Method and system for extracting and condensing unit to cooperate with heat supply network peak regulation

Abstract

The invention belongs to the field of peak shaving of cogeneration units, and provides an extraction condensing unit collaborative heat supply network peak shaving method and system.The extraction condensing unit collaborative heat supply network peak shaving method comprises the steps that the electric load and heat supply steam extraction amount data of an extraction condensing unit within a period of time are obtained, the space is adjusted according to the thermoelectric load of the extraction condensing unit, and the target electric load is compared with the maximum electric load and the minimum electric load; a cooperative heat supply network peak regulation mode is determined, and the corresponding adjusted heat supply air suction rate is calculated; the adjusted heat supply steam extraction amount is substituted into the heat supply network equivalent mathematical model, an indoor temperature change curve of each heat user is calculated, if the indoor temperature of each heat user exceeds the indoor standard, the adjusted heat supply amount is reduced for iterative calculation till the indoor temperature of each heat user meets the indoor standard all the time, and the indoor temperature of each heat user does not meet the indoor standard all the time. Outputting the final heat supply air extraction rate and the power generation power of the corresponding extraction condensing unit; based on the difference and complementarity of the unit power response and the heat consumer indoor temperature response on the time scale, the load flexibility adjustment of the extraction condensing unit is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of peak load regulation of cogeneration units, and in particular relates to a peak load regulation method and system for a condensing unit in coordination with a heat network. Background Art

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

[0003] Since renewable energy generation is random, intermittent and uncontrollable, the power system needs to have corresponding peak-shaving capacity as a flexible reserve to meet the consumption of renewable energy. As the main form of power supply in Shandong Province, coal-fired power units inevitably undertake the task of peak-shaving. Due to heating needs, coal-fired units mostly use extraction and condensing mode for combined heat and power generation during the heating season. Due to the "heat-electricity coupling" mechanism, the peak-shaving capacity of the extraction and condensing units is subject to certain constraints, and the ability to provide flexibility support for the power grid is limited.

[0004] Although the existing units have improved their flexibility adjustment capabilities through flexibility transformation technology or coupling electric boilers, heat pumps, heat storage and other equipment, the above methods not only require expensive transformation or investment costs, but are also mainly used to improve the downward peak-shaving capacity of coal-fired units, that is, to reduce the power generation of coal-fired units to absorb excess renewable energy generation. However, with the development of urbanization, social electricity consumption has increased significantly. Therefore, in order to meet the electricity needs of the whole society, coal-fired units not only need to reduce load when renewable energy generation is in excess, but also need to generate peak power when renewable energy generation is insufficient to make up for the "power gap".

[0005] However, the existing unit peak-shaving methods do not take into account the differences and complementarities in time scale between the unit power response and the indoor temperature response of the heat user, making it difficult to utilize the huge thermal network heat storage resources for peak power generation when renewable energy generation is insufficient. Summary of the invention

[0006] In order to solve the above problems, the present invention proposes a method and system for peak-shaving of extraction condensing units in coordination with the heating network. The flexible peak-shaving method of the present invention is based on the difference and complementarity in time scale between the power response of the unit and the indoor temperature response of the heat user. While taking into account the experience of the heat users and meeting the national heating standards, the load flexibility adjustment of the extraction condensing unit is achieved by making full use of the heat storage and thermal inertia of the heating network. The flexible peak-shaving of the extraction condensing unit is achieved under the premise of ensuring the experience of the heat users and meeting the national heating standards.

[0007] According to some embodiments, the first solution of the present invention provides a method for peak load regulation of a heat network in cooperation with an extraction condensing unit, which adopts the following technical solution:

[0008] A method for peak load regulation of a heat network using an extraction condensing unit, comprising:

[0009] Obtain the thermal and electric load adjustment diagram space of the extraction and condensing units and construct an equivalent mathematical model of the heat network;

[0010] Obtain the data of the electric load and heating steam extraction volume of the condensing unit over a period of time, and adjust the thermal and electric load of the condensing unit to obtain the maximum and minimum electric loads that the condensing unit can reach under the current heating steam extraction volume;

[0011] By comparing the target electric load with the maximum electric load and the minimum electric load, the peak load regulation mode of the collaborative heating network is determined and the corresponding adjusted heating extraction volume is calculated;

[0012] The adjusted heating extraction volume is substituted into the equivalent mathematical model of the heating network to calculate the indoor temperature change curve of each heat user. If the indoor temperature of the heat user exceeds the indoor standard, the adjusted heating volume will be reduced for iterative calculation until the indoor temperature of the heat user always meets the indoor standard, and the final heating extraction volume and the corresponding power generation power of the condensing unit are output.

