What are the losses in the energy sector. Initial conditions for calculations
The concept of loss in power grids means the difference between the transferred energy from the energy source and the accounted consumed electricity of the consumer himself. There are many reasons for the loss of electricity: poor insulation of conductors, very large loads, theft of unaccounted electricity. Our article will tell you about the types and causes of electricity losses, what methods can be taken to prevent it.
Distance from energy source to consumers
How to determine losses in power networks, as well as compensate for material damage, will help the legislative act that regulates the accounting and payment of all types of losses. Decree of the Government of the Russian Federation of December 27, 2004 N 861 (as amended on February 4, 2017) "On approval of the Rules for non-discriminatory access to transmission services electrical energy and provision of these services…” p. VI.
Loss of electricity most often occurs during the transmission of electricity to long distances, one of the reasons is the voltage consumed by the consumer itself, i.e. 220V or 380V. In order to conduct electricity of this voltage from power plants directly, you will need wires with a large cross-sectional diameter, such wires are very difficult to hang on power lines due to their weight. Laying such wires in the ground will also be costly. To avoid this, high-voltage power lines are used. For calculations, the following formula is used: P \u003d I * U, where P is the current power, I is the current, U is the voltage in the circuit.
If you increase the voltage during the transmission of electricity, then the current will decrease, and wires with a large diameter will not be needed. But at the same time, losses are formed in transformers and they need to be paid. When energy is transferred with such a voltage, there are big losses also due to the wear of the conductor surfaces, tk. the resistance increases. The same losses are weather(humidity), the leakage then occurs on the insulators and on the crown.
When the electricity arrives at the end point, the consumers must convert the electricity into 6-10 kV voltage. From there it is distributed via cables to different points consumption, after which it is again necessary to convert the voltage to 0.4kV. And this is again a loss. Electricity is supplied to residential premises with a voltage of 220V or 380V. It should be borne in mind that transformers have their own efficiency, they work under a certain load. If the power of electrical consumers is more or less than the declared one, then the losses will grow in any case.
Another factor in power loss is an incorrectly selected transformer. Each transformer has a declared power rating and if more is consumed, then it produces either less voltage or may even break down. Since the voltage in such cases decreases, electrical appliances increase electricity consumption.
Losses in domestic conditions
After receiving the required voltage of 220V or 380V, the consumer bears the loss of electricity. Losses at home occur for the following reasons:
- Exceeding declared electricity consumption
- Capacitive load type
- Inductive load type
- Interference in the operation of appliances (switches, plugs, sockets, etc.)
- Use of old electrical equipment and lighting items.
How to reduce energy losses in houses and apartments? First, check that the size of the cables and wires is sufficient for the load to be transferred. Usually, a cable is used for lighting lines, for outlet lines - a cable with a cross section of 2.5 sq. mm, and for especially "gluttonous" electrical appliances - 4 sq. mm. If nothing can be done, then energy will be wasted on heating the wires, which means that their insulation may be damaged, and the chance of fire increases.
Second, bad contact. Knife switches, starters and switches help to avoid the loss of electricity if they are made of materials that are resistant to oxidation and metal corrosion. The slightest trace of oxide increases the resistance. For good contact, one pole must fit snugly against the other.
The third is the reactive load. Reactive load is carried by all electrical appliances, except for incandescent lamps, old electric stoves. The resulting magnetic induction leads to resistance to the passage of current through induction. At the same time, this electromagnetic induction helps the current to pass over time and adds part of the energy to the network, which forms eddy currents. Such currents give incorrect data to electricity meters, and also reduce the quality of the supplied energy. With capacitive loading, eddy currents also distort the data, which can be dealt with using special reactive energy compensators.
The fourth point is the use of incandescent lamps for lighting. Most of energy goes to heat the filaments, the environment, and only 3.5% is spent on lighting. Modern LED bulbs have been widely used, their efficiency is much higher, for LEDs it reaches 20%. Life time modern lamps at times different from incandescent lamps, which can last only a thousand hours.
