Design of district power supply - diploma

Summary

The diploma project is presented in the form of an explanatory note and a graphic part.

The project presents a brief description of the consumers of the area under consideration, as well as electric receivers and power sources. When designing the power supply, the following issues are solved: calculation of electrical loads, selection of the power supply scheme and power supplies, selection of the voltage of the supply networks, the number and power of transformers, the location of substations. Short-circuit currents are calculated, current-carrying parts and electrical equipment are selected and checked, relay protection and automation are selected.

In the diploma project, the replacement of street lighting with LED lamps was considered as a special issue.

The issues on organizational-economic part and life safety are considered.

Introduction

The importance of electric energy in industry continues to increase. Scientific and technological progress is based mainly on the use of electric energy in a variety of technological processes. Without electrical power, normal operation of heat, water, gas and water disposal systems is impossible.

In terms of its scientific and technical level, the reliability of our electric power industry was, and still remains the best in the world. For many years, a minimum of systemic accidents was committed compared to other countries. For the first time, we created synchronous generators with a capacity of 300, 500, 800 thousand kW, a prototype with a capacity of 1 million kW. Introduced hydrogen, water, cryogenic cooling. The voltage of power lines grew: 330, 500, 750, 1150 kV.

In terms of electricity production, the USSR ranked second in the world (after the United States).

After the collapse of the USSR, the development of the electric power industry practically ceased over the years - the system created earlier was used, the capacities were not increased and were not updated, scientific and technological progress was slowed down. To date, according to experts, equipment wear in the energy sector has reached 6070%. The shortage of electricity is the main reason for the slowdown in industrial production. There was an immediate threat of major accidents in the coming years, if not taken radical measures.

In the presidential message (2007), very large measures for the development of the electric power industry were announced. By 2020, generation capacity should grow by two-thirds, i.e. by about 115 million kW, and electricity generation in the Russian Federation from 950 to 1580 billion kW * h.

Priority is given to the development of nuclear energy until 2012. 26 NPP units shall be manufactured. In the USSR, a total of 30 blocks were manufactured.

With the current state of industry, the implementation of the presidential program is impossible. It is necessary to first restore the national economy.

Power supply systems must meet a number of requirements: economy and reliability, safety and usability, ensuring the proper quality of electricity.

At large industrial enterprises, deep bushings with a voltage of up to 220 kV began to be used; in factory networks, more and more began to use a voltage of 10 kV instead of 6 kV.

Over the past 15-17 years, the development of SES in Russia has been stalled. Scientific and technical developments have almost ceased. Increasingly imported equipment is being used with new technical solutions, in particular; smooth start of powerful electric motors, frequency control of asynchronous motors, jet power control device complete with asynchronous motor. At many industrial enterprises in Russia, the nomenclature and volume of production are not stable, which makes it difficult to optimize the use of SES and equipment.

Unlike other types of energy, electric power is generated and consumed at the same time. Accumulate it to create stock. The unity of the processes of generation, transportation and consumption of electricity explains the need for operational (dispatching) management of the country's electricity industry.

Electric energy is generated at power plants (thermal, hydraulic, nuclear, etc.). The main source of electricity for the Rostov region is the Novocherkassk state district power station. Electric machines that convert the mechanical energy of rotation of the rotors of turbines and other primary engines into electric ones are called generators. All generators of large power plants of the Russian Federation are interconnected by electric networks and have a common operating mode.

The electric network is called a set of substations and power lines. The main purpose of the electric network is the transmission and distribution of electricity among consumers. Substations convert the voltage level and distribute power. Voltage level conversion is performed by power transformers. Transformers are increasing (installed at power plants) and reducing (installed at substations). Increasing voltage at power plants is carried out in order to reduce power losses in electric networks. Voltage reduction at substations is performed for the purpose of consumers power supply.

Urban electric networks usually use a voltage of 6, 10 kV, sometimes 35 kV, as well as 0.4 kV to power their consumers. Electric power technology uses processes

conversion of various types of energy into electric energy, conversion of voltage and type of electric current, transmission, distribution and consumption of electric power.

Distribution electric networks in the balance and maintenance of 72 AOenergy power systems of the Russian Federation are 2.5 million km of overhead and cable transmission lines, 510 transformer substations 61035/0.4 kV and more than 16 thousand supply centers with a voltage of 35110 kV with a total installed capacity of approximately 400 thousand. MVA.

The main consumers of electricity are industrial enterprises, therefore the efficiency and rationality of the use of electricity in the economy of the country is determined by the system of transmission, distribution and consumption of it in industrial enterprises, that is, the power supply system - industrial electric network.

In connection with the above, serious efforts should be made to re-equip, reconstruct and develop electrical networks in order to ensure sufficient throughput, reliable and high-quality electronic supply to consumers. This task should be solved using modern highly reliable and economical equipment. If necessary, use of imported equipment.

An important achievement in the industry is the organization of serial production of 110 kV gas-insulated current transformers, vacuum switches for voltage classes up to 110 kV, anti-resonance voltage transformers 6.10 and 35 kV, packaged switchgears with vacuum switches in CSR cells, disconnectors with polymer insulators, surge limiters up to 35 kV in polymer coatings, expanded applications and mud resistant applications.