[0013] Furthermore, the thermal power load adjustment diagram space of the extraction and condensing unit is obtained to construct an equivalent mathematical model of the heat network, specifically:

[0014] Obtain the thermal and electric load adjustment diagram space of the condensing unit, and calculate the delay time from the change in the heating steam extraction volume to the heat user's perception of the indoor temperature change;

[0015] According to the specific distribution of heat users along the heat network pipeline, a heat network schematic diagram is formed, and the heat network schematic diagram is simplified using the node method to obtain a simplified heat network model;

[0016] Calculate the basic heat load of each heat user according to the building type, heating area and whether energy-saving measures are adopted;

[0017] Obtain local weather data, and use the weather data to correct the basic heat load of heat users to obtain the corrected basic heat load;

[0018] Based on the corrected basic heat load and the simplified heating network model, the equivalent mathematical model of the heating network is obtained.

[0019] Furthermore, the delay time from when the amount of steam extraction for heating changes to when the heat user begins to perceive the change in indoor temperature is composed of two parts of delay, the primary network and the secondary network;

[0020] The primary network considers the primary network pipeline temperature transmission delay time and primary network pipeline temperature loss;

[0021] The secondary network takes into account the time delay caused by the heat exchange process in the heat exchange station located between the primary network and the secondary network.

[0022] Further, the primary network pipeline temperature transmission delay time is obtained by multiplying the product of the primary network heat delay coefficient and the primary network pipeline length by the primary network heat medium flow rate;

[0023] The primary network pipeline temperature loss is determined based on the difference between the primary heat network pipeline starting temperature and the ambient temperature, the total heat transfer coefficient of the pipeline per unit length, the constant pressure specific heat capacity of water, and the primary network heat medium flow rate.

[0024] Furthermore, the time delay caused by the heat exchange process of the heat exchange station between the primary network and the secondary network is to obtain the dynamic response curve of the heat exchange station connecting the primary network and the secondary network, and its dynamic characteristics are approximated as an inertia delay transfer function with a time constant as , so as to characterize the change law of the secondary network temperature after the primary network heat changes.

[0025] Furthermore, the basic heat load of each heat user is calculated according to the building type, heating area and whether energy-saving measures are adopted of the heat user, specifically:

[0026] Determine the comprehensive heating index based on the building type of the heat user and whether energy-saving measures are adopted;

[0027] The basic heat load of each heat user is determined by the product of the comprehensive heating index and the heating area of ​​the heat user.

[0028] Furthermore, the local weather data is obtained, and the basic heat load of the heat user is corrected using the weather data to obtain the corrected basic heat load, which is specifically:

[0029] Determine the heat load correction factor based on the indoor calculated temperature, outdoor calculated temperature and outdoor real-time temperature;

[0030] The corrected basic heat load is determined by multiplying the heat load correction coefficient by the basic heat load of each heat user.

[0031] Furthermore, by comparing the target electric load with the maximum electric load and the minimum electric load, the method of collaborative heating network peak regulation is determined and the corresponding adjusted heating extraction volume is calculated, specifically:

[0032] If the target power load is between the maximum power load and the minimum power load, there is no need to adopt the heat network coordination method, and the target power load can be achieved by relying on the adjustment ability of the condensing unit itself;

[0033] If the target electric load is greater than the maximum electric load, it is necessary to coordinate with the heat network to adjust, and use the difference between the two as the increased power generation power, and subtract the heat supply and extraction steam volume of the condensing unit from the quotient of the increased power generation power and the thermoelectric conversion coefficient to obtain the adjusted heat supply and extraction steam volume;

[0034] If the target electric load is less than the minimum electric load, the heating network conditions must be coordinated, and the difference between the two is used as the reduced power generation power. The heat extraction volume of the condensing unit is summed with the quotient of the reduced power generation power and the electric heat conversion coefficient to obtain the adjusted heat extraction volume.

[0035] Furthermore, the adjusted heat extraction steam volume is substituted into the heat network equivalent mathematical model to calculate the indoor temperature change curve of each heat user, specifically:

[0036]

[0037] Where M b is the weight of the heat user's building, in kg; c b is the specific heat capacity of the heat user building, in kJ / (kg·℃); Q in and Q out They are respectively the heat entering the heat user's building through the secondary network water supply pipeline per unit time and the heat dissipated by the heat user's building, both in MW.

