Heat source configuration and operation adjustment method considering heat dynamic transfer characteristics

Abstract

The application provides a heat source configuration and operation adjusting method considering heat dynamic transmission characteristics, considers delay time and heat loss of heat source heat supply in a pipe network, simultaneously considers hysteresis of building heat load, proposes a concept of comprehensive delay time, and based on the comprehensive delay time, the heat load is pushed, and the heat source heat supply meets the sum of the heat load after the heat load of each heat exchange station is pushed by the comprehensive delay time, so as to achieve the purpose of supply-demand balance. The application realizes peak-shaving of the heat load of each heat exchange station, reduces the configuration capacity of the heat source, and improves the operation quality of the system.

Description

Technical Field

[0001] This invention belongs to the field of heat source control technology, specifically relating to a heat source configuration and operation regulation method that considers the dynamic heat transfer characteristics. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Currently, the heat source configuration capacity of the heating system is mainly determined by accumulating the design load of each terminal building; the operation and regulation of the heat source mainly adopts the steady-state heating method, that is, by monitoring the real-time outdoor temperature, estimating the heat load of each heat exchange station, and accumulating it to obtain the real-time heat supply of the heat source.

[0004] However, the transmission of heat from the heat source to each heat exchange station involves varying transmission and distribution delays and heat loss. Furthermore, due to the thermal inertia of buildings, changes in building heat load lag behind changes in outdoor temperature. Therefore, conventional heat source configuration methods can lead to an over-configuration of heat source capacity; steady-state operation and regulation will also result in a mismatch between supply and demand for end users, causing energy waste and a decline in heating quality. Summary of the Invention

[0005] To address the aforementioned problems, this invention proposes a heat source configuration and operation regulation method that considers the dynamic heat transfer characteristics. This invention considers the delay time and heat loss during heat source transmission within the pipe network, as well as the lag in building heat load, and proposes the concept of a comprehensive load delay time for heat exchange stations (hereinafter referred to as "comprehensive delay time"). Based on this comprehensive delay time, the heat load is shifted, and the heat source supply satisfies the sum of the heat loads shifted over each comprehensive delay time, thereby achieving a supply-demand balance. This invention enables peak-shifting of heat loads at each heat exchange station, reduces the required heat source capacity, and improves system operational quality.

[0006] According to some embodiments, the present invention adopts the following technical solution:

[0007] A method for heat source configuration and operation regulation considering dynamic heat transfer characteristics includes the following steps:

[0008] Calculate the transmission and distribution delay time and the building load lag time, and combine the two to obtain the overall delay time;

[0009] The heating curve is corrected based on the comprehensive delay time.

[0010] Based on the revised heating curve, configure the heat source capacity and control the operation of the heat exchange station.

[0011] As an alternative implementation, the comprehensive delay time is the difference between the heat transmission and distribution delay time from the heat source to the corresponding heat exchange station and the building load lag time within the heat exchange station.

[0012] As an alternative implementation method, the process of correcting the heating curve includes, taking into account the comprehensive delay time of each heat exchange station, shifting the hourly heat load curve of each heat exchange station accordingly, which is calculated based on outdoor parameters without considering the building's thermal inertia.

[0013] As an alternative implementation, the process of correcting the heating curve also includes obtaining the final heating curve based on the hourly heat load curves of each shifted heat exchange station.

[0014] As a further defined implementation method, considering the impact of the overall delay time, the hourly heat supply of the heat source should meet the sum of the hourly heat loads of each heat exchange station after the overall delay time.

[0015] As a further defined implementation, the final heat supply curve is determined by the maximum value of the sum of hourly heat loads after considering the comprehensive delay time of each heat exchange station when determining the peak heat supply of the heat source.

[0016] As an alternative implementation method, when the heat loss of the pipeline network is taken into account during the process of correcting the heating curve, the heat supply of the heat source will shift upward based on the heat loss, and the magnitude of the upward shift depends on the size of the heat loss.

[0017] As an alternative implementation, the process of correcting the heating curve is offset according to the comprehensive delay time of each adjustment cycle.

