Power supply to the Dubossary home appliances plant using energy-saving outdoor lighting systems

Introduction

The creation of any industrial power supply system begins with an assessment of future electrical loads. The efficiency of the selected scheme and elements of the power supply system of industrial enterprises will depend on the qualitative assessment of loads on the network in the future. When evaluating electrical loads at enterprises, it is necessary to take into account the reliability of power supply to electric receivers, power, voltage, operating mode, current type.

Currently, power supply to industrial enterprises is carried out on three-phase alternating current. To power several DC receivers, it is necessary to use converter substations equipped with converter units (mercury rectifiers, semiconductor rectifiers motors, generators).

An alternating three-phase current with a frequency of 50 Hertz is the main type of current in the power supply of industrial enterprises. High-frequency and high-frequency installations are used in power supply of industrial enterprises for induction and dielectric heating. AC current of reduced frequency is used to supply some melting plants (ore recovery, electric slag remelting, etc.).

In addition to dividing consumers depending on operation modes, it is also necessary to take into account asymmetry of loads or non-uniformity of phase loads. Symmetric receivers are three-phase furnaces, electric motors and other receivers characterized by symmetric load of all three phases. Asymmetric receivers used in the power supply of industrial enterprises include electric lighting, single-phase and two-phase electric furnaces, single-phase welding transformers, etc.

According to the degree of reliability of power supply, electric receivers can be divided into the following categories.

1st category: according to the rules of electrical installations, electric receivers belong to the first category, a break in the power supply of which can lead to a danger to people's life and health, as well as cause significant damage to the national economy. As a rule, when power is supplied to industrial enterprises, damage is expressed in equipment damage, mass scrap of products, etc. Such electric receivers are necessarily provided with power from 2 independent power sources, and a break in their electricity supply can be allowed for the period of automatic switching on of the reserve. It should be mentioned that an independent source is called the source at which the voltage remains if it disappears on other sources.

2nd category. This category includes electric receivers, whose break in the power supply of industrial enterprises is associated with a massive decrease in output, the downtime of mechanisms or people. For them, as for category 1, power redundancy is also required, but at the same time there are power interruptions for the time required for manual switching to a backup source.

3rd category. It includes all other electric receivers operated in non-essential warehouses, auxiliary workshops, non-mass production workshops. For them, a power break of not more than 24 hours is allowed, required for repair or replacement of the damaged component of the power supply system of industrial enterprises.

In addition, at some enterprises as part of electric receivers of the 1st category there are special groups whose power supply disruption entails serious consequences, such as fires, explosions, and deaths. They are provided with power redundancy from the 3rd independent source.

Design of internal power supply system of the enterprise

Let's consider two options of capacity and number of shop TPs, depending on the location of compensating devices - on the high side of the TP or on the low. It is necessary to choose a more advantageous option taking into account losses in transformers.

Implementation of an automated electricity metering system

The main consumer of energy resources in the domestic economy is traditionally industry. If in the Soviet era the cost of energy resources was minimal, and the organization of truly effective accounting for their consumption was actually unprofitable economically, now the situation has changed fundamentally. Currently, energy expenditures account for an average of 20% to 30% of the cost of production (for energy-intensive industries - up to 40%). Therefore, energy conservation in industry today comes to the fore.

Energy saving of industrial enterprises is possible only if there is reliable information on the amount of energy consumed by the enterprise. In this regard, the organization of effective energy accounting is of particular importance. Its main goal is to accurately determine the level of energy consumption of the enterprise as a whole and its individual divisions. This makes the relationship with energy suppliers as transparent as possible. In addition, the accounting of electricity at the enterprise makes it possible to identify problem areas and technological chains where unjustifiably high energy consumption is carried out. This allows you to develop and implement energy conservation measures, as well as evaluate their effectiveness.

In industry, various measures can be used to reduce energy costs. These include:

Introduction of new production technologies that reduce energy consumption;

reduction of non-production power consumption;

modernization of used equipment;

alternative sources of electricity generation;

measures to improve the energy efficiency of industrial buildings, etc.

Previously used systems for instrument metering of electricity and other energy resources, based on visual reading of the readings of traditional metering devices, today have already hopelessly outlived themselves. They do not allow for effective simultaneous accounting at numerous production facilities located geographically, are characterized by low accuracy and reliability, and are largely dependent on the human factor. Accordingly, it is possible to talk about efficient energy saving only if automated energy accounting is used at the enterprise.

To organize such accounting, an automated system of commercial accounting of energy resources (ASKUE) is used, which provides remote collection of data from metering devices, transfers them to the upper level, where information is processed, data are prepared for analysis of consumption and commercial settlements with energy suppliers.

The ASKUE system has a hierarchical structure consisting of three levels:

lower level - primary meters (smart meters);

medium level - data collection and transmission devices (DRC), which accumulate information from metering devices and transfer it to the upper level;

the upper layer is a server that collects data from all DRC with its subsequent processing.

The implementation of ASKUE at the enterprise makes it possible to ensure accurate automated accounting of energy consumption and provides analytical information necessary for the development and implementation of energy conservation measures. As a result, such systems significantly reduce energy acquisition costs.

11.1. Economic impact and functions of ASCUE

Economic effect of ASKUE implementation at the enterprise:

- reduction of energy costs due to switching to zone rates;

- control of actually consumed capacity and reduction of declared (contractual) capacity;

- control of energy consumption of subcomponents;

- control of energy consumption of individual workshops, the possibility of calculating the share of energy costs in the cost of products;

- reduction of information processing costs due to automation of data collection and delivery processes, report generation;

- improving accounting accuracy due to revision of metering devices and replacement of old measuring transformers and counters with modern and more accurate ones.

Functions, system quality:

- automatic collection of information from metering devices

- survey with a period of 3 minutes, 30 minutes, hour, day, as well as cyclic survey of "instantaneous" values;

- direct access channel to the counter, possibility of polling by the producer program;

- support of wireless communication channels; data transmission via GPRS, support of dynamic IPaddresses;

- DRC survey from the Internet, including GPRS;

- Access to webinterface data.

11.2. Option to build a system based on a data collection and transmission device

ASCUE based on data collection and transmission device (DRC). The system is constructed as a hierarchical structure of three levels.

The first level (information and measurement complex, IIK) includes measuring transformers and a metering device. Three-phase interval counters are used.

The second level (information-computing complex, IVCE, is a industrial controller (DRC), which consolidates information on a group of electrical installations.

The third level (information-computing complex, IVC) includes an ASKUE server and automated operator workstations (AWS). IVC, as a rule, is based on server solutions.

The set of IVC programs includes a polling server, data visualization tools, a report server, data import/export tools, and administration tools. Software is selected based on system specifications, customer preferences, usability and customization.