[0038] According to some embodiments, the second solution of the present invention provides a peak load regulation system of a heat network coordinated by an extraction condensing unit, which adopts the following technical solution:

[0039] A peak load regulation system of a heat network coordinated by an extraction condensing unit, comprising:

[0040] A heat network model building module is configured to obtain a thermal power load adjustment diagram space of the extraction and condensing units and build an equivalent mathematical model of the heat network;

[0041] The limiting calculation module is configured to obtain the electric load and heating steam extraction data of the condensing unit over a period of time, and obtain the maximum and minimum electric loads that the unit can reach under the current heating steam extraction according to the thermal and electric load adjustment space of the condensing unit;

[0042] The coordinated peak-shaving module is configured to determine the coordinated peak-shaving mode of the heat network and calculate the corresponding adjusted heating extraction volume by comparing the target electric load with the maximum electric load and the minimum electric load;

[0043] The heating extraction volume determination module is configured to substitute the adjusted heating extraction volume into the equivalent mathematical model of the heating network, calculate the indoor temperature change curve of each heat user, and if the indoor temperature of the heat user exceeds the indoor standard, the adjusted heating volume will be reduced for iterative calculation until the indoor temperature of the heat user always meets the indoor standard, and output the final heating extraction volume and the corresponding power generation power of the condensing unit.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The present invention applies the heat network to the field of peak load regulation of heating units, and proposes a flexible peak load regulation method for extraction condensing units in coordination with the heat network. Based on the difference and complementarity in time scale between the unit power response and the indoor temperature response of the heat user, and considering the heat user experience and national heating standards, the flexible peak load regulation of the extraction condensing units is achieved by making full use of the heat storage and thermal inertia of the heat network.

[0046] The present invention simplifies the actual heat network into an equivalent mathematical model consisting of a series of nodes and delay links. The model has good versatility and computational efficiency, and is easy to develop. The addition or deletion of heat users can be achieved by modifying the nodes of the equivalent mathematical model; the modification of the pipe network length can be achieved by modifying the delay time constant in the equivalent mathematical model.

[0047] The peak load regulation method proposed in the present invention has strong applicability. It is not only applicable to various subcritical, supercritical, and ultra-supercritical coal-fired units that realize heating through steam extraction, but also to nuclear power units that also realize heating through steam extraction. It is not only applicable to the coordinated operation of heating by a single unit, but also to the situation where multiple thermal power units jointly provide heating. The method has simple control logic, high degree of automation, and is not limited to a specific programming language. Therefore, it is compatible with the existing system hardware of the power plant, easy to integrate into the existing control system of the unit, and does not require additional equipment investment, and has strong scalability.

[0048] The peak-shaving method proposed in the present invention can be used in conjunction with a heat storage device, which can play a certain buffering role in the changes in the circulating water temperature of the heating network, thereby slowing down the speed of change of the indoor temperature of the heat users, thereby further improving the power size and duration of the flexible peak-shaving of the condensing unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0050] Figure 1 This is a schematic flow chart of a peak-shaving method for a heat network in which an extraction condensing unit is coordinated, according to an embodiment of the present invention;

[0051] Figure 2 It is the thermal and electric load adjustment space of the condensing unit in the embodiment of the present invention;

[0052] Figure 3 is the dynamic response curve of the heat exchange station in the embodiment of the present invention and the response curve approximated by the inertial delay transfer function;

[0053] Figure 4 is a schematic diagram of a heat network in an embodiment of the present invention;

[0054] Figure 5 is an equivalent mathematical model of the heat network in the embodiment of the present invention;

[0055] Figure 6 It is the Matlab / Simulink implementation of the equivalent mathematical model of the heat network in the embodiment of the present invention;

[0056] Figure 7 is weather data in an embodiment of the present invention;

[0057] Figure 8 is the actual electric load, target electric load, and heating steam extraction volume of the condensing unit in one day in the embodiment of the present invention;

[0058] Fig. 9 is the thermal and electric load data of the condensing unit before and after the coordinated heating network in the embodiment of the present invention;

[0059] Fig.10 It is the indoor temperature change of all heat users during the coordinated heat network adjustment in the embodiment of the present invention. DETAILED DESCRIPTION

[0060] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0061] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0062] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0063] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0064] Embodiment 1

[0065] The present embodiment provides a method for peak-shaving of a heat network in coordination with a condensing unit. The present embodiment takes the method applied to a server as an example for illustration. It is understandable that the method can also be applied to a terminal, and can also be applied to a system including a terminal, a server, and a server, and is implemented through the interaction between the terminal and the server. The server can be an independent physical server, or a server cluster or a distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network servers, cloud communications, middleware services, domain name services, security services CDN, and big data and artificial intelligence platforms. The terminal can be a smart phone, a tablet computer, a laptop computer, a desktop computer, a smart speaker, a smart watch, etc., but is not limited thereto. The terminal and the server can be directly or indirectly connected via wired or wireless communication, which is not limited in this application. In the present embodiment, the method includes the following steps:

[0066] Obtain the thermal and electric load adjustment diagram space of the extraction and condensing units and construct an equivalent mathematical model of the heat network;

