A method and device for collaborative optimization scheduling of boiler and network for cogeneration of regional heating

Abstract

The present invention discloses a method and device for collaborative optimization scheduling of boilers, turbines and networks for cogeneration of regional heating. The method obtains the total amount of boiler load adjustment by real-time tracking changes in heat network user sub-meter flow, turbine back pressure, large user pressure, end-user pressure and the sum of large user flow, and calculates the collaborative optimization scheduling parameters of the boiler, turbine and desuperheater based on this. On this basis, the collaborative optimization scheduling parameters are assigned to the corresponding control parameters of the boiler APC, turbine DEH and desuperheater, realizing automatic judgment, adjustment and control of the system, and quickly responding to changes in heat network user load, thereby ensuring the smooth operation of the steam supply network pressure, reducing the labor intensity of operators, and saving energy and reducing carbon emissions.

Description

Technical Field

[0001] The present invention relates to the field of load follow-up scheduling of cogeneration regional heating, and in particular to a method and device for collaborative optimization scheduling of boilers and networks in cogeneration regional heating. Background Art

[0002] Cogeneration is a technology that produces both electricity and heat from a single primary energy source. Compared to traditional methods of generating heat and electricity separately, cogeneration utilizes the generated gas / steam as heat, achieving cascaded energy utilization and improving energy efficiency, thereby reducing costs and carbon emissions.

[0003] Cogeneration companies for regional heating primarily provide heat, supplemented by power generation, with electricity determined by heat. They have distinct characteristics: a large number of heat users, scattered geographical distribution, a wide heating range, long pipeline networks, and intermittent and non-periodic steam loads. Steam supply data and steam user data are independent and scattered, and cannot be centrally monitored and used. The mismatch between the heating load and the steam load leads to the intermittent use of desuperheaters and pressure reducers. When the steam load of heat users fluctuates drastically and frequently, boiler and steam turbine operators at the steam supply end need to keep a close eye on the dynamic changes in the steam load of heat users. Due to the imbalance between steam supply and demand and the long pipeline transmission distance, the operators' labor intensity is high, and it is difficult for operational adjustments to respond quickly to changes. There are problems with over-adjustment and lagging adjustment, which leads to pressure fluctuations in the steam supply network and steam supply quality that cannot meet user requirements.

[0004] Patent CN102242868B discloses a method for optimizing the operation of steam networks in industrial plants. This method, based on a mathematical model of steam network operating costs, considers various constraints in actual industrial processes, uses turbine steam intake and extraction rates, and pump-turbine availability as operational variables, and utilizes a collaborative quantum particle optimization algorithm to optimize process operating conditions to reduce steam network operating costs. This optimization method provides a foundation and basis for production process improvements, but it fails to consider the impact of random fluctuations in industrial plant load on steam network pressure stability.

[0005] Patent CN111503718B discloses a combined heat and power (CHP) heating load forecasting method and heating system based on multiple factors. By comprehensively considering factors such as meteorological parameters, pipeline network characteristics, and building properties, this method establishes a long-term heat load forecast model for a specific day in the future and a short-term heat load forecast model for real-time heat load regulation. This method predicts both expected future and short-term heat load demands, but fails to achieve coordinated control with boiler APC and turbine DEH. Its primary application is residential heating, and it is unsuitable for industrial steam use in district heating. Summary of the Invention

[0006] In order to solve the problem that cogeneration enterprises of regional heating face frequent fluctuations in steam load of heat users, the adjustment of boilers and steam turbines at the steam supply end is difficult to respond quickly, resulting in pipeline pressure fluctuations and the quality of steam supply cannot meet user needs, the present invention provides a boiler-turbine-network collaborative optimization scheduling method and device for cogeneration regional heating. The total amount of boiler load adjustment is obtained by real-time tracking the changes in the flow of heat network user sub-meters, steam turbine back pressure, large user pressure, end-user pressure and the sum of large user flow, and the collaborative optimization scheduling parameters of boilers, steam turbines and desuperheater are calculated based on this. On this basis, the collaborative optimization scheduling parameters are assigned to the corresponding control parameters of boiler APC and steam turbine DEH, realizing automatic judgment, adjustment and control of the system, and quickly responding to changes in heat network user load, thereby ensuring the smooth operation of steam supply pipeline pressure, reducing the labor intensity of operators, and saving energy and reducing carbon.

[0007] The technical solution adopted by the present invention to overcome its technical problems is: the first aspect of the present invention proposes a method for collaborative optimization scheduling of boiler and machine network for cogeneration regional heating, which is characterized by comprising the following steps: S1, collecting the operating data of the boiler, the operating data of the steam turbine, the operating data of the temperature reducer and the pressure reducer, and the user data of the heat network in the distributed control system and storing them in a real-time database, and performing data preprocessing and mean filtering on the stored data to obtain a valid data set; S2, establishing a collaborative optimization scheduling model for the boiler and machine network based on the obtained valid data set, solving it within the range of the device constraints to obtain the total amount of boiler load adjustment, and based on the boiler load adjustment, The total amount of boiler load adjustment is calculated to obtain the boiler load set value, boiler main steam pressure set value, turbine main steam pressure set value, turbine power set value, and desuperheater load set value; S3, based on the obtained boiler load set value and boiler main steam pressure set value, the boiler APC load and the boiler APC main steam pressure target value are optimized; S4, a turbine delay execution model is established, and based on the obtained turbine main steam pressure set value and turbine power set value, and desuperheater load set value, the turbine DEH main steam pressure value and turbine power target value, as well as the desuperheater load target value, are optimized according to whether the boiler load adjustment is completed.

[0008] Furthermore, the boiler operation data includes at least: boiler main gas flow, boiler main steam pressure, bed temperature, boiler APC load target value, boiler APC main steam pressure target value, coal feeder manual status, boiler APC communication status, boiler APC one-button cut-off status, boiler APC pressure regulation mode status; the steam turbine operation data includes at least: steam turbine inlet flow, steam turbine back pressure, steam turbine extraction flow, steam turbine exhaust flow, steam turbine power generation, steam turbine main steam pressure target value, steam turbine power target value, steam turbine pressure regulation mode status, steam turbine power mode status, steam turbine manual mode status; the desuperheater and pressure reducer operation data includes at least: desuperheater and pressure reducer inlet flow, pressure and temperature; desuperheater and pressure reducer outlet pressure and temperature; desuperheater water flow, pressure and temperature; desuperheater and pressure reducer pressure regulating valve opening target value, temperature regulating valve opening target value; the heating network user data includes at least: user sub-meter flow, large user flow, large user pressure, end user flow, end user pressure.

