Production, transmission and consumption of electricity. Abstract Production, Transmission and Use of Electric Energy

in physics

on the topic "Production, transmission and use of electricity"

students 11 class A

MOU school number 85

Catherine.

Essay plan.

Introduction

1. Electricity production.

1. Types of power plants.

2. Alternative energy sources.

2. Electricity transmission.

transformers.

3. Use of electricity.

Introduction

The birth of energy occurred several million years ago when people learned how to use fire. The fire gave them warmth and light, was a source of inspiration and optimism, weapons against enemies and wild animals, therapeutic agent, an assistant in agriculture, preservative of products, technological means, etc.

The beautiful myth of Prometheus, who gave people to people, appeared in ancient Greece much later, as in many parts of the world, methods of pretty sophisticated handling of fire, its production and extinguishing, conservation of fire and rational use of fuel were mastered.

Over the years, fire has been maintained by burning plant energy (wood, shrubs, reeds, grass, dry algae, etc.), and then the opportunity was found to use fossil substances to maintain fire: stone coal, oil, slate, peat.

To date, energy remains the main component of a person's life. It makes it possible to create various materials, is one of the main factors in the development of new technologies. Simply put, without mastering various types of energy, a person is not able to fully exist.

Power generation.

Types of power plants.

Thermal power plant (TPP), power plant generating electrical energy as a result of the transformation of thermal energy released during organic fuel combustion. The first TPPs appeared at the end of the 19th century and received predominant distribution. In the mid-70s, the 20th century TPP is the main type of electrical stations.

On thermal power plants, the chemical energy of fuel is converted first into mechanical, and then into electrical. Fuel for such a power station can serve as coal, peat, gas, combustible shale, fuel oil.

Thermal electric stations are divided into condensation (CAC) designed to develop only electrical energy and heat and power center (CHP), excluding electrical thermal energy in the form of hot water and steam. Large COPs of the district value were called state district power plants (GRES).

The simplest concept of the COP, operating on the corner, is presented in the figure. Coal is fed to the fuel bunker 1, and from it - to the crushing unit 2, where turns into dust. Coal dust enters the steam generator firebox (steam boiler) 3 having a system of tubes in which the chemical purified water is circulated, called the nutrient. In the boiler, water heats up, evaporates, and the resulting saturated steam is brought to a temperature of 400-650 ° C and under pressure 3-24 MPa enters steam pipelines into a steam turbine 4. Steam parameters depend on the power of the aggregates.

Thermal condensation power plants have a low efficiency (30-40%), since most of the energy is lost with exhausting filling gases and condenser cooling water. Constructing KES is beneficial in the immediate vicinity of fuel mining. At the same time, electricity consumers can be at a considerable distance from the station.

Heat electrofentral It differs from the condensation station installed on it a special heat process turbine with steam selection. On the CHP, one part of the steam is fully used in a turbine for generating electricity in the generator 5 and then enters the capacitor 6, and the other having a greater temperature and pressure is selected from the intermediate stage of the turbine and is used for heat supply. Condensate pump 7 through deaerator 8 and then the nutritional pump 9 is fed to the steam generator. The number of pair selected depends on the need of enterprises in thermal energy.

The efficiency of the CHP reaches 60-70%. Such stations are usually built near consumers - industrial enterprises or residential arrays. Most often they work on imported fuel.

So much smaller distribution received heat stations with gas turbines (GTES), pARKAZY (PGES) and diesel installations.

In the combustion chamber, GTES burn gas or liquid fuel; The combustion products with a temperature of 750-900 ºС enroll into the gas turbine rotating the electric generator. The efficiency of such TPPs is usually 26-28%, power - up to several hundred MW . GTES is usually used to cover electrical load peaks. CPD PGES can reach 42 - 43%.

The most economical are large thermal steam turbine power plants (abbreviated TPP). Most TPPs of our country are used as a fuel coal dust. For the production of 1 kWh electricity, several hundred grams of coal is spent. In a steam boiler, over 90% of the energies secreted by the fuel are transmitted. In the turbine, the kinetic energy of the jet steam is transmitted by Rotor. The turbine shaft is rigidly connected to the generator shaft.

Modern steam turbines for TPP are very perfect, high-speed, high-economical machines with a large resource of work. Their capacity in general reaches 1 million 200 thousand kW, and this is not the limit. Such machines are always multistage, i.e., there are usually several dozen discs with working blades and the same amount, before each disk, groups of nozzles, through which steam jet flows. Pressure and temperature steam gradually decrease.

From the course of physics, it is known that the efficiency of thermal motors increases with an increase in the initial temperature of the working fluid. Therefore, the steam entering the turbine is adjusted to high parameters: temperatures - almost up to 550 ° C and pressure - up to 25 MPa. The efficiency coefficient of TPP reaches 40%. Most of the energy is lost along with a hot waste steam.

Hydroelectric station (HPP), a complex of structures and equipment, by which the energy of water flow is converted into electrical energy. HPP consists of a serial chain hydraulic structures, providing the necessary concentration of water flow and the creation of pressure and energy equipment that converts the energy moving under pressure into the mechanical energy of rotation, which, in turn, is converted into electrical energy.

The pressure of the HPP is created by the concentration of the river falling on the bodied area, or derivation or dam and derivation together. The main energy equipment of the HPP is located in the HPP building: in the machine room of the power plant - hydraulic units, Auxiliary equipment, automatic control and control devices; In the central administration of the control - the operator-dispatcher or auto operator hydroelectric power station. Rising transformer substation It is placed both inside the building of the HPP and in individual buildings or on open areas. Distribution devices Often are located in the open area. The HPP building can be divided into sections with one or more units and auxiliary equipment separated from adjacent parts of the building. With the HPP building or inside it, a mounting platform is created for the assembly and repair of various equipment and for auxiliary maintenance operations of the HPP.

Installed power (in MW) distinguish HPP powerful (St. 250), middle (up to 25) and small (up to 5). Power HPP depends on the pressure (difference of levels of the upper and lower beef ), Water consumption used in hydro turbines, and the efficiency of the hydraulic unit. For a number of reasons (due to, for example, seasonal changes in the water level in reservoirs, the impermanence of the load of the power system, the repair of hydraulic units or hydraulic structures, etc.) The pressure and water consumption are continuously changing, and, in addition, consumption changes when adjusting the power of the hydropower plant. There are one-time, weekly and daily operating cycles of the HPP operation.