[0067] Obtain the data of the electric load and heating steam extraction volume of the condensing unit over a period of time, and adjust the thermal and electric load of the condensing unit to obtain the maximum and minimum electric loads that the condensing unit can reach under the current heating steam extraction volume;

[0068] By comparing the target electric load with the maximum electric load and the minimum electric load, the peak load regulation mode of the collaborative heating network is determined and the corresponding adjusted heating extraction volume is calculated;

[0069] The adjusted heating extraction volume is substituted into the equivalent mathematical model of the heating network to calculate the indoor temperature change curve of each heat user. If the indoor temperature of the heat user exceeds the indoor standard, the adjusted heating volume will be reduced for iterative calculation until the indoor temperature of the heat user always meets the indoor standard, and the final heating extraction volume and the corresponding power generation power of the condensing unit are output.

[0070] like Figure 1 As shown, the method described in this embodiment adopts the following technical solutions:

[0071] Step 1: Calculate the thermal and electric load adjustment space of the condensing unit, such as Figure 2 shown.

[0072] This step does not restrict the method of calculating the thermal power load adjustment space. According to the actual situation, the heating condition diagram method, steam-water balance equation method or other mechanism modeling methods can be selected, and the data-driven modeling method can also be used. If the heating first station of the thermal power plant is jointly undertaken by multiple extraction condensing units (without limiting the participation of other types of units, such as high back pressure transformation units, low pressure cylinder zero output units, bypass transformation units, etc.), it is necessary to obtain the thermal power load adjustment space of each coal-fired power unit and the thermal power load adjustment space of the whole plant.

[0073] Step 2: Calculate the delay time from the change in the amount of steam extraction for heating to the time when the heat user begins to perceive the change in indoor temperature. This delay time is mainly composed of the delay of the primary network and the secondary network.

[0074] Step 2-1: Since the primary network pipeline is long, it is necessary to consider the primary network pipeline temperature transmission delay time τ and the primary network pipeline temperature loss ΔT loss .

[0075]

[0076] In the formula, K delay is the primary network heat delay coefficient, L is the primary network pipeline length, m, v is the primary network heat medium flow rate, m / s. strat is the starting temperature of the primary heating network pipeline, T e is the ambient temperature, in degrees Celsius. λ is the total heat transfer coefficient per unit length of the pipe, in W / m·°C. P is the constant pressure specific heat capacity of water, in kJ / (kg·℃). m1 is the primary network heat medium flow rate, in kg / s.

[0077] Step 2-2: The secondary network pipeline is relatively short, so there is no need to consider the delay of temperature transmission in the secondary network pipeline for the time being, but the time delay caused by the heat exchange process of the heat exchange station between the primary network and the secondary network must be considered. The time delay of the secondary pipeline is reflected in the dynamic response curve. According to equations (3) and (4), the dynamic response curve of the heat exchange station connecting the primary network and the secondary network is obtained, and its dynamic characteristics are approximated as the inertia delay transfer function with a time constant of T To characterize the change of the secondary network temperature after the primary network heat changes. The dynamic response curve of the heat exchange station and the response curve after approximation by the inertia delay transfer function are as follows: Figure 3 shown.

[0078]

[0079] Q=m w1 c p (T strat -ΔT loss ) (4);

[0080] Where, M2 is the water storage capacity of the heat exchange station pipeline, kg. Q is the heat transferred from the primary network to the secondary network per unit time, MW. m w2 T is the heat medium flow rate of the secondary network pipeline, kg / s. w,in With T w,out Respectively represent the inlet and outlet water temperatures of the heat exchange station, both in ℃.

[0081] Step 3: Based on the specific distribution of heat users along the heat network pipeline, the following Figure 4 The heat network diagram shown in the figure is simplified into the following by using the node method. Figure 5 As shown in the figure, the equivalent mathematical model composed of multiple nodes is implemented in Matlab / Simulink, as shown in the figure. Figure 6 shown.

[0082] Step 4: According to the building type, heating area, and whether energy-saving measures are adopted, the basic heat load of each heat user is calculated based on the comprehensive heating index value stipulated by the state, as shown in formula (5).

[0083] Q design =S·CHI (5);

[0084] Where S is the heating area, m 2 CHI is the comprehensive heating index, W / m 2 The comprehensive heating index values ​​of various types of buildings are shown in Table 1.

[0085] Table 1 Comprehensive heating index value (unit: W / m2)

[0086]

[0087] It can be seen that the basic heat load of each heat user is calculated according to the building type, heating area and whether energy-saving measures are adopted, specifically:

[0088] Determine the comprehensive heating index based on the building type of the heat user and whether energy-saving measures are adopted;

[0089] The basic heat load of each heat user is determined by the product of the comprehensive heating index and the heating area of ​​the heat user.

