One of the applications of the transformers and the change of voltage and current in electric power plants, ensuring that they meet the largest possible number of end users who use the voltage in different values: industrial, commercial and residential.
Hydroelectric plants use water from reservoirs of large lakes or rivers to move the turbines. Already the thermoelectric plants use fossil fuels or nuclear energy, whose steam turns the turbines. In general, hydroelectric and thermoelectric power plants are away from large consumers of electricity, and this goes to them through transmission lines, stations and substations. HOR04LBHP18
During the course, numerous transformers are used, which not only change the voltage value and control the current, but also maintain stable electrical power and reduce Joule losses.
Another convenience of transformers is that the cables used in the transmission line need not be too thick. Generally, the plant generates voltage in the order of 10 000 V, that the voltage transformer increases to 150 000 to 400 000 V. The acoustic voltage of 400 000 V is not increased to avoid the corona effect that causes loss of energy.
The three-phase induction machines are composed of extremely relevant components, being they, the rotor and the stator and we can say that the rotor is produced from elements such as the axis, whose main objective is to perform the proper transmission of the mechanical power produced by the engine.
The stator features a casing, which sits on a support structure that features a strong cast iron, injected aluminum or finned steel construction, and is capable of withstanding weathering such as corrosion. The stator also has three-phase winding, which is made up of three identical coil assemblies, one of which is designed for each phase, thus forming a three-phase system connected to a three-phase power network.
It has a core of sheets, produced in magnetic steel, that are thermally treated and prepared to reduce the possible losses of iron. It is designed with thermal support so that it can prevent possible problems in its performance, such as warping or fatigue, for example.
In it there is also the plate core, which provides specifications similar to the plates contained in the stator. The rotor also has short-circuit bars and rings, usually designed in die-cast aluminum in one piece.