[0009] Furthermore, the boiler-machine network collaborative optimization scheduling model at least includes a steam turbine exhaust pressure sub-model, a boiler load adjustment total sub-model, a boiler double reduction adjustment sub-model, a steam turbine adjustment sub-model and a boiler adjustment sub-model; the boiler-machine network collaborative optimization scheduling model is divided into a fast process and a slow process for calculating the boiler load adjustment total. In the slow process, the boiler load adjustment total includes the contribution of the change in the flow rate of the heat network user sub-meter to the boiler load adjustment total, the contribution of the change in the steam turbine back pressure to the boiler load adjustment total, the contribution of the large user pressure to the boiler load adjustment total and the contribution of the end user pressure to the boiler load adjustment total; in the fast process, the boiler load adjustment total includes the contribution of the change in the sum of the large user flow rates to the boiler load adjustment total; the system adjustment speed is carried out according to the adjustment flags 0, 1 and 2. When the adjustment flag is 0, the slow process is carried out, and when the adjustment flags are 1 and 2, the fast process is carried out. After execution, the adjustment flag is increased by 1, and when the adjustment flag is less than 0 or greater than 2, it is reset to 0.

[0010] Furthermore, the steam turbine exhaust pressure sub-model is used to determine whether the current steam turbine is running and to determine the reference value of the main steam pressure setting value and the reference value of the power setting value of each steam turbine; when the steam turbine speed is greater than 2990r / min and the power generation capacity is greater than 5MW, the steam turbine is considered to be in operation, and the reference value of the steam turbine main steam pressure and power setting value is the current steam turbine main steam pressure and power target value.

[0011] Furthermore, the total boiler load adjustment sub-model is used to calculate the total boiler load adjustment according to the load change of the heating network users, and is calculated according to formula (1):

[0012] ΔQ=q fb +q by +q dhpre +q mdpre +qdhflow (1)

[0013] Where, ΔQ is the total amount of boiler load adjustment, t / h; q fb The contribution of the flow change of the heat network user's meter to the total boiler load adjustment, in t / h; q by The contribution of turbine back pressure change to the total boiler load adjustment, in t / h; q dhpre The contribution of large user pressure to the total boiler load adjustment, in t / h; q mdpre The contribution of the end-user pressure to the total boiler load adjustment, in t / h; q dhflow It is the contribution of the sum of large user flows to the total boiler load adjustment, in t / h.

[0014] Furthermore, the contribution of the heat network user sub-meter flow change to the total boiler load adjustment is q fb Calculate according to formula (2):

[0015] q fb =k fb ·(fb ave(t) -fb ave(t-1) ) (2)

[0016] Where q fb The contribution of the flow change of the heat network user's meter to the total boiler load adjustment, in t / h; k fb The flow adjustment coefficient of the heat network user sub-meter; fb ave（t） fb is the average flow rate of the heating network users at the current moment, in t / h; ave（t-1） The average flow rate of each heat network user at the previous moment, in t / h;

[0017] The contribution of the turbine back pressure change to the total boiler load adjustment is q by Calculate according to formula (3):

[0018] q by =k by ·(Δby ave(t) +(SUMΔby bve ) (t-1) (3)

[0019] Where q by The contribution of turbine back pressure change to the total boiler load adjustment, in t / h; k by is the adjustment coefficient of the cumulative value of the turbine back pressure change rate; Δby ave(t) The turbine back pressure change rate is the ratio of the turbine back pressure change to time, and the unit is MPa / min; (SUM Δbybve )(t-1) It is the cumulative value of the turbine back pressure change rate at the previous moment, in MPa / min.

[0020] The contribution of the large user pressure to the total boiler load adjustment q dhpre Calculate according to formula (4):

[0021] q dhpreq =k dhpre Q dhpre (4)

[0022] Where q dhpre The contribution of large user pressure to the total boiler load adjustment, in t / h; k dhpre Q is the pressure adjustment coefficient for large users; dhpre To meet the pressure of large users, adjust the boiler load in t / h;

[0023] The contribution of the end-user pressure to the total boiler load adjustment q mdpre Calculate according to formula (5):

[0024] q mdpre =k mdpre Q mdpre (5)

[0025] Where q mdpre The contribution of the end-user pressure to the total boiler load adjustment, in t / h; k mdpre is the end-user pressure adjustment coefficient; Q mdpre To meet the end user pressure to boiler load adjustment, the unit is t / h; the contribution of the sum of the large user flow changes to the total boiler load adjustment q dhflow Calculate according to formula (6):

[0026] q dhflow =k dhflow ·(dhflow ave(t) -dhflow ave(t-1) ) (6)

[0027] Where q dhflow The contribution of large user flow to the total boiler load adjustment, in t / h; k dhflow dhflow is the large user flow adjustment coefficient; ave(t) is the sum average of the current large user traffic, in t / h; fb ave(t-1) It is the average sum of large user traffic at the previous moment, in t / h.

[0028] Furthermore, the boiler double reduction adjustment sub-model is used to calculate the boiler load adjustment amount based on formula (1) and the boiler main steam pressure setting value according to formula (7).

[0029] Pre glset =k pregl ΔQ+Pre glgoal (7)

[0030] Where, Pre glset is the boiler main steam pressure setting value, unit is MPa; k pregl is the boiler main steam pressure variation coefficient; ΔQ is the total amount of boiler load adjustment; Pre glgoal The boiler main steam pressure reference value is the boiler APC main steam pressure target value when the boiler APC is in operation, and the maximum main steam pressure of all boilers when not in operation, in MPa.

[0031] Furthermore, the turbine adjustment sub-model is used to calculate the turbine main steam pressure setting value according to formula (8) based on the total boiler load adjustment amount calculated by formula (1), and to calculate the turbine power setting value according to formula (9).

[0032]

[0033] Power qjset =a+b·(x+ΔQ) (9)

[0034] Where, Pre qjset is the set value of the main steam pressure of the steam turbine, in MPa; Pre qjgoal is the target value of the main steam pressure of the steam turbine, in MPa; is the change in the main steam pressure of the steam turbine, in MPa; k preqj The adjustment step of the main steam pressure of the steam turbine, in MPa; is the number of times the main steam pressure of the steam turbine is adjusted; ΔQ is the total amount of boiler load adjustment, in t / h; α is the characteristic factor of the main steam pressure adjustment of the steam turbine, Power qjest is the turbine power setting value, in MW; a is the turbine model constant; b is the turbine model coefficient; x is the turbine main steam flow, in t / h.

[0035] Furthermore, the boiler adjustment sub-model is used to determine the load setting value of each boiler based on the total amount of boiler load adjustment calculated by formula (1), wherein the allocation steps are as follows: S21, determining the number of boilers in operation according to the boiler main steam flow rate; S22, judging the boiler APC operation state according to the manual state of the boiler coal feeder, and determining whether the boiler APC is in the pressure adjustment mode or the load adjustment mode according to the boiler APC pressure adjustment mode state; S23, if the boiler APC is in operation and in the pressure adjustment mode, then calculating the boiler main steam pressure setting value according to formula (7); if the boiler APC is in operation and in the load adjustment mode, then calculating the boiler load setting value according to formula (10):

[0036]

[0037] Where Q glset(i) is the boiler load setting value, t / h; Q glbase(i) is the boiler i load reference value, in t / h; ΔQ is the total boiler load adjustment amount, in t / h; m1 is the threshold value when increasing the boiler load; m2 is the threshold value when reducing the boiler load; Q total It is the total steam production of all boilers, in t / h. F is the total steam production threshold of boilers. is the weight of boiler i’s steam production in the total steam production of boilers.

