Hybrid Electric Cars, Combustion Engine driven cars Essay Example for Free

Hybrid Electric Cars, Combustion Engine driven cars Essay AbstractPaper stresses the negative influence of cars on the environment. Hybrid cars technology can diminish the fuel consumption and green house gases production. Different types of electric hybrid powertrains are described Special attention is paid to electric power splitting. Comparison of fuel consumption and CO2 production of one hybrid car and one classic car on European driving cycle is published. 2,5 2 1,5 1 0,5 0 1990 Index Terms Electric hybrid vehicles, European driving cycle, Environment interference, Fuel consumption, CO2 production. Giga tons Milliards of Earth Inhabitants 10Ã'Ž 8 6 4 2 2030 2040 2050 2060 Total world production of CO2 12 2020 2030 The Kyoto protocol summarizes the production of greenhouse gases. The sum is caused not only by cars but in general by men activities on whole Earth. The result from all resources is shown in Fig. 3 which shows the world production of CO2. The Kyoto Protocol tries to estimate if the present and future trends may be sustainable and comes to conclusion that it is a duty of men to accept regulation of this dangerous development. Estimated grows of Planet Earth Population 2010 2020 Fig. 2. Estimated vehicle number on the EarthÃ'Ž Expansion of automobile traffic brought new problems like serious environmental problems with gas emission and fuel consumption. Hothouse gas emission of car combustion engines brought ecological problems namely in big cities. The expected grow of Earth inhabitants will grow as shows Fig. 1. In this paper is SI Unit System used. Milliard means giga (G), 109. 2000 2010 Years I. INTRODUCTION 0 1990 2000 2040 2050 2060 Years Fig. 1. Estimated grows of Planet Earth Population But the expected grow of automobiles will grow much rapidly. The growth will be caused mainly with inevitable living standard improving in many countries like Africa, South Asia and South America together with enlarging of population in these regions. The estimated grows of automobiles over whole Earth is shown in Fig. 2. From comparison of both figures results that the population may grow between years 2000 to 2050 from 6 to 10 milliards that means 1. 7 times, but the expected vehicle number will grow from 0. 7 to 2. 5 milliards that is 3. 6 times. This work was supported by Research Center of Combustion Engines and Automobile Technology. 40 35 30 25 20 15 10 5 0 1980 Rada1 1990 2000 2010 2020 2030 years Fig. 3. Total world production of CO2 These problems are so serious that they became very important theme of international discussions. Results of these discussions were settled in the Kyoto Protocol. Kyoto Protocol is an agreement made under the United Nations Framework Convention on Climate Change (UNFCCC) Automobiles produce approximately a half of the total world production of CO2. Let us imagine that a good new car produces approximately 160 g of CO2 pro each km. There are many possibilities how to diminish this terrible amount. Electric hybrid cars are produced in enlarging numbers and they reach enlarging popularity between customers. They bring a new possibility how to diminish the world CO2 production. II. ELECTRIC HYBRID CAR SYSTEMS Hybrid electric vehicles combine electric and internal combustion engine drive. Hybrid electric vehicles combine the zero pollution benefits of electric motors with the high fuel energy density benefits of the thermal engine. Hybrid electric drives adjust the combustion engine load and revolutions into the point of best motor efficiency and lowest motor emissions. [1], [4], [6], [7]. A. Basic Drive Configurations Series hybrid drive in Fig. 4 presents a combination of different energy sources. In the picture the energy sources are the combustion engine and the battery. The internal combustion engine ICE propels a generator. Total power in form of the generator electric power and the battery electric power are summed in the traction motor. There is no mechanical connection between ICE and wheels. internal combustion engine generator ICE gear box GB battery traction motor TM BAT ICE Fig. 5 Parallel hybrid drive G battery Combined switched hybrid drive in Fig. 6 is based on series hybrid drive with mechanical coupling using a clutch between generator and traction motor. It is series hybrid drive when the clutch is off. BAT traction motor internal combustion engine ICE TM generator G battery BAT coupling Fig. 4. Series hybrid drive Battery acts as energy buffer. Advantage of series hybrid drive is the possibility to operate the thermal engine ICE in optimal revolutions quite free from the car velocity. That results in low specific fuel consumption and in low gas emission for any traction load and car velocity. Efficiency of energy conversions in the system must be taken in account. Parallel hybrid drive in Fig. 5 is a combination of