The purpose of this diploma project is to develop a power supply system for the urban area using modern methods for calculating the electric network, modern requirements for it, as well as proposals for installing new equipment in the network.

Brief characteristics of consumers, climate information

Electricity consumers located on the territory of the city are conditionally divided into two main groups: residential buildings and public utilities (schools, shops, cafes, cinemas, etc.).

Modern residential buildings are saturated with a large number of various electric receivers. These include various lighting and household appliances and power electrical equipment. Electric receivers of residential buildings are divided into electric receivers for general purpose.

Electric networks of cities provide the work of public utilities: water treatment and pumping stations, wastewater treatment stations, pumping units of heat supply systems.

The territory of the settlement by purpose is divided into the following zones:

- residential - for accommodation of residential areas, microdistricts,

public buildings and structures;

- communal warehouse - for location of warehouses, garages,

Autobaz, toll parking, etc., intended for maintenance

populated places;

- recreation places of the population - located on the boundaries of the settlement

places.

The structural unit of the settlement zone is a residential area consisting of several microdistricts united by public

the center, which includes institutions for cultural services.

The population considered in the diploma project of the residential district is about 10 thousand people, when it is built with buildings five floors high and nine floors.

The population lives in multi-storey buildings. Gas furnaces are installed in houses. In houses with nine floors there are elevator shafts, as well as central heating points.

Residential buildings and public utilities receive electricity from city networks. High-voltage receivers do not have.

The planning and development of residential areas provides the most favorable conditions for the life and recreation of the population, the upbringing and education of children. To this end, it is planned to build the necessary communal institutions. Such institutions are located taking into account the creation of a unified system for serving the population of the urban territory. In the group of residential buildings in a service radius of up to 0.3 km there are nurseries, kindergartens and sports grounds.

In the microdistrict in a radius of up to 0.5 km - schools, trade and catering enterprises, sports grounds, garages for individual cars.

In a residential area, as a rule, in a public center within a service radius of up to 1.5 km - a shopping center, wagons, trade and catering enterprises, a club, a cinema, a library, a clinic, garages for individual cars.

The norms also determine the main requirements for the placement of electrical grid structures in the city, which must be adopted in city power supply systems. Step-down substations

located in industrial and communal storage areas. The size for the substation is accepted up to 0.25 Ha.

The terrain of the surrounding area is a wavy plain dissected by shallow valleys and beams.

The climate of the region is temperate, summer is hot, dry, with a maximum July temperature of + 38 ° C. In winter, intense cooling is possible, the maximum January temperature is 33 ° C.

Precipitation falls 480 mm, of which 180 mm fall in the cold period (November-March), which in high temperatures gives the climate an arid character.

The predominant wind direction is northeast (22%) and east (22%). Lowest recurrence in the south wind

The territory of the city is assigned by high-speed wind pressure to the III district.

The territory of RES is located in the III district on ice and in the II district on atmospheric pollution.

External power supply issues

The power source is the node substation of the P10 power system located 27 kilometers from the territory of the fed area. The area is powered at 110 kV. The power of the three-phase short circuit at the VL connection point is 221 MVA.

Two single-chain VL - 110 kV are introduced into the area. The 110 kV voltage is received in the 110 kV OPC of the main lowering substation (GPP) of the area.

Systematization and

calculation of electrical loads

The initial parameters for solving complex complex technical and economic calculations arising in the design of modern enterprises are loads.

Load determination is necessary for correct selection of power of transformers, compensating devices, selection of section of wires and cables, buses, selection and acceptance of relay protection settings, calculation of losses, deviation and voltage fluctuation.

The optimal solution of power supply issues is found by drawing up several possible load options. In order to choose the most appropriate of them, it is necessary to resort to technical and economic comparison. Overstatement or understatement of loads leads to an increase in the reduced costs, underutilization of electrical equipment or underutilization of products and an increase in power losses. Therefore, the correct determination of electrical loads is a decisive factor in the design and operation of electrical networks and power supply to enterprises.

Selection of power supply scheme.

Determining the Location of Groups

The city's power supply system is a collection of electric networks of various voltages, usually (excluding megacities) voltage 22035, 6-10 and up to 1 kV. 610 kV networks are designed to distribute electricity between groups of consumers or to supply individual consumers. Such networks are commonly called urban distribution networks (RBNs). These networks are mainly designed to power public utilities in the city.

In general, GVMs include a 610 kV supply network and a direct distribution network of the same voltage. The 610 kV supply network often consists of supply lines, distribution points (RP) and direct connections between the latter.

The city's power supply system is subject to the following requirements:

1. Economic feasibility of construction and operation, i.e. a combination of relatively low equipment costs, construction and operation costs, including loss of electricity.

2. Ensuring the required quality of power supply to consumers.

The quality of the power supply is usually understood as the required

voltage level at receiver terminals.

3. Enabling the development of the network without its overgrowth

royalties.

4. Convenience and security of service.