[0038] Furthermore, the boiler bed temperature and the boiler main steam pressure change rate are calculated based on the turbine delay execution model, and whether the boiler load adjustment is completed is determined according to formula (11):

[0039]

[0040] Where DelayDone is the status of the steam turbine delay execution completion; ΔCWJz is the average temperature change rate of the boiler bed layer i, which is the ratio of the average temperature change of the bed layer to time. The average bed temperature is obtained from the real-time database and the unit is ℃ / min; is the threshold value of the average temperature change rate of boiler bed i, in °C / min; is the main steam pressure change rate of boiler i, which is the ratio of the main steam pressure change to time, and the unit is MPa / min; is the main steam pressure change rate threshold of boiler i, in MPa / min.

[0041] After the boiler load adjustment is completed, the turbine main steam pressure setting value obtained by formula (8) and the turbine power setting value obtained by formula (9) are assigned to the corresponding target value of the turbine DEH according to the current mode state of the turbine. The target value includes the turbine main steam pressure setting value and the turbine power setting value. Among them, if the turbine is in the main steam pressure mode, the turbine main steam pressure setting value is assigned to the turbine DEH main steam pressure value; if the turbine is in the power mode, the turbine power setting value is assigned to the turbine DEH power value; if the turbine is in the manual mode, no value is assigned; if the turbine is in the full load state, the total amount of boiler load adjustment is assigned to the desuperheater load setting value.

[0042] Furthermore, it also includes a disturbance-free switching safety mechanism for realizing the switching between collaborative optimization mode and manual operation mode, specifically including: collaborative optimization commissioning of the boiler-machine network; collaborative optimization removal of the boiler-machine network; disturbance-free switching between collaborative optimization mode and manual operation mode. When any of the above processes is performed, a pop-up window will be displayed for confirmation and sound and color alarms will be issued.

[0043] Furthermore, the collaborative optimization mode and the manual operation mode are switched without disturbance, specifically including: when the system is put into operation, the boiler APC target value and the steam turbine DEH target value are equal to the boiler-turbine-network collaborative optimization set value; when the system is cut off, the boiler-turbine-network collaborative optimization set value, the boiler APC target value and the steam turbine DEH target value are equal to the current real-time value of the system.

[0044] Furthermore, the collaborative optimization mode includes a boiler-machine-network collaborative optimization commissioning mode and a boiler-machine-network collaborative optimization cutoff mode, specifically including: based on the boiler-machine-network collaborative optimization communication status, the boiler-machine-network collaborative optimization one-button cutoff, the boiler coal feeder manual status, the boiler APC commissioning status, the boiler APC pressure regulation mode status, the steam turbine delayed execution completion status, the steam turbine main steam pressure mode and the steam turbine adjustable status, the boiler-machine-network collaborative optimization commissioning mode is realized; based on the boiler-machine-network collaborative optimization communication status, the boiler coal feeder manual status, the boiler APC communication status, the boiler APC one-button cutoff status, the boiler-machine-network collaborative optimization one-button cutoff status, the boiler load commissioning status, the boiler pressure commissioning status, the steam turbine main steam pressure commissioning status and the automobile power commissioning status, the boiler-machine-network collaborative optimization cutoff mode is realized.

[0045] The second aspect of the present invention proposes a collaborative optimization scheduling device for a boiler-machine network for cogeneration regional heating, which is used to run the above-mentioned collaborative optimization scheduling method for a boiler-machine network for cogeneration regional heating. The collaborative optimization scheduling device for the boiler-machine network includes: a data processing module, which is used to collect the operating data of the boiler, the operating data of the steam turbine, the operating data of the attemperator and pressure reducer, and the user data of the heat network in the distributed control system and store them in a real-time database, and pre-process and mean filter the stored data to obtain a valid data set; a collaborative optimization scheduling module, which is used to solve within the range of device constraints to obtain the total amount of boiler load adjustment, and based on the total amount of boiler load adjustment, respectively calculate the boiler load setting value, the boiler main steam pressure setting value, the steam turbine main steam pressure setting value, the steam turbine power setting value, and the attemperator and pressure reducer load setting value; a steam turbine delay execution module, which is used to determine whether the boiler load adjustment is completed and output a steam turbine adjustment instruction; a collaborative optimization control module, which is used to determine whether the collaborative optimization of the boiler-machine network is effective according to the system status, and assign the scheduling optimization setting value to the boiler APC target value and the steam turbine DEH target value to perform optimization control.

[0046] The beneficial effects of the present invention are:

[0047] 1. When the steam load of heat users is frequently adjusted, the heat network load is used as a feedforward signal to adjust the boiler load in advance, and the steam turbine is operated in conjunction to achieve coordinated optimization of the boiler, steam turbine and heat network.

[0048] 2. By assigning collaborative optimization scheduling parameters to the corresponding control parameters of the boiler APC and steam turbine DEH, the system can automatically judge, adjust and control, quickly respond to changes in the heat network user load, thereby ensuring the smooth operation of the steam supply network pressure, reducing the labor intensity of operators, and saving energy and reducing carbon emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is a flow chart of a method for collaborative optimization scheduling of boilers and networks for cogeneration of heat and power district heating proposed in this application;

[0050] Figure 2 This is a schematic diagram of a boiler-machine-network collaborative optimization scheduling device for cogeneration district heating proposed in this application;

[0051] Figure 3 This is a schematic diagram of the boiler-machine network collaborative optimization scheduling process for a combined heat and power district heating system proposed in this application;

[0052] Figure 4 This is a comparison chart of boiler-machine network collaborative optimization and manual operation during the period when the system was not put into operation;

[0053] Figure 5 This is a comparison chart of the steam supply main pipe pressure curve before and after the boiler-machine network collaborative optimization scheduling is put into operation. DETAILED DESCRIPTION

[0054] To facilitate understanding by those skilled in the art, some of the technical aspects of the present invention are first described as follows:

[0055] DCS: distributed control system;

[0056] Boiler and machine network: boiler, steam turbine and heat network;

[0057] Mean filtering: Mean filtering is a typical linear filtering algorithm that uses the mean of the data in the time window to replace the original value;

[0058] APC: Advanced Process Control;

[0059] DEH: Steam turbine digital electro-hydraulic control system.

[0060] In order to facilitate those skilled in the art to better understand the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. The following is only exemplary and does not limit the scope of protection of the present invention.

