Method and system for coordinated optimization control of gas generator set and furnace of metallurgical captive power plant

Abstract

The application discloses a metallurgical self-provided power plant gas generator set boiler coordination optimization control method and system, regularly collected boiler side DCS and steam turbine side DEH historical process variable data, constructs and updates machine boiler coupling mathematical model; and based on machine boiler coupling mathematical model designs multivariable dynamic matrix controller, with boiler, steam turbine controlled object constitutes machine boiler coordination control system, coordination control system at least periodically completes the following operation: real-time acquisition unit operation data, together with set value input, calculates the current time steam turbine regulating valve opening degree increment and boiler fuel increment; real-time acquisition regulation stage pressure and unit active power feedback correction to system, obtains next time steam turbine regulating valve opening degree and boiler fuel quantity, realizes the collaborative control of boiler and steam turbine, effectively alleviates the problem of low unit efficiency and large fluctuation caused by coal gas pipe network fluctuation, fuel heat value fluctuation, load change and machine boiler dispersed control.

Description

Technical Field

[0001] This invention relates to the field of generator set control technology, specifically to a method and system for coordinated optimization control of gas generator sets and boilers in metallurgical self-owned power plants. Background Technology

[0002] With the rapid development of the metallurgical industry, the demand for electricity supply is constantly increasing. Traditional grid power supply often cannot meet the high-energy-consuming and high-load demands of metallurgical production. Self-owned power plants can provide reliable power guarantees for metallurgical enterprises. At the same time, self-owned power plants can better utilize waste heat and residual heat during metallurgical production, achieving comprehensive energy utilization and energy conservation and emission reduction, which aligns with the sustainable development concept of modern industry. Currently, metallurgical self-owned power plants typically use byproducts from industrial production processes such as blast furnace gas, coke oven gas, and converter gas as combustion media for gas turbine generator sets. However, because metallurgical self-owned power plants are end-users of gas at industrial production sites, the pressure and flow rate of the gas are often fluctuated due to the influence of upstream users. Furthermore, to meet the production requirements of the industrial site, generator sets frequently operate under variable load conditions, which necessitates frequent adjustments to the boiler and turbine to meet production demands. However, for generator sets, frequent unilateral adjustments to the boiler or turbine side can severely affect the unit's operating efficiency and stability.

[0003] Currently, the two common control methods for generator sets are boiler-following-generator (BF) and generator-following-boiler (TF). BF can quickly adapt to load changes, but the pressure before the generator fluctuates significantly, resulting in poor unit stability. TF can maintain stable pressure parameters before the generator, but it cannot respond quickly to load changes. Therefore, researching and establishing a coordinated optimization control system for generator sets and boilers is of great significance for the safe, economical, and stable production of industrial plants. Meanwhile, the control method primarily adopts traditional multivariable proportional-integral-derivative (PID) control. PID control has advantages such as convenient implementation, low model dependence, and simple principle. However, due to the complex characteristics of the combustion process, such as time-varying, strong coupling, multivariable, and nonlinear properties, traditional multivariable PID control has low control quality, leading to problems such as low unit combustion efficiency, severe wear, and high factory electricity consumption, making it difficult to meet the needs of energy conservation, emission reduction, and environmental protection.

