26 June 2009
A hybrid automobile with both an internal combustion engine and an electric motor.
The people behind the invention:
Victor Wouk - an American engineer Tom Elliott, executive vice president of
American Honda Motor Company
Hiroyuki Yoshino - president and chief executive officer of Honda Motor Company
Fujio Cho - president of Toyota Motor Corporation
Announcing Hybrid Vehicles
At the 2000 North American International Auto Show in Detroit, not only did the Honda Motor Company show off its new Insight model, it also announced expanded use of its new technology. Hiroyuki Yoshino, president and chief executive officer, said that Honda’s integrated motor assist (IMA) system would be expanded to other mass market models.
The system basically fits a small electric motor directly on a one-liter, three-cylinder internal combustion engine. The two share the workload of powering the car, but the gasoline engine does not start up until it is needed.
The electric motor is powered by a nickel-metal hydride (Ni-MH) battery pack, with the IMA system automatically recharging the energy pack during braking. Tom Elliott, Honda’s executive vice-president, said the vehicle was a continuation of the company’s philosophy of making the latest environmental technology accessible to consumers.
The $18,000 Insight was a two-seat sporty car that used many innovations to reduce its weight and improve its performance. Fujio Cho, president of Toyota, also spoke at the Detroit show, where his company showed off its new $20,000 hybrid Prius.
The Toyota Prius relied more on the electric motor and had more energy storage capacity than the Insight, but was a four-door, five-seat model. The Toyota Hybrid System divided the power from its 1.5-liter gasoline engine and directed it to drive the wheels and a generator.
The generator alternately powered the motor and recharged the batteries. The electric motor was coupled with the gasoline engine to power the wheels under normal driving. The gasoline engine supplied average power needs, with the electric motor helping the peaks; at low speeds, it was all electric. A variable transmission seamlessly switched back and forth between the gasoline engine and electric motor or applied both of them.
Variations on an Idea
Automobiles generally use gasoline or diesel engines for driving, electric motors that start the main motors, and a means of recharging the batteries that power starter motors and other devices. In solely electric cars, gasoline engines are eliminated entirely, and the batteries that power the vehicles are recharged from stationary sources. In hybrid cars, the relationship between gasoline engines and electric motors is changed so that electric motors handle some or all of the driving. This is at the expense of an increased number of batteries or other energy-storage devices. Possible in many combinations, “hybrids” couple the low-end torque and regenerative braking potential of electric motors with the range and efficient packaging of gasoline, natural gas, or even hydrogen fuel power plants. The return is greater energy efficiency and reduced pollution. With sufficient energy-storage capacity, an electric motor can actually propel a car from a standing start to a moving speed. In hybrid vehicles, the gasoline engines—which are more energy efficient at higher speeds, then kick in. However, the gasoline engines in these vehicles are smaller, lighter, and more efficient than ordinary gas engines. Designed for average—not peak—driving conditions, they reduce air pollution and considerably improve fuel economy. Batteries in hybrid vehicles are recharged partly by the gas engines and partly by regenerative braking; a third of the energy from slowing the car is turned into electricity. What has finally made hybrids feasible at reasonable cost are the new developments in computer technology, allowing sophisticated controls to coordinate electrical and mechanical power.One way to describe hybrids is to separate them into two types: parallel, in which either of the two power plants can propel the vehicle, and series, in which the auxiliary power plant is used to charge the battery, rather than propel the vehicle. Honda’s Insight is a simplified parallel hybrid that uses a small but efficient gasoline engine. The electric motor assists the engine, providing extra power for acceleration or hill climbing, helps provide regenerative braking, and starts the engine. However, it cannot run the car by itself. Toyota’s Prius is a parallel hybrid whose power train allows some series features. Its engine runs only at an efficient speed and load and is combined with a unique power splitting device. It allows the car to operate like a parallel hybrid, motor alone, engine alone, or both. It can act as a series hybrid with the engine charging the batteries rather than powering the vehicle. It also provides a continually variable transmission using a planetary gear set that allows interaction between the engine, the motor, and the differential which drives the wheels.
In 2001 Honda and Toyota marketed gas-electric hybrids that offered better than 60-mile-per-gallon fuel economy and met California’s stringent standards for “super ultra-low emissions” vehicles. Both companies achieved these standards without the inconvenience of fully electric cars which could go only about a hundred miles on a single battery charge and required such gimmicks as kerosene- powered heaters. As a result, other manufacturers were beginning to follow suit. Ford, for example, promised a hybrid sport utility vehicle (SUV) by 2003. Other automakers, including General Motors and Daimler Chrysler, also have announced development of alternative fuel and low emission vehicles. An example is the ESX3 concept car using a 1.5-liter, direct injection diesel combined with a electric motor and a lithium-ion battery While American automakers were planning to offer some “full hybrids”—cars capable of running on battery power alone at low speeds—they were focusing more enthusiastically on electrically assisted gasoline engines called “mild hybrids.” Full hybrids typically increase gas mileage by up to 60 percent; mild hybrids by only 10 or 20 percent. The “mild hybrid” approach uses regenerative braking with electrical systems of a much lower voltage and storage capacity than for full hybrids, a much cheaper approach. But there still is enough energy available to allow the gasoline engine to turn off automatically when a vehicle stops and turn on instantly when the accelerator is touched. Because the “mild hybrid” approach adds only $1000 to $1500 to a vehicle’s price, it is likely to be used in many models. Full hybrids cost much more, but achieve more benefits.
H. Piper, an American engineer, filed the first patent for a
hybrid gas-electric powered car in 1905, and from then until
1915 they were popular, although not common, because they
could accelerate faster than plain gas-powered cars. Then the
gas-only models became as swift. Their hybrid cousins fells by
Interest in hybrids revived with the unheard-of gasoline
prices during the 1973 oil crisis. The champion of their comeback—
the father of the modern hybrid electric vehicle (HEV)—
was VictorWouk. Born in 1919 in New York City,Wouk earned
a math and physics degree from Columbia University in 1939
and a doctorate in electrical engineering from the California Institute
of Technology in 1942. In 1946 he founded Beta Electric
Corporation, which he led until 1959, when he founded and
was president of another company, Electronic Energy Conversion
Corporation. After 1970, he became an independent consultant,
hoping to build an HEV that people would prefer to
With his partner, Charles Rosen, Wouk gutted the engine
compartment of a Buick Skylark and installed batteries designed
for police cars, a 20-watt direct-current electric motor,
and an RX-2 Mazda rotary engine. Only a test vehicle, it still got
better gas mileage (thirty miles per gallon) than the original
Skylark and met the requirements for emissions control set by
the Clean Air Act of 1970, unlike all American automobiles of
the era. Moreover,Wouk designed an HEV that would get fifty
miles per gallon and pollute one-eighth as much as gas-powered
automobiles. However, the oil crisis ended, gas prices went
down, and consumers and the government lost interest. Wouk
continued to publish, lecture, and design; still, it was not until
the 1990’s that high gas prices and concerns over pollution
made HEV’s attractive yet again.
Wouk holds twelve patents, mostly for speed and braking
controls in electric vehicles but also for air conditioning, high
voltage direct-current power sources, and life extenders for incandescent
Airplane; Diesel locomotive; Hovercraft; Internal combustion
engine; Supersonic passenger plane;