All of the above methods to reduce the load on electrical wiring in residential premises help to reduce losses in the power grid. All methods are detailed to help household users who are unaware of possible losses. At the same time, professionals work at power plants and substations, who also study and solve problems with power losses.
23/01/2014One of the most important problems for the energy industry today is the loss of electricity during transportation through networks. For consumers, they have a negative impact on the quality of electricity supply, and for energy companies - on their economy. Also, energy losses negatively affect the functioning of the entire power supply system. They are called actual or reporting. Such losses represent the difference in electricity between that which entered the network and that which was supplied to consumers.
Energy losses can be classified according to various components: the nature of the losses, the voltage class, the group of elements, the production unit, etc. We will try to separate them according to the physical nature and specifics of the methods of determination. quantitative value. These parameters can be distinguished:
1. Losses of a technical nature. They occur during the transmission of energy through power grids and are caused by physical processes that occur in wires and equipment.
2. Electricity, which is spent on ensuring the operation of substations and the activities of personnel. Such energy is determined by meters installed on auxiliary transformers of power plants.
3. Losses due to errors in its measurement by instruments.
4. Losses of a commercial nature. These are the theft of energy, differences in meter readings and payments made by consumers. They are calculated by the difference between the reported losses and the amount of electricity losses indicated by us in the first three paragraphs. Energy losses that occur due to theft depend on the human factor. This is - . But the first three components occur as a result of the technological needs of the process, it is about them that we will now discuss.
Electricity is a product that does not require additional resources for transportation on the way from the producer to the consumer, but consumes itself. This process is inevitable. Indeed, when moving vehicles from point A to point B, we spend gasoline, gas or electric motor energy and take it for granted. We never say that during the transportation of the cargo “the loss of gasoline amounted to 10 liters”, the expression “gasoline consumption amounted to 10 liters” is usually used. The amount of electricity used for transportation, as in the example with cars, we call losses. The essence of this term, in the view of ignorant people, is a poorly organized process of transporting electricity, which can be associated with losses during the transportation of potatoes or grain. To see the opposite, consider an example.
When moving, electricity travels hundreds of kilometers; such a process cannot occur without certain costs. In order to more clearly demonstrate the picture, let's compare the transmission of electrical energy with the transmission of thermal energy, which are essentially very similar. Thermal energy also loses a part of itself during transportation. For example, through pipe insulation, which cannot be perfect. Such losses are inevitable, they are not completely eliminated, but only reduced by improving the insulation, replacing pipes with more advanced ones. The process requires considerable material costs. At the same time, useful work aimed at transporting the thermal energy itself is not performed by such losses. Transportation through pipes is carried out due to the energy consumed pumping stations. In cases of pipe bursts and leaks hot water outside, the term "losses" can be applied in full. Losses in the transmission of electrical energy are of a slightly different nature. They commit useful work. As in the water example, electricity cannot "leak" out of the wires.
The electrical network is a converter and distribution system. Its parts are interconnected by wires and cables. On hundreds and thousands of kilometers that separate the energy producer and the consumer, there are transformation and branching systems, which are switching devices and conductors. The current that flows in these conductors is the orderly movement of electrons. When moving, they collide with obstacles of the crystalline structure of the substance. In order to overcome this barrier, the electron needs to spend a certain amount of its internal energy. The latter turns into heat energy and disappears without a trace in environment. This is the "loss" of electrical energy.
But the indicated reason for which they occur is not the only one. On a long journey, energy meets with large quantity switching devices in the form of starters, switches, switches and the like. They consist of power contacts that have a higher resistance than homogeneous conductors - wires or cables. During operation, wear of the contacts occurs, as a result, the electrical conductivity worsens, and as a result, the loss of electricity. Contacts in places where there is a wire connection with all kinds of devices, devices and systems are also important in this process. In total, all connection points represent a significant amount of energy loss. Energy losses can be exacerbated by untimely prevention and control of sections of power networks. One more reason for the leakage of electricity can be called: no matter how well the wires are insulated, a certain part of the current still gets to the ground.
