Types of losses in electrical networks. Comprehensive measures to reduce electricity losses

Electricity losses in electrical networks are inevitable, so it is important that they do not exceed an economically justified level. Exceeding technological consumption standards indicates problems that have arisen. To correct the situation, it is necessary to establish the causes of non-target costs and choose ways to reduce them. The information collected in this article describes many aspects of this difficult task.

Types and structure of losses

Losses mean the difference between the electricity supplied to consumers and the energy actually received by them. To normalize losses and calculate their actual value, the following classification was adopted:

• Technological factor. It directly depends on characteristic physical processes, and can change under the influence of the load component, semi-fixed costs, as well as climatic conditions.
• Expenses spent on operating auxiliary equipment and providing necessary conditions for the work of technical staff.
• Commercial component. This category includes errors in metering devices, as well as other factors causing under-metering of electricity.

Below is an average graph of losses for a typical electric company.

As can be seen from the graph, the highest costs are associated with transmission via overhead lines (power lines), this accounts for about 64% of the total losses. In second place is the corona effect (ionization of air near the overhead line wires and, as a consequence, the occurrence of discharge currents between them) – 17%.

Based on the presented graph, it can be stated that the largest percentage of non-targeted expenses falls on the technological factor.

Main causes of electricity losses

Having understood the structure, let's move on to the reasons that cause inappropriate expenditure in each of the categories listed above. Let's start with the components of the technological factor:

1. Load losses occur in power lines, equipment and various elements of electrical networks. Such costs directly depend on the total load. This component includes:

• Losses in power lines are directly related to the current strength. That is why, when transmitting electricity over long distances, the principle of increasing it several times is used, which contributes to a proportional reduction in current and, accordingly, costs.
• Consumption in transformers of magnetic and electrical nature (). As an example, below is a table that shows cost data for substation voltage transformers in 10 kV networks.

Non-target consumption in other elements is not included in this category due to the complexity of such calculations and the insignificant amount of costs. For this, the following component is provided.

1. Category of semi-fixed expenses. It includes costs associated with the normal operation of electrical equipment, these include:

• Idle operation of power plants.
• Costs in equipment providing reactive load compensation.
• Other types of costs in various devices, whose characteristics do not depend on the load. Examples include power insulation, metering devices in 0.38 kV networks, measuring current transformers, surge limiters, etc.

Taking into account the last factor, the energy costs for melting ice should be taken into account.

Costs for supporting the operation of substations

Costs included in this category electrical energy on the functioning of auxiliary devices. Such equipment is necessary for the normal operation of the main units responsible for the conversion of electricity and its distribution. Costs are recorded using metering devices. Here is a list of the main consumers belonging to this category:

• ventilation and cooling systems for transformer equipment;
• heating and ventilation of the technological room, as well as internal lighting fixtures;
• lighting of areas adjacent to substations;
• battery charging equipment;
• operational circuits and monitoring and control systems;
• outdoor equipment heating systems, such as air circuit breaker control modules;
• various types of compressor equipment;
• auxiliary mechanisms;
• equipment for repair work, communication equipment, as well as other devices.

Commercial component

These costs mean the balance between absolute (actual) and technical losses. Ideally, such a difference should tend to zero, but in practice this is not realistic. This is primarily due to the characteristics of electricity meters and electricity meters installed at end consumers. It's about error. There are a number of specific measures to reduce losses of this type.

This component also includes errors in bills issued to consumers and theft of electricity. In the first case, a similar situation may arise for the following reasons:

• the contract for the supply of electricity contains incomplete or incorrect information about the consumer;
• incorrectly indicated tariff;
• lack of control over meter data;
• errors related to previously adjusted accounts, etc.

As for theft, this problem occurs in all countries. As a rule, such illegal actions are carried out by unscrupulous household consumers. Note that sometimes incidents occur with enterprises, but such cases are quite rare, and therefore are not decisive. It is typical that the peak of thefts occurs in the cold season, and in those regions where there are problems with heat supply.

There are three methods of theft (understating meter readings):

1. Mechanical. This means appropriate intervention in the operation of the device. This can be slowing down the rotation of the disk by direct mechanical impact, changing the position of the electric meter by tilting it by 45° (for the same purpose). Sometimes a more barbaric method is used, namely, the seals are broken and the mechanism is unbalanced. An experienced specialist will instantly detect mechanical interference.
2. Electric. This can be an illegal connection to an overhead line by “throwing”, a method of investing a phase of the load current, as well as the use of special devices for its full or partial compensation. In addition, there are options with shunting the current circuit of the meter or switching phase and zero.
3. Magnetic. At this method A neodymium magnet is brought to the body of the induction meter.

Almost all modern metering devices cannot be “deceived” using the methods described above. Moreover, such attempts to interfere can be recorded by the device and stored in memory, which will lead to dire consequences.

The concept of loss standard

This term means the establishment of economically sound criteria for non-target expenditure for a certain period. When standardizing, all components are taken into account. Each of them is carefully analyzed separately. Based on the results, calculations are made taking into account the actual (absolute) level of costs for the past period and analysis various possibilities allowing the realization of identified reserves to reduce losses. That is, the standards are not static, but are regularly revised.

