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When taken together, all of these practices add up to a very responsible effort on the part of lead-acid battery manufacturers and recyclers to keep even small amounts of lead out of the environment. Together, the efforts make a measureable difference.

http://www.batterycouncil.org

THYRISTOR DRIVE CONTROL SYSTEM

Among the various power converters available today, thyristor converters and electric drives have become widely used in various industries, with their capacities ranging from 1 kilowatt to hundreds of megawatts. But as a piece of equipment to be controlled, thyristor converters are fairly challenging, requiring precise execution of different control responses at specific times. Synchronizing such devices with power supplies with alternating current of questionable quality and stability is particularly difficult. Moreover, such equipment necessitates swift alerts to, and appropriate reactions to, emergency situations to protect the converter's power unit from going offline.

The developers of the SU-M1 system elected to address this challenge using a control system based on a powerful, yet relatively inexpensive controller with advanced software. The best controller for the job was Octagon Systems' 6040-series MicroPC, which met the necessary functional requirements, proved capable of controlling the equipment, had a discrete input-output port and digital/analog and analog/digital converters together with ISO 9001-certified reliability. In addition, this controller's processor was compatible with the x86series processors widely used in PCs, giving access to a broad range of software, simplifying the development and deployment of applications.

The SU-M1's developer set out to create a system that would be highly reliable, that would be easy to use, that would provide the necessary data to control the equipment and identify and deal with extraordinary situations through a centralized diagnostics system, and that could work with new and legacy equipment. To meet these goals, the developers used hardware only where it could not be replaced with software, such as the 90-watt power supply, sensors, isolators, RS-422 signal interfaces and pulse shaper for the control of the thyristors. The SU-M1 can also be bundled with a 4x20 LCD display and a KP-2-16 keyboard from Octagon Systems or analog devices. The system can also be connected to a local network through an RS-485/422 port, or to a broader system through a standard radio modem.

The system's software is written in C and is multitasking in strict real-time conditions. The program is compiled for DOS and, after it is converted to protected mode, uses only the file-related functions. The software provides users with a flexible set of controllable parameters for controlling the system such that

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identically configured SU-M1 systems controlling different equipment will differ one from another only in their initial parameter files.

Currently a less expensive version of the system is being developed using the PC/104 modular controllers from Advantech. This version will not be capable of operating in the extreme conditions that the MicroPC allows for, but the software and functionality will be nearly the same.

By Mikhail Blazhenkov, Maxim Sankov and Denis Chentsov,

Mikhail Blazhenkov, Maksim Sankov, Denis Chents

Passenger cars with hybrid gas-electric drive systems have been generating a tremendous amount of publicity lately, due to the technology's fuel savings and reduced emissions. Sales of hybrid passenger vehicles remain strong, with demand still growing. Amid this increasing interest comes a new product from General Motors that will put hybrid technology beneath even more people: hybrid transit buses.

As part of its wide range of fuel-efficient advanced technologies, General Motors has developed a commercial parallel hybrid system that combines a diesel engine with electric motors to power transit buses.

On May 27th, 2004, at Seahawks Stadium in Seattle, GM officially delivered the first of 235 hybrid buses the largest order to date to Metro Transit of King County, Washington. Metro Transit ordered 213 hybrid buses and Sound Transit Regional Express ordered 22 more.

The first buses were put into service on June 5, 2004, with all 235 buses destined for King County expected to be in service by the end of the year.

"This bus employs the most efficient hybrid architecture available in the world today, and is the first step in a larger GM initiative," said Tom Stephens, group vice president of GM Powertrain. "You get low emissions, great fuel economy, smooth and quiet operation, but one other thing is acceleration," explained Stephens.

The hybrid system combines an 8.9-liter Caterpillar diesel engine with two 100 kW electric motors, and can deliver up to 60 percent better fuel economy than a traditional diesel bus. The GM hybrid buses produce much lower hydrocarbon and carbon monoxide emissions than conventional diesel-powered buses. In addition, particulate emissions (tiny pieces of soot and dust) are lowered by 90 percent and nitrogen oxide (NOX) emissions are lowered by up to 50 percent.

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Another advantage of hybrid technology is a regenerative braking system, which captures and stores braking energy. "When you get into a hybrid system like this . . . every time you brake to a stop you convert that braking energy into electricity and store it in the battery, so the next time you accelerate you can use that braking energy to accelerate the bus," explained Stephens.