In places of outdated electrical insulation, the losses are naturally aggravated. Their number is also affected by how overloaded the equipment is - transformer substations, distribution points, cable and overhead lines. It can be concluded that timely monitoring of the condition of the equipment, the necessary repair and replacement, compliance with the requirements of operation, reduce energy losses. The increase in the number of losses is evidence of problems in the network that require technical re-equipment, improvement of methods and means of operation.
International experts have determined that energy losses during transmission through electric networks are considered appropriate if their rate is not higher than 4-5%. In the case when they reach 10%, they should be considered the maximum allowable. AT different countries scores can vary significantly. It depends on the principles of energy system development. The determining factors are the orientation towards large power plants and long power lines or low-power stations located in load centers, etc. In countries such as Germany and Japan, the loss rate is 4-5%. In countries where the territory is long and energy system focused on powerful power plants the loss figure is close to 10%. Norway and Canada are examples of this. Energy generation in each country is unique. Therefore, to apply the indicators of any country to Russian conditions completely pointless.
The situation in Russia suggests that the level of losses can only be justified by calculations for specific circuits and network loads. The loss rate is set by the Ministry of Energy for each grid company separately. AT different regions these numbers are different. The average figure for Russia was 10%. The importance of the problem is growing every year. In this regard, a lot of work is being done to analyze losses and reduce them, effective methods calculation. Thus, AO-Energo presented a whole set of calculation of all components of losses in networks of all categories. This complex received a certificate of conformity, which was approved by the CDU of the UES of Russia, the Glavgosenergonadzor of Russia and the Department of Electrical Grids of RAO UES of Russia. The setting of tariffs for electricity also depends on the norms of losses in this area. Tariffs are regulated by federal and regional energy commissions. Organizations are required to justify the level of energy loss that is considered appropriate for them and include it in the tariffs. The energy commissions, in turn, analyze these justifications and either accept them or correct them. Leader in the minimum energy losses in the country - the Republic of Khakassia. Here the figure is 4%.
Introduction
Literature review
1.2 Load power losses
1.3 No-load losses
1.4 Climate losses of electricity
2. Methods for calculating electricity losses
2.1 Methods for calculating electricity losses for various networks
2.2 Methods for calculating electricity losses in distribution networks 0.38-6-10 kV
3. Programs for calculating electricity losses in distribution electrical networks
3.1 Need for calculation technical losses electricity
3.2 Application of software for calculating electricity losses in distribution networks 0.38 - 6 - 10 kV
4. Regulation of electricity losses
4.1 The concept of the loss standard. Methods for setting standards in practice
4.2 Loss specifications
4.3 The procedure for calculating the standards for electricity losses in distribution networks 0.38 - 6 - 10 kV
5. An example of calculating electricity losses in distribution networks 10 kV
Conclusion
Bibliography
Introduction
Electrical energy is the only type of product that does not use other resources to move it from the places of production to the places of consumption. For this, part of the transmitted electricity itself is consumed, so its losses are inevitable, the task is to determine their economically justified level. Reducing electricity losses in electrical networks to this level is one of the important areas of energy saving.
During the entire period from 1991 to 2003, the total losses in the energy systems of Russia grew both in absolute terms and as a percentage of electricity supplied to the grid.
The growth of energy losses in electrical networks is determined by the action of quite objective laws in the development of the entire energy sector as a whole. The main ones are: the trend towards the concentration of electricity generation at large power plants; continuous growth of loads of electric networks, associated with a natural increase in loads of consumers and a lag in growth rates bandwidth networks on the growth rates of electricity consumption and generating capacities.
In connection with the development of market relations in the country, the importance of the problem of electricity losses has increased significantly. The development of methods for calculating, analyzing power losses and choosing economically feasible measures to reduce them has been carried out at VNIIE for more than 30 years. To calculate all components of electricity losses in the networks of all voltage classes of AO-energos and in the equipment of networks and substations and their regulatory characteristics, a software package has been developed that has a certificate of conformity approved by the CDU of the UES of Russia, the Glavgosenergonadzor of Russia and the Department of Electric Grids of RAO "UES of Russia".