[0004] In the prior art, such as Chinese patent application number CN202111074566.5, a method and system for coordinated control of a turbine and boiler are disclosed. This method includes, after the generator set triggers the high main steam pressure protection action, acquiring the target load command and the status signal of the high main steam pressure protection action switch; inputting the target load command into the turbine main control PID controller; and inputting the status signal of the high main steam pressure protection action switch into the boiler main control PID controller. Based on the target load command after the generator set triggers the high main steam pressure protection action, the turbine main control PID controller opens the turbine inlet steam regulating valve to unload the overpressured main steam for power generation, preventing the boiler safety valve from opening and affecting the safe and stable operation of the generator set. Simultaneously, the high pressure protection action switch is connected to the boiler main control PID controller, thereby blocking any increase in the total coal input to the boiler. This ensures that the total coal input regulated by the coordinated control system does not increase after the high main steam pressure protection action, preventing further deterioration and increase in steam pressure. And Chinese Patent Application No. CN202211665387.3 discloses a boiler-turbine coordinated control optimization device and method based on heating load fluctuations. The device includes: a data acquisition and processing module for collecting steam consumption data from all heat users, at least boiler and turbine operating data, and performing preprocessing; an optimization control solution module for determining the optimal operating state of the unit, analyzing the current boiler and turbine operating states, predicting the next stage of operating mode and state, and issuing pre-operation instructions; a unit control module for receiving the pre-operation instructions from the optimization control solution module; an operation execution module for executing the operation instructions from the unit control module; and a signal processing feedback module for feeding back the execution status of the operation execution module to the unit control module and tracking and feeding back its real-time operating parameters and the execution results of the operation execution module. Chinese Patent Application No. CN202310536434.2 discloses a boiler-turbine coordinated optimization method to improve the flexibility of supercritical thermal power units. This method includes the control of the turbine main control and the boiler main control; the boiler main control consists of two parts, namely a feedback loop and a feedforward loop; the turbine main control includes the turbine controlling the load and the boiler controlling the steam pressure; the boiler main control is automatic, and the turbine main control is manual. When the load command changes, the turbine regulator changes the valve opening, thereby changing the steam intake, so that the generator output power can quickly meet the requirements of the external load; the turbine main control obtains the rapid change of boiler steam volume from the heat storage of the boiler body when the external load command changes, resulting in large steam pressure fluctuations, which enables the unit to quickly adapt to the requirements of the external load.

[0005] The aforementioned existing technologies do not take into account the strong coupling between the boiler and the steam turbine when implementing coordinated control of the boiler and the turbine. At the same time, they do not apply intelligent control strategies with superior control performance. Some loops still require manual intervention. During implementation, this may cause large fluctuations in the main steam pressure and load, affecting the stability of unit operation. Therefore, there is an urgent need for a coordinated optimization control method and system for gas generator sets in metallurgical self-owned power plants to solve the above problems. Summary of the Invention

[0006] Addressing the challenges of gas pipeline pressure in metallurgical self-owned power plants being significantly affected by production schedules, large fluctuations in fuel calorific value, variable loads, and decentralized boiler / turbine control, as well as the numerous time-varying, multi-variable, strongly coupled, nonlinear, and influencing factors affecting the combustion and power generation systems, and requiring high stability and precision in the controlled object, this invention provides a method and system for coordinated optimization control of boiler and turbine in gas-fired power plants. This achieves coordinated control of the boiler and turbine, effectively alleviating the problems of low unit efficiency and large fluctuations caused by gas pipeline pressure being significantly affected by production schedules, large fluctuations in fuel calorific value, variable loads, and decentralized boiler / turbine control.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a coordinated optimization control method for gas-fired generator sets in metallurgical self-owned power plants, which involves periodically collecting historical process variable data from the boiler-side DCS and turbine-side DEH to construct and update a coupled mathematical model of the generator set and boiler; and

[0008] A multivariable dynamic matrix controller is designed based on a boiler-turbine coupling mathematical model. This controller, together with the boiler and turbine, forms a coordinated control system. The coordinated control system periodically performs the following operations:

[0009] Real-time unit operation data is collected and input along with set values ​​to calculate the current turbine valve opening increment and boiler fuel increment.

[0010] The system collects real-time data on the regulating stage pressure and the unit's active power to perform feedback correction, thereby obtaining the turbine valve opening and boiler fuel quantity at the next moment.

[0011] Preferably, a time threshold is set, and when the coordinated control system operates for more than the time threshold, historical process variable data of the boiler-side DCS and turbine-side DEH during this period are collected to update the boiler-turbine coupling mathematical model.

[0012] Preferably, the historical process variable data includes: fuel quantity, main steam pressure and regulating valve opening, regulating stage pressure, and active power historical operating data at corresponding times in the boiler-side DCS and turbine-side DEH.