[0061] Example 1

[0062] In order to solve the problem that the heat and power cogeneration enterprises of regional heating face frequent fluctuations in the steam load of heat users, the adjustment of the boilers and steam turbines at the steam supply end is difficult to respond quickly, resulting in fluctuations in the pipe network pressure and the inability of the steam supply quality to meet user needs, the present invention provides a method for coordinated optimization scheduling of boilers and turbines in regional heating of cogeneration. Figure 1 As shown, the boiler-machine-network coordinated optimization scheduling method for cogeneration district heating includes:

[0063] Step 1: Collect the operating data of boilers, steam turbines, and desuperheaters in the DCS, as well as the heat network user data, store them in a real-time database, and perform data preprocessing and mean filtering to obtain a valid data set;

[0064] Step 2: Based on the obtained valid data set, a boiler-turbine network collaborative optimization scheduling model is established. Within the constraints of the equipment, the total boiler load adjustment is solved and used to calculate the boiler load and main steam pressure setpoints, the turbine main steam pressure and power setpoints, and the desuperheater and pressure reducer load setpoints.

[0065] Step 3: Optimize the boiler APC load and main steam pressure target values ​​based on the obtained boiler load and main steam pressure set values;

[0066] Step 4: Establish a steam turbine delayed execution model. Based on the obtained steam turbine main steam pressure and power set values ​​and the desuperheater load set value, optimize the steam turbine DEH main steam pressure and power target values ​​and the desuperheater load target value according to whether the boiler load adjustment is completed.

[0067] In an embodiment, the boiler operation data includes: boiler main gas flow, boiler main steam pressure, bed temperature, boiler APC load target value, boiler APC main steam pressure target value, coal feeder manual status, boiler APC communication status, boiler APC one-button cut-off status, and boiler APC pressure regulation mode status.

[0068] The steam turbine operation data includes: steam turbine inlet flow, steam turbine back pressure, steam turbine extraction flow, steam turbine exhaust flow, steam turbine power generation, steam turbine main steam pressure target value, steam turbine power target value, steam turbine pressure regulation mode status, steam turbine power mode status, and steam turbine manual mode status.

[0069] The desuperheater and pressure reducer operating data include: desuperheater and pressure reducer inlet flow, pressure and temperature; desuperheater and pressure reducer outlet pressure and temperature; desuperheater water flow, pressure and temperature; desuperheater and pressure reducer pressure regulating valve opening target value and temperature regulating valve opening target value.

[0070] The heating network user data includes: user meter flow, large user flow, large user pressure, end user flow, and end user pressure.

[0071] During the implementation process, data needs to be preprocessed and mean filtered. Preprocessing includes removing bad points and outliers. Mean filtering obtains a batch of data through a sliding time window. The mean of the batch of data is calculated based on the data in the sliding time window as the valid data of the parameter at the current moment, as shown in formula (1).

[0072]

[0073] In formula (1), N iave is the valid data after mean filtering; m is the number of data in the time window; t is the current time of the time window; tk is the start time of the time window; k is the length of the time window; N i is an unprocessed real-time value. In this embodiment, the time window length is 2 minutes.

[0074] The data that require mean filtering include the boiler main gas flow rate and bed temperature; the steam turbine inlet flow rate, steam turbine back pressure, steam turbine extraction flow rate, steam turbine exhaust flow rate, and steam turbine power generation; the desuperheater and pressure reducer inlet flow rate, pressure and temperature, the desuperheater and pressure reducer outlet pressure and temperature, the desuperheater water flow rate, pressure and temperature; the user sub-meter flow rate, large user flow rate, large user pressure, end-user flow rate, and end-user pressure.

[0075] The boiler-turbine-network collaborative optimization scheduling model is the core of this boiler-turbine-network collaborative optimization scheduling method, and is composed of a steam turbine backpressure sub-model, a boiler load adjustment total sub-model, a boiler double reduction adjustment sub-model, a steam turbine adjustment sub-model, and a boiler adjustment sub-model.

[0076] Preferably, the turbine backpressure submodel is used to determine which turbines are currently operating and, based on the currently operating turbines, to determine the reference values ​​for each turbine's main steam pressure and power settings. A turbine is considered operating when its speed is greater than 2990 r / min and its power generation is greater than 5 MW. The reference values ​​for the turbine's main steam pressure and power settings are the current turbine's target main steam pressure and power.

[0077] Preferably, the total boiler load adjustment sub-model is used to calculate the total boiler load adjustment according to the change of the heat network user load, and is calculated according to formula (2):

[0078] ΔQ=q fb +q by +q dhpre +q mdpre +q dhflow (2)

[0079] Where ΔQ is the total amount of boiler load adjustment, in t / h; q fb The contribution of the flow change of the heat network user's meter to the total boiler load adjustment, in t / h; q by The contribution of turbine back pressure change to the total boiler load adjustment, in t / h; q dhpre The contribution of large user pressure to the total boiler load adjustment, in t / h; q mdpre The contribution of the end-user pressure to the total boiler load adjustment, in t / h; q dhflow It is the contribution of the sum of large user flows to the total boiler load adjustment, in t / h.

[0080] The boiler-turbine-network coordinated dispatch optimization submodel operates in a fast and slow process, used to calculate the total boiler load adjustment. In the slow process, the total boiler load adjustment includes the contribution of changes in heat network user sub-meter flow, changes in steam turbine back pressure, large user pressure, and end-user pressure.

[0081] During the fast process, the total boiler load adjustment includes the contribution of changes in the sum of large user flows to the total boiler load adjustment. The speed of system adjustment is determined by the adjustment flags 0, 1, and 2. When the adjustment flag is 0, the slow process is executed; when the adjustment flags are 1 or 2, the fast process is executed. After execution, the adjustment flag is incremented by 1. If the adjustment flag is less than 0 or greater than 2, it is reset to 0. The system operating frequency has a significant impact on rapid response to fluctuations in steam load among heating network users. Different cogeneration systems have different effective operating frequencies. In this case, the operating frequency is 2 minutes, which aligns with the time window length.

[0082] The contribution of the heat network user sub-meter flow change to the total boiler load adjustment q fb Calculate according to formula (3):

[0083] q rb =k fb ·(fb ave(t) -fb ave(t-1) ) (3)

[0084] Where q fb The contribution of the flow change of the heat network user's meter to the total boiler load adjustment, in t / h; k fb The flow adjustment coefficient of the heat network user sub-meter; fb ave(t) fb is the average flow rate of the heating network users at the current moment, in t / h; ave(t-1) It is the average flow rate of heating network users at the previous moment, in t / h.

[0085] The contribution of the turbine back pressure change to the total boiler load adjustment is q by Calculate according to formula (4):

[0086] q by =k by ·(Δby ave(t) +(SUM Δbybve ) (t-1) ) (4)

[0087] Where q by is the contribution of turbine back pressure change to the total boiler load adjustment, t / h; k by is the adjustment coefficient of the cumulative value of the turbine back pressure change rate; Δby ave(t) is the rate of change of turbine back pressure, in MPa / min; (SUM Δbybve ) (t-1) It is the cumulative value of the turbine back pressure change rate at the previous moment, in MPa / min.

[0088] The contribution of the large user pressure to the total boiler load adjustment q dhpre Calculate according to formula (5):

[0089] q dhpre =k dhpre Q dhpre (5)

[0090] Where q dhpre The contribution of large user pressure to the total boiler load adjustment, in t / h; k dhpre Q is the pressure adjustment coefficient for large users; dhpre In order to meet the boiler load adjustment required by large user pressure, this value is an empirical value and the unit is t / h.

