Siemens is a recognized world leader in the development of energy systems, including heat and water supply systems. This is exactly what one of the Departments does Siemens - Building Technologies – “Automation and safety of buildings.” The company offers a full range of equipment and algorithms for the automation of boiler houses, heating points and pumping stations.

1. Structure of the heat supply system

Siemens offers comprehensive solution to create unified system management of urban heat and water supply systems. The complexity of the approach lies in the fact that customers are offered everything from performing hydraulic calculations of heat and water supply systems to communication and dispatch systems. The implementation of this approach is ensured by the accumulated experience of the company’s specialists, acquired in different countries of the world during the implementation of various projects in the field of heat supply systems in large cities of Central and Eastern Europe. This article discusses the structures of heat supply systems, principles and control algorithms that were implemented during the implementation of these projects.

Heat supply systems are built primarily according to a 3-stage scheme, the parts of which are:

1. Heat sources of different types, interconnected into a single loop system

2. Central heating points(central heating stations) connected to main heating networks with high temperature coolant (130...150°C). In the central heating substation, the temperature gradually decreases to a maximum temperature of 110 °C, based on the needs of the heating substation. In small systems, the level of central heating points may be absent.

3. Individual heating points receiving thermal energy from central heating stations and providing heat supply to the facility.

The fundamental feature of Siemens solutions is that the entire system is based on the principle of 2-pipe wiring, which is the best technical and economic compromise. This solution makes it possible to reduce heat losses and electricity consumption in comparison with the 4-pipe or 1-pipe systems with open water intake that are widespread in Russia, investments in the modernization of which without changing their structure are not effective. The costs of maintaining such systems are constantly increasing. Meanwhile, exactly economic effect is the main criterion for the feasibility of development and technical improvement of the system. It is obvious that when constructing new systems, optimal solutions tested in practice should be taken. If we are talking about major renovation heat supply systems of a non-optimal structure, it is economically profitable to switch to a 2-pipe system with individual heating points in each house.

When providing consumers with heat and hot water, the management company incurs fixed costs, the structure of which is as follows:

Costs of generating heat for consumption;

losses in heat sources due to imperfect heat generation methods;

heat losses in heating mains;

r electricity costs.

Each of these components can be reduced by optimal control and the use of modern automation tools at every level.

2. Heat sources

It is known that for heating systems, large sources of combined heat and power generation or sources in which heat is a secondary product, for example, a product of industrial processes, are preferable. It was on the basis of such principles that the idea of ​​central heating arose. Boiler houses operating on different types of fuel are used as backup heat sources. gas turbines and so on. If gas boiler houses serve as the main source of heat, they must operate with automatic optimization of the combustion process. This is the only way to achieve savings and reduce emissions compared to distributed heat generation in each house.

3. Pumping stations

Heat from heat sources is transferred to main heating networks. The coolant is pumped by network pumps that operate continuously. Therefore, special attention should be paid to the selection and method of operating pumps. The operating mode of the pump depends on the modes of the heating points. A decrease in flow at the central heating station entails an undesirable increase in the pressure of the pump (pumps). An increase in pressure negatively affects all components of the system. At best, only hydraulic noise increases. In any case, electrical energy is lost. Under these conditions, an unconditional economic effect is ensured by frequency control of pumps. Various control algorithms are used. In the basic design, the controller maintains a constant pressure drop across the pump by varying the rotation speed. Due to the fact that with a decrease in coolant flow, pressure losses in the lines are reduced (quadratic dependence), it is also possible to reduce the set value (set) of the pressure drop. This type of pump control is called proportional and can further reduce pump operating costs. More efficient control of pumps with task correction based on a “remote point”. In this case, the pressure drop at the end points of the main networks is measured. The current differential pressure values ​​compensate for the pressure at the pumping station.