The absolute level of costs in this case means the balance between the transferred electricity and technical (relative) losses. Technological loss standards are determined by appropriate calculations.

Who pays for lost electricity?

It all depends on the defining criteria. If we are talking about technological factors and costs of supporting the operation of related equipment, then payment for losses is included in the tariffs for consumers.

The situation is completely different with the commercial component; if the established loss rate is exceeded, the entire economic load is considered an expense for the company that supplies electricity to consumers.

Ways to reduce losses in electrical networks

Costs can be reduced by optimizing the technical and commercial components. In the first case, the following measures should be taken:

• Optimization of the circuit and operating mode of the electrical network.
• Study of static stability and identification of powerful load nodes.
• Decline total power due to the reactive component. As a result, the share of active power will increase, which will have a positive impact on the fight against losses.
• Transformer load optimization.
• Equipment modernization.
• Various load balancing methods. For example, this can be done by introducing a multi-tariff payment system, in which during peak load hours the cost of kW/h is increased. This will significantly reduce the consumption of electricity during certain periods of the day; as a result, the actual voltage will not “sag” below acceptable standards.

You can reduce your business costs by:

• regular search for unauthorized connections;
• creation or expansion of units exercising control;
• checking readings;
• automation of data collection and processing.

Methodology and example for calculating electricity losses

In practice, the following methods are used to determine losses:

• carrying out operational calculations;
• daily criterion;
• calculation of average loads;
• analysis of the greatest losses of transmitted power by day and hour;
• access to generalized data.

Full information on each of the methods presented above can be found in regulatory documents.

In conclusion, we give an example of calculating costs in a TM 630-6-0.4 power transformer. The calculation formula and its description are given below; it is suitable for most types of similar devices.

To understand the process, you should familiarize yourself with the main characteristics of TM 630-6-0.4.

Now let's move on to the calculation.

When transmitting electrical energy, losses occur in each element of the electrical network. To study the components of losses in various network elements 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 are defined as the difference in electricity supplied to the electrical network and usefully supplied to consumers. These losses include components of various natures: losses in network elements that are purely physical in nature, electricity consumption for the operation of equipment installed at substations and ensuring the transmission of electricity, errors in recording electricity by metering devices and, finally, theft of electricity, non-payment or incomplete payment meter readings, etc.

Actual losses can be divided into four components:

– technical losses of electricity, which occur during the transmission of electricity through electrical networks, caused by physical processes in wires, cables and electrical equipment;

– the amount of electricity spent on the substations’ own needs necessary to ensure operation technological equipment substations and the life activity of maintenance personnel, determined by the readings of meters installed on the TSN;

– electricity losses caused by errors in their measurement (instrumental losses) ;

– commercial losses, caused by theft of electricity, interference in the connection diagram, impact on metering devices with a magnet, discrepancy between meter readings and payments for electricity by household consumers and other reasons in the area of ​​organizing control over energy consumption. Their value is determined as the difference between actual (reported) losses and the sum of the first three components:

The first three components of the loss structure are determined by the technological needs of the process of transmitting electricity through networks and instrumental accounting of its receipt and supply. The sum of these components is well described by the term technological losses. The fourth component - commercial losses - represents the impact of the “human factor” and includes all its manifestations: deliberate theft of electricity by some subscribers by changing meter readings, non-payment or incomplete payment of meter readings, etc.

The criteria for classifying a portion of electricity as losses can be of a physical or economic nature.

The sum of technical losses, electricity consumption for the own needs of substations and commercial losses can be called physical losses of electricity. These components are really related to the physics of energy distribution throughout the network. In this case, the first two components of physical losses relate to the technology of transmitting electricity through networks, and the third - to the technology of controlling the amount of transmitted electricity.

Economics defines losses as the difference between supply to the network and useful supply to consumers. It should be noted that useful supply is not only that part of the electricity that was paid, but also that for which the energy sales company was invoiced. If the subscriber's consumption was not recorded in the current billing period (bypass, payment, AIP, etc.), then the accrual will be made based on average monthly consumption.

From an economic point of view, the consumption of electricity for the own needs of substations is no different from the consumption in network elements for transmitting the rest of the electricity to consumers.

Underestimation of the volumes of usefully supplied electricity is the same economic loss as the two components described above. The same can be said about electricity theft. Thus, all four components of losses described above are the same from an economic point of view.

Technical losses of electricity can be represented by the following structural components:

– losses idle move, including losses in electricity in power transformers, compensating devices (CDs), voltage transformers, meters and HF communication connection devices, as well as losses in insulation of cable lines;

– load losses in substation equipment. These include losses in lines and power transformers, as well as losses in electrical energy measuring systems,

– climatic losses, including two types of losses: losses due to corona and losses due to leakage currents in the insulators of overhead lines and substations. Both types depend on weather conditions.