According to the maximum intake, the HPP is divided into high-pressure (more than 60 m) average (from 25 to 60 m) and low-profrans (from 3 to 25 m). On the plain rivers, the pressure rarely exceed 100 m, Under the mountain conditions, you can create pressure to 300 through the dam m. And more, but with the help of derivation - up to 1500 m. The hydropower station for the pressure used is approximate, conditional.

According to the scheme of use of water resources and the concentrations of heads, the HPP is usually divided into rUSLOSY , veidine , derivational with pressure and non-pressure derivation, mixed, hydroaccumulating and tidal .

In the robust and reginted hydroelectric water pressure, the water pressure is created by a dam, a permitting river and raising the water level in the upper beef. At the same time, some flooding of the river valley is inevitable. The channels and the high-speed hydroelectric power plants also build on plain multi-water rivers and on mountain rivers, in narrow compressed valleys. For channels, hydroelectric power plants are characterized by pressure up to 30-40 m.

At higher pressure, it is inappropriate to transmit hydrostatic water pressure on the building of hydrostatic water. In this case, type applies dam HPP, in which the pressure front is overlapped with a dam, and the HPP building is located beyond the dam, adjacent to the lower befe.

Another type of layout veidine HPP corresponds to mountain conditions at relatively small river expenditures.

Use of electricity in various fields of science
And the effect of science on the use of electricity in life

The twentieth century became a century, when science invades all spheres of society's life: economics, politics, culture, education, etc. Naturally, science directly affects the development of energy and the scope of electricity. On the one hand, science contributes to the expansion of the scope of electrical energy and thereby increases its consumption, but on the other hand, in the era, when an unlimited use of non-renewable energy resources is hazardous for future generations, the tasks of developing energy-saving technologies are becoming the urgent tasks of science and introduce them to life.

Consider these questions on specific examples. About 80% of the increase in GDP (internal gross product) of developed countries is achieved by technical innovation, the bulk of which is related to the use of electricity. All new to industry, agriculture and life comes to us thanks to new developments in various branches of science.

Most scientific developments begins with theoretical calculations. But if in the nineteenth century, these calculations were performed using pen and paper, then all theoretical calculations, selection and analysis of scientific data and even a linguistic analysis of literary works are made using computers (electronic computing machines), which operate on electrical energy, most convenient for transmission to distance and use. But if initially the computer was used for scientific calculations, now computers have come to life from science.

Now they are used in all areas of human activity: to record and store information, create archives, preparation and editing texts, performing drawing and graphic work, automation of production and agriculture. Electronization and automation of production are the most important consequences of the "second industrial" or "microelectronic" revolution in the economy of developed countries. The development of comprehensive automation is directly related to microelectronics, a qualitatively new stage of which began after the invention in 1971 of the microprocessor - a microelectronic logical device embedded in various devices for managing their work.

Microprocessors accelerated the growth of robotics. Most of the robots used now apply to the so-called first generation and are used in welding, cutting, pressing, coating, etc. The second generation robots come to replace them are equipped with devices for environmental recognition. And the robots "intellectuals" of the third generation will "see", "feel", "hear". Scientists and engineers among the most priority spheres of robots are called nuclear power, the development of space space, transport, trade, warehousing, medical care, waste recycling, mastering the wealth of the oceanic bottom. The main part of robots operate on electrical energy, but an increase in electricity consumption by robots is compensated by a decrease in energy consumption in many energy-intensive industrial processes by introducing more rational methods and new energy-saving technological processes.

But back to science. All new theoretical developments after calculations on the computer are verified experimentally. And, as a rule, at this stage of the study is carried out with the help of physical measurements, chemical analyzes, etc. Here, the tools of scientific research are diverse - numerous measuring instruments, accelerators, electronic microscopes, magnetorezonance tomographs, etc. The main part of these tools of experimental science is operated on electrical energy.

But science not only uses electricity in its theoretical and experimental areas, scientific ideas are constantly arising in the traditional field of physics related to receipt and transmission of electricity. Scientists, for example, try to create electrical generators without rotating parts. In conventional electric motors, the rotor has to bring a constant current to arise "magnetic force". To the electromagnet, the "running rotor" (the speed of its rotation reaches three thousand revolutions per minute) electric current has to be inserted through conductive coal brushes and rings that rub each other and easily wear out. Physicists had a thought of replacing the rotor of a jet of hot gases, a plasma jet, in which many free electrons and ions. If you skip such a jet between the poles of a strong magnet, then by the law of electromagnetic induction there will be an electric current - because the jet is moving. Electrodes with which the current from a hot jet should be excreted, may be fixed, unlike coal brushes of conventional electrical installations. The new type of electrical machine was called a magnetohydrodynamic generator.

In the middle of the twentieth century, scientists have created an original electrochemical generator, called the fuel cell. Two gas is supplied to the electrode plates of the fuel cell - hydrogen and oxygen. At the platinum electrodes, the gases give electrons into an external electrical chain, become ions and, connecting, turn into water. Electricity and water is obtained from gas fuel. Comfortable, silent and net current source for long-range travel, for example, in space, where both products of the fuel cell are especially needed.

Another original way to produce electricity, which has spread lately is to transform solar energy into an electric "directly" - using photovoltaic installations (solar panels). The appearance of "solar houses", "solar greenhouses", "solar farms" is connected with them. Such solar panels are used in space to provide electricity spacecraft and stations.

Science in the field of communications and communications is very violently developed. Satellite communications is already used not only as a means of international communication, but also in everyday life - satellite antennas are not uncommon and in our city. New means of communication, such as fiber technology, allow you to significantly reduce the loss of electricity during the transmission of signals over long distances.