[0090] Step 5: Obtain local weather data and correct the basic heat load of each heat user to the actual heat load according to formulas (6) and (7).

[0091] Q user =ε·Q design (6);

[0092]

[0093] Where ε is the heat load correction factor, t i Calculate the indoor temperature, t o Calculate the outdoor temperature, t a It is the real-time outdoor temperature in °C.

[0094] Step six: Calculate the heating steam extraction capacity of the unit after the coordinated heating network adjustment.

[0095] Step 6-1: Obtain the unit's electrical load and heating steam extraction data over a period of time.

[0096] Step 6-2: Adjust the space according to the thermal and electrical load of the unit to obtain the maximum electrical load P that the unit can reach under the current heating and extraction steam capacity. max With minimum electrical load P min .

[0097] Step 6-3: Set the target load P OB With P max and P min Compare.

[0098] If P OB In P max With P min There is no need to adopt the heat network coordination method, and the target power load can be achieved by relying on the unit's own adjustment ability.

[0099] If P OB >P max , then it is necessary to coordinate the heat network regulation, and the power generation power required to be increased is P OB -P max , then the heating extraction steam volume after adjustment of the collaborative heating network is calculated by formula (8).

[0100]

[0101] In the formula, m h With m H are the heat extraction steam volume of the condensing unit before and after adjustment, t / h. k is the thermoelectric conversion coefficient, which means: the power change caused by the change of unit heat extraction steam volume.

[0102] If P OB <P min , then it is necessary to coordinate the heat network regulation, and the power generation power that needs to be reduced is P min -P OB , then the heating extraction volume after adjustment of the collaborative heating network is calculated by formula (9).

[0103]

[0104] Step 6-4: Substitute the adjusted heat extraction volume of the collaborative heat network into the heat network equivalent mathematical model mentioned in step 3, and calculate the indoor temperature change curve of each heat user according to the following formula.

[0105]

[0106] Where M b is the weight of the heat user's building, in kg. b Q is the specific heat capacity of the heat user building, in kJ / (kg·℃). in and Q out They are respectively the heat entering the heat user's building through the secondary network water supply pipeline per unit time and the heat dissipated by the heat user's building, both in MW.

[0107] If the indoor temperature of the heat user is always between 16℃ and 24℃ as required by the Indoor Air Quality Standard (GB / T 18883-2022), the output m H ; If the maximum or minimum value of the indoor temperature of the heat user exceeds the required range, m H Gradually reduce, perform iterative calculation until the indoor temperature of the heat user always meets the range of 16℃~24℃, and output m H .

[0108] Step 6-5: According to the output m H , recalculate the power generation of the condensing unit and output it as the result of iterative calculation.

[0109] Step 6-6: If the heating source is connected to multiple thermal power units in a thermal power plant, m H The equivalent steam extraction capacity for heating of the whole plant needs to be distributed among the units involved in heating according to the change of the adjusted heating load, and calculated within the thermal load operation domain of the whole plant to obtain the maximum and minimum values ​​of the whole plant output after the corresponding heat load change. Repeat steps 6-3 to 6-5 to obtain the equivalent m of the whole plant. H , and then distribute the change of extraction steam volume among the units to obtain the adjusted operating conditions of each unit. In the load adjustment process, each unit also needs to meet the constraints of its own thermal and electric coupling characteristics.

[0110] In a typical embodiment, there is a 330MW extraction condensing unit, a heating source station, a regional heating network, including 6 heat exchange stations and 6 heat users. A flexible peak-shaving method for extraction condensing units in a coordinated heating network is provided to achieve flexible peak-shaving of extraction condensing units while ensuring the experience of heat users and complying with national heating standards.

[0111] according to Figure 1 The method flow shown adopts the following technical solutions:

[0112] Step 1: Establish the thermal system mechanism model of the extraction condensing unit through the steam-water balance equation and calculate the thermal power load adjustment space, such as Figure 2 shown.

[0113] Step 2: Calculate the delay time from the change in the amount of steam extraction for heating to the time when the heat user begins to perceive the change in indoor temperature. This delay time is mainly composed of the delay of the primary network and the secondary network.

[0114] Step 2-1: Calculate the primary network pipe temperature transmission delay time τ and the primary network pipe temperature loss ΔT according to equations (1) and (2). loss .

[0115] Among them, K delay =1.39, T strat =120℃, T e =0℃, v is 2.1m / s, λ=1.465W / (m·℃). In addition, the outlet water temperature of the heating primary station is 120℃, and the inlet water temperature is 90℃. The outlet water temperature of the secondary network is 60℃, and the inlet water temperature is 45℃.

