ONE LINE DIAGRAM OF 132 Kv GRID STATION KHANEWAL

The grid station has main 132 kv busbar. The six lines are connected with that

bus bar.

These lines divided with respect to different cities. The first line is called

multan main line. Second line is kabirwala. Third line is khachakhoh. Forth is

chichawatni. Fifth is fauji kabirwala. Six is perowal.

These six lines are used for incoming and outgoing but not use for loads.

The incoming means that power houses and a grid station provided the supply

to 132 kv busbar.

The out going means that 132 kv busbar provided the supply of these lines

with respect to different conditions.

The two lines e.g (kabirwala,perowal and fauji) are permanently connected to

the power houses these lines are use for incoming and out going. If these lines

are used for incoming they provides the supply to 132 kv busbar of grid

station khanewal. Khanewal grid station gets power directly to the power

houses with the help of these lines.

Whenever one of these lines or both lies break the supply than these lines

used for outgoing lines. These lines provided the supply to power houses to

start them. The power house cannot start with out supply. When the power

house start then provided the supply, so these lines will be used for

incoming.

These two lines has same & equal in quantity protection equipments, such as

isolator, circuit breaker, earth isolator and potential transformer.

Multan and Kabirwala

The other two lines e.g multan and kabirwala are connected with the power

houses.these lines are connected with grid stations.

The lines are also used for incoming and outgoing. When used for incoming

then these lines provides the supply to 132 kv busbar from two grid

stations. Whenever one or both grid stations that connected with multan and

kabirwala lines needs the supply from khanewal grid station then these lines

are used for outgoing to maintain the voltage at these grid station.The 132

kv busbar of khanewal gets supply other lines and provides to these lines

these too lines has equal quantity of protection equipment.

The protection equipment are isolator,circuit breaker,circuit breaker and

current transformer.

KHANEWAL AND CHICHAWATNI

Khanewal and chichawatni lines are connected with 132 kv busbar at

Khanewal grid station and other grid station that held near chichawatni and

khachakhoh.

These lines are also use for incoming and outgoing lines. The incoming and

out going procedure is like multan and kabirwala lines. The equipment that

are used for protection of these lines. These lines have equal equipment to

multan and kabirwala.

The substation of Mepco are synchronise with each other. The power houses

are also synchronise with each other. So if load of one of these increases

then the substation gets supply to other substation with respect to

requirement.

66 kv Bus Bar 132 kv bus bar supply the 66 kv bus bar.

That 66 kv line is used for railway load feeder.

The line that connect between 132 kv bus bar and 66 kv bus bar has three isolator,

two CT’s, two circuit breakers, two lightning arrestors, one PT and one

transformer .

The 132kv busbar has only one protection equipment that is PT .

One feeder connected to 66kv bus bar, That feeder has one isolator, CT, one

circuit breaker and one transformer.

All railway loads are connected to that transformer.

11KV FEEDERS There are fifteen feeders used for outgoing supply only. these feeders used for

industries and consumer loads.

There are two lines used to connected the 132 kv busbar and 11kv feeders.

One of these lines has many protection equipments that are e.g isolator, circuit

breaker, CT lightning arrestor and power transformer.

The other line has same equipments and has same feeders connected.

These two lines are connected with 11kv feeders.

These feeders have also circuit breakers and current transformers.

In these feeders the vaccume circuit breaker are used each feeder contain one C.B

and C.T .

These feeders are e.g seed corporation, jafarabad, city no 2 kot mela ram, colony,

wahniwal, city no 1 cold storage, mahrshah, perowal, MES, capacitor, industrial

state.

All protection equipments are used on all lines for different protection methods.

Isolators used on no-load condition, circuit breakers are used for normal

condition, CT and PT are used for purpose of reading of voltage and current with

meter, lightning arresters are used to arrest the lightning.

DC BATTERIES

In khanewal grid station DC batteries are use to give supply for protection

equipments such relays.

The led acid battery used at grid station. Electrolyte for battery is hydro

sulfuric acid (H2SO4).

The led acid battery is made of hoppeck by Germany.

The quantity of batteries used at grid station is 55.

The ampere hour capacity of battery is 480 ampere hour.

The date of all batteries is 25/09/2004.

The float voltages are 119.5V.

CONSTRUCTION

The led acid battery contains two plates and electrolyte.