4. Central heating points (CHS)

IN modern systems Heat supply to central heating stations plays a very important role. An energy-saving heat supply system should operate using individual heating points. However, this does not mean that central heating stations will be closed: they perform the function of a hydraulic stabilizer and at the same time divide the heat supply system into separate subsystems. In the case of using ITP, central hot water supply systems are excluded from the central heating point. In this case, only 2 pipes pass through the central heating substation, separated by a heat exchanger, which separates the system of main routes from the ITP system. Thus, the ITP system can operate with other coolant temperatures, as well as with lower dynamic pressures. This guarantees stable work ITP and at the same time entails a reduction in investment in ITP. The supply temperature from the central heating point is adjusted in accordance with the temperature schedule based on the outside air temperature, taking into account the summer limit, which depends on the demand of the domestic hot water system in the heating and heating system. We are talking about preliminary adjustment of coolant parameters, which allows reducing heat losses in secondary routes, as well as increasing the service life of thermal automation components in ITP.

5. Individual heating points (IHP)

The operation of the IHP affects the efficiency of the entire heat supply system. ITP is a strategically important part of the heat supply system. The transition from a 4-pipe system to a modern 2-pipe system is not without its challenges. Firstly, this entails the need for investment, and secondly, without the presence of a certain “know-how”, the introduction of ITP can, on the contrary, increase operating costs management company. The principle of operation of the ITP is that the heating point is located directly in the building, which is heated and for which hot water is prepared. At the same time, only 3 pipes are connected to the building: 2 for coolant and 1 for cold water supply. Thus, the structure of the system pipelines is simplified, and during planned repairs of routes, savings on pipe laying immediately occur.

5.1. Heating circuit control

The ITP controller controls the thermal power of the heating system, changing the temperature of the coolant. The heating temperature setpoint is determined from the outside temperature and the heating curve (weather-compensated control). The heating curve is determined taking into account the inertia of the building.

5.2. Inertia of the building

The inertia of buildings has a significant influence on the outcome of weather-compensated heating control. A modern ITP controller must take this influencing factor into account. The inertia of a building is determined by the value of the building's time constant, which ranges from 10 hours for panel houses to 35 hours for brick houses. The IHP controller determines, based on the building time constant, the so-called “combined” outdoor air temperature, which is used as a correction signal in the automatic heating water temperature control system.

5.3. Wind power

Wind significantly affects the room temperature, especially in high-rise buildings located in open areas. An algorithm for correcting water temperature for heating, taking into account the influence of wind, provides up to 10% savings in thermal energy.

5.4 Return water temperature limitation

All types of control described above indirectly affect the reduction of return water temperature. This temperature is the main indicator of the economical operation of the heating system. Under various operating modes of the IHP, the return water temperature can be reduced using limiting functions. However, all restriction functions entail deviations from comfortable conditions, and their use must have a feasibility study. In independent heating circuit connection schemes, with economical operation of the heat exchanger, the temperature difference between the return water of the primary circuit and the heating circuit should not exceed 5°C. Cost-effectiveness is ensured by the function of dynamic limitation of return water temperature ( DRT – differential of return temperature ): when the specified temperature difference between the return water of the primary circuit and the heating circuit is exceeded, the controller reduces the coolant flow in the primary circuit. At the same time, the peak load also decreases (Fig. 1).

Features of heat supply are the strict mutual influence of heat supply and heat consumption modes, as well as the multiplicity of delivery points for several goods (thermal energy, power, coolant, hot water). The purpose of heat supply is not to ensure generation and transport, but to maintain the quality of these goods for each consumer.

This goal was achieved relatively effectively with stable coolant flows in all elements of the system. The “quality” regulation we use by its very essence implies a change only in the temperature of the coolant. The emergence of buildings with controlled consumption has ensured unpredictability of hydraulic regimes in networks while maintaining constant costs in the buildings themselves. Complaints in neighboring houses had to be eliminated by increased circulation and corresponding massive overheating.

Hydraulic calculation models used today, despite their periodic calibration, cannot account for deviations in flow rates at building inputs due to changes in internal heat generation and consumption hot water, as well as the influence of sun, wind and rain. With actual qualitative and quantitative regulation, it is necessary to “see” the system in real time and ensure:

• control of the maximum number of delivery points;
• compilation of current balances of supply, losses and consumption;
• control action in case of unacceptable violation of regimes.

Management must be as automated as possible, otherwise it is simply impossible to implement. The challenge was to achieve this without incurring excessive control point equipment costs.

Today, when a large number of buildings have measuring systems with flow meters, temperature and pressure sensors, use them only for financial settlements unreasonable. ACS “Teplo” is built mainly on the generalization and analysis of information “from the consumer”.