Due to the complexity of calculating losses and the presence of significant errors, in recent times special attention is paid to the development of methods for normalizing power losses.
The methodology for determining loss standards has not yet been established. Even the principles of rationing have not been defined. Opinions on the approach to rationing range widely - from the desire to have an established fixed standard in the form of a percentage of losses to control over "normal" losses with the help of ongoing calculations according to network diagrams using appropriate software.
According to the received norms of electricity losses, tariffs for electricity are set. Tariff regulation is entrusted to the state regulatory bodies FEK and REC (federal and regional energy commissions). Energy supply organizations must justify the level of electricity losses that they consider appropriate to include in the tariff, and energy commissions should analyze these justifications and accept or correct them.
This paper considers the problem of calculation, analysis and regulation of electricity losses from modern positions; the theoretical provisions of the calculations are presented, a description of the software that implements these provisions is given, and the experience of practical calculations is presented.
Literature review
The problem of calculating electricity losses has been worrying power engineers for a very long time. In this regard, very few books on this topic are currently being published, because little has changed in principle device networks. But it produces enough a large number of articles where old data are clarified and new solutions are proposed for problems related to the calculation, regulation and reduction of electricity losses.
One of the latest books published on this topic is Zhelezko Yu.S. "Calculation, analysis and regulation of electricity losses in electrical networks" . It most fully presents the structure of electricity losses, loss analysis methods and the choice of measures to reduce them. The methods of normalization of losses are substantiated. Described in detail software, which implements methods for calculating losses.
Earlier, the same author published the book "Selection of Measures to Reduce Electricity Losses in Electric Networks: A Guide for Practical Calculations". Here, the greatest attention was paid to methods for calculating electricity losses in various networks and the use of one or another method depending on the type of network, as well as measures to reduce electricity losses, was justified.
In the book Budzko I.A. and Levina M.S. "Power supply of agricultural enterprises and settlements" the authors examined in detail the problems of power supply in general, focusing on distribution networks that feed agricultural enterprises and settlements. The book also provides recommendations on organizing control over electricity consumption and improving accounting systems.
Authors Vorotnitsky V.E., Zhelezko Yu.S. and Kazantsev V.N. in the book "Electricity losses in electrical networks of power systems" considered in detail general issues related to reducing electricity losses in networks: methods for calculating and predicting losses in networks, analyzing the structure of losses and calculating their technical and economic efficiency, planning losses and measures to reduce them.
In the article by Vorotnitsky V.E., Zaslonov S.V. and Kalinkini M.A. "The program for calculating the technical losses of power and electricity in distribution networks 6 - 10 kV" describes in detail the program for calculating the technical losses of electricity RTP 3.1 Its main advantage is ease of use and easy-to-analyze conclusion of the final results, which significantly reduces personnel labor costs for calculation.
Article Zhelezko Yu.S. "Principles of regulation of electricity losses in electrical networks and calculation software" is devoted to the actual problem of regulation of electricity losses. The author focuses on the purposeful reduction of losses to an economically justified level, which is not ensured by the existing practice of rationing. The article also makes a proposal to use the normative characteristics of losses developed on the basis of detailed circuit calculations of networks of all voltage classes. In this case, the calculation can be made using the software.
The purpose of another article by the same author entitled "Estimation of electricity losses due to instrumental measurement errors" is not to clarify the methodology for determining the errors of specific measuring instruments based on checking their parameters. The author in the article assessed the resulting errors in the system for accounting for the receipt and release of electricity from the network of an energy supply organization, which includes hundreds and thousands of devices. Special attention paid to the systematic error, which at present is an essential component of the loss structure.
In the article Galanova V.P., Galanova V.V. "Effect of the quality of electricity on the level of its losses in the networks" paid attention to the actual problem of the quality of electricity, which has a significant impact on the loss of electricity in the networks.
