engine (producing 147 horsepower and 138 pound-feet of torque) and a 45-hp electric motor. The Camry Hybrid can run on any combination of the two power sources.Power is transferred to the front wheels via a continuously variable transmission (CVT). The CVT was chosen for its ability to keep the gas engine in its most efficient power band. We found that the Camry Hybrid's combination of the gas and electric motors felt surprisingly robust. Acceleration betters most four-cylinder sedans and is not far behind many six-cylinder ones.Since the gas engine of the Toyota Camry Hybrid will shut down at a stop and under some driving conditions, the air-conditioning and power-steering systems are driven electrically and powered off of the vehicle's batteries. This maximizes fuel economy and guarantees that the air-conditioning will continue to operate.Those consumers considering the purchase of a Toyota Camry Hybrid should be aware that it does cost more. Compared to the similarly equipped four-cylinder Camry XLE, for instance, the Hybrid costs approximately $1,500 more. The Hybrid is also a bit deficient in terms of luggage space -- trunk capacity drops from the regular Camry's 15 cubic feet to 10.6 due to the space taken up by the battery pack.
Propulsion System: the source of motion for a vehicle having a motor and its fuel storage system.Multiengine Propulsion System: Two or more motors and their fuel storage.Two or more motors can be the same: Airplanes have more than one engine.Different kinds of motors in a propulsion system makes it hybrid.If one of the motors and fuel storage systems is electric, then the vehicle is hybrid electric.Fuel storage for liquid fuels is a tank.For electricity storage is usually a battery.Storage that converts mechanical energy to electricity could be a flywheel.
Hybrid Synergy Drive (HSD) – The left side (black) is a 1.5 liter Internal Combustion Engine which both drives the wheels and the electric generator. The right side (silver) is the high voltage unit as part of the Toyota Hybrid Synergy Drive on a 2004 Toyota Prius.HSD Cutaway – Toyota Showroom in Paris, Date 7/4/2006High Voltage Inverter Unit – The THS high voltage inverter unit. After the silvery cover is removed, the guts of the high voltage inverter unit is revealed. This particular inverter is the one used in the NHW11 "Classic" model of the Prius. The 3 black cylinders are capacitors.MG1 – Motor generator used as generator to charge Hybrid battery.Internal Combustion Engine (ICE) – Gasoline engine of the HSD.MG2 – Motor generator used to add electric drive to the drive train after the planetary gear.SCR – Planetary gear assembly (transmission) transmitting power from ICE to drive train to add to the power of MG2.
Link to 60 Minutes documentary on Bloom Energyhttp://www.cbsnews.com/stories/2010/02/18/60minutes/main6221135.shtml
Motor not cold, not the first trip of the day, city streets, average speed is 36 miles per hour, 10.7 miles covered in 18 minutes, the consumption averaged 44 miles per gallon with first minute being 21 miles per gallon and ending with 60+ miles per gallon. It took 11 minutes (warm up period) to get to optimum consumption, remaining there for 7 minutes. Over a 10.7 miles trip, the car burned 1 quart of gasoline. The ratio of warming-up periods to already warm periods is critical to the overall efficiency that one experiences. A trip that gets more than 35 miles per gallon is deemed excellent by the control computer. Geeks love that, me included!
Motor not cold, not the first trip of the day, city streets, average speed is 36 miles per hour, 10.7 miles covered in 18 minutes, the consumption averaged 44 miles per gallon with first minute being 21 miles per gallon and ending with 60+ miles per gallon. It took 11 minutes (warm up period) to get to optimum consumption, remaining there for 7 minutes. Over a 10.7 miles trip, the car burned 1 quart of gasoline. The ratio of warming-up periods to already warm periods is critical to the overall efficiency that one experiences. A trip that gets more than 35 miles per gallon is deemed excellent by the control computer. Geeks love that, me included!
First leg of day trip: To bowling alley for practice.
Took 11 minutes to warm up. Bowling to a social club meeting. The final leg of trip is next 2C.
Social club to home finalizes the day’s trip. This level of car usage is 600 miles per month. Gallons per month are 30*0.63 or 18 gallons per month. A cold Camry in normal driving would do well to get 20 mpg on such short trips. This version of Camry saves about 10 gallons of gas every month or $30 per month, $360 per year. In 5 years the hybrid system saves it’s cost. Brakes wear out much less due to regenerative braking protecting the brake pads. Probably 2 brake jobs will be avoided during the life of the car.
After charging the battery very well, electricity is used instead of gas, yielding nearly infinite gas mileage. The 99+ consumption is an indication. The episode is just 3 minutes long. It can be quite long with meticulous gliding (subsequent slide).