When creating the automated control system, typical problems of outdated systems were overcome:

• dependence on the correctness of calculations of metering devices and the reliability of data in non-verifiable archives;
• impossibility of compiling operational balances due to inconsistencies in measurement times;
• inability to control rapidly changing processes;
• non-compliance with the new information security requirements of the federal law “On the security of critical information infrastructure Russian Federation».

Effects of implementing the system:

Consumer Services:

• determination of real balances for all types of goods and commercial losses:
• determination of possible off-balance sheet income;
• control of actual power consumption and compliance with its specifications for connection;
• introduction of restrictions corresponding to the level of payments;
• transition to a two-part tariff;
• monitoring KPIs for all services working with consumers and assessing the quality of their work.

Operation:

• determination of technological losses and balances in heating networks;
• dispatch and emergency control according to actual conditions;
• maintaining optimal temperature schedules;
• monitoring the status of networks;
• adjustment of heat supply modes;
• control of shutdowns and regime violations.

Development and investment:

• reliable assessment of the results of implementation of improvement projects;
• assessment of the effects of investment costs;
• development of heat supply schemes in real electronic models;
• optimization of network diameters and configuration;
• reducing connection costs while taking into account real reserves of bandwidth and energy savings among consumers;
• repair planning
• organization collaboration CHP and boiler houses.

1. The distribution of the heat load of thermal energy consumers in the heat supply system between the sources of thermal energy supplying thermal energy in this heat supply system is carried out by the body authorized in accordance with this Federal law for approval of the heat supply scheme by making annual changes to the heat supply scheme.

2. To distribute the heat load of heat energy consumers, all heat supply organizations that own sources of heat energy in a given heat supply system are required to submit to the body authorized in accordance with this Federal Law to approve the heat supply scheme, an application containing information:

1) on the amount of thermal energy that the heat supply organization undertakes to supply to consumers and heat supply organizations in a given heat supply system;

2) on the volume of capacity of thermal energy sources that the heat supply organization undertakes to maintain;

3) on current tariffs in the field of heat supply and forecast specific variable costs for the production of thermal energy, coolant and power maintenance.

3. The heat supply scheme must define the conditions under which it is possible to supply heat energy to consumers from various sources of heat energy while maintaining the reliability of heat supply. If such conditions exist, the distribution of heat load between heat energy sources is carried out on a competitive basis in accordance with the criterion of minimum specific variable expenses for the production of thermal energy by thermal energy sources determined in the manner established by the principles of pricing in the field of heat supply, approved by the Government of the Russian Federation, on the basis of applications from organizations owning sources of thermal energy, and standards taken into account when regulating tariffs in the field of heat supply for the corresponding regulatory period.

4. If the heat supply organization does not agree with the distribution of the heat load carried out in the heat supply scheme, it has the right to appeal the decision on such distribution made by the body authorized in accordance with this Federal Law to approve the heat supply scheme to the federal executive body authorized by the Government of the Russian Federation.

5. Heat supply organizations and heating network organizations operating in the same heat supply system are required annually before the start of the heating season to enter into an agreement with each other on the management of the heat supply system in accordance with the rules for organizing heat supply approved by the Government of the Russian Federation.

6. The subject of the agreement specified in Part 5 of this article is the procedure for mutual actions to ensure the functioning of the heat supply system in accordance with the requirements of this Federal Law. Required terms of the said agreement are:

1) determination of the subordination of dispatch services of heat supply organizations and heating network organizations, the procedure for their interaction;

2) the procedure for organizing the adjustment of heating networks and regulating the operation of the heat supply system;

3) the procedure for ensuring access of the parties to the agreement or, by mutual agreement of the parties to the agreement, another organization to heat networks for setting up heat networks and regulating the operation of the heat supply system;

4) the procedure for interaction between heat supply organizations and heating network organizations in emergency situations and emergency situations.

7. If heat supply organizations and heating network organizations have not concluded the agreement specified in this article, the procedure for managing the heat supply system is determined by the agreement concluded for the previous heating period, and if such an agreement was not concluded earlier, the specified procedure is established by the body authorized in accordance with this Federal law for approval of the heat supply scheme.