[0116] Step 2-2: Approximate the dynamic response curve of the heat exchange station as an inertia delay transfer function with a time constant of 200 To characterize the change of the secondary network temperature after the primary network heat changes. The dynamic response curve of the heat exchange station and the response curve approximated by the inertia delay transfer function are detailed in the attached Figure 3 .

[0117] Step 3: According to the specific distribution of heat users along the heat network pipeline, form Figure 4 The heat network diagram shown in the figure is simplified into the following by using the node method. Figure 5 As shown in the figure, the equivalent mathematical model composed of multiple nodes is implemented in Matlab / Simulink, as shown in the figure. Figure 6 shown.

[0118] Step 4: Calculate the basic heat load of each heat user based on the comprehensive heating index value stipulated by the state. The heat network includes 6 heat exchange stations, corresponding to 6 heat users, including 3 residential areas, 2 commercial areas and 1 school. The heating area of ​​each heat user and whether energy-saving measures are adopted are shown in Table 2, and the distribution along the heat network is shown in Attachment Figure 4 .

[0119] Table 2 Heating area and energy-saving measures for each heat user in the heat network

[0120]

[0121] Referring to the comprehensive heating index values ​​stipulated by the state as shown in Table 1, the basic heat load of each heat user is calculated by formula (5).

[0122] The basic heat load of each heat user is:

[0123] Residence 1:

[0124] Residence 2:

[0125] Residence 3:

[0126] Business 1:

[0127] Business 2:

[0128] School 1:

[0129] Step 5: Local weather data such as Figure 7 As shown, according to equations (6) and (7), the basic heat load of each heat user is corrected to the actual heat load.

[0130] Where ε is the heat load correction factor, t i The indoor temperature is 21℃; t o The outdoor temperature is 0℃; t a It is the real-time outdoor temperature, which is the weather temperature.

[0131] After correction according to the temperature, the actual heat load of each heat user per hour is shown in Table 3.

[0132] Table 3 Actual heat load per hour for each heat user in the heat network (unit: MW)

[0133]

[0134]

[0135] Step 6: Calculate the heating steam extraction capacity of the condensing unit after adjustment.

[0136] Step 6-1: Obtain the data on the electric load and heating steam extraction volume of the condensing unit over a period of time.

[0137] Step 6-2: Adjust the space according to the thermal and electrical load of the unit to obtain the maximum electrical load P that the unit can reach under the current heating and extraction steam capacity. max With minimum electrical load P min .

[0138] Step 6-3: Set the target load P OB With P max and P min Compare.

[0139] The actual power load, target power load, and heating steam extraction data of the condensing unit in one day are as follows: Figure 8 The following steps are taken for each hour of data:

[0140] If P OB In P max With P min There is no need to adopt the heat network coordination method, and the target power load can be achieved by relying on the unit's own adjustment ability.

[0141] If P OB >P max , then it is necessary to coordinate the heat network regulation, and the power generation power required to be increased is P OB -P max , then the heating extraction steam volume after adjustment of the collaborative heating network is calculated by formula (8).

[0142] If P OB <P min , then it is necessary to coordinate the heat network regulation, and the power generation power that needs to be reduced is P min -P OB , then the heating extraction volume after adjustment of the collaborative heating network is calculated by formula (9).

[0143] Step 6-4: Substitute the adjusted heat extraction steam volume of the cooperative heat network into the heat network equivalent mathematical model mentioned in step 3, and calculate the indoor temperature change curve of each heat user by formula (10). Assume that the initial indoor temperature of each heat user is 21°C.

[0144] If the indoor temperature of the heat user is always between 16℃ and 24℃ as required by the Indoor Air Quality Standard (GB / T 18883-2022), the output m H ; If the maximum or minimum value of the indoor temperature of the heat user exceeds the required range, m H Gradually reduce, perform iterative calculation until the indoor temperature of the heat user always meets the range of 16℃~24℃, and output m H .

[0145] Step 6-5: According to the output m H , recalculate the power generation of the condensing unit and output it as the result of iterative calculation.

[0146] Before and after the adjustment of the coordinated heating network, the hourly heating steam extraction volume of the condensing unit is m H The power generation capacity is shown in Table 4. From the data in the table, it can be seen that the power generation capacity of the unit is completely consistent with the target power load, which proves the feasibility of the extraction condensing unit to coordinate the heat network for flexible peak regulation.

[0147] Before and after the coordinated heating network, the thermal power load data of the condensing unit is as follows: Fig. 9As shown in the figure, the coordinated heat network adjustment can make the unit's operating condition point break through the original thermal power load adjustment space limit, thereby improving the unit's flexible peak-shaving capacity.