Article by Vorotnitsky V.E., Zagorsky Ya.T. and Apryatkin V.N. "Calculation, regulation and reduction of electricity losses in urban electrical networks" is devoted to clarifying existing methods for calculating electricity losses, normalizing losses in modern conditions, as well as new methods to reduce losses.
The article by Ovchinnikov A. "Electricity losses in distribution networks 0.38 - 6 (10) kV" focuses on obtaining reliable information about the operation parameters of network elements, and above all about the load of power transformers. This information, according to the author, will help to significantly reduce the loss of electricity in networks of 0.38 - 6 - 10 kV.
1. Structure of electricity losses in electrical networks. Technical losses of electricity
1.1 Structure of electricity losses in electrical networks
During the transmission of electrical energy, losses occur in each element of the electrical network. To study the loss components in various elements network and assess the need for a particular measure aimed at reducing losses, an analysis of the structure of electricity losses is performed.
Actual (reported) electricity losses Δ W Rep is defined as the difference between the electricity supplied to the network and the electricity released from the network to consumers. These losses include components of a different nature: losses in network elements that are purely physical in nature, the consumption of electricity for the operation of equipment installed at substations and ensuring the transmission of electricity, errors in fixing electricity by metering devices and, finally, theft of electricity, non-payment or incomplete payment meter readings, etc.
In electrical networks, there are large actual losses electricity.
Of the total number of losses, the losses in the power transformers of MUP "PES" are approximately 1.7%. Losses of electricity in power lines with a voltage of 6-10 kV are about 4.0%. Electricity losses in 0.4 kV networks are 9-10%.
An analysis of the dynamics of absolute and relative losses of electricity in the networks of Russia, their modes of operation and load shows that there are practically no good reasons growth of technical losses caused by the physical processes of transmission and distribution of electricity. The main reason for the losses is an increase in the commercial component.
The main causes of technical losses are:
Deterioration of electrical equipment;
Use of obsolete types of electrical equipment;
Non-compliance of the electrical equipment used with the existing loads;
Non-optimal steady state conditions in distribution networks by levels
voltage and reactive power.
The main reasons for commercial losses are:
Unacceptable errors in electricity measurements (inconsistency of metering devices with accuracy classes, inconsistency of current transformers with existing loads, violation of verification deadlines and malfunctions of electricity metering devices);
Use of imperfect methods for calculating the amount of electricity supplied in the absence of metering devices;
Imperfection of methods for taking readings from metering devices and issuing receipts directly by subscribers in the domestic sector;
Contractless and unaccounted for electricity consumption (theft);
Distortion of volumes of electricity supply to consumers.
ACTUAL POWER LOSS
MUP "PODIL'SK ELECTRIC NETWORK"
STRUCTURE OF ACTUAL POWER LOSSES
 |
|
| |||||||||||
Technological losses of electricity (hereinafter - TPE) during its transmission through the electric networks of TSOs include technical losses in the lines and equipment of electric networks due to physical processes occurring during the transmission of electricity in accordance with technical specifications and modes of operation of lines and equipment, taking into account the consumption of electricity for substations' own needs and losses due to permissible errors in the electricity metering system. The volume (quantity) of technological losses of electricity in order to determine the standard for technological losses of electricity during its transmission through electric networks is calculated in accordance with the instructions for organization in the Ministry of Energy Russian Federation work on the calculation and justification of the standards for technological losses of electricity during its transmission through electric networks, approved by order No. 000 dated 01.01.2001.
