What is the generation and transmission of electricity
The generation of electrical power is done with the help of natural energy such as wind, water, etc. This natural energy is then converted into electrical energy. In power stations the generation of electricity is done with the help of big generators and they are called as alternators. Primary energy such as wind, water, etc. are used to generate electrical power. A large amount of power is produced by a special plant is known as the generation station or power plant. A generation station has a prime mover coupled to an alternator in order to produce electric power. The mechanical energy of the prime mover will be converted into electrical energy by the alternator. There are many types of power generation station some of them are solar, water and wind power generation. The electrical generation process is done with the help of a generator that consists of a rotor and a stator such as a bicycle dynamo. The generation of electricity will take place when the rotor inside the stator spin by the power of hydro, steam or others.
The electrical power system can be divided into the following regions they are generating stations, transmission systems, Receiving stations, distribution systems, and load points.
- switchyard and substation
- Electrical and electronic symbol
- Transformer working and its types
- single and three-phase transformer
- Transformer faults
- Power transformer
- Transformer testing
- Power quality
What is the difference between electricity distribution and transmission
The transmission of electricity is the transmission of energy from the power station to the substation. While the distribution is the distribution of the electrical power to the consumers.
How electricity is transmitted from power stations to home and what is transmission system in electrical
Transmission of the electricity is from the power station, electrical power will be transmitted from the power stations to substations. The transmission system connects the generating station with the distribution station and the transmission system consists of high voltage lines and bulk power subs. The transmission lines could be AC, DC, underground or overhead lines. Mostly used power transmission is overhead lines. There are two types of transmission systems they are transmission and sub-transmission systems. The electrical power from the power station will be transmitted to the substation with the help of transformers, the transformer will convert the low voltage to high voltage so that it can be transmitted to long distance efficiently. This power will reach the substation and substation has transformers that can convert high voltage power to low voltage power and then it is distributed to the consumers.
How to reduce electrical loss over long-distance transmission
Power transmission for long distances will have power loss, the Joule effect in transformers and power lines causes the major part of power loss. While transmission the energy is lost as heat too in the conductors. These are the losses occurred in the transmission lines, in order to reduce the power loss high voltage power transmission is done.
What are the major electrical transmission line parameters
In an electrical power system, transmission lines play a major role, with the help of transmission lines we would be able to transport the electrical power with small loss from the power sources to the load centers, which would be separated by long distances. The design of the transmission line must be done by considering certain electrical parameters they are series inductance and resistance, shunt capacitance and conductance. The series resistance is depended on the physical composition of the conductor at a given temperature. Because of the presence of the magnetic field and electrical field around the conductors, series and shunt capacitance are produced. Shunt conductance is because of the leakage currents flows across insulators and air.
What are the various system of power transmission
- DC two-wire with midpoint earthed
- DC two-wire
- DC three-wire system
Single-phase AC system
- Single-phase two-wire
- Single-phase three-wire
Three-phase AC system
- Three-phase three wires
- Three-phase four wires
The sending end of the transformer will step up the alternating current to high voltages and it will be converted into direct current with the help of mercury arc rectifier, then the transmission of electrical power is done with the high DC voltage and when it reaches the receiving end it will be converted to alternating current by the thyratrons. After that, the AC will be reduced to low voltage for the distribution.
What are the advantages of DC transmission
- Distribution of the power can be done by the help of two conductors
- There won’t be any inductance and capacitance
- DC transmission lines don’t have any skin effect
- Voltage drop and corona loss is low
What are the disadvantages of DC transmission
High voltage is difficult to produce and the transformers cannot be used to increase and decrease DC voltage.
AC power transmission
The power generation station will generate alternating current and it is transmitted through the transmission lines. The transmission of AC power is done by three-phase three-wire and three-phase four-wire systems. There are two types of transmission of AC power they are primary and secondary transmission.
Primary transmission is the transmission of the AC from the power plant to the substation over the transmission lines with the help of a step-up transformer. So high voltage transmission is done. In the secondary transmission, the high voltage AC power which is transmitted by the primary transmission is reduced by a step-down transformer and then it is transmitted to the substations.