[0148] During the coordinated heating network adjustment period, the indoor temperature of all heating users changes as follows: Fig.10 As shown, it meets the 16℃~24℃ range required by the "Indoor Air Quality Standard" (GB / T 18883-2022).

[0149] Table 4 Heating steam extraction capacity and power generation of condensing units before and after the coordinated heating network

[0150]

[0151]

[0152] In view of the deficiencies in the existing technologies and operation strategies, this embodiment provides a flexible peak-shaving method for the coordinated use of extraction condensing units and the heat network, thereby achieving flexible peak-shaving of the extraction condensing units while ensuring the thermal user experience and complying with national heating standards.

[0153] Embodiment 2

[0154] This embodiment provides a peak load regulation system for a heat network coordinated with an extraction condensing unit, comprising:

[0155] A heat network model building module is configured to obtain a thermal power load adjustment diagram space of the extraction and condensing units and build an equivalent mathematical model of the heat network;

[0156] The limiting calculation module is configured to obtain the electric load and heating steam extraction data of the condensing unit over a period of time, and obtain the maximum and minimum electric loads that the unit can reach under the current heating steam extraction according to the thermal and electric load adjustment space of the condensing unit;

[0157] The coordinated peak-shaving module is configured to determine the coordinated peak-shaving mode of the heat network and calculate the corresponding adjusted heating extraction volume by comparing the target electric load with the maximum electric load and the minimum electric load;

[0158] The heating extraction volume determination module is configured to substitute the adjusted heating extraction volume into the equivalent mathematical model of the heating network, calculate the indoor temperature change curve of each heat user, and if the indoor temperature of the heat user exceeds the indoor standard, the adjusted heating volume will be reduced for iterative calculation until the indoor temperature of the heat user always meets the indoor standard, and output the final heating extraction volume and the corresponding power generation power of the condensing unit.

[0159] The examples and application scenarios implemented by the above modules and corresponding steps are the same, but are not limited to the contents disclosed in the above embodiment 1. It should be noted that the above modules as part of the system can be executed in a computer system such as a set of computer executable instructions.

[0160] The description of each embodiment in the above embodiments has different emphases. For parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0161] The proposed system can be implemented in other ways. For example, the system embodiment described above is only illustrative, and the division of the modules is only a logical function division. In actual implementation, there may be other division methods, such as multiple modules can be combined or integrated into another system, or some features can be ignored or not executed.

[0162] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A method for peak load regulation of heat network coordinated by extraction condensing units. It is characterized in that include: Obtain the thermal and electric load adjustment diagram space of the extraction and condensing units and construct an equivalent mathematical model of the heat network; Obtain the data of the electric load and heating steam extraction volume of the condensing unit over a period of time, and adjust the thermal and electric load of the condensing unit to obtain the maximum and minimum electric loads that the condensing unit can reach under the current heating steam extraction volume; By comparing the target electric load with the maximum electric load and the minimum electric load, the peak load regulation mode of the collaborative heating network is determined and the corresponding adjusted heating extraction volume is calculated; The adjusted heating extraction volume is substituted into the equivalent mathematical model of the heating network to calculate the indoor temperature change curve of each heat user. If the indoor temperature of the heat user exceeds the indoor standard, the adjusted heating volume will be reduced for iterative calculation until the indoor temperature of the heat user always meets the indoor standard, and the final heating extraction volume and the corresponding power generation power of the condensing unit are output.

2. A method for peak load regulation of a heat network coordinated with a condensing unit as claimed in claim 1, It is characterized in that The method of obtaining the thermal power load adjustment diagram space of the extraction condensing unit and constructing the equivalent mathematical model of the heat network is specifically as follows: Obtain the thermal and electric load adjustment diagram space of the condensing unit, and calculate the delay time from the change in the heating steam extraction volume to the heat user's perception of the indoor temperature change; According to the specific distribution of heat users along the heat network pipeline, a heat network schematic diagram is formed, and the heat network schematic diagram is simplified using the node method to obtain a simplified heat network model; Calculate the basic heat load of each heat user according to the building type, heating area and whether energy-saving measures are adopted; Obtain local weather data, and use the weather data to correct the basic heat load of heat users to obtain the corrected basic heat load; Based on the corrected basic heat load and the simplified heating network model, the equivalent mathematical model of the heating network is obtained.

3. A method for peak load regulation of a heat network coordinated with an extraction condensing unit as claimed in claim 2, It is characterized in that The delay time from when the amount of steam extraction for heating changes to when the heat user begins to perceive the change in indoor temperature is composed of two parts of delay: the primary network and the secondary network. The primary network considers the primary network pipeline temperature transmission delay time and primary network pipeline temperature loss; The secondary network takes into account the time delay caused by the heat exchange process in the heat exchange station located between the primary network and the secondary network.