Technical losses in electrical networks of energy supply organizations (power systems) must be calculated over three voltage ranges:

– in supply networks of voltage 35 kV and higher;

– in medium voltage distribution networks 6 - 10 kV;

– in low voltage distribution networks 0.38 kV.

Distribution networks 0.38 - 6 - 10 kV, operated by the electrical network district (RES), are characterized by a significant share of electricity losses. This is due to the peculiarities of the length, construction, operation, and organization of operation of this type of network: big amount elements, branching of circuits, insufficient provision of metering devices of the appropriate class, etc.

Currently, for each distribution zone of power systems, technical losses in networks of 0.38 - 6 - 10 kV are calculated monthly and summed up for the year. The obtained loss values ​​are used to calculate the planned standard for electricity losses for the next year.

The more electricity losses network companies have, the higher the price of electricity, the constant increase of which places a heavy burden on the consumer.

General information

The structure of actual electricity losses consists of many components. Previously, they were often combined into two large groups: technical and commercial losses. The first included load, conditionally constant losses and electricity consumption for the own needs of substations. All other losses, including instrumental measurement errors, were attributed to the second group of losses. There are certain conventions in this classification. Electricity consumption for own needs is not inherently a “pure” technical loss, and is taken into account by electric meters. Also, metrological errors, unlike other components of commercial losses, have a different origin. Therefore, “commercial losses” were initially interpreted quite broadly; there is even such a definition as “acceptable level of commercial losses” - the value of commercial losses of electricity due to errors in the electricity metering system (electricity meters, current and voltage transformers) when the metering system complies with the requirements of the Electrical Electricity Regulations.

Currently, when classifying electricity losses, the term “technological losses of electricity” is more often used, the definition of which is established by Order of the Ministry of Energy of the Russian Federation dated December 30, 2008 No. 326 “On organization in the Ministry of Energy Russian Federation work to approve standards for technological losses of electricity during its transmission through electrical networks.” The collective expression “commercial losses of electricity” is currently not enshrined in legislation, but is found in industry regulatory and technical documents. In one of them, commercial losses are understood as the difference between reporting and technical losses, while “technical losses of electricity” are considered to be all “technological consumption of electricity for its transport through electrical networks, determined by calculation.”

Also, in the form of federal statistical observation No. 23-N “Information on the production and distribution of electrical energy”, approved by Order of the Federal State Statistics Service dated October 1, 2012 No. 509, the reporting indicator “commercial losses” is used. Its definition within the framework of Form 23-N sounds like “data on the amount of electricity not paid for by subscribers,” without providing a calculation formula. In industry reporting documents of network companies, for example, in forms 2-reg, 46-EE (transmission), only actual losses are indicated, and in the layouts of 7-energo, a detailed structure of technological losses is indicated. Commercial losses, as well as non-technical or non-technological losses, are not reported on these forms.

In the tables for justification and examination of technological losses of electricity for a regulated period, filled out by network organizations, the mathematical difference between actual and technological losses of electricity is called “non-technical losses of electricity”, although it is more logical to call them “non-technological”.

To avoid confusion in the terminology used, in the aggregated structure of actual electricity losses it is more correct to designate two groups:

1. Technological losses.

2. Commercial losses.

Technological losses include technical losses in electrical networks due to physical processes occurring during the transmission of electricity, electricity consumption for the own needs of substations, and losses due to permissible errors in the electricity metering system.

They are not losses of the enterprise in the fullest sense of the word, since the cost of their standard volume is taken into account in the tariff for electricity transmission. Funds to cover financial costs associated with the purchase of electricity to compensate for technological losses within the established standard are received by the network company as part of the collected revenue for the transmission of electricity.

Technical losses of electricity can be calculated according to the laws of electrical engineering, permissible errors of metering devices - based on their metrological characteristics, and consumption for substations’ own needs can be determined based on the readings of electricity meters.

Commercial losses cannot be measured with instruments and calculated using independent formulas. They are defined mathematically as the difference between actual and technological losses of electricity and are not subject to inclusion in the standard for electricity losses. The costs associated with their payment are not compensated by tariff regulation.

The applied definition of “commercial” (English: “commerce” - “trade”) for this type of loss emphasizes the connection of the loss with the process of turnover of goods, which is electricity. Electricity losses classified as commercial are mostly electricity consumption, which various reasons not documented. Therefore, it is not taken into account as a return from the networks, and is not presented to any consumers for payment.

In accordance with current legislation, network organizations are required to pay for actual losses of electrical energy that occur in their network facilities, and therefore, for commercial losses in their composition. Commercial losses of electricity, unlike technological ones, are a direct financial loss for network companies. Being, on the one hand, the reason for the monetary expenses of the network enterprise, they are at the same time its lost profit from unpaid electricity transmission. Therefore, network organizations, to a greater extent than other participants in the electricity market, are interested in the most accurate accounting of electricity and the correct calculation of its volumes at delivery points at the borders of their balance sheet.