What are the advantages of AC transmission
- High-level voltage can be produced by alternating current
- Voltage can be increased or decreased
- High voltage transmission can be done by using AC power and this will reduce the loss
- Substation maintenance is easy and less expensive
What are the disadvantages of AC transmission
- Capacitive and inductive effect can be seen in AC lines
- Effective conductors are needed because of the skin effect
- The construction of AC transmission is complicated and more copper conductors are required to transmit AC.
Why DC is not used for power transmission
Alternating current is easy to distribute than DC, by using AC we can vary its voltage so for long-distance transmission high voltage is required to reduce the resistive losses in the cable. In the case of DC we won’t be able to vary the voltage like in AC, so DC is not used in transmission purpose.
What are the types of systems which is used for power transmission
Overhead and underground systems are the two types of the transmission system, the overhead transmission is used for the transmission of power for long-distance. Proper spacing between the conductors must be done, so that electrical discharge between the conductors can be prevented. The over-head type of system is easy to repair when compared to the underground system. The underground type system is used for urban substation, in high load density areas. All the conductors will be insulated from each other. Mostly the voltage level used for the underground system is 66KV because of the difficulty to design the appropriate insulation for higher voltage levels. The underground transmission system is more expensive than the overhead because the underground cables must be insulated, installed, in a pipe and cooled with the oil circulation system. The underground transmission system is very difficult to repair.
What are the difference between underground transmission and overhead transmission system and which one is better
We could get uninterrupted continuity of supply, the interruption of the supply due to the weather conditions is not seen in the underground transmission system. In the case of overhead, the weather condition would affect it. Maintenance is less for an underground system, while the overhead maintenance is high when compared to the underground system. Underground cable life is high and the voltage drop is less. The initial cost for the underground system is very high and the distribution of power is only possible at low and medium voltages. The overhead lines can be used for long-distance transmission and the conductor is less expensive, if the transmission voltage is increased the size of the conductor can be decreased and this will helpful for transmission, so overhead lines are mostly preferred.
What is the power distribution network and how does electrical distribution system works
The power from the transmission grid will be stepping down to the distribution grid, in order to do the distribution of power. In a power substation, there will be a transformer to do the step-down process to make the voltage suitable for distribution voltage. Then the distribution power is split into multiple directions with the help of a “bus”. The distribution system provides the power to individual consumer premises, distribution of electrical power is done by distribution networks.
Distribution through a substation
A distribution network consists of the following parts they are feeder, distributor, and service mains. The substation is connected to the area where power is to be distributed is by the help of a feeder, it is a conductor and the current will remain the same because no tapping is taken from the feeder. The distributor is a conductor that would do the connection from a pole-mounted transformer to the customer, the current through a distributor is not constant because tapings are taken at various places. Service mains is a small cable that connects the distributor to the customer’s meter.
The primary and secondary distribution system
In the primary distribution system, voltage is higher than the general utilization, commonly used primary distribution voltage is 11KV – 3.3KV. A primary distribution system is a form of high voltage distribution, mostly the primary distribution is used by factories. Secondary distribution is done for normal consumers and it would be in the range of 440/230 V, 3 phase, 4 wire system.
What are the types of electrical power distribution system
Radial distribution system
In this type of distribution, separate feeders radiate from a single substation and feed the distributors at one end, there will be only one path connection between the substation and the customer. The flow of electricity is in a single path and if it is interrupted then the result will be the complete loss of power.
What are the advantages and disadvantages
The advantages are low cost and simple planning. The disadvantages are, this type of system is only possible when power is generated at low voltage and the substation is located at the center of the load. The distributor nearer to the feeding end will be heavily loaded and at the far end would experience voltage fluctuation.
Ring or loop distribution system
More than one path will be present between the power source and customer, the connection is done in the form of a loop circuit, it starts from the substation and ends in the substation after serving the areas to be served.
What are the advantages and disadvantages of the ring distribution system
The advantages are they are more reliable and less conductive material is needed and the voltage fluctuation is less. It is difficult to design this system.
Interconnected distribution system
In this type of distribution, it is supplied by a number of feeders, radial primary feeders can be tapped off from the interconnecting tie feeders. This type can also serve directly from the substation.
What are the advantages and disadvantages of the interconnected system
The reliability of the supply is high and less loss and quality of service are high. The disadvantages are the initial cost is high, and they are very difficult to design planning and operation.