Article 18. Distribution of heat load and management of heat supply systems

1. The distribution of the heat load of thermal energy consumers in the heat supply system between those supplying thermal energy in this heat supply system is carried out by the body authorized in accordance with this Federal Law to approve the heat supply scheme by making annual changes to the heat supply scheme.

2. To distribute the heat load of heat energy consumers, all heat supply organizations that own sources of heat energy in a given heat supply system are required to submit to the body authorized in accordance with this Federal Law to approve the heat supply scheme, an application containing information:

1) on the amount of thermal energy that the heat supply organization undertakes to supply to consumers and heat supply organizations in a given heat supply system;

2) on the volume of capacity of thermal energy sources that the heat supply organization undertakes to maintain;

3) on current tariffs in the field of heat supply and forecast specific variable costs for the production of thermal energy, coolant and power maintenance.

3. The heat supply scheme must define the conditions under which it is possible to supply thermal energy to consumers from various sources of thermal energy while maintaining the reliability of heat supply. If such conditions exist, the distribution of heat load between heat energy sources is carried out on a competitive basis in accordance with the criterion of minimum specific variable costs for the production of heat energy by heat energy sources, determined in the manner established by the pricing framework in the field of heat supply, approved by the Government of the Russian Federation, on the basis of applications organizations owning sources of thermal energy, and standards taken into account when regulating tariffs in the field of heat supply for the corresponding period of regulation.

4. If the heat supply organization does not agree with the distribution of the heat load carried out in the heat supply scheme, it has the right to appeal the decision on such distribution made by the body authorized in accordance with this Federal Law to approve the heat supply scheme to the federal executive body authorized by the Government of the Russian Federation.

5. Heat supply organizations and heating network organizations operating in the same heat supply system are required annually before the start of the heating season to enter into an agreement with each other on the management of the heat supply system in accordance with the rules for organizing heat supply approved by the Government of the Russian Federation.

6. The subject of the agreement specified in Part 5 of this article is the procedure for mutual actions to ensure the functioning of the heat supply system in accordance with the requirements of this Federal Law. The mandatory terms of this agreement are:

1) determination of the subordination of dispatch services of heat supply organizations and heating network organizations, the procedure for their interaction;

3) the procedure for ensuring access of the parties to the agreement or, by mutual agreement of the parties to the agreement, another organization to heat networks for setting up heat networks and regulating the operation of the heat supply system;

4) the procedure for interaction between heat supply organizations and heating network organizations in emergencies and emergencies.

7. If heat supply organizations and heating network organizations have not concluded the agreement specified in this article, the procedure for managing the heat supply system is determined by the agreement concluded for the previous heating period, and if such an agreement was not concluded earlier, the specified procedure is established by the body authorized in accordance with this Federal law for approval of the heat supply scheme.

Modernization and Automation of Heat Supply System Minsk experience

V.A. Sednin, Scientific Consultant, Doctor of Engineering, Professor,
A.A. Gutkovskiy, Chief Engineer, Belarusian National Technical University, Scientific Research and Innovations Center of Automated Control Systems in heat power industry

Keywords: heat supply system, automated control systems, reliability and quality improvement, heat delivery regulation, data archiving

Heat supply of large cities in Belarus, as in Russia, is provided by cogeneration and district heat supply systems (hereinafter - DHSS), where facilities are combined into a single system. However, often the decisions made on individual elements of complex heat supply systems do not meet the systematic criteria, reliability, controllability and environmental protection requirements. Therefore modernization of the heat supply systems and creation of automated process control systems is the most relevant task.

Description:

V. A. Sednin, A. A. Gutkovsky

Heat supply to large cities in Belarus, as in Russia, is provided by heating and centralized heating systems (hereinafter referred to as DHS), the facilities of which are linked into a single scheme. However, often decisions made on individual elements of complex heat supply systems do not satisfy system criteria, reliability, controllability and environmental friendliness requirements. Therefore, the modernization of heat supply systems and the creation automated systems management technological processes is the most pressing task.

V. A. Sednin, scientific consultant, doctor of technical sciences. sciences, professor

A. A. Gutkovsky, chief engineer, Belarusian National Technical University, Research and Innovation Center for Automated Control Systems in Thermal Power Engineering and Industry

Heat supply to large cities in Belarus, as in Russia, is provided by heating and centralized heating systems (hereinafter referred to as DHS), the facilities of which are linked into a single scheme. However, often decisions made on individual elements of complex heat supply systems do not satisfy system criteria, reliability, controllability and environmental friendliness requirements. Therefore, the modernization of heat supply systems and the creation of automated process control systems is the most urgent task.