Methods for calculating the standard losses of electrical energy
Basic concepts
1. Reception of electrical energy in the network
2. Output of electrical energy from the network
4. Actual (reported) electricity losses in absolute units
6. Technical losses of electricity
9. Standard for technological losses of electricity in absolute units
11. Regulatory losses of electricity, absolute
Calculation of losses in electrical network equipment
ü Electricity losses in the overhead line
ü Electricity losses in the cable line
ü Electricity losses in transformers (autotransformers)
ü Electricity losses in current-limiting reactors
 |
Semi-permanent power losses
Ü losses in steel of power transformers and autotransformers;
Ü losses in the steel of shunt reactors;
Ü corona losses in overhead lines 110 kV and above;
Ü losses in capacitor banks (BSC) and static thyristor compensators;
Ü losses in synchronous compensators (SC);
Ü losses in surge arresters;
Ü electricity losses in direct connection meters;
Ü losses in measuring current and voltage transformers;
Ü losses in the insulation of cable lines;
Ü losses from leakage currents through insulators of overhead lines;
Ü losses in connecting wires and busbars of substations;
Ü electricity consumption for ice melting;
Ü Electricity consumption for auxiliary needs of substations, taking into account losses in steel and copper of transformers for auxiliary needs, if accounting does not coincide with the boundary of the balance sheet.
Variable electricity losses
Ü load losses of electricity in transformers and autotransformers
Ü load losses of electricity in air and cable lines
Ü electricity losses in current-limiting reactors
Variable Loss Calculation Methods
The method of operational calculations of steady-state modes using data from operational dispatch complexes (OIC)
Method for calculating losses according to the data of the calculated day (using regime data for a typical day)
Method for calculating losses by average loads
Mode Loss Calculation Method maximum loads network using the number of hours of the greatest power losses
Estimated calculation methods
Operational calculation method
Electricity losses over a time interval in a three-winding transformer
Settlement day method
Losses of electricity for the billing period
Chart Shape Factor
 |
 |
Average load method
Losses of electricity in electrical networks are the most important indicator of the efficiency of their work, a clear indicator of the state of the electricity metering system, the efficiency of energy sales activities of energy supply organizations. This indicator more and more clearly indicates the accumulating problems that require urgent solutions in the development, reconstruction and technical re-equipment of electrical networks, the improvement of methods and means of their operation and management, in increasing the accuracy of electricity metering, the efficiency of collection Money for electricity supplied to consumers, etc. According to international experts, the relative losses of electricity during its transmission and distribution in the electric networks of most countries can be considered satisfactory if they do not exceed 4-5%. Losses of electricity at the level of 10% can be considered the maximum allowable from the point of view of the physics of electricity transmission through networks. It is becoming more and more obvious that the sharp aggravation of the problem of reducing electricity losses in electric networks requires an active search for new ways to solve it, new approaches to the selection of appropriate measures, and most importantly, to the organization of work to reduce losses.
Due to the sharp reduction in investments in the development and technical re-equipment of electrical networks, in improving the systems for managing their modes, electricity metering, a number of negative trends have arisen that adversely affect the level of losses in networks, such as: outdated equipment, physical and obsolescence of electricity metering , inconsistency installed equipment transmitted power.
It follows from the above that against the background of ongoing changes in the economic mechanism in the energy sector, the economic crisis in the country, the problem of reducing electricity losses in electric networks has not only not lost its relevance, but, on the contrary, has moved into one of the tasks of ensuring financial stability energy supply organizations.
Some definitions:
Absolute losses of electricity - the difference between electricity supplied to the electrical network and usefully supplied to consumers.
Technical losses of electricity - losses caused by the physical processes of transmission, distribution and transformation of electricity, are determined by calculation.
Technical losses are divided into conditionally constant and variable (depending on the load).
Commercial electricity losses are losses defined as the difference between absolute and technical losses.
STRUCTURE OF COMMERCIAL POWER LOSSES
Ideally, commercial electricity losses in the electrical network should be zero. It is obvious, however, that in real conditions, supply to the network, useful supply and technical losses are determined with errors. The differences between these errors are in fact the structural components of commercial losses. They should be minimized as far as possible through the implementation of appropriate measures. If this is not possible, it is necessary to make adjustments to the readings of electric meters to compensate for systematic errors in electricity measurements.
Errors in measurements of electricity supplied to the network and usefully supplied to consumers.