4. A method for peak load regulation of a heat network coordinated with an extraction condensing unit as claimed in claim 3, It is characterized in that The primary network pipeline temperature transmission delay time is obtained by multiplying the primary network heat delay coefficient and the primary network pipeline length by the primary network heat medium flow rate; The primary network pipeline temperature loss is determined based on the difference between the primary heat network pipeline starting temperature and the ambient temperature, the total heat transfer coefficient of the pipeline per unit length, the constant pressure specific heat capacity of water, and the primary network heat medium flow rate.

5. A method for peak load regulation of a heat network coordinated with an extraction condensing unit as claimed in claim 3, It is characterized in that The time delay caused by the heat exchange process of the heat exchange station between the primary network and the secondary network is to obtain the dynamic response curve of the heat exchange station connecting the primary network and the secondary network, and its dynamic characteristics are approximated as an inertia delay transfer function with a time constant as , so as to characterize the change law of the secondary network temperature after the heat of the primary network changes.

6. A method for peak load regulation of a heat network coordinated by an extraction condensing unit as claimed in claim 2, It is characterized in that The basic heat load of each heat user is calculated according to the building type, heating area and whether energy-saving measures are adopted by the heat user, specifically: Determine the comprehensive heating index based on the building type of the heat user and whether energy-saving measures are adopted; The basic heat load of each heat user is determined by the product of the comprehensive heating index and the heating area of ​​the heat user.

7. A method for peak load regulation of a heat network coordinated with an extraction condensing unit as claimed in claim 2, It is characterized in that The local weather data is obtained, and the basic heat load of the heat user is corrected using the weather data to obtain the corrected basic heat load, specifically: Determine the heat load correction factor based on the indoor calculated temperature, outdoor calculated temperature and outdoor real-time temperature; The corrected basic heat load is determined by multiplying the heat load correction coefficient by the basic heat load of each heat user.

8. A method for peak load regulation of a heat network coordinated with an extraction condensing unit as claimed in claim 1, It is characterized in that By comparing the target electric load with the maximum electric load and the minimum electric load, the method of coordinated heating network peak regulation is determined and the corresponding adjusted heating extraction volume is calculated, specifically: If the target power load is between the maximum power load and the minimum power load, there is no need to adopt the heat network coordination method, and the target power load can be achieved by relying on the adjustment ability of the condensing unit itself; If the target electric load is greater than the maximum electric load, it is necessary to coordinate with the heat network to adjust, and use the difference between the two as the increased power generation power, and subtract the heat supply and extraction steam volume of the condensing unit from the quotient of the increased power generation power and the thermoelectric conversion coefficient to obtain the adjusted heat supply and extraction steam volume; If the target electric load is less than the minimum electric load, the heating network conditions must be coordinated, and the difference between the two is used as the reduced power generation power. The heat extraction volume of the condensing unit is summed with the quotient of the reduced power generation power and the electric heat conversion coefficient to obtain the adjusted heat extraction volume.

9. A method for peak load regulation of a heat network coordinated with an extraction condensing unit as claimed in claim 1, It is characterized in that Substituting the adjusted heat extraction steam volume into the heat network equivalent mathematical model mentioned in step 3, the indoor temperature change curve of each heat user is calculated, specifically: Where M b is the weight of the heat user's building, in kg; c b is the specific heat capacity of the heat user building, in kJ / (kg·℃); Q in and Q out They are respectively the heat entering the heat user's building through the secondary network water supply pipeline per unit time and the heat dissipated by the heat user's building, both in MW.

10. A peak load regulation system of a condensing unit and a heat network. It is characterized in that include: A heat network model building module is configured to obtain a thermal power load adjustment diagram space of the extraction and condensing units and build an equivalent mathematical model of the heat network; The limiting calculation module is configured to obtain the electric load and heating steam extraction data of the condensing unit over a period of time, and obtain the maximum and minimum electric loads that the unit can reach under the current heating steam extraction according to the thermal and electric load adjustment space of the condensing unit; The coordinated peak-shaving module is configured to determine the coordinated peak-shaving mode of the heat network and calculate the corresponding adjusted heating extraction volume by comparing the target electric load with the maximum electric load and the minimum electric load; The heating extraction volume determination module is configured to substitute the adjusted heating extraction volume into the equivalent mathematical model of the heating network, calculate the indoor temperature change curve of each heat user, and if the indoor temperature of the heat user exceeds the indoor standard, the adjusted heating volume will be reduced for iterative calculation until the indoor temperature of the heat user always meets the indoor standard, and output the final heating extraction volume and the corresponding power generation power of the condensing unit.

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