Answer to Question #200080 in Electrical Engineering for Fici

Question

A: With the aid of a suitable diagram, describe the generation of electrical energy in a power station

 

B: With the aid of a suitable diagram, describe the transmission and distribution of electricitythrough to the end users

 

C: With the aid of a suitable diagram/sketch briefly describe the types of transformers used.Include double wound, autotransformers and isolating transformers

 

Answer 1

Part A

Plants for producing electricity:

Electric power plants share several components and are a fascinating study in the many forms and variations of energy required to create electricity.

Almost all power plants function by converting water in a boiler unit into superheated steam at extremely high pressures. In fossil fuel plants, the source of heat from combustion processes may differ from the supply of fuels such as coal, oil, or natural gas. Biomass or waste plant components can potentially be utilized as fuel. Solid waste incinerators are also employed as a source of heat in some places. These fuel sources produce variable quantities of air pollution and carbon dioxide ( a gas implicated in global warming problems).

Turbine-Generator: Superheated steam is used to spin the blades of a turbine, which in turn turns a coil of wires within a circular arrangement of magnets in the generator. The whirling coil of wire generates electricity in the magnets.

Cooling Water: Once the steam has passed through the turbine, it must be cooled and condensed back into liquid water to restart the cycle. A neighboring river or lake might provide refreshing water. The water is returned to the body of water at a temperature that is 10-20 degrees higher than the intake water. Another option is to utilize a very tall cooling tower, with the evaporation of water cascading over the tower providing cooling.

Part B

Electricity is generated at power plants and distributed to clients via transmission and distribution power lines. High-voltage transmission lines, such as those suspended between large metal towers transport power across vast distances to fulfill client demand. For long-distance electrical transmission, higher voltage power is more efficient and less expensive. Lower voltage energy is less dangerous to use in homes and businesses. Transformers at substations raise (step-up) or decrease (step down) voltages to accommodate the various phases of the journey from the power plant to distribution lines that transport energy to homes and businesses.

Part C

A double wound transformer is a typical transformer product that performs voltage change, impedance transformation, isolation, and voltage stabilization. Depending on the use, the manufacturing method differs (or different purposes). Each phase of a three-wound transformer has three wounds. When the one wound is connected to alternating current electricity, the other two wounds can create varying electric potentials. The transformer is used for loads that require two distinct voltage levels. Because there are three distinct voltage levels in power plants and substations, three wrapped transformers are frequently utilized in the power system.

Each phase's high, medium, and low voltage wounds are installed in the same core column. To keep the insulation reasonable, the high voltage wound is normally placed in the outer layer, with the medium and low voltage wounds in the inner layer. The majority of the flux is concentrated in the core due to the strong magnetic conductivity of iron materials. As a result, the two sets of coils may achieve a high level of magnetic coupling. Because of its voltage boost and buck functions, the transformer has become one of the most significant components of the contemporary electric power system. Long-distance transmission becomes more cost-effective as transmission voltage rises. 

The main winding AB from which a tapping at C is taken, resulting in CB acting as a secondary winding. The supply voltage is linked across AB, whereas the load is linked across CB. The tapping might be either fixed or variable. When an alternating current voltage V1 is supplied across AB, an alternating flux is created in the core, causing an emf E1 to be induced in the winding AB. The secondary circuit absorbs a portion of the induced emf.

An isolation transformer is a transformer used to transport electrical power from an alternating current (AC) power source to some equipment or device while separating the powered device from the power source, typically for safety concerns.