[0013] Preferably, the mechanical-furnace coupling mathematical model is as follows:

[0014]

[0015] Where N is active power, P T Let μ be the main steam pressure, B be the turbine control valve opening, and K1, K2, T1, T2 be the gain and time constant of the process from turbine control valve change to active power change, respectively; K3, T3, τ1 be the gain, time constant, and pure delay time constant of the combustion system, respectively; K4, K5, T4 be the gain and time constant of the process from turbine control valve opening change to main steam pressure change, respectively; and K6, T5, τ2 be the gain, time constant, and pure delay time constant of the combustion system, respectively.

[0016] Preferably, the operating data includes fuel input, main steam pressure, regulating stage pressure, turbine valve opening, and unit active power, and the setpoints include active power setpoints and main steam pressure setpoints.

[0017] Preferably, the specific calculations for the turbine control valve opening increment and boiler fuel increment at the current moment are as follows:

[0018] a. Apply a unit step signal to the turbine-boiler coupled mathematical model and obtain the sampled values ​​of the active power and main steam pressure responses under the unit step signal at sampling time jT (j=1,2,3,…). a j 12 and Where T is the sampling period; and the model of the coordinated control system at any time k is obtained:

[0019]

[0020] in: The output of the system model at time k; Δu h (kj)=u h (kj)-u h (kj-1) represents the control increment, where u1 and u2 represent the turbine control valve opening and boiler fuel quantity, respectively; The step response coefficients of the prediction model are: h = 1 represents the turbine control loop, h = 2 represents the boiler control loop, g = 1 corresponds to the turbine valve opening response, and g = 2 corresponds to the boiler fuel quantity response.

[0021] b. The predicted output of the boiler-machine coordinated control system for n steps starting from time k is:

[0022]

[0023] Where n < p, n is the maximum prediction length, and p is the truncation length; Δu h The resulting vector is reduced to m dimensions, where m is the control length and m < n, and can be represented in matrix form as follows:

[0024]

[0025] in:

[0026] ΔU h =[Δu h (k),Δu h (k+1),…,Δu h (k+m-1)] T ;

[0027]

[0028] c. Establish the objective function for coordinated control of the boiler and turbine:

[0029]

[0030] Where: λ h (i) represents the control weighting coefficient; This is the reference trajectory generated after softening. For a given value; y h (k) is the output value; Softening coefficient The objective function is expressed in matrix form as follows:

[0031]

[0032] W h =[w h (k+1),w h (k+2),…,w h (k+n)] T ;

[0033]

[0034] ΔU h =[Δu h (k),Δu h (k+1),…,Δu h (k+m-1)] T ;

[0035] By finding the minimum value of the control increment in the objective function, the control increment at the current time is obtained as follows:

[0036]

[0037] Where: Δu1(k) is the increase in the turbine control valve opening at time k, and Δu2(k) is the increase in the boiler fuel quantity at time k;

[0038] c T = [1,0,0,…,0];

[0039] Preferably, the system is subjected to feedback correction to obtain the turbine control valve opening and boiler fuel quantity at the next moment:

[0040] a. Based on the control increment at the current moment, the predicted output for the future moment is obtained as follows:

[0041]

[0042] in: This indicates that the prediction at time t = kT is Δu. h (k) The active power and main steam pressure output of the boiler-machine coordinated control system at p future moments during operation; This indicates the prediction without Δu at time t = kT. h (k) The active power and main steam pressure output at p future moments during the operation; This represents the active power and the unit step response of the main steam pressure system at the sampling time.

[0043] b. Based on the actual output y at time k+1 h (k+1) and predicted output The error is weighted and then used to correct the predicted values ​​for other future times:

[0044]

[0045] in: R is the predicted system output at time k+1 after weighted error correction; R = [r1, r2, ..., r p ] T Let r1 be the error correction vector, where r1 = 1; This represents the error between the actual output and the predicted output at time k+1.

[0046] Corrected The initial predicted value at time k+1, used as the initial value for the next time step. Through the corrected prediction vector Shifting yields:

[0047]

[0048] in, It is a shift matrix;

[0049] c. The initial prediction value of the system at the next moment is calculated from the corrected prediction output matrix:

[0050]

[0051] The turbine valve opening control quantity and boiler fuel input quantity for the next moment are calculated:

[0052]

[0053] This invention also discloses a coordinated optimization control system for gas-fired generator sets in metallurgical self-owned power plants, comprising:

[0054] The data interaction subsystem establishes a two-way communication channel with the DCS system and DEH system using the OPC / Modbus communication protocol. It is used to collect historical process variable data from the DCS on the boiler side and the DEH on the turbine side, and to collect real-time operating data such as regulating stage pressure and unit active power to provide feedback correction to the system; as well as to send the turbine valve opening and boiler fuel quantity for the next moment to the unit execution unit.