In addition to the fuel savings and emissions improvements, the GM Hybrid Transit Bus has operational sound levels equivalent to passenger cars. Metro Transit also expects the new buses will result in significant savings in maintenance costs.

Jim Boon, vehicle maintenance manager for Metro Transit Division of King County, told MSN Autos that they have not made any operational compromises nor any changes to the infrastructure to accommodate the new hybrid buses. "This bus just walks on and goes to work," said Boon, who expects to be able to extend oil-change intervals in the hybrid units, saving up to 32,000 quarts of oil per year, plus labor and disposal costs.

In a conventional bus, when you go to drive away you hear the diesel engine rev up and you get the noise and vibration, then you feel a strong jerk when it shifts into second gear.

"This bus is totally different," explained Stephens. "When you go to drive away you hear next to nothing. The electric drive system augments the torque required to drive away and helps the diesel engine so you get a nice, smooth, quiet drive away and there are no shifts whatsoever; it is totally smooth, more like light-rail transportation as opposed to what you conventionally think of with bus transportation."

GM says that the hybrid system being used in the hybrid transit buses today will be scaled and transferred in full-size sport-utility vehicles and full-size pickup truck in the next few years. "These buses are incredibly significant for us," explained King County Executive Ron Sims, "We wanted a 21st century bus with lower operation and maintenance costs that wouldn't be dependent solely on petroleum-based products. We wanted a bus that would literally improve our air quality in a very significant way, and we wanted a bus that is a complete technology."

"The public wants clean air and public transportation is a key component of that," Sims concluded.

http://editorial.autos.msn.com

ENERTIA: THE ELECTRIC MOTORCYCLE

By Paul Seredynski of MSN autos

Green may be the new red, white & blue but when you're talking wheels, how about fun? Or cool? The folks at Brammo Motorsports may be on to something.

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The Ashland, Oregon-based manufacturer the same collection of motorheads responsible for bringing the road-rocket Ariel Atom to U.S. shores have decided to confront the global-warming frenzy with an actual product.

A fun and efficient product. One that makes the similarly two-wheeled and battery-powered Segway look like an environmental pocket protector. It's called the Enertia, an electric motorcycle so slick it couldn't be cooler if it were frozen.

To create the Enertia, Brammo harnessed its enthusiast heart and materialscience expertise to a global sensibility. By approaching carbon emissions from the perspective of true driving enthusiasts, the goal was to provide a practical product that hits on multiple levels: environmentally sound, sharply engineered, cutting-edge materials, fun to own and look at.

The Enertia is a clean-sheet design, conceived from day-one as a twowheeled, zero-emission, fully electric conveyance (it is not a "hybrid"). Its central structure is a carbon fiber monocoque, which serves as both the motorcycle's chassis and its battery tray. Machined 6061-T6 aluminum bits for the bike's threaded hard-points (footpegs, swingarm, etc.), are bonded to the carbon fiber structure a race-bred building technique. Though exceptionally stiff, the entire chassis weighs a mere 16 pounds.

Unlike your typical motorbike, the Enertia flops the engine/fuel-storage ratio. A typical motorcycle is dominated by its centrally mounted engine, and capped with a small gas tank. With the Enertia, the engine is an alternator-sized electric motor mounted at the bottom of the chassis just ahead of the rear wheel. The motor is directly coupled to the rear tire via a chain and sprocket.

Fuel storage for the Enertia consists of six 12-volt lithium-phosphate battery packs. These modules (about half the size of a traditional car battery), are mounted inside the upper and lower channels of the H-shaped carbon fiber chassis three on top, three below. Brammo worked closely with Texas-based Valence Technologies on the application of the lithium-phosphate cells, which unlike lithium-ion or lithium-cobalt, are exceptionally resistant to combusting, even if the batteries are impacted or punctured.

Beneath a small lid where you'd normally fill up a motorcycle with gas is a connection to recharge the bike from any regular 110-volt electrical outlet. The Enertia will reach an 80-percent charge in two hours, and be fully recharged in three. Most cell phones don't even charge that fast.

The 86-pound battery package forms the majority of the Enertia's mass, and at 275 pounds it is extremely light for a street-going motorcycle. It feels even lighter, thanks to an exceptionally narrow profile only 12.5 inches between your knees and a low "moment of inertia." This is the effort required to flick the bike back and forth, which in the case of the Enertia is reduced because the main heft of the bike (the batteries) is concentrated along the bike's centerline.