[0091] The contribution of the end-user pressure to the total boiler load adjustment q mdpre Calculate according to formula (6):

[0092] q mdpre =k mdpre Q mdpre (6)

[0093] Where q mdpre The contribution of the end-user pressure to the total boiler load adjustment, t / h; k mdpre is the end-user pressure adjustment coefficient; Q mdpre In order to meet the boiler load adjustment required by the end-user pressure, this value is an empirical value in t / h.

[0094] The contribution of the sum of the large user flows to the total boiler load adjustment is q dhflow Calculate according to formula (7):

[0095] q dhflow =k dhflow ·(dhflow ave(t) --dhflow ave(t-1) ) (7)

[0096] Where q dhflow is the contribution of large user flow to the total boiler load adjustment, t / h; k dhflow dhflow is the large user flow adjustment coefficient; ave(t) is the sum average of large user traffic at the current moment, t / h; fb ave(t-1) is the mean of the sum of large user traffic at the previous moment, t / h.

[0097] Preferably, the boiler double reduction adjustment sub-model is used to calculate the boiler main steam pressure setting value according to the calculated boiler load adjustment total amount according to formula (8):

[0098] Pre glset =k pregl ΔQ+Pre glgoal (8)

[0099] Where, Pre glset is the boiler main steam pressure setting value, unit is MPa; k pregl is the boiler main steam pressure variation coefficient; ΔQ is the total amount of boiler load adjustment; Pre glgoal This is the baseline value of the boiler's main steam pressure. When the boiler's APC is operational, this is the boiler's APC main steam pressure setpoint. When it is not operational, this is the maximum main steam pressure of all boilers. The unit is MPa. The maximum main steam pressure of a boiler is the main steam pressure of the boiler with the highest main steam pressure among all boilers.

[0100] Preferably, the turbine adjustment model is used to calculate the turbine main steam pressure setting value according to the obtained boiler load adjustment amount according to formula (9), and to calculate the turbine power setting value according to formula (10):

[0101]

[0102] Where, Pre qjset is the set value of the main steam pressure of the steam turbine, in MPa; Pre qjgoal is the target value of the main steam pressure of the steam turbine, in MPa; is the change in the main steam pressure of the steam turbine, in MPa; k preqj The adjustment step of the main steam pressure of the steam turbine, in MPa; is the number of turbine main steam pressure adjustments; ΔQ is the total amount of boiler load adjustment, in t / h; α is the turbine main steam pressure adjustment characteristic factor.

[0103] Power qjset =a+b·(x+ΔQ) (10)

[0104] Where Power qjest is the turbine power setting value, MW; a is the turbine model constant; b is the turbine model coefficient; x is the turbine main steam flow rate, corresponding to the turbine air intake volume, which is an instantaneous variable in t / h; ΔQ is the total boiler load adjustment in t / h.

[0105] Preferably, the boiler adjustment sub-model is used to determine the load setting value of each boiler according to the calculated total amount of boiler load adjustment. The allocation rules are as follows:

[0106] (1) First, the number of boilers in operation is determined based on the main steam flow rate of the boilers. The main steam flow rate of the boilers is obtained by the distributed control system into the real-time database and is an instantaneous variable.

[0107] (2) Determine which boilers are in operation based on the manual status of the boiler coal feeder and determine whether the boiler APC is in pressure regulation mode or load regulation mode based on the boiler APC pressure regulation mode status;

[0108] (3) If the boiler APC is in operation and in pressure adjustment mode, determine the boiler main steam pressure set value; if the boiler APC is in operation and in load adjustment mode, calculate the boiler load set value according to formula (11):

[0109]

[0110] Where Q glset(i) is the boiler load setting value, t / h; Q glbase(i)is the boiler i load reference value, which is an instantaneous variable and the unit is t / h; ΔQ is the total amount of boiler load adjustment and the unit is t / h; m1 is the threshold value when the boiler load is increased; m2 is the threshold value when the boiler load is reduced; Q total is the current total steam production of the boiler, in t / h; F is the total steam production threshold of the boiler; is the weight of boiler i’s steam production in the total steam production of boilers.

[0111] Preferably, the steam turbine delayed execution model calculates the boiler bed temperature and the boiler main steam pressure change rate, and determines whether the boiler load adjustment is completed according to formula (12):

[0112]

[0113] Where DelayDone is the steam turbine delay completion status; ΔCWJZ is the average bed temperature change rate of boiler i, which is the ratio of the bed temperature change to time. The bed temperature is obtained from the real-time database and the unit is ℃ / min. is the threshold value of the average temperature change rate of boiler bed i, in °C / min; is the main steam pressure change rate of boiler i, in MPa / min; is the main steam pressure change rate threshold of boiler i, in MPa / min.

[0114] The turbine delayed execution model also includes determining the turbine main steam pressure and power setpoints obtained after boiler load adjustment is completed and assigning them to the corresponding target values ​​of the turbine DEH according to the turbine's current mode. If the turbine is in main steam pressure mode, the turbine main steam pressure setpoint is assigned to the turbine DEH main steam pressure value; if the turbine is in power mode, the turbine power setpoint is assigned to the turbine DEH power value; if the turbine is in manual mode, no value is assigned; if the turbine is in full load, the total boiler load adjustment amount is assigned to the desuperheater load setpoint.

[0115] Preferably, the boiler-machine network collaborative optimization scheduling method further includes a non-disruptive switching safety mechanism for realizing switching between the collaborative optimization mode and the manual operation mode, including:

[0116] Boiler-machine network collaborative optimization and commissioning:

[0117] (1) Boiler load allows operation: The communication status of the boiler-machine network collaborative optimization is true, the one-key cutoff of the boiler-machine network collaborative optimization is false, the manual state of the boiler coal feeder is false, the boiler APC operation state is true, and the boiler APC pressure regulation mode state is false. When all the above conditions are met, the boiler is in the load adjustment operation state. The operator clicks the boiler load operation button to complete the operation of the boiler-machine network collaborative optimization, and the system automatically runs.

[0118] (2) Boiler pressure allows operation: The communication status of the boiler-machine network collaborative optimization is true, the one-key cutoff of the boiler-machine network collaborative optimization is false, the boiler coal feeder manual status multiple-choice two is false, the boiler APC operation status is true, and the boiler APC pressure regulation mode status is true. When all the above conditions are met, the boiler is in the pressure adjustment operation state. The operator clicks the boiler pressure operation button to complete the boiler-machine network collaborative optimization operation, and the system automatically runs.

[0119] (3) Turbine Main Steam Pressure Allowed Operation: The communication status of the boiler-turbine network collaborative optimization is true, the one-button cutoff of the boiler-turbine network collaborative optimization is false, the boiler coal feeder manual state multiple choice two is false, the boiler APC operation state is true, the turbine delayed execution completion state is true, the turbine main steam pressure mode is true, and the turbine adjustable state is true. When all the above conditions are met, the turbine is in the main steam pressure allowed operation state. The operator clicks the turbine main steam pressure operation button to complete the boiler-turbine network collaborative optimization operation, and the system automatically runs.