Not bypassed science and scope. With the development of the HTR, the expansion of the production and non-productive spheres of human activity, management is becoming an increasingly important role in improving their effectiveness. From a kind of art that has recently founded on experience and intuition, management today has turned into science. The science of managing, on the general laws of obtaining, storage, transmission and processing of information is called cybernetics. This term comes from the Greek words "steering", "feeding". It is found in the writings of ancient Greek philosophers. However, his new birth occurred in 1948, after the release of the Book of American scientist Norbert Wiener "Cybernetics".

Before the "cybernetic" revolution, there was only paper informatics, the main means of perception of which remained a human brain, and which did not use electricity. The "cybernetic" revolution gave rise to a fundamentally different - machine computer science corresponding to the giant increased information flows, the source of energy for which the electricity is served. Completely new means of obtaining information, its accumulation, processing and transmission, in the aggregate forming a complex information structure. It includes ACS (automated control systems), information banks of data, automated information bases, computing centers, video terminals, copying and photothellaems, nationwide information systems, satellite and high-speed fiber-optic communication systems - all this unlimited expanded the scope of electricity utilization.

Many scientists believe that in this case it is a new "information" civilization coming to the change of the traditional organization of the industrial type society. Such specialization is characterized by the following important features:

· Wide dissemination of information technology in material and intangible production, in the field of science, education, health care, etc.;

· The presence of a wide network of various data banks, including public use;

· Transformation of information into one of the most important factors of economic, national and personal development;

· Free circulation of information in society.

Such a transition from industrial society to the "information civilization" was possible largely due to the development of energy and ensure the use of energy efficient in transmission and use - electrical energy.

Electricity in production

Modern society cannot be submitted without electrifying industrial activities. Already in the late 80s, more than 1/3 of the entire energy consumption in the world was carried out in the form of electrical energy. By the beginning of the next century, this share may increase to 1/2. Such an increase in electricity consumption is primarily associated with an increase in its consumption in industry. The main part of industrial enterprises operates on electrical energy. High electricity consumption is characteristic of energy-intensive industries such as metallurgy, aluminum and machine-building industry.

In this case, the problem of the effective use of this energy faces. When transmitting electricity over long distances, from the manufacturer to the consumer, the loss of heat along the transmission line is growing proportional to the square, i.e. If the current doubles, the thermal losses increase by 4 times. Therefore, it is desirable that the current in the lines is small. To do this, increase the voltage on the transmission. Electricity is transmitted by lines, where the voltage reaches hundreds of thousands of volts. Near the cities that receive energy from the transmission lines, this voltage using a lowering transformer is adjusted to several thousand volts. In the same city at substations, the voltage decreases to 220 volts.

Our country occupies a large territory, almost 12 time zones. This means that if in some regions, electricity consumption is maximally, then the working day and consumption is already over. For the rational use of electricity generated by power plants, they are combined into the electric power systems of individual areas: European part, Siberia, Urals, the Far East, etc. Such association makes it possible to more efficiently use electricity to coordinate the work of individual power plants. Now various energy systems are combined into a single energy system of Russia.

The next possibility of effective use is the reduction of electricity energy consumption with energy-saving technologies and modern equipment that consumes its minimum amount. Such an example can serve steel-smelting production. If in the 60s the main method of smelting was the Matenovsky method (72% of the entire smelting), then in the 90s this technology of smelting was replaced by more efficient methods: oxygen-converter and electrostalposyl.

LITERATURE:

1. Koltun M. World of Physics: Scientific and Artistic Lit-Ra. - M.: Children. lit., 1984.- 271c.

2. Maksakovsky V.P. Geographic picture of the world. Part 1. General characteristics of the world. - Yaroslavl: Verkh.-Volge. kn. Publishing house, 1995.- 320c.

3. Ellion L., Wilkens U. Physics. - M.: Science, 1967.- 808c.

4. Encyclopedic dictionary of young physics / Sost. V.A. Chuyanov. - M.: Pedagogy, 1984.- 352c.

Nowadays, the level of production and energy consumption is one of the most important indicators of the development of the Company's production forces. The leading role is played by electricity - the most universal and easy-to-use energy form. If the consumption of energy in the world is increased by 2 times in about 25 years, the increase in electricity consumption is 2 times the average for 10 years. This means that more and more processes associated with energy spending is translated into electricity.

Power generation. Electricity is performed on large and small electrical stations mainly with the help of electromechanical induction generators. There are two main types of power plants: thermal and hydroelectric. These power plants differ by engines rotating generator rotors.

On thermal power plants, the source of energy is fuel: coal, gas, oil, fuel oil, combustible shale. Rotors of electrical generators are driven by steam and gas turbines or internal combustion engines. The most economical large thermal steam turbine power plants (abbreviated: TPP). Most TPPs of our country use coal dust as fuel. To work out 1 kW. Thousands of electricity is spent several hundred grams of coal. In a steam boiler, over 90% of the energies secreted by the fuel are transmitted. In the turbine, the kinetic energy of the jet steam is transmitted by Rothor. The turbine shaft is rigidly connected to the generator shaft. Steam turbogenerators are very high-speed: the rotor speed is several thousand per minute.

From the course of 10th grade physics, it is known that the efficiency of thermal motors increases with an increase in the temperature of the heater and, accordingly, the initial temperature of the working fluid (steam, gas). Therefore, the steam entering the turbine is adjusted to high parameters: temperatures - almost up to 550 ° C and pressure - up to 25 MPa. The efficiency coefficient of TPP reaches 40%. Most of the energy is lost along with a hot waste steam.

Thermal power plants are the so-called thermal power plants (CHP) - allow a significant part of the energy of the spent pair to use in industrial enterprises and for household needs (for heating and hot water supply). As a result, the efficiency of CHP reaches 60-70%. Currently, CHP in Russia gives about 40% of all electricity and supply hundreds of cities with electricity and warmth.

On hydroelectric power plants (hydropower plants), the potential energy of water is used to rotate the rotors of the generators. Rotors of electrical generators are driven by hydraulic turbines. The power of such a station depends on the water levels created by the dam (pressure) and the mass of water passing through the turbine in each second (water consumption).

Atomic power plants (NPP) play a significant role in the energy sector. Currently, NPPs in Russia give about 10% of electricity.

Main types of power plants

Thermal power plants are built quickly, cheap, but many harmful emissions in the environment and natural reserves of energy resources are limited.