Features of district heating systems

Considering the main features of DHS in Belarus, it can be noted that they are characterized by:

• continuity and inertia of its development;
• territorial distribution, hierarchy, variety of technical means used;
• the dynamism of production processes and the stochasticity of energy consumption;
• incompleteness and low degree of reliability of information about the parameters and modes of their operation.

It is important to note that in central heating networks, heating networks, unlike other pipeline systems, serve to transport not a product, but coolant energy, the parameters of which must meet the requirements of various consumer systems.

These features emphasize the essential need to create automated process control systems (hereinafter referred to as automated process control systems), the implementation of which can improve energy and environmental efficiency, reliability and quality of operation of heat supply systems. The introduction of automated process control systems today is not a tribute to fashion, but follows from the basic laws of technology development and is economically justified based on modern stage development of the technosphere.

Development of an automated process control system for the heat supply system in Minsk

Using the example of Minsk, we present the main approaches that were implemented in a number of cities in Belarus and Russia when designing and developing automated process control systems for heat supply systems.

Given the breadth of issues covering subject area heat supply, and the accumulated experience in the field of automation of heat supply systems, a concept was developed at the pre-design stage of creating an automated process control system for Minsk heating networks. The concept defines the fundamental principles of organizing an automated process control system for heat supply in Minsk (see reference) as a process of creating a computer network (system) aimed at automating technological processes of a topologically distributed centralized heat supply enterprise.

Technological information tasks of automated process control systems

The automated control system being introduced primarily aims to improve reliability and quality operational management operating modes of individual elements and the heat supply system as a whole. Therefore, this automated process control system is designed to solve the following technological information problems:

• provision of centralized functional group control of hydraulic modes of heat sources, main heating networks and transfer pumping stations, taking into account daily and seasonal changes in circulation flow rates with adjustments ( feedback) according to actual hydraulic conditions in the city’s heat distribution networks;
• implementation of the method of dynamic central regulation of heat supply with optimization of coolant temperatures in the supply and return pipelines of heating mains;
• ensuring the collection and archiving of data on the thermal and hydraulic operating conditions of heat sources, main heating networks, transfer pumping stations and distribution heat networks of the city for monitoring, operational management and analysis of the functioning of central heating networks of Minsk heating networks;
• Creation effective system protection of equipment of heat sources and heating networks in emergency situations;

Creation information base to solve optimization problems arising during the operation and modernization of objects of the Minsk heat supply system.

Structure of automated process control systems of Minsk heating networks

In accordance with the production and organizational structure of Minsk Heat Networks (see reference 1), a four-level structure of the process control system of Minsk Heat Networks was selected:

• the first (upper) level is the central control room of the enterprise;
• second level – operator stations of district heating networks;
• third level – operator stations of heat sources (operator stations of workshops of heating network sections);
• fourth (lower) level – stations automatic control installations (boiler units) and processes of transport and distribution of thermal energy (technological diagram of the heat source, heating points, heating networks, etc.).

Development (creation of an automated process control system for heat supply to the entire city of Minsk) involves the inclusion into the system at the second structural level of operator stations of the heating complexes of Minsk CHPP-2, CHPP-3, CHPP-4 and the operator station (central control room) of the Minskkommunteploset Unitary Enterprise. All management levels are planned to be combined into a single computer network.

Architecture of the automated process control system for the heat supply system in Minsk

Analysis of the control object as a whole and the state of its individual elements, as well as prospects for the development of the control system, made it possible to propose the architecture of a distributed automated system for controlling technological processes of the heat supply system in Minsk within the facilities of RUE Minskenergo. The corporate network integrates the computing resources of the central office and remote structural units, including automatic control stations (ACS) of objects in network areas. All self-propelled guns (TsTP, ITP, PNS) and scanning stations are connected directly to operator stations of the corresponding network areas, presumably installed in workshop areas.