We can talk about the incorrectness of shifting all financial responsibility for commercial losses of electricity to network companies, since the causes of their occurrence, as well as the effectiveness of their identification and elimination, depend not only on the electric network companies. But the fact remains: commercial losses of electricity are a “headache” primarily for network organizations.

At the same time, the imperfection of the legislative and legal framework, the lack of direct contractual relations between network enterprises on energy supply with consumers, insufficient funding and the impossibility of significantly increasing the staff of employees monitoring electricity consumption, limit the ability of network organizations to identify and eliminate the causes of commercial losses of electricity.

Causes of commercial power losses

The amount of commercial electricity losses depends on the values ​​of other structural indicators of the electricity balance. To find out the volume of commercial losses of electricity for a certain period, you must first draw up a balance of electricity for the section of the electrical network in question, determine the actual losses and calculate all the components of technological losses of electricity. Further analysis of electricity losses helps to localize their areas and identify the causes of their occurrence for the subsequent selection of measures to reduce them.

The main causes of commercial electricity losses can be grouped into the following groups:

1. Instrumental, associated with errors in measuring the amount of electricity.

2. Errors in determining the values ​​of electricity supply to the network and useful supply to consumers.

4. Errors in calculating technological losses of electricity.

1. The operation of electricity measuring systems is accompanied by an instrumental error, the magnitude of which depends on the actual technical characteristics of the metering devices and the actual conditions of their operation. The requirements for measuring instruments established by legislative and regulatory technical documents ultimately affect the maximum permissible amount of under-accounting for electricity, which is included in the standard process losses. Deviation of actual under-metering of electricity from the calculated one permissible value refers to commercial losses.

The main reasons leading to the emergence of commercial “instrumental” losses:

Overload of secondary circuits of measuring current transformers (CT) and voltage (VT),

Low power factor (cos φ) of the measured load,

The influence of magnetic and electromagnetic fields of various frequencies on the electricity meter,

Asymmetry and significant voltage drop in secondary measuring circuits,

Deviations from the permissible temperature regime work,

Insufficient sensitivity threshold of electricity meters,

Inflated transformation ratio of measuring CTs,

Systematic errors of induction electricity meters.

Also, the measurement results are influenced by the following factors, the presence of which is largely determined by the existing level of monitoring in the network organization of the condition and correct operation of the fleet of metering devices used:

Excessive service life of measuring systems,

Malfunction of metering devices,

Errors in the installation of metering devices, including incorrect connection diagrams, installation of measuring CTs with different transformation ratios in different phases of the same connection, etc.

There are still outdated induction electricity meters of accuracy class 2.5 that have exhausted their service life. Moreover, such metering devices are found not only among consumers - citizens, but also among consumers - legal entities.

According to the law in force until 2007. GOST 6570-96 “Inductive active and reactive energy meters”, the service life of electricity meters with accuracy class 2.5 was limited by the first calibration interval, and from 07/01/97 the production of meters of class 2.5 was discontinued.

Induction meters of accuracy class 2.5 are excluded from the State Register of Measuring Instruments; they are not produced and are not accepted for verification. The verification period for a single-phase induction meter is 16 years, and for a three-phase one – 4 years. Therefore, according to the timing of the verification interval, three-phase induction electricity meters of accuracy class 2.5 should not be used for commercial electricity metering for several years.

The currently valid GOST R 52321-2005 (IEC 62053-11:2003) applies to electromechanical (induction) watt-hour meters of accuracy classes 0.5; 1 and 2. For induction electric meters of class 2.5 there are currently no existing regulatory documents, establishing metrological requirements.

It can be concluded that the current use of single-phase induction electricity meters with accuracy class 2.5 as measuring instruments does not comply with the provisions Federal Law dated June 26, 2008 No. 102-FZ "On ensuring the uniformity of measurements."

2. Errors in determining the values ​​of electricity supply to the network and useful supply to consumers are due to the following factors:

Distortions of data on actual readings of electricity meters at any stage of the operational process. This includes errors in visual meter readings, inaccurate data transfer, incorrect entry of information into electronic databases, etc.

Inconsistency of information about the metering devices used, calculated coefficients, and their actual data. Errors can occur already at the stage of concluding a contract, as well as when information is entered inaccurately into electronic databases, their untimely updating, etc. This should also include cases of replacing metering devices without simultaneously drawing up reports and recording the readings taken and installed meter, transformation ratios of instrument transformers.

Unsettled contractual terms in the field of electricity supply and the provision of electricity transmission services in relation to the composition of delivery points, metering devices and the applied algorithms for calculating losses in electrical equipment when they are installed not at the border of the balance sheet. Such situations can lead not only to errors in calculations, especially when changing the owner of a facility, restructuring of organizations that consume electricity, etc., but also to the actual “non-contractual” power supply of facilities in the absence of official inclusion of specific delivery points in energy supply or service contracts for electricity transmission.

Lack of simultaneity in taking readings from electricity meters, both at consumers and at points of electricity supply to the network (return from the network).

Inconsistency between the calendar periods for identifying and including unaccounted for electricity in the volume of its transmission.