Hydroelectric power plants are built longer, more expensive; The cost of electricity is minimal, but the flooding of fertile lands and construction is possible only in certain places.

Nuclear power plants are built for long, expensive, but electricity is cheaper than on TPP, the harmful effects on the environment is not significant (with proper operation), but requires the disposal of radioactive waste.

Use of electricity

The main consumer of electricity is the industry, which accounts for about 70% of the electricity produced. A large consumer is also transport. An increasing amount of railway lines is translated into electric traction. Almost all villages and villages receive electricity from power plants for industrial and household needs. Everyone knows about the use of electricity for lighting housing and in household electrical appliances.

Most of the electricity used is now turning into mechanical energy. Almost all mechanisms in industry are driven by electric motors. They are convenient, compact, allow the ability to automate production.

About a third of electricity consumed by industry is used for technological purposes (electric welding, electric heating and melting of metals, electrolysis, etc.).

Modern civilization is unthinkable without widespread use of electricity. Violation of the supply of electricity to a large city and even small villages with an accident paralyzing their life.

Electricity transmission

Electricity consumers are available everywhere. It is produced in relatively few places close to sources of fuel and hydroresours. Electricity cannot be preserved on a large scale. It should be consumed immediately after receiving. Therefore, there is a need for electricity transmission over long distances.

Electricity transmission is associated with noticeable losses, since the electric current heats the power lines wire. In accordance with the law of Joule - Lenza, the energy consumed on the heating of the wire wires is determined by the formula Q \u003d I2RT where R is the line resistance.

With a very long length of the line, the transfer of energy can be economically disadvantageous. Significantly reduce the resistance of the line R is almost very difficult. You have to reduce current strength.

Therefore, in large power plants, you set up the increasing transformers. The transformer increases the voltage in the line at the same time, how many times the current is reduced.

The longer the transmission line, the more profitable to use a higher voltage. So, in the high-voltage line of the transfer Volzhskaya HPP - Moscow and some others use a voltage of 500 square meters. Meanwhile, alternators are adjusted to voltages that do not exceed 16-20 kV. A higher voltage would require the adoption of complex special measures to isolate windings and other parts of generators.

Usually a decrease in voltage and, accordingly, an increase in the current force is carried out in several stages. At each stage, the tension is becoming less and less, and the territory covered by the electrical network is increasingly.

With a very high voltage between the wires, the discharge can begin, leading to energy loss. The permissible amplitude of alternating voltage should be such that with a given cross-sectional area of \u200b\u200bthe energy loss wire due to the discharge were insignificant.

The electrical stations of a number of countries of the country are combined with high-voltage power lines, forming a common electrical network to which consumers are connected. Such an association called the power system makes it possible to smooth out the peak loads of energy consumption in the morning and evening hours. The power system ensures the smoothness of the supply of energy to consumers, regardless of their location. Now almost all the territory of our country is ensured by the electricity of the combined energy systems. There is a single energy system of the European part of the country.

Electricity production in the world today plays a huge role. She is the rod of the state economy of any country. Giant amounts of money are invested annually into the production and use of electricity and scientific research related to this. In everyday life, we are constantly confronted with its action, so modern person must have an idea of \u200b\u200bthe basic processes of its development and consumption.

How to get electricity

Electricity production is carried out from its other types using special devices. For example, from kinetic. To do this, the generator is used - a device that converts mechanical operation into electrical energy.

Other existing ways to obtain it is, for example, transformation of the radiation of the light range with photocells or solar battery. Or electricity production by chemical reaction. Or the use of the potential of radioactive decay or coolant.

It produces it on power plants, which are hydraulic, atomic, thermal, sunny, wind, geothermal, and so on. Basically, they all work according to one scheme - due to the energy of the primary carrier, the mechanical (rotation energy) is generated by a specific device (rotation energy), then transmitted to a special generator, where electrotes are produced.

Main types of power stations

The production and distribution of electricity in most countries is carried out by the construction and operation of thermal power plants - thermal power plants. Their functioning requires a large stock of organic fuel, the production conditions of which from year to year are complicated, and the cost is growing. The coefficient of useful return of fuel in the TPP is not too high (within 40%), and the number of environmentally dirty waste is large.

All these factors reduce the prospects of such a method of developing.

Most economically electricity production by hydropower plants (hydropower plants). The efficiency of them reaches 93%, the cost of 1 kW / h is cheaper than other ways. The natural source of energy of such stations is practically inexhaustible, the number of employees is minimally, they are easy to manage. For the development of this industry, our country is a recognized leader.

Unfortunately, the pace of development is limited to serious costs and long-term construction of hydropower plants associated with their remoteness from large cities and highways, seasonal river regimens and difficult working conditions.

In addition, gigantic reservoirs worsen the environmental situation - flood valuable lands around the reservoirs.

Using atomic energy

Nowadays, production, transmission and use of electricity are produced by nuclear power plants - nuclear power plants. They are arranged almost by the same principle as thermal.

The main plus them is a small amount of fuel required. A kilogram of enriched uranium in its performance is equivalent to 2.5 thousand tons of coal. That is why NPPs are theoretically can be built in any area, regardless of the availability of nearby fuel resources.

Currently, uranium reserves on the planet are much larger than mineral fuel, and the impact of nuclear power plants is minimally subject to trouble-free operation.

A huge and serious deficiency of NPP is the likelihood of a terrible accident with unpredictable consequences, which is why there are very serious security measures for their uninterrupted work. In addition, the production of electricity at the NPP is regulated with difficulty - both for their launch, and for complete stops will take several weeks. And there are practically no technology to dispose of hazardous waste.

What is an electric generator

Electricity production and transmission are carried out due to the electric generator. This is a device for converting any types of energy (thermal, mechanical, chemical) into electrical. The principle of its action is built on the process of electromagnetic induction. The EMF is induced in the conductor, which moves in a magnetic field, crosses its power magnetic lines. Thus, the conductor can serve as a source of electricity.

The basis of any generator is the system of electromagnets forming a magnetic field, and conductors that intersect. Most of all alternating current generators are based on the use of a rotating magnetic field. Its motionless part is called a stator, movable - rotor.