The error in measuring electricity in the general case can be divided into many components. Let's consider the most significant components of the errors of measuring complexes (MC), which may include: current transformer (CT), voltage transformer (VT), electricity meter (SE), connection line ESS to TN.
The main components of the measurement errors of the electricity supplied to the network and usefully supplied electricity include:
measurement errors of electricity in normal conditions
IC work, determined by accuracy classes ТТ, ТН and СЭ;
additional errors in electricity measurements in real operating conditions of the IC, due to:
underestimated against the normative load power factor (additional angular error); .
the effect on the SE of magnetic and electromagnetic fields of various frequencies;
underload and overload of CT, TN and SE;
asymmetry and the level of voltage supplied to the IR;
work of SE in unheated premises with unacceptably low temperature, etc.;
insufficient sensitivity of solar cells at their low loads, especially at night;
systematic errors due to the excess service life of the IC.
errors associated with incorrect connection diagrams of electricity meters, CT and VT, in particular, violations of the phasing of the connection of meters;
errors due to faulty electricity metering devices;
errors in taking readings of electric meters due to:
errors or deliberate distortions of records of indications;
non-simultaneity or non-compliance with the established deadlines for taking meter readings, violation of meter bypass schedules;
errors in determining the coefficients for converting meter readings into electricity.
It should be noted that with the same signs of the components of the measurement errors of supply to the network and productive supply, commercial losses will decrease, and with different signs they will increase. This means that from the point of view of reducing commercial losses of electricity, it is necessary to pursue an agreed technical policy to improve the accuracy of measurements of supply to the network and productive supply. In particular, if we, for example, unilaterally reduce the systematic negative measurement error (modernize the accounting system), without changing the measurement error, commercial losses will increase, which, by the way, takes place in practice.
Commercial losses due to underestimation of productive output due to shortcomings in energy sales activities.
These losses include two components: billing losses and electricity theft losses.
Billing losses.
This commercial component is due to:
inaccuracy of data on electricity consumers, including insufficient or erroneous information about concluded contracts for the use of electricity;
errors in billing, including unbilled consumers due to the lack of accurate information on them and constant monitoring of the updating of this information;
lack of control and errors in billing customers using special rates;
lack of control and accounting for adjusted accounts, etc.
Losses from electricity theft.
This is one of the most significant components of commercial losses, which is the concern of power engineers in most countries of the world.
Experience in dealing with theft of electricity in various countries summarized by a special "Expert Group. on the study of issues related to theft of electricity and unpaid bills (non-payments)". The group is organized under the Study Committee on Economics and Tariffs international organization UNIPEDE. According to a report prepared by this group in December 1998, the term "electricity theft" is used only when electricity is not metered or not fully recorded due to the fault of the consumer, or when the consumer opens the meter or disrupts the power supply system in order to reduce the meter's metering. consumption of electricity consumed.
A generalization of international and domestic experience in combating electricity theft showed that household consumers are mainly involved in these thefts. There are electricity thefts carried out by industrial and commercial enterprises, but the volume of these thefts cannot be considered decisive.
Electricity theft has a fairly clear upward trend, especially in regions with unfavorable heat supply to consumers during the cold periods of the year. L also in almost all regions in the autumn-spring periods, when the air temperature has already dropped significantly, and the heating has not yet been turned on.
There are three main groups of ways to steal electricity: mechanical, electrical, magnetic.
Mechanical methods of electricity theft.
Mechanical methods of electricity theft.
Mechanical intervention in the operation (mechanical opening) of the meter, which can take various forms, including:
drilling holes in the bottom of the case, cover or glass of the counter;
insert (in hole) various items type of film 35 mm wide, needles, etc. in order to stop the rotation of the disk or reset the counter;
moving the counter from a normal vertical position to a semi-horizontal position in order to slow down the rotation speed of the disc;
unauthorized breaking of seals, violation in the alignment of the axes of mechanisms (gears) to prevent full registration electricity consumption;
glass rolling when film is inserted, which will stop disk rotation.