Installation of metering devices not on the balance sheet boundary of the networks, inaccuracies and errors in the applied algorithms for calculating electrical energy losses in network elements from the balance sheet border to the measurement point, or the absence of such algorithms for “additional calculation” of electricity losses.

Determination of the amount of transmitted electricity by calculation methods in the absence of metering devices or its malfunction.

- “Unmetered” power supply, with determination of the amount of electricity consumed by the installed capacity of electrical receivers, as well as with the use of other regulatory and calculation methods. Such cases violate the provisions of Federal Law No. 261 - Federal Law "On energy saving and increasing energy efficiency and on introducing amendments to certain legislative acts of the Russian Federation" dated November 23, 2009, regarding the installation of electrical energy metering devices and their commissioning.

Insufficient equipment of electrical energy metering devices at the boundaries of the balance sheet of electrical networks, incl. with multi-apartment residential buildings.

The presence of ownerless networks, the lack of work to identify their balance holders.

Application of replacement (calculated) information during the period of under-metering of electricity in the event of a malfunction of the meter.

3. Unauthorized power consumption.

This category includes the so-called “theft” of electricity, which includes unauthorized connection to electrical networks, connection of electrical receivers in addition to the electric meter, as well as any interference with the operation of metering devices and other actions with the aim of understating the electricity meter readings. This should also include untimely notification to the energy supply organization about malfunctions of metering devices.

Unauthorized electricity consumption often accounts for the bulk of commercial losses, especially in the 0.4 kV network. Most household consumers, especially in the private residential sector, engage in all kinds of electricity theft, but there are cases of electricity theft by industrial and commercial enterprises, mostly small ones.

The volume of electricity theft increases during periods low temperature air, which indicates that the bulk of the unaccounted electricity during this period is spent on heating.

4. Errors in calculations of technological losses of electricity:

Since commercial losses are a calculated value obtained mathematically, errors in determining technological energy consumption have a direct impact on the value of commercial losses. Errors in calculations of technological losses are determined by the calculation methodology used, completeness and reliability of information. The accuracy of calculations of load losses of electricity carried out using methods of operational calculations or calculation days is undoubtedly higher than when calculating using the method of average loads or generalized network parameters. In addition, the actual technical parameters of the electrical network elements often have deviations from the reference and passport values ​​used in the calculations, which is associated with the duration of their operation and the actual technical condition of the electrical equipment. Parameter Information electrical modes network operation, electricity consumption for own needs, also does not have ideal reliability, but contains a certain amount of error. All this determines the total error in calculations of technological losses. The higher their accuracy, the more accurate the calculation of commercial electricity losses will be.

Ways to reduce commercial losses

Measures aimed at reducing commercial electricity losses are determined by the reasons for their occurrence. Many measures to reduce commercial electricity losses are covered in sufficient detail in the scientific and technical literature. The main list of measures aimed at improving electricity metering devices is given in the industry instructions.

Measures to reduce commercial electricity losses can be divided into two groups:

1. Organizational, increasing the accuracy of calculations of electricity balance indicators, incl. useful holiday to consumers.

2. Technical, mainly related to the maintenance and improvement of electricity metering systems.

The main organizational activities include the following:

- Checking the availability of acts of delineation of balance sheet ownership by points of supply of external and internal sections of electricity metering, timely recording of all points of supply of electricity, checking for compliance with contractual terms.

- Formation and timely updating of databases on electricity consumers and metering groups, linking them to specific elements of the electrical network diagram.

- Reconciliation of actual technical characteristics of metering devices and those used in calculations.

- Checking the presence and correctness of algorithms for “additional calculation” of losses when installing metering devices not on the balance sheet boundary.

- Timely reconciliation of meter readings, maximum automation of operational activities for calculating electricity volumes to eliminate the influence of the “human factor”.

- Elimination of the practice of “unmetered” electricity supply.

- Carrying out calculations of technological losses of electricity, increasing the accuracy of their calculations.

- Monitoring actual imbalances of electricity at substations, timely taking measures to eliminate excess deviations.

- Calculations of “feeder” balances of electricity in the network, balances for 10(6)/0.4 kV transformer substations, in 0.4 kV lines, to identify “hot spots” of commercial electricity losses.

- Detection of electricity theft.

- Providing personnel performing checks of metering devices and identifying electricity thefts with the necessary tools and equipment. Training in methods of detecting electricity theft, increasing motivation with additional material rewards taking into account work efficiency.

The main technical measures aimed at reducing commercial electricity losses include the following:

- Inventory of electric power measuring systems, marking them with visual control signs, sealing of electric meters, measuring transformers, installation and sealing of protective covers of terminal clamps of measuring circuits.

- Timely instrumental testing of metering devices, their verification and calibration.

- Replacement of electricity meters and instrument transformers with metering devices with increased accuracy classes.

- Elimination of underload and overload of current and voltage transformers, unacceptable level of voltage losses in VT measuring circuits.

- Installation of metering devices at the boundaries of the balance sheet, incl. electricity metering points at the boundary of the balance sheet section passing along power lines.