[0055] The model creation subsystem regularly builds and updates the mechanical-furnace coupling mathematical model;

[0056] The dynamic matrix control subsystem designs a multivariable dynamic matrix control strategy for the coupled mathematical model of the unit established by the current model creation subsystem. Based on the unit operation data collected in real time by the data interaction subsystem, it calculates and corrects the turbine valve opening control quantity and boiler fuel input quantity at the current and future times.

[0057] Beneficial effects: This invention treats the boiler and turbine as a whole and designs a coordinated boiler-turbine control system for it. The fuel input and turbine valve opening are calculated by a multivariable dynamic matrix controller and sent to the DCS and DEH systems. The boiler controller's calculation takes into account the difference between the main steam pressure setting and the regulating stage pressure, and also receives feedback from the load side. Similarly, the turbine controller also receives feedback from the main steam pressure side, thereby achieving coordinated control of the boiler and turbine.

[0058] In addition, a time threshold is set. When the system operates for longer than this threshold, historical process variable data of the boiler-side DCS and turbine-side DEH are collected during this period. The boiler-turbine coupling mathematical model is re-established, and the relevant parameters of the controller are updated based on the newly obtained mathematical model. This realizes the coordinated control of the boiler and turbine, effectively alleviating the problems of low unit efficiency and large fluctuations caused by gas pipeline fluctuations, fuel calorific value fluctuations, load variations, and decentralized boiler-turbine control. Attached Figure Description

[0059] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0060] In the attached diagram:

[0061] Figure 1 This is a block diagram of the coordinated optimization control of the furnace and machine according to the present invention;

[0062] Figure 2 This is the architecture diagram of the furnace-machine coordinated optimization control system of the present invention. Detailed Implementation

[0063] The embodiments of the present invention will now be described with reference to the accompanying drawings. The terminology used in the embodiments section is for illustrative purposes only and is not intended to limit the scope of the invention. The embodiments of this application will now be described with reference to the accompanying drawings.

[0064] Example: Figure 1 As shown, historical process variable data from the boiler-side DCS and turbine-side DEH are collected to establish a boiler-turbine coupling mathematical model. Based on the mathematical model, a multivariable dynamic matrix controller is designed to form a coordinated boiler-turbine control system with the boiler and turbine controlled objects. Simultaneously, real-time unit operating data is collected and input into the control system along with setpoints to calculate the current turbine valve opening increment and boiler fuel increment. Real-time monitoring of the regulating stage pressure and unit active power is also collected to provide feedback correction to the system, obtaining the next turbine valve opening and boiler fuel quantity, which are then sent to the unit execution unit. Furthermore, after a period of system operation, the mathematical model and controller are updated online, specifically including the following steps:

[0065] Historical process variable data of boiler-side DCS and turbine-side DEH are collected periodically. A time threshold is set. When the operation exceeds the time threshold, historical process variable data of boiler-side DCS and turbine-side DEH during this period are collected. Historical operating data of fuel quantity, main steam pressure and regulating valve opening, regulating stage pressure and active power are collected in the boiler DCS system and turbine DEH system at the corresponding time. The collection time can be set, for example, the collection time is 5 seconds. A machine-boiler coupling mathematical model is constructed and updated with active power and main steam pressure as outputs and turbine regulating valve opening and boiler fuel quantity as inputs.

[0066] The mathematical model for the coupling of the furnace and turbine is as follows:

[0067]

[0068] Where N is active power, P TLet μ be the main steam pressure, B be the turbine control valve opening, and K1, K2, T1, T2 be the gain and time constant of the process from turbine control valve change to active power change, respectively; K3, T3, τ1 be the gain, time constant, and pure delay time constant of the combustion system, respectively; K4, K5, T4 be the gain and time constant of the process from turbine control valve opening change to main steam pressure change, respectively; and K6, T5, τ2 be the gain, time constant, and pure delay time constant of the combustion system, respectively.