The concept of transformer

The transformer is an electromagnetic static device designed to convert one current system to another (secondary) with the help of electromagnetic induction.

The first transformers in 1876 were proposed by P. N. Apple. In 1885, industrial single-phase appliances were developed by Hungarian scientists. In 1889-1891 The three-phase transformer was invented.

The simplest single-phase transformer consists of a steel core and a pair of windings. They are used for distribution and transmission of electricity, because generators of power plants produce it at a voltage of 6 to 24 kW. Transmitting it beneficial at large values \u200b\u200b(from 110 to 750 kW). For this, the power plants are installed increasing transformers.

How to use electricity

Her lion's share is on the supply of industrial enterprises. Production consumes up to 70% of the electricity produced in the country. This figure varies significantly for individual regions, depending on the climatic conditions and the level of industrial development.

Another cost of expenses is the supply of electric transport. EIC power grids are operating substations of urban, intercity, industrial electric transport using permanent current. For alternating current transport, lower substations are used, which also consume power plants.

Another electricity consumption sector is a communal domestic supply. Consumers here are buildings of residential areas of any settlements. These are homes and apartments, administrative buildings, shops, institutions of education, science, culture, health, catering, etc.

How is electricity transmission

Production, transmission and use of electricity - three whales of the industry. Moreover, convey the resulting power to consumers is the most difficult task.

"Travels" it is mainly by means of LP-air lines of power. Although the cable lines are increasingly beginning to use.

Electricity is produced by powerful aggregates of giant power plants, and its consumers serve relatively small receivers scattered through an extensive territory.

There is a tendency to concentrate power due to the fact that with their increasing the relative costs of the construction of power plants, and, consequently, the cost of the resulting kilowatt-hour is reduced.

Single power complex

A number of factors affect the decision to place a large power plant. This is the form and amount of available resources, the availability of transportation, climatic conditions, the inclusion in a single power system, etc., most often the power plant is built away from large foci of energy consumption. The effectiveness of its transfer to considerable distances affects the successful operation of a single energy complex of a huge territory.

The production and transmission of electricity should occur with a minimum amount of losses, the main cause of which is the heating of the wires, i.e., an increase in the internal energy of the conductor. To preserve the power transmitted over long distances, it is necessary to increase the voltage and reduce the current in the wires.

What is LEP.

Mathematical calculations show that the losses in the wires on the heating are inversely proportional to the voltage square. That is why electricity over long distances are transmitted using high-voltage power lines with LEP - high-voltage power lines. Between their wires, the tension is calculated with tens, and sometimes hundreds of thousands of volts.

Power plants located near each other are combined into a single power system precisely using LEP. Electricity production in Russia and its transfer is carried out by a centralized energy network, which includes a huge number of power plants. Unified management of the system guarantees the constant submission to consumers of electricity.

A bit of history

How was the unified electrical network in our country formed? Let's try to look into the past.

Until 1917, electricity generation in Russia was conducted by an insufficient pace. The country lags behind developed neighbors, which has adversely affected the economy and defense capability.

After the October Revolution, the project of electrification of Russia was developed by the State Commission for Electrification of Russia (Abbreviated Goello), headed by G. M. Krzhizhanovsky. More than 200 scientists and engineers were collaborated with her. The control was carried out personally V. I. Lenin.

In 1920, the "Electrification Plan of the RSFSR" was ready for 10-15 years. He included the restoration of the former power system and the construction of 30 new power plants equipped with modern turbines and boilers. The main idea of \u200b\u200bthe plan is to use giant domestic hydroenergoresours. Electrification and the root reconstruction of the entire national economy were assumed. The emphasis was made on the growth and development of the heavy industry of the country.

Famous Plan Goerlo

Since 1947, the USSR became the first in Europe and the world's second electricity producer in the world. It is thanks to the Goello plan was formed as soon as possible the entire domestic economy. The production and consumption of electricity in the country has reached a qualitatively new level.

The implementation of the planned became possible due to the combination of several important factors at once: a high level of scientific personnel of the country, which preserved from the pre-revolutionary times of the material potential of Russia, the centralization of political and economic power, to believe the property of the Russian people and embody the proclaimed ideas.

The plan has proved the effectiveness of the Soviet system of centralized power and government.

Results of the Plan

In 1935, the adopted program was fulfilled and exceeded. 40 power plants were built instead of planned 30, power was introduced almost three times more than it was envisaged according to plan. 13 electric centers with a capacity of 100 thousand kW each. The total capacity of Russian hydroelectric power plants amounted to about 700,000 kW.

During these years, the largest objects of strategic importance were erected, such as the world-famous Dnieper HPP. Under the summary indicators, the Unified Soviet Energy System has surpassed similar systems of the most developed countries of the new and old light. Electricity production by Europe in those years has significantly lagging behind the indicators of the USSR.

Development of the village

If the revolution in the villages of Russia electricity practically did not exist (small power plants installed by large landowners do not count), then with the implementation of the GOELRO plan through the use of electricity, agriculture received a new impetus to development. Electric motors appeared on the mills, sawmills, grain-cleaning machines, which contributed to the modernization of the industry.

In addition, electricity is firmly included in the life of citizens and the village, literally pulling out the "Dark Russia" from the gloom.

in physics

on the topic "Production, transmission and use of electricity"

students 11 class A

MOU school number 85

Catherine.

Essay plan.

Introduction

1. Electricity production.

1. Types of power plants.

2. Alternative energy sources.

2. Electricity transmission.

transformers.

3. Use of electricity.

Introduction

Power generation.

Types of power plants.

The efficiency of the CHP reaches 60-70%. Such stations are usually built near consumers - industrial enterprises or residential arrays. Most often they work on imported fuel.

So much smaller distribution received heat stations with gas turbines (GTES), pARKAZY (PGES) and diesel installations.

Another type of layout veidine HPP corresponds to mountain conditions at relatively small river expenditures.

IN derivational HPP concentration of the river drop is created by derivation; The water at the beginning of the river site used is given from the riverbed with a waterwater, with a slope, significantly less than the average river bias on this site and with the hide of the bends and turns. The end of the derivation is summarized to the location of the HPP building. The waste water is either returns to the river, or is summarized to the next derivational hydropower station. Derivation is beneficial when the river bonus is great.