The power level of the Enertia is user-selectable from 40 to 100 percent. This determines how fast you draw current from (i.e. discharge) the batteries.

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This adjustability allows you to trade more power for decreased range (if you have a shorter commute), or to make the machine more docile for beginners.

The Enertia's power ratings (12 25 horsepower, 17 34 lb-ft of torque) make it comparable to a Kawasaki Ninja 250 in terms of horsepower, but the electric drivetrain provides double the amount of torque (the force that gets you moving), in a package 30 pounds lighter. At the 100-percent power setting, Brammo claims a 0 30 mph time of 3.8 seconds plenty of power for the urban jungle.

A small Enertia logo in the gauge cluster glows red, yellow or green depending on the power draw, to help maximize efficiency. I kept it mostly in the red which had me outpacing traffic and running near the Enertia's 50-mph top speed (easily exceeded on any downgrade) in hopes of gaining a realistic feel for its operating range.

After a completely uneventful, serenely quiet and emission-free 30-mile loop around Portland, (where it truly felt as if I were driving in the future), we returned the bike to Brammo with the gauges still showing 30 percent battery range available.

For those looking to make a lifestyle change, or for a cool "green" machine to get around town on, few options exist that can compete on so many levels. Unless you're rollin' with a crew who can't leave the house without a pocket protector, what says lust for life and love for the big, blue marble better than an electric motorcycle?

http://editorial.autos.msn.com

V2G TECHNOLOGY ON PLUG-IN ELECTRIC CARS

By Larry E. Hall of MSN autos

OK, you're feeling really cool and smart with your purchase of a plug-in hybrid-electric vehicle (PHEV). Your daily round-trip commute to work is barely 30 miles so, recharging the batteries overnight gives you some change back from a ten dollar bill for the weekly cost of electricity. Plus, since you drive entirely on electric juice, there are zero emissions coming out the tailpipe.

Wowzer, what a feeling! But wait, there could be more euphoria in the offing.

What if the local power company was willing maybe even anxious to pay you to draw some of the stored energy from your PHEV's batteries while it was parked during the day? Hey, that would reduce the cost of operating the car even more.

That's exactly what Professor Willett Kempton of the University of Delaware and his colleague Dr. Steven Letendre from the Green Mountain College in Poultney, Vermont, came up with in 1966.

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Called vehicle-to-grid (V2G) technology, the idea is to take advantage of the electrical storage capacity in the vehicle's battery during hot afternoons when demand is highest and most costly to avoid blackouts. During these periods, energy is worth several times more than overnight when vehicles recharge. It is also possible to provide power to a home or businesses on occasions of high electricity demands to avoid high energy prices and help prevent outages.

Kempton and Letendre's idea isn't just a theory presented in a technical journal. In April, California utility Pacific Gas and Electric Company showcased the first-ever utility V2G technology demonstration. The prototype PHEV was a traditional Toyota Prius with an added Lithium-ion battery. PG&E reversed the flow of energy from the vehicle back to an electrical outlet, then ran several lights and appliances to show how V2G could benefit its customers.

The really big potential of using V2G, however, will come from integrating the technology with renewable energy and thereby reducing harmful emissions. During times of maximum demand, electrical utilities have to buy power from expensive and less efficient fossil fuel power generating sources.

PHEVs will charge their batteries at night when energy is inexpensive and is generated with a larger percentage of renewable resources. When demand is high the next day, instead of turning on a fossil-fuel based generator, the utility can purchase the renewable energy stored in the vehicle batteries.

There are numerous hurdles in the path of V2G, not the least of which is the cost of developing and integrating the technology into the automotive and electrical generation industries on a wide scale. But, because V2G has the potential to radically change both the utility of vehicles and the ability of cities to meet peak electrical demand with significantly lower costs while reducing harmful emissions, don't be surprised if the hurdles are overcome sooner than later.

http://editorial.autos.msn.com

FIELD EFFECT TRANSISTOR

In 1945, Shockley had an idea for making a solid state device out of semiconductors. He reasoned that a strong electrical field could cause the flow of electricity within a nearby semiconductor. He tried to build one, then had Walter Brattain try to build it, but it didn't work.

