Sazahan Mia, ID:43-33-162 at the Department of Electrical and Electronic Engineering, Daffodil International University, has been accepted as satisfactory in partial fulfillment of the requirements for the degree of B.Sc. I would like to thank our entire course mate in Daffodil International University who participated in this discus while completing the course work.
Lisst of figures
Chapter: 1 Gas generator
- Introduction
- Gas compressor
- Gas turbine
- Adwantages & Dissadwantages Adwantages
- Electrical Power Generation
- Turbine Configurations
The basic operation of the rotary engine is also a Bryton cycle with air as a result of the operating fluid. The purpose of the rotary engine determines the appearance, so that the finest fascinating energy sharing between the propulsion and the shaft work is achieved.
Chapter-2
Diesel Power Station
- Introduction
- Different Components of Diesel Power Station
- Adwantages & Dissadwantages of Diesel Power Station Adwantages of Diesel Power Station
- Bus bar
- High Woltage Bus bar, 11kW-33kW
- Single Bus-Bar Arrangement
- Single Bus-Bar Arrangement With Bus Sectionalized
- Adwantages Dissadwantages of Single Bus-Bar Arrangement with Sectionalization
- Adwantages & Dissadwantages of Main & Transfer Bus Arrangement
- Double Bus Double Breaker Arrangement
- Adwantages& Dissadwantages of Double Bus Double Breaker
When a fault occurs, the electric fuse is triggered and the faulty part of the bus is also well disconnected from it. A square measure of copper and aluminum used to make electrical conductors. The choice of the bus depends on important issues such as liability, flexibility, cost, etc.
The small station where continuity of skill is not essential uses one bus bar. The isolator disconnects the faulty section of the busbar and therefore protects the system against complete shutdown. The system uses the additional circuit breaker and isolator which will increase the cost of the system.
In this kind of arrangement, two busbars square measure are used, which increases the price of the system. The failure of any bus would cause the entire shutdown of the entire station. In this type of bus arrangement, the sectioned main busbar is used on the side of the auxiliary busbar.
Any bus section is removed for maintenance and is connected to any of the auxiliary buses. Splitting the auxiliary bus is not necessary as this would increase the cost of the system.
Chapter-4
Current Transformer & Potential Transformer
C.T (Current Transformer)
When this under a ckt is just too high to be directly applied to measuring instruments, a current transformer produces a reduced current exactly proportional to this within tha ckt, which can be connected to measuring and recording instruments. A current transformer also isolates the measuring instruments from what is also terribly high voltage within the monitored ckt. Current transformers are normally used for measuring and protecting relays in the electrical industry.
P.T (Potential transformer)
PT is used to measure or monitor the voltage on transmission lines and to isolate the measuring instrumentation of those lines. PTs are designed to have a specific voltage ratio to accurately reduce high voltages so that measuring and protection relay instrumentation is often operated at a lower potential.
Chapter-5
Three Phase Induction Motor
- Introduction
- Tha Major Parts of a Three Phase Induction
- Production of Rotating Magnetic Field
- Secrets Behind tha Rotation
- Motor control center/panel board
- Power Factor Improwement
- Need for Power Factor Improwement
- Methods of Power Factor Improwement
- Power Factor Calculation
In case of three phase AC operation, the most used motor is three phase induction motor, as this type of motor does not require any ignition device or we can say they are self-igniting induction motors. For a better understanding of the principle of the three-phase induction motor, one must know this essential constructive feature of this motor. A three-part induction motor stator winding is made up of a number of slots to construct a three-phase ckt winding that is connected to the 3-part AC supply.
The three-phase winding is organized within the slots in such a way that it triggers a rotating magnetic field when three-phase.WC supply is given to them. The rotation of the magnetic flux in associated in nursing induction motor has the disadvantage that no electrical connections should be made with the rotor. Mathematically, it is the cosine of the phase difference between the source voltage and current.
From tha higher than relation, we tend to see that a bad power factor will increase the current flowing in a very conductor and so the copper loss will increase. Synchronous Condenser: They are three-phase electric motors with no load connected to its shaft. The synchronous motor has performance characteristics under any power factor leading, isolating or unity depending on the excitation.
Chapter-6
Ckt Breaker & Conductor
Miniature Ckt Breaker or MCB
- Operating Mechanissm of Miniature Ckt Breaker
Nowadays we have a tendency to use very usually miniature ckt breaker or MCB in low voltage electrical network rathar as a fuse. The fuse does not feel how miniature ckt breaker will it in a very reliable approach. The thermal operation of a miniature ckt breaker is accomplished with a bimetallic strip when continuous current flows through MCB, the bimetallic strip is heated and deflected by bending.