Special place among HPP hydroaccumulating power plants (GAES) and tidal power plants (PES). The HPP facility is due to the growth of peak power in large energy systems, which determines the generator power required to cover peak loads. The power supply capacity is based on the fact that the electrical energy is free in the power system in a certain period of time, electrical energy is used by GESOP aggregates, which, working in pump mode, injected water from the reservoir to the upper accumulatory pool. During the period of load peaks, the battery energy returns to the power system (water from the upper pool enters the pressure pipe and rotates the hydraulic units operating in the current generator mode).

PES convert the energy of sea tides into electric. Electricity of tidal hydroelectric power plants due to certain features associated with the periodical character of tides and sings can be used in power systems only in conjunction with the energy of regulating power plants that replenish the dips of the power of tidal power plants during the day or months.

The most important feature of hydropower resources compared with fuel and energy resources is their continuous renewability. The lack of fuel need for HPP determines the low cost of electricity produced on hydroelectric power plants. Therefore, the construction of hydropower plants, despite significant, specific investment on 1 kw Installed capacity and long construction deadlines, attached and attached great importance, especially when it is associated with the placement of electric power plants.

Nuclear power plant (NPP), a power plant in which the atomic (nuclear) energy is converted into electrical. The energy generator at NPP is an atomic reactor. The heat that is released in the reactor as a result of a chain reaction of the nuclei of some heavy elements, then the same way as on conventional thermal power plants (TPP) is converted into electricity. Unlike TPP, working on organic fuel, NPP works on nuclear stuel (based on 233 U, 235 U, 239 PU). It has been established that the world's energetic resources of nuclear fuel (uranium, plutonium, etc.) significantly exceed the energy resources of natural reserves of organic, fuel (oil, coal, natural gas, etc.). This opens up extensive prospects to meet the rapidly growing fuel needs. In addition, it is necessary to take into account the increasing amount of consumption of coal and oil for the technological purposes of the global chemical industry, which becomes a serious competitor of thermal power plants. Despite the opening of new fields of organic fuel and improving the methods of its production, there is a tendency to relative, increasing its value in the world. This creates the most difficult conditions for countries having limited fuel reserves of organic origin. Obviously the need for the fastest development of nuclear energy, which already occupies a noticeable place in the energy balance of a number of industrial countries of the world.

The schematic diagram of nuclear power plants with a nuclear reactor having water cooling is shown in Fig. 2. Heat allocated in active zone reactor coolant It is absorbed by water of the 1st contour, which is pumped through the reactor with a circulation pump. Draw water from the reactor enters the heat exchanger (steam generator) 3, where it transmits the heat obtained in the water reactor of the 2nd contour. The water of the 2nd contour evaporates in the steam generator, and a couple is formed, which then enters the turbine 4.

Most often, 4 types of thermal neutron reactors are used at nuclear power plants:

1) water-water with conventional water as a retarder and coolant;

2) graphite-water with water heat carrier and graphite retarder;

3) heavy water with water heat carrier and severe water as a retarder;

4) graffito gas with gas heat carrier and graphite retarder.

The choice of a predominantly used type of the reactor is determined mainly by the accumulated experiments in the reactor, as well as the presence of the necessary industrial equipment, raw materials, etc.

To the reactor and serving systems include: the actual reactor with biological protection , Heat exchangers, pumps or gas plants carrying out the circulation of the coolant, pipelines and fittings circuit circulation, devices for rebooting the nuclear fuel, system of special ventilation, emergency discharge, etc.

To prevent NPP staff from radiation exposure, the reactor surrounds biological protection, the main material for which concrete, water, serpentine sand serves. The equipment of the reactor circuit should be completely sealed. The system of control of places of possible leakage of the coolant is envisaged, measures are taken to ensure that the appearance of non-density and discontinuities does not lead to radioactive emissions and pollution of nuclear power plants and the surrounding area. Radioactive air and a small amount of coolant vapor, due to the presence of leakage from the contour, are removed from the maintenance-free nuclear power plants with a special ventilation system, in which cleaning filters and amusements of excerpts are provided to eliminate the possibility of air pollution. For the implementation of radiation safety rules, the NPP staff monitors the service of dosimetry control.

The presence of biological protection, special ventilation systems and emergency discharge and dosimetry control service allows you to completely secure the maintenance of nuclear power plants from the harmful effects of radioactive exposure.

NPPs, which are the most modern type of power plants, have a number of significant advantages over other types of power plants: under normal functioning conditions, they absolutely do not contaminate the environment, do not require binding to source of raw materials and, accordingly, can be placed almost everywhere. New power units have the power almost equal power of the average hydropower plant, however, the use of installed capacity at nuclear power plants (80%) significantly exceeds this indicator in HPP or TPP.

Significant NPP deficiencies under normal functioning conditions practically do not have. However, it is impossible not to notice the danger of nuclear power plants with possible force majeure circumstances: earthquakes, hurricanes, etc. - Here, the old models of power units represent the potential risk of radiation infection of the territories due to uncontrolled reactor overheating.

Alternative energy sources.

Energy of sun.

Recently, interest in the problem of using solar energy has increased dramatically, because the potential energy capabilities based on the use of direct solar radiation are extremely large.

The simplest solar radiation collector is a stressed metal (usually aluminum) sheet, inside of which pipes with liquid circulating in it are located. Heated due to solar energy absorbed by the collector, the liquid comes to direct use.

Solar energy refers to the most material consumption of energy production. The large-scale use of solar energy entails a giant increase in the need for materials, and, consequently, in labor resources for mining raw materials, enrichment, obtaining materials, manufacture of heliostats, collectors, other equipment, their transportation.

While the electrical energy born by the solar rays is much more expensive than the traditional methods obtained by traditional ways. Scientists hope that the experiments they will spend on experienced installations and stations will help solve not only technical, but also economic problems.

Wind energy.

The energy of moving air masses is huge. The wind energy reserves are more than a hundred times higher than the hydropower reserves of all rivers of the planet. Constantly and everywhere in the earth are blowing winds. Climatic conditions allow you to develop wind power in a huge territory.