ICE and electric traction motor on the same shaft. Traction motor is supplied by battery and its output is separated from the ICE output. Final traction torque is sum of both motors torque. Power transmission is more effective than in series hybrid drive because the mechanical ICE output is not transformed in electrical output. But the ICE cannot work in optimal load regime because its speed is not free from the car velocity. traction motor internal combustion engine TM Fig. 6. Combined switched hybrid drive The generator supplies the electric energy to the traction motor. When the car speed and ICE speed and power are high but the difference between ICE speed and car speed is small, it is better to operate the scheme as parallel hybrid drive and the clutch is on in such a case. On this regime the ICE power and speed are high and the ICE can operate with small output changes. The difference between desired traction output and ICE optimal output is stored in or discharged from the accumulator. The drive is depicted in Fig. 9. It consists with gasoline engine, double rotor DC generator, and traction motor. traction motor Combined hybrid with planetary gear in Fig. 7 is a topology where mechanical power splitting is used. The splitting is performed in the planetary gear. In this scheme the generator rotates with speed, which is difference between the ICE and car speed. This solution allows splitting the ICE output into two parts. rotating stator control unit generator ~ ~ generator gasoline engine traction motor ICE planet gear Fig. 7. Combined hybrid with planetary grar The first part is proportional to the difference between the ICE and car speed and the second is proportional to the car speed. The first part is transformed into electric energy in the generator and supplied to the traction motor. The second part is transferred by the output planet shaft directly to car wheels. This scheme allows controlling the engine speed and torque and this is the way how to minimize fuel consumption. Electric power splitting drive using DC machines was used on Czechoslovak express motor cars in the year 1936. The patent document was emitted in Czechoslovakia with Nr 53 735 on 25. February 1936. [1], [2], [3]. DC machines were usual on railway vehicles at that time. The vehicle was called :†Slovenska Strela† and remained in service till the year 1950. It should be reconstructed and modernized later on. But electrification of the main railway connection between Prague-Kosice replaced this very interesting vehicle with express electric locomotives. Fig. 8. Express railway car â€Å"Slovenska Strela† clutch rotor output shaft Fig. 9. Electric power splitting drive of express car â€Å"Slovenska Strela† The ICE drives a DC generator which â€Å"stator† and rotor can rotate separately. The â€Å"stator† is firmly coupled with the ICE shaft. The rotor is coupled with car wheels. On the car shaft is mounted a DC electric traction motor supplied by the voltage induced in the generator. The splitting is performed in the generator. The relative speed between generator â€Å"stator† and rotor is difference between the ICE and car speeds. This solution allows split the ICE output into two parts. The first part is proportional to the difference between the ICE and car speed and the second is proportional to the car speed. The first part is transformed into electric energy in the generator and supplied to the traction motor. The second part is transferred directly by means of electromagnetic torque in the generator air gap to the car wheels. This scheme allows controlling the ICE speed independently from the car speed and this is the way how to minimize fuel consumption. Model of Electric Power Splitting Drive Using AC Machines was implemented in the laboratory of JosefÃ'Ž Bozek Research Center of Engine and Automotive Technology at the Technical University in Prague. The physical model of the drive is seen in Fig. 10. It is experimental electric hybrid car drive of a small power. [5], [9], [11], [13], [14], [15]. The output is 7. 5 kW, 0 – 6000 min-1.. Electronic converters and supercapacitor EC are integrated in the circuit between electric power divider SPGM and traction motor TM. The super capacitor as a peak energy storage has 100F, 56V and 400 A. It is able to accept the kinetic energy during braking the vehicle of the mass 1500kg from the velocity 60km/hour and regenerate it during next speeding up. Principle of the system is depicted in Fig. 10. The combustion engine COM ENG drives the electric power divider SGPM. The power divider is a special double rotor synchronous permanent magnet generator. The first rotor is firmly connected with the combustion engine shaft. The second rotor is firmly connected with the traction motor TM and with car wheels. The traction motor is supplied with electric power induced by differential velocity between first and second rotors. Parameters of this electric power (voltage, current and frequency) are changed in electronic converter in EC. Power of the combustion engine is divided into two parts. used for evaluation and comparison of car’s performance, pollution production, efficiencies etc. Simulations were performed on New European Driving Cycle NEDC. The NEDC is shown in Fig. 11. Total distance 10,9km Speed (km/hour) EC ELM CLUTCH COM ENG TM SGPM base Fig. 10. Physical model of Electric Splitting Drive Using AC Machines The incoming power P1=T1* ? 