[0018] As an alternative implementation method, the specific process of configuring the heat source capacity and controlling the operation of the heat exchange station includes: calculating the heat output of the heat exchange station based on the detected secondary network supply and return water temperatures and flow rates; when the heat output of the heat exchange station is greater than the building heat load, reducing the water supply flow rate entering the heat exchange station to reduce the heat output of the heat exchange station; when the heat output of the heat exchange station is less than the building heat load, increasing the heat output of the heat exchange station to ensure a balance between supply and demand.

[0019] As an alternative implementation, when the heating system is a directly connected system, the heat exchange station in the method can be replaced with a building.

[0020] A heat source configuration and operation regulation system considering dynamic heat transfer characteristics, comprising:

[0021] The integrated delay time calculation module is configured to calculate the transmission and distribution delay time and the building load lag time, and combine the two to obtain the integrated delay time;

[0022] The heating curve optimization module is configured to correct the heating curve based on the comprehensive delay time;

[0023] The operation adjustment module is configured to configure the heat source capacity and control the operation of the heat exchange station according to the revised heating curve.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] This invention considers the delay time and heat loss during heat transfer within the pipe network, as well as the lag in building heat load. It proposes the concept of a comprehensive delay time and establishes a heat source configuration and operation regulation method that considers the dynamic characteristics of heat transfer. Based on this comprehensive delay time, the heat load is shifted, and the heat supply from the heat source satisfies the sum of the shifted heat loads at each heat exchange station, thus achieving a supply-demand balance. This invention can achieve peak heat load staggering at each heat exchange station, reduce the required heat source capacity, improve system operation quality, and contribute to reducing energy waste and promoting green energy.

[0026] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0027] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0028] Figure 1 Schematic diagram of hourly heat load and heat supply from conventional heat source schemes for different heat exchange stations;

[0029] Figure 2 Schematic diagram of different heat exchange stations and transmission / distribution delay times;

[0030] Figure 3 A schematic diagram showing the heat supply from the heat source with a comprehensive delay time and the hourly heat load of different heat exchange stations;

[0031] Figure 4 A comparison chart showing peak heating demand with and without considering the overall delay time;

[0032] Figure 5 This is a schematic diagram of control strategy a for the heat exchange station;

[0033] Figure 6 This is a schematic diagram of the hot water network in this embodiment;

[0034] Figure 7 This is a graph showing the temperature change on a specific day in this embodiment;

[0035] Figure 8This is a graph showing the hourly heat load changes of each heat exchange station in this embodiment;

[0036] Figure 9 This is a graph showing the hourly variation of the heat supply to each heat exchange station after considering the overall delay time in this embodiment.

[0037] Figure 10 This is a graph showing the hourly change in heat supply from the heat source before and after the delay time in this embodiment;

[0038] Figure 11 This is a flowchart illustrating the process of this embodiment. Detailed Implementation

[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0040] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0041] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0042] Example 1

[0043] During the routine operation and adjustment of the heating system, the hourly heat supply of the heat source should meet the sum of the hourly heat loads of all heat exchange stations in the heating area in real time, as shown in equation (1).

[0044]

[0045] In the formula: Q hs,i,τ The hourly heat supply of heat source i, kW; Q ex,j,τ Let τ be the hourly heat load of heat exchange station j, in kW; τ be the time, in h; m be the number of heat sources; and n be the number of heat exchange stations.

[0046] Within the same heating area, the outdoor temperature exhibits a generally consistent pattern over time, and the peak heat load of each heat exchange station can be considered to occur at the same moment τ0, such as... Figure 1 As shown. In Figure 1 In this equation, the peak heating value of the heat source is equal to the sum of the peak heat load values ​​of each heat exchange station at time τ0, in order to meet the heat load demand of each heat exchange station, as shown in equation (2).

[0047]

[0048] In the formula: The peak value of the heat source during normal heating, in kW; Let τ0 be the peak heat load of heat exchange station j at time τ0, in kW.

[0049] When the outdoor temperature corresponding to τ0 is the outdoor design temperature for heating... The configuration capacity of the heat source.