Remotely structural unit(for example, RTS-6), the following stations are installed (Fig. 1): operator station “RTS-6” (OPS RTS-6) - it is the control center of the network area and is installed at the master site of RTS-6. For operational personnel, OpS RTS-6 provides access to all information and control resources of automatic control systems of all types, without exception, as well as access to authorized information resources central office. OpS RTS-6 provide regular scanning of all slave control stations.

Operational and commercial information collected from all central processing centers is sent for storage to a dedicated database server (installed in close proximity to the RTS-6 ops system).

Thus, taking into account the scale and topology of the control object and the existing organizational and production structure of the enterprise, the process control system of Minsk thermal networks is built according to a multi-link scheme using a hierarchical structure of software and hardware and computer networks that decide various tasks management at every level.

Control system levels

At the lower level, the control system performs:

• preliminary processing and transmission of information;
• regulation of basic technological parameters, control optimization functions, protection of technological equipment.

TO technical means lower level increased reliability requirements are imposed, including the ability to operate autonomously in the event of loss of connection with the upper-level computer network.

Subsequent levels of the control system are built according to the hierarchy of the heat supply system and solve problems at the corresponding level, and also provide an operator interface.

Control devices installed at sites, in addition to their direct responsibilities, must also provide the ability to aggregate them into distributed control systems. The control device must ensure the operability and safety of objective primary accounting information during long communication interruptions.

The main elements of such a scheme are technological and operator stations connected to each other by communication channels. The core of the technological station should be an industrial computer equipped with means of communication with the control object and channel adapters for organizing interprocessor communication. The main purpose of the technological station is the implementation of direct digital control algorithms. In technically justified cases, some functions can be performed in supervisory mode: the process station processor can control remote intelligent controllers or program logic modules using modern field interface protocols.

Information aspect of constructing an automated process control system for heat supply

During the development, special attention was paid to the information aspect of constructing an automated process control system for heat supply. The completeness of the description of production technology and the perfection of information conversion algorithms are the most important part information support A process control system built on direct digital control technology. The information capabilities of automated process control systems for heat supply provide the ability to solve a set of engineering problems, which are classified as:

• by stages of the main technology (production, transport and consumption of thermal energy);
• for its intended purpose (identification, forecasting and diagnostics, optimization and management).

When creating an automated process control system for Minsk heating networks, it is planned to form an information field that will make it possible to quickly solve the entire complex of the above problems of identification, forecasting, diagnostics, optimization and management. At the same time, information provides the ability to solve system problems of the upper management level with the further development and expansion of the process control system as the corresponding technical services are included to support the main technological process.

In particular, this applies to optimization problems, i.e. optimization of thermal and electrical energy, modes of supply of thermal energy, flow distribution in heating networks, modes of operation of the main technological equipment of heat sources, as well as calculation of rationing of fuel and energy resources, energy accounting and operation, planning and forecasting of the development of the heat supply system. In practice, the solution of some problems of this type is carried out within the framework of the enterprise's automated control system. In any case, they must take into account the information obtained in the course of solving direct technological process control problems, and the created process control system must be informationally integrated with other information systems of the enterprise.

Software object programming methodology

Construction software control system, which is an original development of the center team, is based on the software-object programming methodology: program objects are created in the memory of control and operator stations that display real processes, units and measuring channels of an automated technological object. The interaction of these software objects (processes, units and channels) with each other, as well as with operational personnel and with technological equipment, in fact, ensures the functioning of heating network elements according to predefined rules or algorithms. Thus, the description of algorithms comes down to a description of the most essential properties of these software objects and methods of their interaction.

Synthesis of the structure of the control system of technical objects is based on the analysis of the technological diagram of the control object and detailed description technologies of basic processes and functioning inherent this object generally.

A convenient tool for compiling this type of description for heat supply facilities is the methodology of mathematical modeling at the macro level. In the process of compiling a description of technological processes, a mathematical model, a parametric analysis is performed and a list of regulated and controlled parameters and regulatory bodies is determined.

The regime requirements of technological processes are specified, on the basis of which the boundaries of permissible ranges of changes in regulated and controlled parameters and requirements for the selection of actuators and regulatory bodies are determined. Based on the generalized information, an automated object control system is synthesized, which, when using the direct digital control method, is built on a hierarchical principle in accordance with the hierarchy of the control object.

ACS of the district boiler house

Thus, for a district boiler house (Fig. 2), the automated control system is built on the basis of two classes.