1 is the power of combustion engine producing torque T1 at angular velocity ? 1. Torque T1 is transferred with electromagnetic force to the second rotor, rotating at angular velocity ? 2 which is the same as car velocity. Power transmitted to car wheels by this torque is therefore Pm=T1*? 2. Remaining power is induced by magnetic field into the electric winding arranged on the second rotor. Neglecting losses this power is Pel=P1-Pm=T1*(? 1-? 2). Power Pel is transferred via electronic converter in EC to the traction motor TM and finally added to power Pm on car wheels. Incoming power P1 from combustion engine is by this technique divided into two parts Pm and Pel. Combustion engine can rotate with angular velocity which does not depend from the car velocity III. SIMULATION OF FUEL CONSUMPTION OF HYBRID ELECTRIC CARS Main advantage of electric hybrid cars is the diminishing of fuel consumption. The production of CO2 depends on the fuel consumption and on the working conditions of the ICE. The working conditions of the ICE are much better in electric hybrid cars than in conventional cars generally. Simulations were done with the mathematical model of Electric Power Splitting Drive Using AC Machines. Measured parameters and features obtained in the laboratory [11], [13], [14] were used for the simulation. The mathematical model of a conventional car and hybrid electric car with electric power divider was established in [15] [16]Ã'Ž Comparisons of this art are usualy done on different standard driving cycles. Standard driving cycle represents a driving pattern of a certain geographic region (North America, Europe, Asia-Pacific). These driving cycles are Time (s) Fig. 11 New European Driving Cycle Parameters of compared cars and results of simulation are shown in Tab. 1 TABLE I SIMULATION RESULTS Vehicle type, manufacturer Driving Cycle Total mass (kg) Specific Consumption during total NEDC (l/100km) Total emissions CO2 (g) Specific emissions (g/km) First case Second case NEDC Skoda 1. 2HTP NEDC 1450 1120 5. 1 5. 9 1333Ã'Ž 1540 122. 9 142 Model Fabia Two cases are shown. In both of them the New European Driving Cycle was simulated. Case first: Hybrid electric car with electric power divider. The mass of the car respects the additional mass of electric part of the powertrain. Case second: Conventional car Skoda Fabia 1. 2 HTP. The results shown in Tab. 1 allow to make following conclusions: When comparing fuel consumption and CO2 emissions between hybrid car with electric power divider versus conventional car of the same class (that means the same primary ICE engine power and respecting additional mass of the electric powertrain machines), we can conclude that the fuel consumption and CO2 emissions are significantly lower at the hybrid car. Hybridization of such cars brings not only fuel savings but also is much more environmentally friendly. I. CONCLUSION The production of dangerous greenhouse gas emissions and consumption of world energy resources become a serious problem. Especially CO2 emissions can influence the climate stability of Planet Earth. The automobile business contributes to this development a lot. But the automobile technology has space to be improved. The electric and hybrid electric vehicles can contribute to diminishing of fuel consumption and green gases production. The hybrid electric vehicles makes it possible to operate the combustion engine in more suitable regimes with better fuel combustion conditions. Some hybrid systems even enable to operate the combustion engine in best relation between power and revolutions. Systems with power dividers allow the engine to operate in revolutions that are quite independent from the car velocity. Simulations were done with the mathematical model of Electric Power Splitting Drive Using AC Machines. Measured parameters and features obtained in the laboratory were used for the simulation. Simulations were performed on New European Driving Cycle NEDC. Results of one commercial car and one hybrid electric car with electric power divider are published. Fuel consumption of the hybrid car on the new European Driving Cycle was 5,1 l/km. The commercial car consumed 5,9 l/km. The hybrid car consumption is 13. 6% lower then at commercial car. Similar numbers were obtained with respect to CO2 production. The hybrid car produced 1333 g CO2 on the New European Driving Cycle. Commercial car produced 1540 g CO2. Hybrid car with electric power divider produced 13. 