[0120] (4) Turbine power allowed to start operation: The communication status of the boiler-turbine network collaborative optimization is true, the one-key cutoff of the boiler-turbine network collaborative optimization is false, the boiler coal feeder manual state multiple choice two is false, the boiler APC start state is true, the steam turbine delayed execution completion state is true, the steam turbine power mode is true, and the steam turbine adjustable state is true. When all the above conditions are met, the steam turbine is in the power allowed to start operation state. The operator clicks the steam turbine power start button to complete the boiler-turbine network collaborative optimization start operation, and the system automatically runs.

[0121] Furnace-machine-network collaborative optimization removal:

[0122] (1) Automatic cutoff: The communication status of the boiler network collaborative optimization is false, the boiler coal feeder manual status multiple choice two is true, the boiler APC communication is normal is false, and the boiler APC one-key cutoff is true. If any of the above conditions are met, the system will automatically cut off.

[0123] (2) Manual cut-off: The one-key cut-off of boiler-machine network collaborative optimization is true, the boiler load operation is false, the boiler pressure operation is false, the steam turbine main steam pressure operation is false, and the steam turbine power operation is false. If any of the above conditions requires manual operation, the system will be manually cut off.

[0124] Disturbance-free switching between collaborative optimization mode and manual operation mode:

[0125] When the system is put into operation, the boiler APC target value and the steam turbine DEH target value are equal to the boiler-turbine-network collaborative optimization set value. When the system is shut down, the boiler-turbine-network collaborative optimization set value, the boiler APC target value and the steam turbine DEH target value are equal to the current real-time value of the system.

[0126] When any of the above processes is performed, a pop-up window will be displayed for confirmation and an audible and color alarm will be issued.

[0127] Example 2

[0128] This embodiment also proposes a device for cogeneration district heating boiler network coordinated optimization scheduling, specifically as follows: Figure 2 As shown, the boiler-machine network collaborative optimization scheduling device includes:

[0129] The data processing module 201 is used to collect the operating data of the boiler, the steam turbine, the desuperheater and pressure reducer in the DCS, and the heat network user data, store them in the real-time database, and perform data preprocessing and mean filtering to obtain a valid data set;

[0130] The collaborative optimization scheduling module 202 is used to solve the total boiler load adjustment within the device constraints and calculate the boiler load setpoint, boiler main steam pressure setpoint, turbine main steam pressure setpoint, turbine power setpoint, and desuperheater load setpoint.

[0131] The steam turbine delay execution module 203 is used to determine whether the boiler load adjustment is completed and output a steam turbine adjustment instruction;

[0132] The collaborative optimization control module 204 is used to determine whether the boiler-turbine-network collaborative optimization is effective according to the system status, and assign the scheduling optimization set value to the boiler APC and steam turbine DEH target value to perform optimization control.

[0133] This embodiment proposes a device for collaborative optimization and scheduling of boilers and turbines for cogeneration and regional heating. The device collects basic data for processing to obtain a valid data set, and obtains the total boiler load adjustment by real-time tracking changes in heat network user sub-meter flow, steam turbine back pressure, large user pressure, end-user pressure, and the sum of large user flow. The collaborative optimization scheduling parameters of the boiler, steam turbine, and desuperheater are calculated based on this. On this basis, the collaborative optimization scheduling parameters are assigned to the corresponding control parameters of the boiler APC and steam turbine DEH, realizing automatic judgment, adjustment, and control of the system, and rapidly responding to changes in heat network user load, thereby ensuring the smooth operation of the steam supply network pressure, reducing the labor intensity of operators, and saving energy and reducing carbon emissions.

[0134] Example 3

[0135] This embodiment proposes a schematic flow chart of a boiler-machine network coordinated optimization scheduling process for cogeneration district heating. Figure 3shown.

[0136] In the core module of the present application, the collaborative optimization scheduling of boiler and turbine network is carried out by calculating the change in the heat network user sub-meter, the change in the steam turbine back pressure, the large user pressure, the end user pressure and the sum of the large user flow as the contribution to obtain the total boiler load adjustment, thereby obtaining the optimized scheduling parameters of the boiler, steam turbine and desuperheater.

[0137] In the boiler-turbine network collaborative optimization control module, the obtained boiler optimized scheduling parameters are first assigned to the boiler's APC control target value for execution. The turbine delay execution module determines whether the boiler adjustment is complete. Once the adjustment is complete, the turbine and desuperheater optimized scheduling parameters are assigned to the turbine DEH and desuperheater control target values ​​for execution. Before assigning these boiler-turbine network collaborative optimization scheduling parameters to control target values, it is necessary to determine whether the upper and lower limits of the equipment constraints are met.

[0138] Example 4

[0139] The boiler-machine-network collaborative optimization scheduling method and device for cogeneration regional heating proposed in this application are applied to a cogeneration enterprise.

[0140] Figure 4 By comparing the coordinated optimization of boilers, turbines and heating networks with manual operation during the period when the system was not in operation, the coordinated optimized scheduling control of boilers, steam turbines and heating networks under frequent fluctuations and adjustments in the heating network user load was realized. The system adjustment response time was shortened by more than 5 minutes, and the timeliness of the steam supply load scheduling response was improved. Figure 4 The continuous line in the figure is the coal feeding amount of the boiler under manual operation, and the step line is the operation signal sent by the boiler-machine network.

[0141] Figure 5 The steam supply main pipe pressure curve before and after the commissioning of the boiler-machine network was optimized and dispatched in a coordinated manner. The pressure operation stability rate of the steam supply network was improved by 16.63%, the dynamic balance of steam was optimized, and the network pressure was stabilized.

[0142] This invention provides a method and device for collaborative optimization scheduling of boilers, turbines, and networks for cogeneration district heating. When heat users' steam loads frequently adjust, the network load is used as a feedforward signal to adjust the boiler load in advance, and the steam turbine is operated in conjunction with it, achieving collaborative optimization of the boiler, turbine, and network. By assigning collaborative optimization scheduling parameters to the corresponding control parameters of the boiler's APC and turbine's DEH, the system automatically determines, adjusts, and controls, rapidly responding to changes in heat network user loads. This ensures stable operation of the steam supply network pressure, reduces operator workload, and reduces energy consumption and carbon emissions.

[0143] It should be noted that in other embodiments, the steps of the corresponding method are not necessarily performed in the order shown and described in this specification. In some other embodiments, the method may include more or fewer steps than those described in this specification. In addition, a single step described in this specification may be broken down into multiple steps for description in other embodiments, and multiple steps described in this specification may be combined into a single step for description in other embodiments.

[0144] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The system and system embodiments described above are merely illustrative, and some or all of the modules therein can be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying any creative work.