Three years later, Brattain and Bardeen built the first working transistor, the germanium point-contact transistor, which was manufactured as the "A" series. Shockley then designed the junction (sandwich) transistor, which was manufactured for several years afterwards. But in 1960 Bell scientist John Atalla developed a new design based on Shockley's original field-effect theories. By

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the late 1960s, manufacturers converted from junction type integrated circuits to field effect devices. Today, most transistors are field-effect transistors. You are using millions of them now.

MOS-FETs

Most of today's transistors are "MOS-FETs", or Metal Oxide Semiconductor Field Effect Transistors. They were developed mainly by Bell Labs, Fairchild Semiconductor, and hundreds of Silicon Valley, Japanese and other electronics companies.

Field-effect transistors are so named because a weak electrical signal coming in through one electrode creates an electrical field through the rest of the transistor. This field flips from positive to negative when the incoming signal does, and controls a second current traveling through the rest of the transistor. The field modulates the second current to mimic the first one but it can be substantially larger.

How it works

On the bottom of the transistor is a U-shaped section (though it's flatter than a true "U") of N-type semiconductor with an excess of electrons. In the center of the U is a section known as the "base" made of P-type (positively charged) semiconductor with too few electrons. (Actually, the N- and P-types can be reversed and the device will work in exactly the same way, except that holes, not electrons, would cause the current.)

Three electrodes are attached to the top of this semiconductor crystal: one to the middle positive section and one to each arm of the U. By applying a voltage to the electrodes on the U, current will flow through it. The side where the electrons come in is known as the source, and the side where the electrons come out is called the drain.

If nothing else happens, current will flow from one side to the other. Due to the way electrons behave at the junction between N- and P-type semiconductors, however, the current won't flow particularly close to the base. It travels only through a thin channel down the middle of the U.

There's also an electrode attached to the base, a wedge of P-type semiconductor in the middle, separated from the rest of the transistor by a thin layer of metal-oxide such as silicon dioxide (which plays the role of an insulator). This electrode is called the "gate." The weak electrical signal we'd like to amplify is fed through the gate. If the charge coming through the gate is negative, it adds more electrons to the base. Since electrons repel each other, the electrons in the U move as far away from the base as possible. This creates a depletion zone around the base – a whole area where electrons cannot travel. The channel down the middle of the U through which current can flow becomes even thinner. Add enough negative charge to the base and the channel will pinch off completely, stopping all current. It's like stepping on a garden hose to

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stop the flow of water. (Earlier transistors controlled this depletion zone by making use of how electrons move when two semiconductor slabs are put next to each other, creating what is known as a P-N junction. In a MOS-FET, the P-N junction is replaced with metal-oxide, which turned out to be easier to mass produce in microchips.)

Now imagine if the charge coming through the gate is positive. The positive base attracts many electrons – suddenly the area around the base which used to be a no-man's-land opens up. The channel for current through the U becomes larger than it was originally and much more electricity can flow through.

Alternating charge on the base, therefore, changes how much current goes through the U. The incoming current can be used as a faucet to turn current on or off as it moves through the rest of the transistor.

On the other hand, the transistor can be used in a more complex manner as well as an amplifier. Current traveling through the U gets larger or smaller in perfect synch with the charge coming into the base, meaning it has the identical pattern as that original weak signal. And, since the second current is connected to a different voltage supply, it can be made to be larger. The current coming through the U is a perfect replica of the original, only amplified. The transistor is used this way for stereo amplification in speakers and microphones, as well as to boost telephone signals as they travel around the world.

Footnote on Shockley

Shockley watched as Silicon Valley grew but could not seem to enter The Promised Land he had envisioned. He never was able to make field effect transistors, while other companies designed, grew, and prospered. Fred Seitz called Shockley "The Moses of Silicon Valley."

Other transistor types:

Point-Contact Transistor

Junction ("Sandwich") Transistor Resources:

The Way Things Work by David Macaulay

Van Nostrand's Scientific Encyclopedia

The Field Effect Transistor

Interview, Walter Brown, May 3, 1999

http://www.pbs.org

THE HISTORY OF ELECTRIC MEASURING INSTRUMENTS

AND ACTIVE COMPONENTS

Society of Historical Metrology, Japan

Eiju Matsumoto

Abstract:

Precision electric meters are indispensable to the development of technology in this age. The first electric measuring instruments, however, were physically impossible to transport, and were functionally inadequate for use in a laboratory. The measuring instruments of today have evolved into sturdy, easy-to-use instruments with higher performance, adopting new active components which have appeared one after another.