Enthusiasts in Japan have hacked their Priuses, and use zen-like driving techniques to get up to 116 miles per gallon (they go 1000 miles on a 13 gallon tank of gas). In Japan they are called "nenpimania", Japanese for "mileage maniacs". Their techniques involve hacking the cars' computer systems, adding special tires, strategically placing tap, cardboard and foam rubber over the engine and grill. They also drive barefoot, and strive to perfect what they call the "pulse and glide" driving method, which requires sensitivity when pushing or releasing the accelerator. Some drivers use only their big toe to push the accelerator. :: Via The Raw Feed and Chicago Tribute. (Note: Photo shows American, not Japanese, Prius hack.)The Raw Feed Where technology and culture collide
http://www.metrompg.com/posts/pulse-and-glide.htm
Obey the speed limits: If you're not in a hurry and not impeding traffic by doing so, stay a bit underthe limit. You should notice the difference right away. If traffic is moving faster than you'd like, find a vehicle that is traveling at a moderate speed and follow it. Not too closely, please; drafting is dangerous. Drafting is when you try to let another vehicle suck you along in its wake. Race drivers do it to save fuel when they must follow the leader.Accelerate thoughtfully: Take it slow. Imagine that you're on a residential street. You have a chance to keep the vehicle in EV mode, under 20–25 mph. Conventional thought says that getting off the mark gently and getting up to speed gradually is the way to save the most fuel. But that is with a conventional propulsion system. Hyper-milers (see next slide) driving a hybrid propulsion system (liquid fuel with electric motor blended) believe that being a bit aggressive on start-up yields better mileage than using a slow acceleration. Choose your personal method using the mpg-meter as your guide. Whichever method you choose to practice (timid or aggressive acceleration), accelerating by means of the cruise control can help by allowing your speed to creep up more smoothly than is possible with the accelerator pedal.Multiple driving modes with hybrids: Take full advantage of the multiple modes of the hybrid drive system. When possible get to the electric drive mode where the wheels are being powered by the electric motor with energy stored in the hybrid battery. In that mode, the engine is driving M2 which tries to charge the battery ahead of the full depletion by the forward motion. Light touch on the accelerator when in that equilibrium condition will get in excess of 50 MPG for long periods of time.Decelerate slowly: With a freeway exit ahead and nobody behind you, let go of the accelerator early. If you stay on the gas pedal and then brake hard on the exit ramp, you're depriving your hybrid of the chance to stop burning gas and start generating electric power. Remember that whenever you take your foot off the gas pedal, the electric motor acts as a generator that charges your batteries. If you brake hard, that energy is lost through frictional heat in the brakes.Anticipate traffic-light changes: Look ahead and adjust your speed so you will not have to stop at every light that's now red. Very often, you'll be able to decelerate moderately and remain in motion after the light turns green. When you don't have to go from a standing stop, you save fuel.Respond to the car’s encouragement:The car feeds back information to encourage better gas mileage. Get tuned in so that you can waste less time at the gas station as well as saving money!!
Leave room: Put some room between your car and the vehicle ahead of you. If you follow too closely, you'll have to brake each time that driver brakes; by leaving a little room, you might have to slow down just a bit to keep the interval. Caution, however: Be watchful for the driver who sees the gap you've left and tries to duck into it and perhaps brake suddenly.Take the level route: In some places, you may know a level route to where you're going, rather than climbing over a hill. Hills kill mileage.Cruise control or manual: Generally, using your cruise control will save gas over a long trip. But cruise control works best on flat terrain, so where it's hilly, you might improve your fuel economy by looking ahead and adjusting your speed to the hills and valleys. Traffic permitting, you might accelerate very slightly after cresting a hill in order to gain speed for the next upslope. Then you'll climb farther up the following hill before applying power. You should be able to do this better than the cruise control because you can see ahead and forecast the need for power whereas the machine cannot. A vehicle's fuel-consumption gauge can be helpful in making this work.Check the tires: Properly inflated tires roll better and should save fuel. They'll last longer too.Smooth out the vehicle: Your hybrid is aerodynamically designed to give you the best drag coefficient. Know that driving with the sunroof open or with an unneeded roof rack in place is costing you mileage. So is driving at high speeds with the windows open.Lighten the load: It costs fuel to move the car and everything in it, so it's wise to check frequently to see if there are items in your car that might be left behind. For example, think about carrying only as much bottled water as you'll need on today's trip. And perhaps omit from your weekday commuting the sports equipment or other things used only on weekends. Likewise, the tire chains that you haven't needed since last winter.Start the vehicle last: It's easy to get into habits that tend to consume power and rob mileage needlessly, such as starting the vehicle first and then doing everything else you need to get going -- fastening belts, stowing hand-carried stuff, parking a drink cup, adjusting the mirrors, checking the traffic flow. Get all of that out of the way before starting the car and you'll save fuel.Turn off unneeded accessories: Air conditioning takes power to operate; so do lights, fans, heated seats and audio equipment. It's easy to forget that the air conditioning is on, so many of us leave it on all the time. But this takes power and power drains fuel. Opening a window at low speeds won't have much effect on your vehicle's aerodynamics, and doing so can save gas. Timing your optional travel to cooler times of the day can make air conditioning unnecessary.Rethink the freeway. In some places, there are surface streets that may provide good alternatives to the most crowded portions of freeways. Although traffic on these streets seems to move more slowly, a few days of comparison travel might reveal that you actually beat the stop-and-go travel times of major freeways. And because your hybrid performs well at low speeds, you might save fuel in a couple of ways.Try some of these ideas from hypermilers and you'll probably notice an improvement in fuel mileage. And because you'll be creating less pollution, the environment will thank you too.