Claims

1. A method for coordinated optimization scheduling of boiler and power grid for cogeneration district heating, characterized in that: The following steps are involved: S1, collects the operating data of boilers, turbines, desuperheaters and heat network users in the distributed control system and stores them in a real-time database. The stored data is then preprocessed and mean filtered to obtain a valid data set. S2: Based on the obtained valid data set, a boiler-turbine network collaborative optimization scheduling model is established. The total boiler load adjustment is obtained within the device constraints. Based on the total boiler load adjustment, the boiler load setpoint, boiler main steam pressure setpoint, turbine main steam pressure setpoint, turbine power setpoint, and desuperheater / pressure reducer load setpoint are calculated. S3, optimizing the boiler APC load and the boiler APC main steam pressure target value based on the obtained boiler load set value and boiler main steam pressure set value; S4, establishing a steam turbine delayed execution model, based on the obtained steam turbine main steam pressure set value, steam turbine power set value, and desuperheater load set value, optimizing the steam turbine DEH main steam pressure value, steam turbine power target value, and desuperheater load target value according to whether the boiler load adjustment is completed; The boiler-machine-network collaborative optimization scheduling model at least includes a steam turbine exhaust pressure sub-model, a boiler load adjustment total sub-model, a boiler double reduction adjustment sub-model, a steam turbine adjustment sub-model and a boiler adjustment sub-model; The boiler-machine network collaborative optimization scheduling model is divided into a fast process and a slow process to calculate the total amount of boiler load adjustment. In the slow process, the total amount of boiler load adjustment includes the contribution of the change of heat network user sub-meter flow rate to the total amount of boiler load adjustment, the contribution of the change of steam turbine back pressure to the total amount of boiler load adjustment, the contribution of large user pressure to the total amount of boiler load adjustment, and the contribution of end-user pressure to the total amount of boiler load adjustment; In the fast process, the total amount of boiler load adjustment includes the contribution of the sum of large user flows to the total amount of boiler load adjustment. The speed of system adjustment is determined by the adjustment flags 0, 1, and 2. When the adjustment flag is 0, the slow process is performed, and when the adjustment flags are 1 or 2, the fast process is performed. After execution, the adjustment flag is incremented by 1. When the adjustment flag is less than 0 or greater than 2, it is reset to 0. The total boiler load adjustment sub-model is used to calculate the total boiler load adjustment according to the load changes of the heating network users, and is calculated according to formula (1): ΔQ=q fb +q by +q dhpre +q mdpre +q dhflow (1) Where, ΔQ is the total amount of boiler load adjustment, t / h; q fb The contribution of the flow change of the heat network user's meter to the total boiler load adjustment, in t / h; q by The contribution of turbine back pressure change to the total boiler load adjustment, in t / h; q dhpre The contribution of large user pressure to the total boiler load adjustment, in t / h; q mdpre The contribution of the end-user pressure to the total boiler load adjustment, in t / h; q dhflow The contribution of the sum of large user flows to the total boiler load adjustment, in t / h; The turbine adjustment sub-model is used to calculate the turbine main steam pressure setting value according to formula (8) based on the total boiler load adjustment amount calculated by formula (1), and to calculate the turbine power setting value according to formula (9). Power qjset =a+b·(x+ΔQ) (9) Where, Pre qjset is the set value of the main steam pressure of the steam turbine, in MPa; Pre qjgoal is the target value of the main steam pressure of the steam turbine, in MPa; is the change in the main steam pressure of the steam turbine, in MPa; k preqj The adjustment step of the main steam pressure of the steam turbine, in MPa; is the number of times the main steam pressure of the steam turbine is adjusted; ΔQ is the total amount of boiler load adjustment, in t / h; α is the characteristic factor of the main steam pressure adjustment of the steam turbine, Power qjset is the turbine power setting value, in MW; a is the turbine model constant; b is the turbine model coefficient; x is the turbine main steam flow, in t / h; The boiler bed temperature and the rate of change of the boiler main steam pressure are calculated based on the turbine delay execution model, and the completion of the boiler load adjustment is determined according to formula (11): Where DelayDone is the steam turbine delay completion status; ΔCWJZ is the average bed temperature change rate of boiler i, which is the ratio of the bed temperature change to time. The bed temperature is obtained from the real-time database and the unit is ℃ / min. is the threshold value of the average temperature change rate of boiler bed i, in °C / min; is the main steam pressure change rate of boiler i, which is the ratio of the main steam pressure change to time, and the unit is MPa / min; is the threshold value of the main steam pressure change rate of boiler i, in MPa / min; After the boiler load adjustment is completed, the steam turbine main steam pressure setting value obtained by formula (8) and the steam turbine power setting value obtained by formula (9) are assigned to the corresponding target value of the steam turbine DEH according to the current mode state of the steam turbine. The target value includes the steam turbine main steam pressure setting value and the steam turbine power setting value, where: If the turbine is in main steam pressure mode, the turbine main steam pressure setting value is assigned to the turbine DEH main steam pressure value; If the turbine is in power mode, the turbine power setting value is assigned to the turbine DEH power value; If the turbine is in manual mode, no value is assigned; If the steam turbine is at full load, the total amount of boiler load adjustment will be assigned to the desuperheater and pressure reducer load setting value.

2. The method for coordinated optimization scheduling of boiler and network for cogeneration district heating according to claim 1, characterized in that: The boiler operation data includes at least: boiler main gas flow, boiler main steam pressure, bed temperature, boiler APC load target value, boiler APC main steam pressure target value, coal feeder manual state, boiler APC communication state, boiler APC one-key cut-off state and boiler APC pressure regulation mode state; The steam turbine operation data includes at least: steam turbine inlet flow, steam turbine back pressure, steam turbine extraction flow, steam turbine exhaust flow, steam turbine power generation, steam turbine main steam pressure target value, steam turbine power target value, steam turbine pressure regulation mode status, steam turbine power mode status and steam turbine manual mode status; The desuperheater and pressure reducer operation data include at least: the desuperheater and pressure reducer inlet flow, pressure and temperature; the desuperheater and pressure reducer outlet pressure and temperature; the desuperheater and pressure reducer flow, pressure and temperature; the desuperheater and pressure reducer pressure regulating valve opening target value and the temperature regulating valve opening target value; The heating network user data at least includes: user meter flow, large user flow, large user pressure, end user flow and end user pressure.

3. The method for coordinated optimization scheduling of boiler and network for cogeneration district heating according to claim 1, characterized in that: The steam turbine exhaust pressure sub-model is used to determine whether the current steam turbine is operating and to determine the reference value of the main steam pressure setting value and the reference value of the power setting value of each steam turbine; When the turbine speed is greater than 2990r / min and the power generation capacity is greater than 5MW, the turbine is considered to be in operation, and the reference values ​​of the turbine main steam pressure and power setting values ​​are the current turbine main steam pressure and power target values.

