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The Advantages of AC Power over DC PowerWhich is better,
alternating current or direct current? Back in the 1880s, that
question generated an all-out
current war between two geniuses. On the one side, Thomas Edison
pushed that direct current was saferand would cause less hazard of
electrocution. However, it proved to be cheaper and easier to
transmit the
power of alternating current over long distances. This was the
stance of Edison's competitor, NikolaTesla.
More PowerProbably the biggest advantage of AC over DC is that
you can generate much more power from AC than
DC. Alternating current is generated by large turbines. Direct
current normally comes from batteries or
sometimes from solar panels. Solar panels large enough to power
entire cities would take huge amounts
of land. Batteries use chemical reactions to produce
electricity. Producing a huge battery would be
expensive and impractical. Large turbines can be easily built
and powered using steam, nuclear or
hydraulic power.
Long Distance TransmissionThe ability to generate higher
voltages with AC translates into the ability to transmit that power
overlonger distances. Alternating current is generated at power
stations and transmitted through power lines tosubstations that can
boost AC and keep it going farther distances.
ConversionIn some operations, direct current may be preferred.
However, it is easy to convert AC to DC by usingsimple
transformers. It is much more difficult and costly to convert DC to
AC.
Alternating Current in the HomeOne of the reasons that AC is
better than DC in the home is that AC can be stepped up or down
usingtransformers. On the other hand, when using DC, the power
supply must match the load it powers. If youhave a 120 volt lamp,
then you need a 120 volt battery. If the battery is 240 volts, then
the voltage can be
reduced using a resistor, but, that would waste half the
voltage.
Commercial AdvantagesAnother advantage of the use of alternating
current lies in manufacturing and other production facilitiesthat
drive the economy. Electric motors are used to drive conveyors and
other equipment. The advantagesof the AC motor are that they can
yield a higher output of horsepower than DC motors and they are
simpler in function than a DC motor. Also, transformers allow AC
to be stepped up or down where it is
needed to drive different sized motors.
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What Is the Difference Between AC & DC Electricity?
It includes all basic difference.
The Advantages & Disadvantages of AC and DcAC may be better
for one application, while DC may be better for another. Engineers
need to
Take various aspects of a particular application into account to
decide between the two.
VOLTAGE TransformationA big advantage that AC electricity has
over DC electricity is that it can be easily transformed from a
high voltage level to a low voltage level using a device known
as a transformer. The cables used to
transmit electricity over long distances resist that flow, so
high voltages have to be used to push the
electricity along them. These voltages would be dangerously high
if they came into homes or business
environments, so transformers are used to lower the voltage of
the electricity before it is delivered to the
end user. In the United States, electricity is delivered to end
users at 120 volts.
ReactanceWhen electricity flows down a cable, it generates an
electro-magnetic field. When the current changes, asit does with AC
current, a counter electro-magnetic field is produced that acts as
a resistance to the power
being transmitted. These means that AC transmission of
electricity loses power due to both resistance andto reactance.
Because DC power transmission never changes direction, it is not
susceptible to power loss
as a result of reactance.