5% less CO2 . REFERENCES [1] V. Klima : Electro-mechanic drive DELKA and its comparison with Dieselelectric drive. (Elektro mechanicky pohon DELKA a jeho srovnani s normalnim Diesel-elektrickym pohonem. ) Elektrotechnicky obzor 1949, Nr. 19, Pg. 489-496 [2] J. Sousedik : Patent document Czechoslovakia Nr 53 735 from 25. February 1936. [3] J. Bilek: Electric drive of motor cars â€Å"Slovenska strela† (Elektricka vyzbroj motorovych vozu â€Å"Slovenska strela†). Elektrotechnicky obzor 1937, Nr16, Pg249-253, Nr. 21 Pg. 331-336. [4] J. Mierlo: Simulation software for comparison and design of electric, hybrid electric and internal combustion vehicles with respect to energy, emission and performances. Vrije Universiteit Brussel. [5] Z. Cerovsky, P. Mindl, S. Fligl, Z. Halamka and P. Hanus: Power Electronics in Automotive Hybrid Drives, 10th International Electronics and Motion Control Conference EPE-PEMC Cavtat- Dubrovnik Croatia, September 2002, ISBN 953-184-047-4 [6] T. Denton : Automobile Electrical and Electronic Systems, SAE International ISBN 0 340 73195 8. [7] Michael H. Wesbrook: The Electric and Hybrid Electric Car, The Institution of Electrical Engineers, 2001, London [9] Lettl, J. , Fligl, S. : Matrix Converter in Hybrid Drives. Proceedings of 8th International Conference â€Å"Problems of Present-day Electrotechnics PPE 2004†, vol. 3, pp. 77-80, Ukraine, Kyiv, June 7-10, 2004, ISSN 0204-3599. [10] Lettl, J. , Fligl, S. : Matrix Converter Control System. Progress In Electromagnetics Research Symposium PIERS 2005 Proceedings, pp. 395-398, China, Hangzhou, August 22-26, 2005, ISBN 1-933077-07-7. [11] Cerovsky Z. , Mindl P. : Super-capacitor in hybrid drive. International Symposium on Electric Machinery in Prague ISEM 2003 , str. 110-111, ISBN 80-01- 02828-3 [12] Zdenek,J. : „Vibrationless Drive Controller Software Designâ€Å". Proc. of XI. int. symp. ISEM2003. Sept. 2003. Prague, pp. 158-165. [13] Cerovsky,Z. Mindl,P. : Hybrid Drive with Supercapacitor Energy Storage, FISITA Conference Barcelona. F193m 2004. [14] Cerovsky Z. , Mindl P. : Efficiency of Hybrid Electric Vehicle Powertrain using Electric Power-Splitting Synchronous Generator with Permanent Magnets. IPEC-Niigata 2005 [15] Mildorf M. : Mathematical model of a drive and fuel consumption of hybrid vehicle. Diploma thesis. 2007, Czech Techn. Uni. Prague. Faculty of El. Eng. [16] Simkova L. : Mathematical model of hybrid car. Bachelor thesis 2004. Czech Techn. Uni. Prague. Phaculty of El. Eng.

Animal Farm, by George Orwell :: Animal Farm Essays

One of the things I like about small presses is that they'll take chances on authors who write about things outside of the mainstream. III Publishing has been one of my favorite sources for libertarian/anarchist fiction and science fiction ever since I picked up and totally enjoyed The Last Days of Christ the Vampire. Now they bring us two fine contributions to anarchist SF literature. If you loved George Orwell's Animal Farm, you'll love this "sequel." Many who have read Orwell's classic missed the basic underlying anti-authoritarian message, instead reading it as an allegory about the Soviet Union. In Anarchist Farm we find an extension of the philosophies underlying Animal Farm, but this time with a more upbeat outcome. Contemporary concerns such as ecocide and animal rights are also woven into this readable book. In fact, it is written in a style appropriate for teenage readers. As in Animal Farm, the main characters here are animals and they talk. They also have cute names. Pancho is a pig who has escaped from the regime that has taken over the farm portrayed in Animal Farm. He is befriended by some wild animals, who are later revealed to be the "Forest Defenders." The Defenders turn out to be very similar to Earth First! Pancho eventually finds a farm whose owner has recently died. In response to the death of their benevolent owner, the animals turn the farm into a successful anarchist collective. As the months roll by, the animal start to worry about what might happen to them when the humans come to auction off the farm. The ending will surprise you. It should also be mentioned that the book also deals with monkeywrenching and its consequences. Anarchist Farm is funny, thought-provoking, and inspiring. It's an excellent sequel to Animal Farm. Let's hope that a few more readers "get it" this time. A.D. is a science fiction story set in the U.S.A. in the near future. Radical changes have altered the very political geography of the continent: the Klux Klan Klan and other white supremacists control what was the southern U.S., the Nation of Islam controls what was the Midwest, and the West Coast is all that remains of the old U.S. "liberal democracy." Fred Hampton Rush Sr. is a middle-aged black man living in Chicago, which is now the capital city of the Lost-Found Nation of Islam in North America.

