Re: China's Growing Demand for Oil and Its Impact on U.S. Petroleum Markets

On 12 Apr 2006 12:50:14 -0700, "rst0wxyz@xxxxxxxxx"
<rst0wxyz@xxxxxxxxx> wrote:

Electrical Engineering has 2 options:
option 1: electricity, power, and power transmission
option 2: semiconductors and amplifiers

I took option 2 and got into the computer industry. I'm looking for
someone who took option 1 to tackle this job. Someone who has a lot of
experience with generators epsecially generators in small sizes to
generate a large amount of electrons. Or am I just talking to a blank
wall here? EE majors? where are you?


I am sure if you look at the back issues of the IEEE Spectrum you
will find very authorative and comprehensive articles that will
summarise the state of the art in this area. Save a lot of retracing
the same ground.

From a cursory reading of magazines like Popular Mechanics, Scientific
American, etc. the routes that seem to offer the best solutions
include brushless motors and of course advanced battery technology.
viz.

[[http://en.wikipedia.org/wiki/Brushless_DC_electric_motor
In a BLDC motor, the brush-system/commutator assembly is replaced by
an intelligent electronic controller. The controller performs the same
power-distribution found in a brushed DC-motor, only without using a
commutator/brush system. The controller contains a bank of MOSFET
devices to drive high-current DC power, and a microcontroller to
precisely orchestrate the rapid-changing current-timings. Because the
controller must follow the rotor, the controller needs some means of
determining the rotor's orientation/position (relative to the stator
coils.) Some designs use Hall effect sensors to directly measure the
rotor's position. Others measure the back EMF in the undriven coils to
infer the rotor position, eliminating the need for separate Hall
effect sensors, and therefore are often called "sensorless"
controllers. (The BLDC motor has a trapezoidal backemf, while a
brushless AC motor has a sinousoidal backemf.)

BLDC motors can be constructed in two different physical
configurations: In the 'conventional' configuration, the permanent
magnets are mounted on the spinning armature (rotor.) The stator coils
surround the rotor. In the 'outrunner' configuration, the
radial-relationship between the coils and magnets are reversed; the
stator coils form the center (core) of the motor, while the permanent
magnets spin on an overhanging rotor which surrounds the core. In all
BLDC motors, the stator-coils are stationary.]]

as the "outrunner" configuration can be built right into the wheel
hubs. Battery technology is still the limiting technology and the guy
who invents a superior battery will make zillions and have his name on
the lips of all geeks. Then its a relatively simple matter of having
a gasoline (or hydrogen) motor running at its best operatring speed to
constantly recharge the battery when on the road. As an "on-call
power boost" perhaps the gasoline motor should have an option to
couple directly to the wheels.

You should also read WIRED magazine's article in
http://www.wired.com/wired/archive/12.09/china.html
Pebble bed nuclear power generators have the capacity to generate lots
of clean hydrogen gas as a freebie byproduct. This makes a hydrogen
powered car economy a possibility. I would think this the best way
for China to base its transportation infrastructure future. Only
China has the commercially viable demand to develop and build pebble
bed generators. Its exciting to picture China as the leader in
pebble bed technology and hydrogen car technology too.
.

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