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1. Practical electric measuring instrument: Weston moving-coil DC ammeter: electromagnetic mechanism.

After Volta's battery was invented in 1600, the first utilization of electricity was in telegraphic communication. What kind of measuring instrument was required for telegraphic communication? Probably, neither voltage nor current needed to be measured regularly. Measurement was necessary only at times of failure or in preparation. In other words, a measuring instrument as an electric component was not independently used.

When the electric power industry began to develop in the second half of the 19th century, current and voltage needed to be measured regularly. One of the engineers who put the precision DC ammeter into practical use was Edward Weston (1850-1936). He named the meter the Portable Instrument, as the electric meters until then could be used only in the laboratory, and could not be transported anywhere to make measurements.

Weston aimed at making a highly reliable infallible meter, rather than a sensitive meter, which could be used by anybody, anywhere, with a voltage value read immediately from a scale. He used a permanent magnet for the DC meter, and realized the equal magnetic field in the coil moving portion. A square frame type coil, pivot supports, and two hair springs were then used, making a current pass through the coil. An indicator was attached to the tip of the coil.

In 1886 Weston completed a portable DC ammeter with an accuracy of 0.5%, and subsequently aimed at creating an ammeter for large currents and an AC meter. For that purpose, he invented stable resistance Manganin. In fact, the key component of the meter was a stable permanent magnet and the supporting mechanism of the pivot.

2. The advent of the Fleming Valve and the prototype of AC measurement: Measurement of high-voltage-high frequency.

In 1892, J. A. Fleming (1849 1945), Edison's British adviser, became interested in the "Edison effect." Later, he became an adviser for the Marconi Telegraphy Co., searching for an application of chemical action for a wave detector to replace a coherer. It is said that he started his research because he remembered the "Edison effect," and attempted to carry out supplementary examinations. In contrast to Edison’s method, he put a metal plate, then a cylinder into the electric bulb, naming the equipment an "Oscillation Valve." It was known as the "Valve," a device that lets the flow move in one direction only, because current flows in the cylinder only when a positive voltage is applied. Later, since the shape resembled the electric bulb, it was also known simply as a "Bulb."

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E. Doyle and L. Chubb applied this valve to the measurement of high voltages. This was the first step in adopting the use of an active element in the voltmeter. The valve was filled with mercury or rare gas, and for both the anode plate and the cathode plate, tungsten was used. The meter operated stably as a voltmeter in both cases.

3. De Forest Audion (Audion Vacuum Tube) and BARUBORU (Vacuum Tube Voltmeter): High sensitivity measurement.

Hoping first to improve the characteristics of the valve used in the wave detector, L. De Forest (1873-1961) also put a third electrode in the electric bulb. The electrode was made of a zigzag platinum line, and was put in between the filament and the plate. The effect was more than expected, and it turned out that plate currentcould be controlled by the voltage applied to the grid.

The triode vacuum tube, called Audion, is categorized from present eyes, as a tube containing gas. It was filled with a small amount of gas. Argon and Cesium steam were injected with a low degree of vacuum first. The injection of gas was thought to improve detection sensitivity. However, when high voltage was applied to the tube, a flaw, causing an internal electric discharge, was found. Later, I. Langmuir of GE realized a tube with a long life and high power, using a high vacuum.

The vacuum-tube voltmeter incorporated this tube as an amplifier or a wave detector, being called a Valve-Voltmeter or Vacuum-Tube Voltmeter. In Japan it was uniquely called BARUBORU. The first vacuum-tube voltmeter was invented by E.B. Moullin of the University of Cambridge in 1922, and was put on the market as the product of the Cambridge Scientific Instrument Company. Several kinds of voltmeters were then manufactured, varying from an A-type voltmeter for AC and DC use, the technology of which was most fundamentally on the plate detector, to a B, D-type (AC), a C-type (double range), and a P-type (with a probe).

The scale of the BARUBORU of those days was not linear because the nonlinear nature of the tube appeared as it was.

4. Challenge to Digital: High precision measurement.

The dual slope analog-to-digital conversion circuit, developed in 1957, was an excellent circuit for measuring instruments. This circuit was characterized by dramatically reducing the noise of the commercial frequency existing in the vicinity, and being capable of performing stable digital measurement. Rosewell Gilbert of Weston invented the circuit, but could not put it into practical use in those days, because the A/D converter assembled with tubes was as big as the

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