- Improving the calculation and technical accounting of electricity, replacing outdated measuring instruments, as well as metering devices with technical parameters that do not comply with legislative and regulatory-technical requirements.

- Installation of metering devices outside private property.

- Replacement of “naked” aluminum wires Overhead lines - 0.4 kV on self-supporting insulated wires, replacement of inputs into buildings made with bare wire with coaxial cables.

- Implementation of automated information and measurement systems for commercial electricity metering (AIIS KUE), both for industrial and household consumers.

The last of these measures is the most effective in reducing commercial electricity losses, since it is comprehensive solution main key tasks, ensuring reliable and remote receipt of information from each measurement point, carrying out constant monitoring of the serviceability of metering devices. In addition, the implementation of unauthorized power consumption is made as difficult as possible, and the identification of “hot spots” of losses in as soon as possible with minimal labor costs. The limiting factor for widespread automation of electricity metering is the high cost of AIMS KUE systems. The implementation of this activity can be carried out in stages, identifying priority nodes of the electrical network for metering automation based on a preliminary energy survey with an assessment of the economic efficiency of the project implementation.

To address issues of reducing commercial electricity losses, it is also necessary to improve the regulatory framework in the field of energy supply and electricity metering. In particular, the application of consumption standards utilities on electricity supply should encourage subscribers to install metering devices as quickly as possible (eliminate their malfunctions), and not to calculate the benefits of their absence. The procedure for admitting representatives of network companies to check the condition of metering devices and take their readings from consumers, primarily individuals, should be as simple as possible, and liability for unauthorized power consumption should be increased.

Conclusion

Commercial losses of electricity are a serious financial loss for network enterprises and divert their funds from solving other pressing problems in the field of electricity supply.

Reducing commercial electricity losses is a complex task, which in its solution requires the development of specific measures based on a preliminary energy survey and determination of the actual structure of electricity losses and their causes.

ANO "Energy Saving Agency UR" carries out all work related to energy inspection of enterprises, monitoring of electricity consumption, calculation and standardization of technological losses of electricity, determination of the structure of electricity losses and development of measures to reduce them.

LITERATURE:

1. RD 34.09.254 “Instructions for reducing the technological consumption of electrical energy for transmission through electrical networks of power systems and energy associations. And 34-70-028-86”, M., SPO Soyuztekhenergo, 1987

2. RD 153-34.0-09.166-00 “Standard program for conducting energy surveys of electrical network divisions of JSC-Energo”, SPO ORGRES, 2000

3. Order of the Ministry of Energy of the Russian Federation dated December 30, 2008 No. 326 “On the organization in the Ministry of Energy of the Russian Federation of work to approve standards for technological losses of electricity during its transmission through electrical networks”

4. Rules for non-discriminatory access to services for the transmission of electrical energy and the provision of these services (approved by Decree of the Government of the Russian Federation of December 27, 2004 No. 861)

5. Vorotnitsky V.E., Kalinkina M.A. Calculation, regulation and reduction of electricity losses in electrical networks (Training and methodological manual) - M.: IUE GUU, VIPKenergo, IPKgossluzhby, 2003

6. Vorotnitsky V.E., Zaslonov S.V., Kalinkina M.A., Parinov I.A., Turkina O.V. Methods and tools for calculating, analyzing and reducing losses of electrical energy during its transmission through electrical networks M.: DialogueElectro, 2006

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Methodology for calculating technological losses of electricity
in the power line VL-04kV of the gardening partnership

Until a certain time, the need to calculate technological losses in power lines, owned by SNT, as legal entity, or gardeners who have garden plots within the boundaries of any SNT, was not needed. The board didn't even think about it. However, meticulous gardeners, or rather doubters, forced us to once again throw all our efforts into ways to calculate electricity losses in Power lines

. The easiest way, of course, is to stupidly contact a competent company, that is, an electricity supply company or a small firm, which will be able to calculate the technological losses in their network for gardeners. Scanning the Internet made it possible to find several methods for calculating energy losses in an internal power line in relation to any SNT. Their analysis and analysis of the necessary values ​​for calculating the final result made it possible to discard those of them that involved measuring special parameters in the network using special equipment. along the lines of a basic school physics course. When creating it, the standards of the order of the Ministry of Industry and Energy of the Russian Federation No. 21 of 02/03/2005 “Methodology for calculating standard electricity losses in electrical networks” were used, as well as the book by Yu.S. Zhelezko, A.V. Artemyev, O.V. Savchenko “Calculation, analysis and regulation of electricity losses in electrical networks”, Moscow, JSC “Publishing House NTsENAS”, 2008.

The fact is that if the total of gardeners and SNT electrical installations exceeds the amount of electricity allocated to everyone, then accordingly calculation of technological losses must be specified for a different amount of kW/h consumed. The more electricity the SNT consumes, the greater the losses will be. In this case, adjustment of the calculations is necessary to clarify the amount of payment for technological losses in the internal network, and its subsequent approval at the general meeting.