[0050] In the actual operation of a heating system, the heat supplied by the heat source is transferred to each heat exchange station through the pipeline network. The heat medium experiences varying delay times and heat loss during its distribution from the heat source to each heat exchange station. Figure 2 As shown. Figure 2 Δτ ex This represents the transmission and distribution delay time of the heat exchange station relative to the heat source. The delay time and heat loss of dynamic transmission in the pipeline network can be calculated using the corresponding dynamic thermodynamic model.

[0051] Because heating pipelines are often long, with transmission and distribution delays of up to several hours, the amount of heat required from the heat source varies significantly at different times for each heat exchange station. Furthermore, heat loss can also lead to insufficient heat supply from the heat source, affecting the system's heating quality.

[0052] Meanwhile, due to the thermal inertia of buildings, indoor temperature changes (building heat load) lag behind outdoor temperature changes. This lag time is primarily determined by numerous factors, including the total thermal inertia index of the building envelope, the heat storage coefficient of each layer's materials, and the internal and external convective heat transfer coefficients. It can be calculated using many established building load models. When the types of buildings supplied by the same heat exchange station are essentially the same, the building load lag time can be considered consistent. Furthermore, since the secondary network is generally small, its transmission and distribution delay time is relatively small compared to the primary network's transmission and distribution delay time and the building load lag time, and can be ignored.

[0053] To address the above situation, this embodiment proposes the concept of comprehensive delay time and establishes a heat source configuration and operation regulation method that considers the dynamic heat transfer characteristics, specifically as follows: Figure 11 As shown below. A detailed explanation follows:

[0054] The overall delay time is composed of the transmission and distribution delay time and the building load lag time, as detailed in equation (3).

[0055] Δτ z,j =Δτ ex,j -Δτ b,j (3)

[0056] In the formula: Δτ z,j Let h be the overall delay time of heat exchange station j; Δτ ex,jLet h be the heat transfer delay from the heat source to the heat exchange station j; Δτ b,j Let h be the lag time of the building load within heat exchange station j.

[0057] In the method proposed in this disclosure, when assessing the heat supplied to a heat exchange station, the heat source side considers the hourly heat load with a comprehensive delay time, such as... Figure 3 As shown. Figure 3 In the diagram, the solid line represents the hourly heat load of the heat exchange station calculated based on outdoor parameters without considering building thermal inertia; the dashed line represents the heat supplied to each heat exchange station by shifting the solid line left and right after considering the comprehensive delay time. Since the magnitude of the transmission and distribution delay time and the building load delay time are determined by the actual operating conditions, Δτ... z,j The sign is uncertain, that is... Figure 3 The dotted line in the image may shift to the left or right. Figure 3 (Only the case of shifting left is shown in the image).

[0058] Considering the impact of the comprehensive delay time, the hourly heat supply of the heat source should meet the sum of the hourly heat loads of each heat exchange station after the comprehensive delay time, as shown in equation (4).

[0059]

[0060] In the formula: For heat exchange station j, the comprehensive delay time Δτ z,j The hourly heat load after that, in kW.

[0061] The formula for calculating the peak heating capacity of the heat source considering the comprehensive delay time is shown in equation (5).

[0062]

[0063] In the formula: To account for the peak heating supply of the heat source with a comprehensive delay time, kW.

[0064] Comparison of conventional solutions and hourly heating supply from heat sources that consider the time delay for integration, for example Figure 4 As shown. At the same time, when considering the heat loss of the pipeline network, the heat supply of the heat source will also shift upwards to some extent based on the heat loss, and the extent of the upward shift depends on the magnitude of the heat loss.

[0065] After considering the overall delay time, the total heat supply of the heat source remains unchanged within the time period, but the heat load of each heat exchange station is staggered, and the peak heat supply of the heat source is reduced. Compared to peak heating season Reducing ΔQ leads to a slight increase in the peak heating value, resulting in a flatter overall heating curve. The main reason for ΔQ is the different overall delay times of each heat exchange station, which causes the heat load of each station to be staggered. Therefore, under the design conditions, the design heat supply of the heat source is also reduced accordingly, thereby reducing the heat source configuration capacity.

