Загрузил Дурдона Абдугаффарова

дизельные станции

реклама
Diesel power station
Abdugafforova D.O.
Bisengalieva A.
The diesel power plant consist of following components:
1. engine)
2. fuel system
3. Intake system
4. Exhaust system
5. Cooling system
6. Lubrication system
7. Starting and stopping system
8. Governing system
9. Generator of alternator
1.Engine:
 This is the main component of the power plant.
 The function of engine is to develop mechanical power for generator.
 The diesel engines used for diesel power plants may be four stroke or two
stroke engines.
 A two stroke engine is rugged and compact in construction simple in
mechanical design.
 Cheaper in cost, smaller flywheel required and develops more power for same
speed and piston displacement.
 However, a four stroke engine has lower specific fuel consumption and more
effective lubrication, more flexibility, less noisy exhaust, simple and better
cooling, better scavenging and higher efficiency than a two stroke engine.
 Generally two stroke engines are favoured only for diesel electric power
mainly due to high power output, uniform turning moments, compactness
and less capital cost.
 Nowadays, high diesel oil price and hence high operating cost of two stroke
engine is favoured to use four stroke diesel engines for diesel electric power
plants.
 The diesel engines are available in size from 75 KW to 40MW.
 The size and number of engines depends upon plant capacity, purpose for
which plant is being set up and the load characteristics.
2. Fuel system:
It consist of fuel storage tank, daily consumption tank fuel transfer pump,
strainer, fuel filters, and fuel injection pump.
The fuel oil may be supplied at plant site by truck rail road, tank, cars etc.
The function of fuel system are
1. To transfer fuel from storage tank to dail consumption tank,
2. To filter
3. To increase pressure of fuel
4. To measure and control the fuel supply
5. To inject and atomize ( spray in form of small particles) the fuel in the
engine cylinders.
3.Intake system:
It consists of air supply pipe,
filters, and supercharge in case of
supercharge engine.
The function of air intake system
are
1. To clean air,
2. To supply air for supercharging
in case of supercharge engine,
and
3. To reduce the noise of air
intake.
4.Exhaust system:
In consists of piping from engine to a
point where exhaust gases may be
discharged without danger or
annoyance.
A silencer is usually incorporated in this
system to reduce the noise level.
5. Cooling system:
The function of cooling system
is to provide a proper amount
water circulation all around the
engines to remove the part of
heat from engine cylinder
keeping the low temperature at
predefined level.
The cooling system consists of
water jacket, jacket water
pump, surge tank, cooling
tower, raw water pump and
heat exchanger.
6. Lubricating system:
It consists of lubricating oil tank,
pumps, filters and lubricating coil
cooler.
The function of lubricating system is
to provides a proper amount of oil
to minimise friction and wear of the
rubbing parts.
The oil cooler is installed in order to
keep the temperature or lubricating
oil low in order to sustain the
property of lubricating oil.
7.Starting and stopping system:
The starting system is used to rotate the engine initially while starting
until firing starts and unit runs in its own power.
Small diesel engine plants are usually started manually by handles but for
large capacity engine the compressed air system is mostly used for
starting system.
Battery driven motors can also be used for starting the diesel engine.
The engine can be stopped by stopping fuel supply to the injection pump
or stopping the action of injection pump
8. Governing system
The system of government is the relationship of authority, power
and function between two or more state organs and government
on a reciprocal basis.
9. Electric Generator:
The function of generator or alternator is to convert
the mechanical energy (shaft power) of engine into
electric energy.
The generator shaft is coupled with engine shaft.
They are provided with automatic voltage regulators
to allow close voltage regulation and satisfactory
parallel operation
The alternators used in diesel electric power plants are
of rotating fields, salient pole construction, speed
ranging from 214 to 1000 rpm (poles 28 to 6) and
capacities ranging from 25 to 5000 KVA at 0.8 power
factor lagging.
thank you for your attention
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