Those. To switchboard SNT, where the common three-phase meter is located, 3 wires (3 phases) and one neutral wire are connected. Accordingly, 20 gardeners’ houses are evenly connected to each phase, for a total of 60 houses.

To calculate losses, the following formula is used:

ΔW = 9.3· W²·(1 + tan²φ)·K f ²·K L.L
D F

ΔW- electricity losses in kW/h;

W- electricity supplied to power line for D (days), kW/h (in our example 63000 kW/h or 63x10 6 W/h);

K f- load curve shape factor;

To L- coefficient taking into account the load distribution along the line ( 0,37 - for a line with a distributed load, i.e.

L 20 gardeners’ houses are connected for each phase of three); 2 - line length in kilometers (in our example

km); tgφ 0,6 );

- reactive power factor ( F

- wire cross-section in mm²; D 365 - period in days (in the formula we use the period

days); K f²

- chart fill factor, calculated by the formula: K f ² =
(1 + 2K z)

3K z Where K z 0,3 - graph filling factor. In the absence of data on the shape of the load curve, the value is usually taken - ;.

Then:

We assume that the total load is evenly distributed along the lines inside the feeder. Those. annual consumption on one feeder line is equal to 1/3 of total consumption.

Then: W sum. = 3 * ΔW in line.

The electricity supplied to gardeners per year is 63,000 kW/h, then for each feeder line: 63000 / 3 = 21000 kW/h or 21 10 6 W/h- it is in this form that the value is present in the formula.

ΔW line =9.3· 21² 10 6 (1+0.6²) 1.78 0.37. 2 =
365 35

Then for a year along three feeder lines: ΔW sum. = 3 x 573.67 = 1721 kW/h.

Losses for the year in The board didn't even think about it. However, meticulous gardeners, or rather doubters, forced us to once again throw all our efforts into ways to calculate electricity losses in in percentages: ΔW sum. % = ΔW sum /W sum x 100% = 2.73%

Provided that all energy consumption metering devices are placed on power transmission line supports, the length of the wire from the connection point of the line belonging to the gardener to his individual metering device will be only 6 meters(total length of support 9 meters).

The resistance of a SIP-16 wire (self-supporting insulated wire, cross-section 16 mm²) per 6 meters of length is only R = 0.02ohm.

P input = 4 kW(let’s take it as the calculated permitted electrical power for one house).

We calculate the current strength for a power of 4 kW: I input = P input /220 = 4000W / 220V = 18 (A).

Then: dP input = I² x R input = 18² x 0.02 = 6.48W- losses per 1 hour under load.

Then the total losses for the year in the line of one connected gardener: dW input = dP input x D (hours per year) x K use.max..

load = 6.48 x 8760 x 0.3 = 17029 Wh (17.029 kWh)
Then the total losses in the lines of 60 connected gardeners per year will be:

Accounting for total losses in power lines for the year:

ΔW sum. total = 1721 + 1021.24 = 2745.24 kW/h

ΔW sum. %= ΔW sum / W sum x 100%= 2745.24/63000 x 100%= 4.36% Total:

In an internal overhead power line SNT with a length of 2 kilometers (3 phases and zero), a wire with a cross-section of 35 mm², connected by 60 houses, with a total consumption of 63,000 kW/h of electricity per year, the losses will be 4.36%

• Important Notes:
• When calculating losses on a section of a line owned by a gardener, the resistance coefficient (0.02 ohms) of one SIP-2x16 wire at 20°C with a length of 6 meters was taken into account. Accordingly, if your SNT meters do not hang on supports, then it is necessary to increase the resistance coefficient in proportion to the length of the wire.
• When calculating losses on a section of a line owned by a gardener, you should also take into account the permitted power for the house. With different consumption and permitted power, the losses will be different. It would be correct and appropriate to distribute power depending on needs:
  for a gardener-dacha resident - 3.5 kW (i.e. corresponds to the limitation on the 16A residual current circuit breaker);
  for a gardener permanently residing in SNT - from 5.5 kW to 7 kW (respectively, overload circuit breakers for 25A and 32A).
• When obtaining data on losses for residents and summer residents, it is advisable to establish different payments for technological losses for these categories of gardeners (see point 3 of the calculation, i.e., depending on the value I- current strength, for a summer resident at 16A, the losses will be less than for a permanent resident at 32A, which means there should be two separate calculations of losses at the entrance to the house).