4. The method for coordinated optimization scheduling of boiler and network for cogeneration district heating according to claim 1, characterized in that: The contribution of the heat network user sub-meter flow change to the total boiler load adjustment q fb Calculate according to formula (2): q fb =k fb ·(fb ave(t) -fb ave(t-1) ) (2) Where q fb is the contribution of the flow change of the heat network user's sub-meter to the total boiler load adjustment, t / h; k fb The flow adjustment coefficient of the heat network user sub-meter; fb ave(t) is the average flow rate of the heating network users at the current moment, t / h; fb ave(t-1) The average flow rate of each heat network user at the previous moment, in t / h; The contribution of the turbine back pressure change to the total boiler load adjustment is q by Calculate according to formula (3): Where q by The contribution of turbine back pressure change to the total boiler load adjustment, in t / h; k by is the adjustment coefficient of the cumulative value of the turbine back pressure change rate; The turbine back pressure change rate is the ratio of the turbine back pressure change to time, and the unit is MPa / min; It is the cumulative value of the turbine back pressure change rate at the previous moment, in MPa / min; The contribution of the large user pressure to the total boiler load adjustment q dhpre Calculate according to formula (4): q dhpre =k dhpre ·Q dhpre (4) Where q dhpre The contribution of large user pressure to the total boiler load adjustment, in t / h; k dhpre Q is the pressure adjustment coefficient for large users; dhpre To meet the pressure of large users, adjust the boiler load in t / h; The contribution of the end-user pressure to the total boiler load adjustment q mdpre Calculate according to formula (5): q mdpre =k mdpre ·Q mdpre (5) Where q mdpre The contribution of the end-user pressure to the total boiler load adjustment, in t / h; k mdpre is the end-user pressure adjustment coefficient; Q mdpre To adjust the boiler load to meet the end-user pressure, the unit is t / h; The contribution of the sum of the large user flows to the total boiler load adjustment is q dhflow Calculate according to formula (6): q dhflow =k dhflow ·( dhflowave(t) - dhflowave(t-1) ) (6) Where q dhflow The contribution of large user flow to the total boiler load adjustment, in t / h; k dhflow Adjust the coefficient for large user traffic; dhflowave(t) is the sum average of the current large user traffic, in t / h; fb ave(t-1) It is the average sum of large user traffic at the previous moment, in t / h.

5. The method for coordinated optimization scheduling of boiler and power grid for cogeneration district heating according to claim 1, characterized in that: The boiler double reduction adjustment sub-model is used to calculate the total boiler load adjustment amount based on formula (1) and the boiler main steam pressure setting value according to formula (7). For glset =k pregl ·ΔQ+For glgoal (7) Where, Pre glset is the boiler main steam pressure setting value, unit is MPa; k pregl is the boiler main steam pressure variation coefficient; ΔQ is the total amount of boiler load adjustment; Pre glgoal The boiler main steam pressure reference value is the boiler APC main steam pressure target value when the boiler APC is in operation, and the maximum main steam pressure of all boilers when not in operation, in MPa.

6. The method for coordinated optimization scheduling of boiler and power grid for cogeneration district heating according to claim 5, characterized in that: The boiler adjustment sub-model is used to determine the load setting value of each boiler based on the total amount of boiler load adjustment calculated by formula (1), wherein the allocation steps are as follows: S21, determining the number of boilers in operation according to the main steam flow of the boilers; S22, judging the boiler APC operation status according to the manual status of the boiler coal feeder, and determining whether the boiler APC is in pressure regulation mode or load regulation mode according to the boiler APC pressure regulation mode status; S23: If the boiler APC is in operation and in pressure adjustment mode, the boiler main steam pressure setting value is calculated according to formula (7). If the boiler APC is in operation and in load adjustment mode, the boiler load setting value is calculated according to formula (10): Where Q glset(i) is the boiler load setting value, t / h; Q glbase(i) is the boiler i load reference value, in t / h; ΔQ is the total boiler load adjustment amount, in t / h; m1 is the threshold value when increasing the boiler load; m2 is the threshold value when reducing the boiler load; Q total It is the total steam production of all boilers, in t / h. F is the total steam production threshold of boilers. is the weight of boiler i’s steam production in the total steam production of boilers.

7. A method for coordinated optimization scheduling of boilers and networks for cogeneration of district heating according to any one of claims 1 to 6, characterized in that: It also includes a disturbance-free switching safety mechanism for achieving switching between collaborative optimization mode and manual operation mode, specifically including: collaborative optimization commissioning of the boiler-machine network; collaborative optimization removal of the boiler-machine network; and disturbance-free switching between collaborative optimization mode and manual operation mode. When any of the above processes is performed, a pop-up window will be displayed for confirmation and sound and color alarms will be issued.

8. The method for collaborative optimization scheduling of a boiler and a network for cogeneration district heating according to claim 7, wherein the seamless switching between the collaborative optimization mode and the manual operation mode specifically comprises: When the system is put into operation, the boiler APC target value and the steam turbine DEH target value are equal to the boiler-turbine-network collaborative optimization set value. When the system is shut down, the boiler-turbine-network collaborative optimization set value, the boiler APC target value and the steam turbine DEH target value are equal to the current real-time value of the system.

9. A method for collaborative optimization scheduling of a boiler-machine network for cogeneration district heating according to claim 8, wherein the collaborative optimization mode includes a boiler-machine network collaborative optimization commissioning mode and a boiler-machine network collaborative optimization removal mode, specifically comprising: The boiler-turbine network collaborative optimization operation mode is realized based on the communication status of the boiler-turbine network collaborative optimization, one-key disconnection of the boiler-turbine network collaborative optimization, manual status of the boiler coal feeder, boiler APC operation status, boiler APC pressure regulation mode status, steam turbine delayed execution completion status, steam turbine main steam pressure mode and steam turbine adjustable status; Based on the collaborative optimization communication status of the boiler network, the manual status of the boiler coal feeder, the boiler APC communication status, the boiler APC one-key cut-off status, the collaborative optimization one-key cut-off status of the boiler network, the boiler load operation status, the boiler pressure operation status, the steam turbine main steam pressure operation status and the automobile power operation status, the collaborative optimization cut-off mode of the boiler network is realized.

10. A device for collaborative optimization scheduling of a boiler and a network for cogeneration of heat and power district heating, used for running the method for collaborative optimization scheduling of a boiler and a network for cogeneration of heat and power district heating according to any one of claims 1 to 9, characterized in that: The boiler-machine network collaborative optimization scheduling device includes: The data processing module is used to collect the operating data of the boiler, turbine, desuperheater and pressure reducer in the distributed control system and heat network user data and store them in the real-time database. It also performs pre-processing and mean filtering on the stored data to obtain a valid data set. The collaborative optimization scheduling module is used to solve the total boiler load adjustment within the device constraints and calculate the boiler load setpoint, boiler main steam pressure setpoint, turbine main steam pressure setpoint, turbine power setpoint, and desuperheater load setpoint based on the total boiler load adjustment; The steam turbine delay execution module is used to determine whether the boiler load adjustment is completed and output the steam turbine adjustment instruction; The collaborative optimization control module is used to determine whether the boiler-turbine-network collaborative optimization is effective based on the system status, and assign the scheduling optimization set value to the boiler APC target value and the steam turbine DEH target value to perform optimization control.

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