[0066] To ensure that the heat supply from the heat source, after considering the comprehensive delay time, meets the heat load demand of the terminal buildings, the heat extraction of the heat exchange station needs to be controlled. The operation and regulation strategy a for the heat exchange station provided in this embodiment is as follows: Figure 5 As shown. This adjustment strategy is to ensure that the heat exchange station extracts heat according to the building load. For example... Figure 5 As shown, the controller adjusts the opening of the primary-side regulating valve by detecting the supply and return water temperatures and flow rates of the secondary network to ensure supply and demand matching at the heat exchange station. Based on the detected supply and return water temperatures and flow rates, the heat output of the heat exchange station is calculated. When the heat output of the heat exchange station exceeds the building's heat load, the opening of the primary-side regulating valve decreases to reduce the water supply flow rate into the heat exchange station, thereby reducing the heat output. When the heat output of the heat exchange station is less than the building's heat load, the opening of the regulating valve increases to increase the heat output, thus achieving the goal of supply and demand balance.

[0067] After adjustment using heat exchange station operation strategy a, the hydraulic conditions of the heating system will change within each adjustment cycle, resulting in changes in transmission and distribution delay time and overall delay time. Figure 3 The load curve will no longer be shifted as a whole, but will be shifted according to the comprehensive delay time of each adjustment cycle.

[0068] The above embodiments describe and illustrate the primary network of an indirectly connected heating system. In other embodiments, when the heating system is a directly connected system, it is only necessary to replace the heat exchange station with a building and adjust it using the method disclosed in this embodiment.

[0069] Example 2

[0070] A heat source configuration and operation regulation system considering dynamic heat transfer characteristics, comprising:

[0071] The integrated delay time calculation module is configured to calculate the transmission and distribution delay time and the building load lag time, and combine the two to obtain the integrated delay time;

[0072] The heating curve optimization module is configured to correct the heating curve based on the comprehensive delay time;

[0073] The operation adjustment module is configured to configure the heat source capacity and control the operation of the heat exchange station according to the revised heating curve.

[0074] Example 3

[0075] This embodiment uses the method described in Embodiment 1 or the system described in Embodiment 2, selecting a certain hot water network for application, such as... Figure 6 As shown in the figure. The designed supply and return water temperatures are 130℃ and 70℃, respectively. The available pressure head for each heating station is 117600Pa.

[0076] The hot water flow velocity and distribution delay time in each pipe section can be obtained through hydraulic calculations, as shown in Table 1.

[0077] Table 1 Summary of Hot Water Flow Velocity and Distribution Delay Time in Each Pipe Section

[0078]

[0079] The calculation of indoor temperature lag time due to building thermal inertia is complex and will not be considered in this case. The hourly heat load of each heat exchange station can be obtained by equation (6). The design heat load is obtained by multiplying the area heat index by the heating area. In this method, heat loss has been taken into account in the selection of the area heat index.

[0080]

[0081] In the formula: t n Indoor design temperature, °C; t τ Outdoor temperature, °C; t w ′ represents the outdoor calculated temperature, in °C; Q j ′ represents the design heat load of heat exchange station j, in kW.

[0082] By consulting relevant design manuals, the outdoor design temperature for winter heating in the city where the case study is located is -14.5℃, while the indoor design temperature for general civil buildings is selected as 20℃. Taking February 18, 2023 as an example, the temperature change in that area is as follows: Figure 7 As shown. Combining equation (6), the hourly heat load of each heat exchange station on that day is as follows: Figure 8 As shown.

[0083] By taking into account the transmission and distribution delay times of each pipe section in Table 1, combined with the local air temperature after the transmission and distribution delay times of each heat exchange station, and equation (6), the hourly heat supply from the heat source to each heat exchange station after considering the comprehensive delay time can be obtained, such as... Figure 9 As shown.

[0084] Combining equations (1) and (4), the hourly heating capacity of a conventional heating system and a heat source considering the overall delay time is as follows: Figure 10 As shown, when the heating system takes into account the comprehensive delay time of each heat exchange station, the peak heating capacity of the heat source is reduced by 6MW compared to the conventional heating scheme, accounting for 5.5% of the total heating capacity, and the peak heating time is brought forward by 5 hours. The hourly heating curve of the heat source tends to be flat, achieving the effect of peak shaving and valley filling.