Example: In conclusion, it should be added that our SNT "Pishchevik" ESO "Yantarenergo" at the conclusion of the Electricity Supply Agreement in 1997 established the value calculated by them technological losses from the transformer substation to the installation site of the general electricity meter equal to 4.95% per 1 kW/h. The calculation of line losses using this method was 1.5% maximum. It’s hard to believe that the losses in the transformer, which SNT does not belong to, still amount to almost 3.5%. And according to the Agreement, the losses of the transformer are not ours. It's time to sort this out.
You will soon learn about the result. Let's continue. Previously, our accountant at SNT charged 5% per kWh for losses established by Yantarenergo and 5% for losses within SNT. Naturally, no one expected anything. The calculation example used on the page corresponds almost 90% to reality when operating an old power line in our SNT. So this money was enough to pay for all the losses in the network. Even surpluses remained and gradually accumulated. This emphasizes the fact that the technique works and is fully consistent with reality. Compare for yourself: 5% and 5% (there is a gradual accumulation of surplus) or 4.95% and 4.36% (no surplus). Those., calculation of electricity losses

Electricity losses in electrical networks are the most important indicator of the efficiency of their operation, a clear indicator of the state of the electricity metering system, and the efficiency of energy sales activities of energy supply organizations. This indicator increasingly clearly indicates accumulating problems that require urgent solutions in the development, reconstruction and technical re-equipment of electrical networks, improvement of methods and means of their operation and management, increasing the accuracy of electricity metering, the efficiency of collecting funds for electricity supplied to consumers, etc. . According to international experts, the relative losses of electricity during its transmission and distribution in the electrical networks of most countries can be considered satisfactory if they do not exceed 4-5%. Electricity losses of 10% can be considered the maximum permissible from the point of view of the physics of electricity transmission through networks. It is becoming increasingly obvious that the sharp aggravation of the problem of reducing electricity losses in electrical 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 a sharp reduction in investments in the development and technical re-equipment of electrical networks, in the improvement of control systems for their modes, electricity metering, a number of negative trends have emerged that negatively affect the level of losses in networks, such as: outdated equipment, physical and moral wear and tear of electricity metering devices , mismatch of installed equipment with transmitted power.
From the above it follows that against the backdrop of ongoing changes in the economic mechanism in the energy sector and the economic crisis in the country, the problem of reducing electricity losses in electrical networks not only has not lost its relevance, but, on the contrary, has become one of the tasks of ensuring the financial stability of energy supply organizations.

Some definitions:
Absolute losses of electricity are the difference in 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 losses of electricity are losses defined as the difference between absolute and technical losses.

STRUCTURE OF COMMERCIAL ELECTRICITY LOSSES

Errors in measurements of electricity supplied to the network and usefully supplied to consumers.
The error in electricity measurements in the general case can be divided into many components. Let us consider the most significant components of the errors of measuring complexes (MC), which may include: current transformer (CT), voltage transformer (VT), electricity meter (EM), ESS connection line to TN.

The main components of measurement errors of electricity supplied to the network and usefully supplied electricity include:
errors in electricity measurements under normal conditions
IR work, determined by the accuracy classes of CT, VT and SE;
additional errors in electricity measurements in real operating conditions of the IR, due to:
underestimated load power factor compared to the standard (additional angular error); .
influence on solar cells of magnetic and electromagnetic fields of various frequencies;
underload and overload of CTs, HP and SE;
asymmetry and level of voltage supplied to the IR;
operation of solar power in unheated rooms with unacceptably low temperatures, etc.;
insufficient sensitivity of solar cells at low loads, especially at night;
systematic errors caused by excess service life of the IC.
errors associated with incorrect connection diagrams of electricity meters, CTs and VTs, in particular, phasing violations of meter connections;
errors caused by faulty electricity metering devices;
errors in reading electricity meters due to:
errors or intentional distortions in recordings of testimony;
non-simultaneity or failure to meet 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 useful supply, commercial losses will decrease, and if they are different, they will increase. This means that from the point of view of reducing commercial losses of electricity, it is necessary to pursue a coordinated technical policy to increase the accuracy of measurements of supply to the network and useful 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, occurs in practice.
Commercial losses caused by underestimation of useful supply due to shortcomings in energy sales activities.
These losses include two components: billing losses and losses from electricity theft.

Billing losses.

This commercial component is due to:
inaccuracy of data on electricity consumers, including insufficient or erroneous information on 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 to customers using special rates;
lack of control and accounting of adjusted accounts, etc.

Losses from electricity theft.

Theft of electricity has a fairly clear upward trend, especially in regions with poor heat supply to consumers during the cold periods of the year. L also in almost all regions in 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 methods of electricity theft: mechanical, electrical, magnetic.
Mechanical methods of electricity theft.

Mechanical methods of electricity theft.

Electrical methods of electricity theft.

If meters are connected via measuring transformers, the following can also be used:
disconnection of CT current circuits;
replacing normal VT fuses with blown ones, etc.

Magnetic methods of energy theft.

Commercial losses of electricity due to the presence of ownerless consumers.

Commercial losses caused by non-simultaneity of payments for electricity by household consumers - the so-called “seasonal component”.
This very significant component of commercial electricity losses occurs due to the fact that residential consumers are objectively unable to simultaneously take meter readings and pay for electricity. As a rule, payments lag behind actual electricity consumption, which, of course, introduces an error in determining the actual useful supply household consumer and into the calculation of 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 annual electricity losses rarely had a commercial component. Currently, autumn-winter and winter-spring seasonal underpayments for electricity far exceed in most cases the total payment in other periods of the year. Therefore, commercial losses occur by month, quarter and for the year as a whole.

Errors in calculating technical losses of electricity in electrical networks.