The upper level is the operator station “Kotelnaya” (OPS “Kotelnaya”) - the main station that coordinates and controls subordinate stations. OPS “Boiler backup” is a hot standby station, which is constantly in the mode of listening and recording traffic from the main OPS and its subordinate ACS. Its database contains current parameters and complete historical performance data working system management. At any time, the backup station can be assigned as the primary station with full traffic transfer to it and permission of supervisory control functions.

The lower level is a complex of automatic control stations united together with the operator station in a computer network:

• ACS "Kotloagregat" provides control of the boiler unit. As a rule, it is not reserved, since the thermal power of the boiler room is reserved at the boiler unit level.
• ACS "Network Group" is responsible for the thermal-hydraulic operating mode of the boiler room (control of a group of network pumps, a bypass line at the boiler room outlet, a bypass line, inlet and outlet valves of boilers, individual boiler recirculation pumps, etc.).
• ACS "Water Treatment" provides control of all auxiliary equipment of the boiler room necessary to feed the network.

For simpler objects of the heat supply system, for example, heating points and block boiler houses, the control system is built as a single-level one based on an automatic control station (ACS TsTP, ACS BMK). In accordance with the structure of heating networks, control stations of heating points are combined into a local computer network of the heating network district and are connected to the operator station of the heating network district, which, in turn, has an information connection with the operator station more high level integration.

Operator stations

The operator station software provides a user-friendly interface for operating personnel managing the operation of the automated technological complex. Operator stations have developed means of operational dispatch control, as well as mass memory devices for organizing short-term and long-term archives of the state of the parameters of the technological control object and the actions of operating personnel.

In cases of large information flows confined to operational personnel, it is advisable to organize several operator stations with a separate database server and, possibly, a communication server.

The operator station, as a rule, does not directly influence the control object - it receives information from technological stations and transmits to them directives of operational personnel or tasks (setpoints) of supervisory control, generated automatically or semi-automatically. It forms workplace operator of a complex facility, such as a boiler room.

The system being created automated control provides for the construction of an intelligent superstructure, which should not only monitor disturbances arising in the system and respond to them, but also predict the occurrence emergency situations and block their occurrence. When changing the topology of the heat supply network and the dynamics of its processes, it is possible to adequately change the structure of the distributed control system by adding new control stations and (or) changing software objects without changing the equipment configuration of existing stations.

Efficiency of automated process control system of heat supply system

An analysis of the experience of operating automated process control systems at heat supply enterprises 1 in a number of cities in Belarus and Russia, carried out over the past twenty years, showed them economic efficiency and confirmed viability decisions taken in architecture, software and hardware.

In terms of their properties and characteristics, these systems meet the requirements of the smart grid ideology. Nevertheless, work is constantly underway to improve and develop the automated control systems being developed. The introduction of automated process control systems for heat supply increases the reliability and efficiency of central heating systems. The main savings in fuel and energy resources are determined by the optimization of thermal-hydraulic modes of heating networks, operating modes of the main and auxiliary equipment of heat sources, pumping stations and heating points.

Literature

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4. Monakhov G.V. Modeling control of heating networks modes. Moscow: Energoatomizdat, 1995. 224 p.
5. Sednin V. A. Theory and practice of creating automated heat supply control systems. Minsk: BNTU, 2005. 192 p.
6. Sednin V. A. Introduction of automated process control systems as a fundamental factor in increasing the reliability and efficiency of heat supply systems // Technology, equipment, quality. Sat. mater. Belarusian Industrial Forum 2007, Minsk, May 15–18, 2007 / Expoforum - Minsk, 2007. pp. 121–122.
7. Sednin V. A. Optimization of parameters of the temperature schedule of heat supply in heating systems // Energetics. News of the Supreme educational institutions and energy associations of the CIS. 2009. No. 4. P. 55–61.
8. Sednin V. A. Concept of creating an automated control system for technological processes of Minsk thermal networks / V. A. Sednin, A. V. Sednin, E. O. Voronov // Increasing the efficiency of power equipment: Materials of a scientific-practical conference, in 2 T. T. 2. 2012. pp. 481–500.

1 Created by the team of the Research and Innovation Center for Automated Control Systems in Thermal Power Engineering and Industry of the Belarusian National Technical University.