Bheramara Power Plant
Bheramara power plant is one of the oldest power plant in Bangladesh. It is established at 1976 with the capacity of 60MW. It has 3 unit generator. Each generator has the capacity of 20MW. Although the install capacity is 60MW but for a long time use, now the capacity is almost 47MW. At the beginning it was a based plant but now for high cost and low generation this is known as peaking power plant.
How does diesel engine work
We have an opportunity to visit this power plan. The Bheramara power plant is basically a diesel engine power plant. Here HFO is used as fuel. To produce electricity first thing is to rotate the rotor, normally a turbine is use to rotate. To rotate the turbine in Bheramara diesel is used as fuel. Here an alternator is coupling with 900 which change the angle after 3 minutes later. Here the fuel is compressed and with the help of air the turbine rotate at 5100 rpm having frequency of 60 Hz and the generator is rotate at 3000 rpm. To combined them there is a load gear is used.
In Bheramara power plant they can produce 47 MW, although it has a capacity of 60MW. Production decrease because of long use of engine and others equipment which are too old. There are three unite generator each of them can produce almost 16MW(15.66*3=47MW)
Bheramara power plant is a diesel engine power plant. Here diesel is used as fuel. There is 1% diesel and 50% air used in Bheramara power station. Here the purified air compress in the compressor. Than the compress air is mixed with the fuel(1% diesel) which is burn, from this ignition a high pressure gas is produce and that’s make the turbine rotate.
Diesel engine power plant is normally used for small or medium power supplies. To generate electricity diesel engine is used as prime mover. Its also known as four stroke engine. In this type of engine air is compressed in the compression chamber and fuel is injected. It burn and produce a high temperature gases with high pressure. This pressure is used to drive the turbine and rotate the rotor. After this the gases are come out to the atmosphere.
Bheramara power plant uses AC generator.
There are three generator in Bheramara diesel engine power plant. All three of these generator are two pole. Each of them can produce 15.66MW electricity. The generator is coupled with the alternator with a gear. The engine is V shaped with 12 cylinder and produce voltage is 11KV. We see the three phase line here. Through this three phase the generator supply the generate voltage to the bus and then the transformer. Transformer step-up the voltage from 11KV to 11/132KV.
There are three generators in Bheramara. All three of these generators are two pole generators. Each of them can produce 15.66 MW of electricity. The generators are coupled with the alternators with a gear. The engine is V shaped with 12 cylinders. This three phase the generator supply the generated voltage to the bus bar and then to the transformer.
Generated Voltage and supply voltage
Normally the generating voltage is lower, it is step up by the transformer. Here in Bheramara power plant the generation voltage is 11KV. This lower generating voltage is raise to 132KV by the transformer. The three phase line which is goes to the bus bar it then goes to the transformer where it raise 132KV line to the vacuum circuit breaker and then to the isolator. From the isolator it goes to PT to lighting arrester. Finally it goes to the PGCB sub-station.
In Bheramara power station to run the auxiliary system they pick this power from nearby grid. To the power from grid they use 11/0.4KV step down transformer. There is also a generator which supply DC power in emergency like blackout.
In a power station cooling system is very important. Because to run the power station high pressure and a controlled temperature is much noticeable. For this cooling system needed. In Bheramara power station there are two type of cooling system.
- Water cooling system
- Lube oil cooling system
Water cooling system
For water cooling system here use DEMI water. To
purify the water there are use several chemical and maintain the ph of the water. HT water and LT water are used. HtT water is circulate inside the engine in water jacket. Both water keeps the engine and other components temperature in control. So that increasing the temperature can not make any internal fault.
Lube oil cooling system
Lube oil is another cooling system of te Bheramara power station. In this process Lube oil is take through a pair of pump to a filter. Which is later distribute to other branch pipe. Lube oil goes to the bearing,crankshaft and connecting rod. This lube oil will protect the equipment from damage because of friction. There are used purify air for turbine cell cooling.