The plates are made of led per oxide (Pbo2) and use for positive plate and

negative plate is made of led (Pb).

H2SO4 use as electrolyte.

The battery use for large scale. There is a compound used for grid. The

compound contains lead and antimony (Pb & Sb). There is a layer of PbO2 is

also use for surfing on grid. After charging Pbo2 change in acto material.

The plates are divided into negative and positive charges.

The negative plates are large in quantity. Normally one more then positive

plate.

The negative plates should spread around the positive plates to complete the

chemical reaction.

The separators are used between these plates. These separators are any

insulating material.

The separator has two sides. One side consists of grooved used positive to

positive plate for circulating of electrolyte around positive plate.

There is hole on cell upper side to filling and testing of oil. There is a filler

cap on the hole. Filler GP is vent hole used for gas exit.

Battery case and cell covers are made of rabber and acid proof selling

compound are used for outer side sealed.

POSITIVE PLATE: To prepare positive plate grid frame is made of antimony and led. There is surface

of lead per oxide is use o outer side and positive plates becomes.

Its colour is dark brown.

It has two works first is to support actio material and is to pass current to the post.

NEGATIVE PLATE: Its colour is grey.

The difference between positive and negative plates are the actio material is

roughf type.

SEPARATORS: The separators are held between positive and negative plates for to protect the

short circuit. Because separator are insulater material.

The material use for separator are e.g glass wood, micro poric etc.

ELECTROLYTE: The electrolyte is prepare with H2SO4 and water compound.

Both plates are immersed in the electrolyte

To prepare electrolyte we take 5% of water and 1% of H2SO4.during preparation

of electrolyte should be mix one drop step by step into water and a rod should be

used for mixing.

During process gloves, apron and gaggles should be used.

During preparation the temperature of electrolyte increase, so specific gravity

should check with hydrometer.

Normally the specific gravity is 1.205 to 1.215 if specific gravity is less than

correct value than we increase the quantity of H2SO4 should be increased but

higher value of specific gravity the water should be used in electrolyte.

Emergancy lighting used for battery with electrolyte has 1.2 specific gravity

ELEMENT: The assembly of positive and negative plates in any cell is called element cell

CELL COVERS AN D VENT PLUGS: These are made of hard rubber. Two terminal are shown from cell cover. The

vent whole is used for entered the electrolyte the in cell. Vent plugs are made of

rubber.

BATTERY TERMINAL: Battery has two terminals the positive terminal is long and has increase in area

than negative plate.

CELL CONNECTORS: The cell connectors are used to connect the cell in series

CONTAINER: The container has electrolyte and battery plates.

WORKING PRINCIPLE: There are two simple leads strips immersed into H2SO4 electrolyte tank. If these

are connected with respect to the lamp in series with 115 volt dc source. The

current passes through these strips and produces gas bubble. After some time one

plate change its colour and other plate does not change its colour. During that

process the cell charged and volt meter show reading. When the cell discharge its

voltage reduced to 1.75 volt. After this the process of

voltage drop increased and voltage becomes zero. The positive plate colour

changes from dark brown to light brown and at last it colour return to its initial

state.

The positive plate has dark choclate that plate how is componently in spongy. Led

is negative plate maximum bubble exit from negative plate the bubbles are as a

reason of hydrogen gas but some bubbles also come from positive plate due to

oxygen gas the change metalic led into led per oxide. The negative plates can not

changes with chemical reaction. That plate change normally solid led to spongy

led. There is emf produced between these plates and cell will be charged.

CHARGING OF LED ACID BATTERY The discharge battery charge with DC supply. The direction of current should be

positive than during discharging situation. The battery terminals that are positive

and negative should be connected with negative and positive terminals of source.

The first state of battery charging that the lower specific gravity of electrolyte

should be used.

During charging H2 ions moves to cathode and SO4 ions moves to anod. So anod

and cathode becomes to Pb2 and Pb.

The anod becomes to brown and cathode becomes to gray colour.

The specific gravity of H2SO4 increased from 1.18 to 1.27.

The voltage of cell increased from 1.8 to 2.3V.

The cell obsorb energy.

When cell charge it produced gas.

The voltage to charge the battery should be 25% higher the battery voltage.

EARTHING All equipment used at 132 kv grid station all earthed.

Some equipments are placed in open but some protection equipment are

placed in building. Every equipment has separately earthing system.