But nowadays, engines using wind cover only one thousandth of world energy needs. Because the creation of the designs of the wind vehicles of any wind power plant is attracted by specialists-aircraft manufacturers who know how to choose the most appropriate profile of the blade, explore it in the aerodynamic tube. The efforts of scientists and engineers have created a wide variety of constructions of modern wind plants.

Energy Earth.

People have long been known about the spontaneous manifestations of the giant energy tagged in the bowels of the globe. The memory of mankind keeps legends about the catastrophic eruptions of volcanoes, which claimed millions of human lives unrecognizable the appeal of many places on Earth. The power of the eruption of even a relatively small colossal volcano, it repeatedly exceeds the capacity of the largest energy plants created by the hands of a person. True, it is not necessary to speak about the direct use of the energy of volcanic eruptions, there is no opportunity for people to curb this reciprocal element.

Earth energy is suitable not only for the heating of premises, as is happening in Iceland, but also for generating electricity. Power plants using hot underground sources have been operating. The first such power station is completely low, it was built in 1904 in a small Italian town of Larderllo. Gradually, the power of the power plant grew, all new aggregates entered into operation, new sources of hot water were used, and today the power of the station has already reached an impressive value of 360 thousand kilowatt.

Electricity transmission.

Transformers.

You purchased the refrigerator ZIL. The seller warned you that the refrigerator is designed for voltage in the network 220 V. And in your home network voltage 127 V. Standing position? Not at all. You just have to make extra cost and purchase a transformer.

Transformer - A very simple device that allows you to raise and lower the voltage. AC conversion is carried out using transformers. For the first time, transformers were used in 1878 by the Russian scientist P. N. Yablochkov for powering invented "electric candles" - new at the time of the light source. The idea of \u200b\u200bP. N. Yablochkova was developed by an employee of Moscow University I. F. Usagin, constructed improved transformers.

The transformer consists of a closed iron core, which is used two (sometimes more) coils with wire windings (Fig. 1). One of the windings, called the primary, connects to the source of alternating voltage. The second winding to which the "load" is attached, i.e., devices and devices that consume electricity are called secondary.

The transformer effect is based on the phenomenon of electromagnetic induction. When the AC passed on the primary winding in the iron core, an alternating magnetic flux appears, which excites induction EMF in each winding. And the instantaneous value of the EMF induction e. in Any twist of the primary or secondary winding according to the Faraday law is determined by the formula:

e \u003d - Δ F / Δ t.

If a F. \u003d F 0 co sωt, then

e \u003d Ω F 0 sin. ω t. , or

E \u003d. E. 0 sin. ω t. ,

where E. 0 \u003d Ω F 0 - AMS amplitude in one turn.

In the primary winding having p 1. turns full of emf induction e. 1 equal p 1 e.

In the secondary winding complete EMF. e 2. equal p 2 e, Where p 2. - The number of turns of this winding.

Hence it follows that

e. 1 E 2 \u003d n 1 p 2 . (1)

Voltage amount u. 1 , applied to the primary winding, and EMF e. 1 should be equal to the voltage drop in the primary winding:

u. 1 + e. 1 = i. 1 R. 1 , Where R. 1 - active winding resistance, and i. 1 - Current strength in it. This equation directly follows from the general equation. Usually active winding resistance of little and member i. 1 R. 1 You can neglected. therefore

u. 1 ≈ -e. 1 . (2)

With an open secondary winding of the transformer, the current does not flow in it, and the ratio takes place:

u. 2 ≈ - e. 2 . (3)

Since instant values \u200b\u200bof EDC e. 1 and e. 2 Changes simphase, their ratio in formula (1) can be replaced by the ratio of active values E. 1 and E. 2 these emfs or, given the equality (2) and (3), the ratio of the current voltage values \u200b\u200bu 1 and U. 2 .

U. 1 / U. 2 = E. 1 / E. 2 = n. 1 / n. 2 = k. . (4)

Value k. called a transformation coefficient. If k. \u003e 1, the transformer is downward, with k. <1 - Raising.

When the secondary winding circuit is closed in it flows current. Then the ratio u. 2 ≈ - e. 2 no longer performed accurately, and accordingly the relationship between u 1 and U. 2 It becomes more complicated than in equation (4).

According to the law of energy conservation, the power in the primary chain should be equal to the power in the secondary chain:

U. 1 I. 1 = U. 2 I. 2, (5)

where I. 1 and I. 2 - The active values \u200b\u200bof force in the primary and secondary windings.

Hence it follows that

U. 1 / U. 2 = I. 1 / I. 2 . (6)

This means that, increasing the voltage with a transformer several times, we reduce the current strength at the same time (and vice versa).

Due to the inevitable energy loss on the release of heat in the windings and the iron core of equation (5) and (6) are performed approximately. However, in modern powerful transformers, total losses do not exceed 2-3%.

In everyday practice often have to deal with transformers. In addition to those transformers that we use the Will-Neils due to the fact that industrial devices are designed for one voltage, and another is used in the urban network - except for them have to deal with the car's bobins. Bobin is an increase in transformer. To create a spark that settles the working mixture, a high voltage is required, which we get from the car battery, previously turning the battery direct current to variable using the interrupter. It is easy to figure out that with an accuracy of the loss of energy going on the heating of the transformer, the current is reduced by increasing the voltage, and vice versa.

Welding machines require lower transformers. For welding, very strong currents are needed, and the transformer of the welding machine has only one output round.

You probably paid attention to the fact that the core of the transformer is made of fine leafs of steel. This is done in order not to lose energy when the voltage is converted. In the sheet material, the vortex currents will play a smaller role than in solid.

At home you are dealing with small transformers. As for powerful transformers, they are huge structures. In these cases, the core with windings is placed in the tank filled with cooler oil.

Electricity transmission

Electricity consumers are available everywhere. It is produced in relatively few places close to the sources of fuel and hydroresours. Therefore, there is a need to transmit electricity to distances that are sometimes reaching hundreds of kilometers.