Environmental Decision Making Applied to Decommissioning Essay

There are three major risks that I worry about on a daily basis in my life. These risks are listed below in order of severity: 1. Depression – Six years ago I was diagnosed with clinical depression. Depression is a progressive and pathological disease that affects the hippocampus and other areas of the brain. There is no single cause of depression. Depression may be caused by a combination of genetic, environmental, or biochemical causes. In my case, I believe my depression is partly hereditary and related to the traumatic childhood event of my father’s premature death. Depression has also been linked with changes to levels of chemicals in the brain such as serotonin and norephinephrine. There are two widely used treatments for depression that have varying degrees of success. Psychotherapy is one treatment that may help some people who suffer from depression. For many people psychotherapy is an ineffective treatment. Anti-depressant drugs are another treatment that is often used in conjunction with psychotherapy. Although there is no scientific evidence that psychotherapy is an effective treatment for depression there is abundant scientific evidence that anti-depressants are an effective treatment for depression, but not necessarily a cure for depression. I currently take three different anti-depressants to control my depression. The risks associated with depression are great. The number one risk is suicide. A person suffering from depression is stricken with feelings of hopelessness and Environmental Decision Making Applied to Decommissioning Page 2 great emotional pain. Suicide is always in the back of a depressed person’s mind as a way to escape the world and depression. It has also been proven that men suffering depression have a 50% more likely chance of dying from cardiac disease than men who are not depressed. This is due to the overflow of stressor hormones that are released in a depressed person’s body. 2. Driving – Driving back and forth to work five days a week is an increasingly risky proposition as the highways become more and more congested with traffic. I have been in one serious accident over the last two years and have been in several near accidents. As more people use their cell phones while driving the risk for all drivers increases. Some states have outlawed the use of cell phones while driving and I believe all states should enact laws like this. Because my commute is fifty miles per day, my perceived sense of risk of having a fatal accident is high. 3. 401(k) Plan – With the economy in a deep recession and the stock markets at ten year lows, my 401(k) plan has suffered huge losses. If the economy and stock markets do not recover in the second half of 2009, then I will have to postpone my early retirement planned for the end of this November. This will definitely have an effect on my depression. Key Risk Without question the key risk for me is depression. As noted above this is a progressive disease and each year that goes by it is getting worse. In order to live a happy and Environmental Decision Making Applied to Decommissioning Page 3 fruitful life this is an unacceptable risk but there is not much I can do about it except continue to take my medications. There is no way to really quantify this risk in terms of numbers. Some factors that influence this risk are my job and my marriage. I have a very stressful job and my marriage is not a happy one. These two factors contribute greatly to my depression. If I can retire early this year, then I will feel much better without the daily grind of a stressful job. Perhaps then I can concentrate on improving my marriage and, thus, reducing my stress and depression further. Environmental Risk Environmental risks associated with driving will be reduced greatly if I can retire early this year. I estimate that without having to come to work each day my yearly mileage will be reduced to 4,000 miles per year from the current 11,000 miles. The risk of having a serious accident will be greatly reduced the less time I spend driving my car. Eliminating the working environment from my life will also reduce the stress in my life and could greatly improve my health by allowing me to spend more time exercising and doing other projects that I would like to do. This will, hopefully, have a profound positive affect on my depression.

What Is the Definition of Unemployment

Conceptually, unemployment is the state of an individual looking for a paying job but not having one. Â  As a result, unemployment does not include individuals such as full-time students, the retired, children, or those not actively looking for a paying job. Â  It also doesnt count individuals who work part-time but would like a full-time job. Â  Mathematically, the unemployment rate is equal to the number of unemployed people divided by the size of the labor force. Â  The Bureau of Labor Statistics publishes this basic unemployment rate (known as U-3) as well as a number of related measures (U-1 through U-6) in order to give a more nuanced view of the unemployment situation in the U.S. Terms related to Unemployment: Frictional UnemploymentCyclical UnemploymentStructrual UnemploymentUnemployment Rate About.Com Resources on Unemployment: Would 0% Unemployment Be a Good Thing?Globalization, Unemployment and Recessions. What is the Link?Why Do We Use the Unemployment Rate? Writing a Term Paper? Here are a few starting points for research on Unemployment:Books on Unemployment:Search Theory and UnemploymentThe Economics of UnemploymentEnvironmental Fiscal Reform and UnemploymentJournal Articles on Unemployment:Equilibrium unemployment as a worker discipline deviceMigration, unemployment and development: a two-sector analysisUnemployment and labor market rigidities