[0085] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0086] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0087] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0088] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0089] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art without creative effort within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for heat source configuration and operation regulation considering dynamic heat transfer characteristics, characterized in that, Includes the following steps: Calculate the transmission and distribution delay time and the building load lag time, and combine the two to obtain the overall delay time; The comprehensive delay time is the difference between the heat transmission and distribution delay time from the heat source to the corresponding heat exchange station and the building load lag time within the heat exchange station. Based on the comprehensive delay time, the heating curve is corrected; the process of correcting the heating curve includes, taking into account each comprehensive delay time, shifting the hourly heat load curve of each heat exchange station calculated based on outdoor parameters without considering building thermal inertia accordingly. The process of correcting the heating curve also includes obtaining the final heat source heating curve based on the hourly heat load curves of each heat exchange station after each shift; the final heat source heating curve is determined by the maximum value of the sum of hourly heat loads after considering the comprehensive delay time of each heat exchange station when determining the peak heat supply of the heat source. Based on the final heat source heat supply curve, configure the heat source capacity and control the operation of the heat exchange station; The specific process of configuring heat source capacity and controlling the operation of heat exchange stations includes: calculating the heat output of the heat exchange station based on the detected secondary network supply and return water temperatures and flow rates; when the heat output of the heat exchange station is greater than the building heat load, reducing the water supply flow rate into the heat exchange station to reduce the heat output of the heat exchange station; when the heat output of the heat exchange station is less than the building heat load, increasing the heat output of the heat exchange station to ensure supply and demand balance.

2. The heat source configuration and operation regulation method considering dynamic heat transfer characteristics as described in claim 1, characterized in that, Considering the impact of the overall delay time, the hourly heat supply of the heat source should meet the sum of the hourly heat loads of each heat exchange station after the overall delay time.

3. The heat source configuration and operation regulation method considering dynamic heat transfer characteristics as described in claim 1, characterized in that, When correcting the heating curve, after considering the heat loss of the pipeline network, the heat supply of the heat source will shift upward based on the heat loss, and the extent of the upward shift depends on the magnitude of the heat loss.

4. The heat source configuration and operation regulation method considering dynamic heat transfer characteristics as described in claim 1, characterized in that, The process of correcting the heating curve is offset based on the comprehensive delay time of each adjustment cycle.

5. The heat source configuration and operation regulation method considering dynamic heat transfer characteristics as described in claim 1, characterized in that, When the heating system is a direct connection system, the heat exchange station in the method is replaced by a building.

6. A heat source configuration and operation regulation system considering the dynamic heat transfer characteristics, characterized in that, include: The integrated delay time calculation module is configured to calculate the transmission and distribution delay time and the building load lag time, and combine the two to obtain the integrated delay time; The comprehensive delay time is the difference between the heat transmission and distribution delay time from the heat source to the corresponding heat exchange station and the building load lag time within the heat exchange station. The heating curve optimization module is configured to correct the heating curve based on the comprehensive delay time. The process of correcting the heating curve includes taking into account each comprehensive delay time and performing corresponding translation on the hourly heat load curve of each heat exchange station calculated based on outdoor parameters without considering the building thermal inertia. The process of correcting the heating curve also includes obtaining the final heat source heating curve based on the hourly heat load curves of each heat exchange station after each shift; the final heat source heating curve is determined by the maximum value of the sum of hourly heat loads after considering the comprehensive delay time of each heat exchange station when determining the peak heat supply of the heat source. The operation adjustment module is configured to configure the heat source capacity and control the operation of the heat exchange station according to the final heat source heat supply curve; The specific process of configuring heat source capacity and controlling the operation of heat exchange stations includes: calculating the heat output of the heat exchange station based on the detected secondary network supply and return water temperatures and flow rates; when the heat output of the heat exchange station is greater than the building heat load, reducing the water supply flow rate into the heat exchange station to reduce the heat output of the heat exchange station; when the heat output of the heat exchange station is less than the building heat load, increasing the heat output of the heat exchange station to ensure supply and demand balance.

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