Typically, mechanical interference leaves a mark on the meter, but is difficult to detect unless the meter is completely cleaned of dust and dirt and inspected by an experienced technician.
To mechanical way theft of electricity can be attributed to deliberate damage to the solar cells by household consumers, which are quite widespread in Russia, or theft of meters installed on stairwells residential buildings. As the analysis showed, the dynamics of intentional destruction and theft of meters practically coincides with the onset of cold weather with insufficient heating of apartments. In this case, the destruction and theft of meters should be considered as a kind of protest of the population against the inability of local administrations to provide normal living conditions. The aggravation of the situation with the heat supply of the population inevitably leads to an increase in commercial losses of electricity, which is already confirmed by the sad experience of the Far East and some Siberian energy systems.
Electrical methods of electricity theft.
The most common in Russia electrically Theft of electricity is the so-called “throw” on an overhead line made with a bare wire. The following methods are also widely used:
load current phase inversion;
application various types"Unwinders" for partial or complete compensation of the load current with a change in its "phase;
shunting the current circuit of the meter - installation of the so-called "short circuits";
grounding of the load neutral wire;
violation of the alternation of phase and neutral wires in a network with a grounded neutral of the supply transformer.
If the meters are connected through instrument transformers, the following can also be used:
shutdown of TT current circuits;
replacement of normal VT fuses with blown ones, etc.
Magnetic methods of theft of electricity.
The use of magnets on the outside of the meter may affect its performance. In particular, it is possible, when using old types of induction counters, to slow down the rotation of the disk using a magnet. Currently, manufacturers are trying to protect new types of meters from the influence of magnetic fields. Therefore, this way of stealing electricity is becoming more and more limited.
Other ways to steal electricity
There are a number of ways to steal electricity of purely Russian origin, for example, theft due to the frequent change of owners of a particular company with a permanent renewal of contracts for the supply of electricity. In this case, the energy sales company is not able to keep track of the change in owners and receive payment for electricity from them.
Commercial losses of electricity due to the presence of ownerless consumers.
Crisis phenomena in the country, the emergence of new joint-stock companies have led to the fact that in most energy systems in last years residential buildings, dormitories, entire residential settlements have appeared and have existed for quite a considerable time, which are not on the balance sheet of any organizations. Electricity and heat supplied to these houses, the tenants do not pay anyone. Attempts by power systems to cut off non-payers do not give results, as residents again arbitrarily connect to the grid. The electrical installations of these houses are not serviced by anyone, their technical condition threatens with accidents and does not ensure the safety of life and property of citizens.
Commercial losses due to the non-simultaneity of payment for electricity by household consumers - the so-called "seasonal component".
This very significant component of commercial electricity losses takes place due to the fact that household consumers are objectively unable to take meter readings and pay for electricity at the same time. As a rule, payments lag behind real electricity consumption, which, of course, introduces an error in determining the actual useful supply by household consumers and in calculating the actual imbalance of electricity, since the lag can be from one to three months or more. As a rule, in the autumn-winter and winter-spring periods of the year there are underpayments for electricity, and in the spring-summer and summer-autumn periods these underpayments are compensated to a certain extent. In the pre-crisis period, this compensation was almost complete, and electricity losses in a year rarely had a commercial component. Currently, autumn-winter and winter-spring seasonal underpayments for electricity are much higher in most cases than the total payment in other periods of the year. Therefore, commercial losses occur by months, quarters and for the year as a whole.
Errors in the calculation of technical losses of electricity in electrical networks.
Because commercial power losses cannot be measured. They can be calculated with some error. The value of this error depends not only on the errors in measuring the amount of electricity theft, the presence of “ownerless consumers”, and other factors discussed above, but also on the error in calculating the technical losses of electricity. The more accurate the calculations of technical losses of electricity, the more accurate the assessments of the commercial component will obviously be, the more objectively it is possible to determine their structure and outline measures to reduce them.