But electricity transmission over long distances is associated with noticeable losses. The fact is that, passing along the power lines, the current heats them. In accordance with the Law of Joule - Lenza, the energy spent on the heating of the wire wires is determined by the formula

where R is the line resistance. With a high length of the line, the transmission of energy can be generally economically disadvantageous. To reduce losses, it is possible, of course, to follow the way to reduce the resistance R line by increasing the cross-sectional area of \u200b\u200bthe wires. But to reduce R, for example, 100 times you need to increase the mass of the wire is also 100 times. It is clear that it is impossible to allow such a large expenditure of expensive non-ferrous metal, not to mention the difficulties of fixing heavy wires in high masts, etc. Therefore, energy losses in the line are reduced by another: decrease in current in the line. For example, a current decreases 10 times reduces the amount of heat excreted in heat conductor 100 times, i.e. the same effect is achieved as from the cycling weighting of the wire.

Since the current power is proportional to the operation of the current for voltage, then to save the transmitted power, you need to increase the voltage in the transmission line. Moreover, the longer the transfer line, the more profitable to use a higher voltage. So, for example, in the high-voltage line of the transfer Volzhskaya HPP - Moscow use voltage of 500 square meters. Meanwhile, alternating current generators are built on voltages that do not exceed 16-20 square meters. Since higher voltage would require making more complex special measures to isolate windings and other parts of generators.

Therefore, in large power plants, there are boost transformers. The transformer increases the voltage in the line at the same time, as long as the current is reduced. Power loss is small.

To directly use electricity in the engine drives of machines, in the lighting network and for other purposes, the voltage at the ends of the line should be reduced. This is achieved by lowering transformers. Moreover, usually lowering voltage and, accordingly, an increase in the current flow occurs in several stages. At each stage, the tension is becoming less and less, and the territory covered by the electrical network is increasingly. The transmission and distribution scheme is shown in the figure.

The electrical stations of a number of regions of the country are connected by high-voltage transmissions, forming a common power grid to which consumers are connected. Such an association is called the power system. The power system ensures uninterrupted energy to consumers regardless of their location.

Use of electricity.

The use of electric power industry in various fields of science.

Microprocessors accelerated the growth of robotics. Most of the robots used now apply to the so-called first generation, and are used in welding, cutting, pressing, coating, etc. The second generation robots come to replace them are equipped with devices for environmental recognition. And the third-generation "intellectuals" robots will "see", "feel", "hear". Scientists and engineers among the most priority spheres of robots are called nuclear power, the development of space space, transport, trade, warehousing, medical care, waste recycling, mastering the wealth of the oceanic bottom. The main part of robots operate on electrical energy, but an increase in electricity consumption by robots is compensated by a decrease in energy consumption in many energy-intensive industrial processes by introducing more rational methods and new energy-saving technological processes.

Not bypassed science and scope. With the development of the HTR, the expansion of the production and non-productive spheres of human activity, management is becoming an increasingly important role in improving their effectiveness. From a kind of art that has recently founded on experience and intuition, management today has turned into science. The science of managing, on the general laws of obtaining, storage, transmission and processing of information is called cybernetics. This term comes from the Greek words "steering", "feeding". It is found in the writings of ancient Greek philosophers. However, his new birth happened in 1948, after the release of the book of American scientist Norbert Wiener "Cybernetics".

Before the start of the "cybernetic" revolution, there was only paper informatics, the main means of perception of which remained a human brain, and which did not use electricity. The "cybernetic" revolution spawned fundamentally different - machine informatics, corresponding to the giant increased information flow, the source of energy for which the electricity is served. Completely new means of obtaining information, its accumulation, processing and transmission, in the aggregate forming a complex information structure. It includes ACS (automated control systems), information banks of data, automated information bases, computing centers, video terminals, copying and photothelphs, nationwide information systems, satellite and high-speed optical communication systems - all this unlimited expanded the scope of electricity utilization.

Many scientists believe that in this case we are talking about a new "information" civilization coming to the change of the traditional organization of the industrial type society. Such specialization is characterized by the following important features:

· Wide dissemination of information technology in material and intangible production, in the field of science, education, health care, etc.;

· The presence of a wide network of various data banks, including public use;

· Transformation of information into one of the most important factors of economic, national and personal development;

· Free circulation of information in society.

Such a transition from industrial society to the "information civilization" became possible largely due to the development of energy and ensure the use of energy efficient in transmission and use - electrical energy.

Electricity in production.

Electricity in everyday life.

Electricity to everyday an integral assistant. Every day we have the case with her, and probably no longer imagine your life without it. Remember when the last time turned off the light, that is, the electricity did not go to your house, remember how you swear that you do not have time and you need a light, you need a TV, kettle and a bunch of other electrical appliances. After all, if we de-energize us forever, then we will just return to those long-standing times when the food was cooked on the bore and lived in cold wigvamams.

The significance of the electricity in our lives can be a whole poem, it is so important in our lives and so we are accustomed to her. Although we already not notice that she comes to our house, but when it is turned off, it becomes very comfortable.

Appreciate electricity!

Bibliography.

1. Textbook S.V. Gromova "Physics, Grade 10". Moscow: Enlightenment.

2. Encyclopedic dictionary of young physics. Structure. V.A. Chuyanov, Moscow: Pedagogy.

3. Ellion L., Wilkens at .. Physics. Moscow: Science.

4. Koltun M. World of Physics. Moscow.

5. Energy sources. Facts, problems, solutions. Moscow: Science and Technology.

6. Non-traditional energy sources. Moscow: Knowledge.

7. Yudasin LS. Energy: problems and hopes. Moscow: Enlightenment.

8. Podgorny A.N. Hydrogen power. Moscow: Science.

Popular

Peoples living in the Irkutsk region Hunter without a rifle and game

« Tofa is a unique nationality, these people live only in the Nizhneudinsky district of the Irkutsk region. There are only 678 people left them. It would seem that the authorities ... »

Case Born and Right Threat

« Member of the gang Born legend about Robin Hood appeared from time immemorial when each oppressed wanted to believe in justice and the opportunity ... »

Singer, Komsomolka, Beauty: The mysterious wife of the dictator of North Korea

« The first during the reign of Kim Jong Yana in the DPRK, the Inter-Key Summit began in the morning on Friday in the border point of Phanmundja, located in ... »