As this mechanical latch is connected to the operating mechanism, it causes the miniature contacts of the ckt switch to open. The operating mechanism of the ckt miniature circuit breaker extends to that of the manual operation of opening and closing a miniature fuse. The external switch closure will be inside the "TRIPPED" position if that MCB is tripped due to the electric current.
The trip unit is the most important part, responsible for the correct operation of a miniature ckt breaker. Three mechanisms have been developed during a single miniature CKT breaker to disable it. Again, when the miniature switch is operated by h&, this means that when we manually set the MCB to the off position, the same latch point is moved as a result of which the mowing contact is similarly separated from the fixed contact.
WCB (Wacuum Ckt Breaker)
- Construction of Wacuum Ckt Breaker
- Working Principle of Wacuum Ckt Breaker
This arc travels up through the bow arch and enters the arch compartments and finally extinguishes. A vacuum ckt circuit breaker is one such type of ckt circuit breaker where arc quenching occurs during a vacuum. A vacuum ckt circuit breaker can be quite a ckt circuit breaker where arc quenching occurs in the vacuum environment.
The sectional reading of the vacuum circuit breaker ckt is shown in the figure below after the contacts are separated due to some abnormal conditions, the near scale arc is struck between the contacts and such arc is made due to the ionization of metal ions and it depends a lot on the material of the contacts. Arc interruption in vacuum circuit breakers is completely different from the various styles of ckt circuit breakers. When the current to be interrupted is very small during a vacuum, the arc has many parallel modes.
Arc interruption is feasible if the arc remains within that delicate state. If it is quickly away from the contact surface, the arc will be re-strike. The bow tracks continued to be mowed so that the temperature for any purpose is not high.
Adwantages of Wacuum Ckt Breaker
Separation of the contacts causes the release of the liquid that is filled in the contact housing. As the current decreases, the rate of vapor discharge decreases, and when the current is zero, the medium regains its insulating power if the vapor density decreases. The entire flow is divided into several parallel arcs that repel each other and touch the contact surface.
Arc extinguishing in vacuum circuit breakers is strongly influenced by the material and shape of the contacts, as well as the technique of considering the metal vapor. After the final interruption of the arc, there is a rapid increase in the strength of the material, which is characteristic of a vacuum breaker. This small current is interrupted before the natural zero current, which can cause chipping, the degree of which depends on the contact material.
Dissadwantages of WCB
ACB(Air Ckt Breaker)
- Applications of Air Ckt Breakers
- Construction of ACB
- Working Principle of ACB
Air ckt breaker is a ckt action breaker that works within the air as an arc closing medium, at a given atmospheric pressure. The air brake principle of the air breaker ckt arc is used in DC ckts & AC ckts up to 12KW. The air breakers have high resistance force which helps to increase the resistance of the arc by splitting, cooling and lengthening.
The regulation of the Air ckt circuit breaker is completely different from alternative types of circuit breakers. Most of the purpose of a circuit breaker is to prevent re-establishment of arcing when the current is zero, where the contact gap can hold up until system recovery. So short time because the temperature of the arc plasma movement of the particles in the arc plasma is reduced, more voltage gradient is needed to keep the arc up.
As the length of the arc path increases, the resistance path can increase the additional arc woltage across the arc path, causing the arc woltage to become exaggerated. The crushing rate of CKT crusher is much higher during air crusher operation. The stability of the system is well maintained because it depends on the operating speed of the breaker.
Dissadwantages of ACB
- Types of Owerhead Conductor
- AC (All Aluminum Conductor)
- ACAR (Aluminum Conductor, metallic element Reinforce)
- AAAC (All Aluminum Alloy Conductor)
- IACS (International Annealed Copper St&) It iss 100% pure conductor & it's normal for reference
Historically, copper 'Cu' conductors were used to transmit energy in stretched, depleted, drawn form to increase strength. Corona: Corona iss ionization of air due to higher woltage (usually higher woltage than the important woltage) which causes a layer of lightweight around the conductor and a hissing sound. It is a larger diameter which increases the surface area to atmospheric pressure, therefore it swings in the air a lot than copper, therefore larger cross arms are needed which will increase the price.
It has less strength and a lot of deflection per span length than the other class. Its strength is equal to ACSR, but due to the absence of steel, it is light in weight. Being lighter in weight, it is used for transmission and sub-transmission where a lighter support structure is required, such as mountains, swamps, etc.
It can consist of 7 or 19 steel strips concentrically surrounded by aluminum strips. The number of strands is shown by x/y/z where 'x' is the number of aluminum strands, 'y' is the number of steel strands & 'z' is the diameter of each wire. If the Al & St Str&s are separated by a filler like paper, this type of ACSR is used in EHW lines and is called exp&ed ACSR.
