|
Substation
“ Throwing stones in water, look at circles by them formed,
that the given business was not empty expenditure of time ”.
Kozma Prutkov.
Hi inquisitive reader!
If you on this page is means that you interestingly to find out, how
all this works (I have in a kind the railway). I would like to write this article in a
rather popular kind, that the text without shudder could read boy-scout and home help (though I do not know, why it can them interest?). I shall
try to use as small as possible of terms and to lift only most interesting questions.
What for to railway an electricity?
In those near times, when
the steam locomotive was basic steel horse of iron roads, and the trade of fireman
something reminded work of caster in blastfurnace, the
people did not know yet, that will soon. And ahead of them the new machines which have
come on change a pair - diesel engines (locomotives, using in quality of fuel for a
movement diesel fuel, instead of coal or wood, as steam locomotives) waited. The diesel
engines were followed by(with) electric locomotives. Name of the mechanism speaks for
itself - an electric locomotive. It is natural, as fire for life needs fuel (fire wood,
coal etc.), and electric locomotives already there was not enough usual infrastructure,
i.e. the sets of devices and mechanisms for service of a movement - beginning from rails
(or top structure of a way) and, finishing depot (place, where are contained these labour
railway units). That the electric locomotive went, it is necessary somewhere to
take energy for a movement. Variant at once arises, with which the electric locomotive
itself developed the electric power and itself consumed (for example, would have power
station). However it is heavy to present this complex technical structure on wheels, and
the opportunity of realization is very inconvenient. It would be possible to assume the
same realization, as in the underground (i.e. to use contact rails). But try to protect
thousands kilometers of iron roads, that boy has not wanted to transfer a cow through a
way just in this place. And here we smoothly approach to the already fulfilled idea, on
which all iron roads - use of a contact wire work practically care of the electric power
to locomotives.
The simplified circuit of a feed of locomotives (dark blue colour - assembled
electrical circuit).
Do not forget, that the contact wire only
transfers energy, and whence it born is a question of our further consideration. There is
a set of variants circuits connection for an electric locomotive feed with the help
of a contact wire, but for us principle is important, that the electric locomotive only is
the consumer, i.e. it is driven loading. Two kinds of a feed of electric locomotives are
at present applied: on a constant current (3KV) and variable (25КV). Device of an
electric locomotive is in general submitted in figures.
Moving by the machine, you adjust speed of driving by pedals of an accelerator and
coupling. Thus, the necessary quantity of fuel in the engine moves. The similar idea is
incorporated in the mechanism of regulation of a movement of an electric locomotive, -
changing resistance, you change speed of rotation of the engine. It is easiest to consider
these questions on an example of a movement of a liquid.
Comparison of management of the locomotive on an example water mill.
If in the machine all fuel necessary for trip you fill in in a
tank, with work of the locomotive the fuel is on “base” - (substation), whence taking
for a movement through “hoses” - contact wire. Taking into account that the way taking
place by an electric locomotive can be pleased significant (in hundreds kilometers), it
would be very heavy to have it from one “base” - it would be necessary to create a
very strong pressure of a liquid, that it reached on such large distances (i.e. that the
pressure(voltage) in a contact network was so great, that its fall on length of a site of
a movement has no an effect on work of the locomotive).
Cross sections of a contact wire (copper shaped and ova). The top grooves are
used for fastening a wire, and its form allows to improve quality of contact pantograph of
the locomotive.
That it to avoid periodically along a way “bases” i.e.
substation are under construction which give energy the locomotive. So with a having
pressure(voltage) 27,5 KV (alternating current) distance between substations (“bases”)
can reach about 40-60 kms. With a pressure(voltage) 3.3 KV (constant current) distance
between substations about 10-20 kms. I.e. it is possible to make a conclusion, that the
more pressure of water in capacity, the further it can flow, is similar and in a contact
network, the above level of a pressure(voltage), the greater distance between substations
(“ by bases ”). Expenses accordingly there are less, since substations it is necessary
less.
With a constant current 3 KV distance is less (10-20 kms.), than
with variable (40-60 kms.).
Give now we shall look, that by itself
“base”, i.e. substation represents. The substation can be presented as a tank with
fuel, which transfers through “pipelines” (contact network) fuel for locomotives.
Naturally substation too takes “fuel” or electrical energy from more powerful
substation (“ greater power ”) - regional substation.
The comparative circuit substation and
circuit of a feed of the railway.
That is the substation performs the job on
transformation of the electric power for locomotives. Yes, has not forgotten to not tell
nearly - it is not necessary to think, that the substation is applied only to supply of
locomotives. It also is used for a feed of other consumers (beginning from traffic lights
on railway ways and finishing a booth with Pepsi at station). Becouse of this brethren
tracking transformer, which will transform the come pressure(voltage) to a level necessary
for locomotives. From different directions it is surrounded with the correct servants: by
special high-speed switches, which protect the transformer from all troubles and in case
of problems disconnect it. The correct soldiers of substation is a set of the various
relay, frguseyed
watching for a condition “ fields of battle ”, i.e. contact network. And on an output
of substation cost original battle redoubt - feeder cells giving a feed in a contact
network. They too represent small army of the relay, transformers, measuring devices worth
on a battle post. Independently the "collectors of the taxes ” - measuring
transformers and counters of the electric power cost . They watch, how many substation has
spent of the electric power. In modern meters (for example “ ABB Alpha ”,
"Landys&Gir”), except the charge of the electric power it is possible to write
down set of additional parameters, using which it is possible to adjust power consumption.
The meter "ABB Alpha" - powerful
tool for the tax, storage and data processing of electrosupply.
Here the first part
of my story about an electricity by the railway and you, mine grateful and martyred
the reader also was finished, can sleep the sleep of the just. Naturally, it is small page can't contain the immense
information on the railway, but will allow you though in brief to understand, what for
along a railway way someone so frequently has stuck support and something on them has
hung.
If you want to state the negative or positive comments concerning this article, or to
bring in the offers - write!
Sergei Kibitkin, Ternopol distance of electrosupply, Lviv
railroad, Ukraine.
|
|