[0069] A multivariable dynamic matrix controller is designed based on the boiler-turbine coupling mathematical model. This controller, together with the boiler and turbine, forms a coordinated control system. The coordinated control system periodically performs the following operations:

[0070] Real-time acquisition of unit operating data, including fuel input, main steam pressure, regulating stage pressure, turbine valve opening, and unit active power, is input along with setpoints, including active power setpoints and main steam pressure setpoints. The calculation yields the current-moment increment of turbine valve opening and boiler fuel input. Specifically:

[0071] a. Apply a unit step signal to the turbine-boiler coupled mathematical model and obtain the sampled values ​​of the active power and main steam pressure responses under the unit step signal at sampling time jT (j=1,2,3,…). a j 12 and Where T is the sampling period; and the model of the coordinated control system at any time k is obtained:

[0072]

[0073] in: The output of the system model at time k; Δu h (kj)=u h (kj)-u h (kj-1) represents the control increment, where u1 and u2 represent the turbine control valve opening and boiler fuel quantity, respectively; The step response coefficients of the prediction model are: h = 1 represents the turbine control loop, h = 2 represents the boiler control loop, g = 1 corresponds to the turbine valve opening response, and g = 2 corresponds to the boiler fuel quantity response.

[0074] b. Based on the principle of proportional superposition, let the current time be k. The predicted output of the boiler-machine coordinated control system for n steps starting from time k is:

[0075]

[0076] Where n < p, n is the maximum prediction length, and p is the cutoff length; to increase the stability of the boiler-machine coordinated control system and the feasibility of the control quantity, Δu h The resulting vector is reduced to m dimensions, where m is the control length and m < n, and can be represented in matrix form as follows:

[0077]

[0078] in:

[0079] ΔU h =[Δu h (k),Δu h (k+1),…,Δu h (k+m-1)] T ;

[0080]

[0081] in, For p-step prediction of output based on past inputs;

[0082] c. Establish the objective function for coordinated control of the boiler and turbine:

[0083]

[0084] Where: λ h (i) represents the control weighting coefficient; This is the reference trajectory generated after softening. For a given value; y h (k) is the output value; Softening coefficient The objective function is expressed in matrix form as follows:

[0085]

[0086] Wh = [w h (k+1),w h (k+2),…,w h (k+n)] T ;

[0087]

[0088] ΔU h =[Δu h (k),Δu h (k+1),…,Δu h (k+m-1)] T ;

[0089] By finding the minimum value of the control increment in the objective function, the control increment at the current time is obtained as follows:

[0090]

[0091] Where: Δu1(k) is the increase in the turbine control valve opening at time k, and Δu2(k) is the increase in the boiler fuel quantity at time k;

[0092] c T = [1,0,0,…,0];

[0093] The system collects real-time data on regulating stage pressure and unit active power for feedback correction, obtaining the turbine valve opening and boiler fuel quantity for the next moment, and then sends these data to the unit execution unit; specifically:

[0094] a. Based on the control increment at the current moment, the predicted output for the future moment is obtained as follows:

[0095]

[0096] in: This indicates that the prediction at time t = kT is Δu. h (k) The active power and main steam pressure output of the boiler-machine coordinated control system at p future moments during operation; This indicates the prediction without Δu at time t = kT. h (k) The active power and main steam pressure output at p future moments during the operation; This represents the active power and the unit step response of the main steam pressure system at the sampling time.

[0097] b. Based on the actual output y at time k+1 h (k+1) and predicted output The error is weighted and then used to correct the predicted values ​​for other future times:

[0098]

[0099] in: R is the predicted system output at time k+1 after weighted error correction; R = [r1, r2, ..., r p ] T Let r1 be the error correction vector, where r1 = 1; This represents the error between the actual output and the predicted output at time k+1.

[0100] Corrected As the initial value for the next time step, due to the change in the time base point, the predicted future time points will also move to k+2, k+3, ..., k+p+1. Therefore, the initial predicted value at time k+1 is... Through the corrected prediction vector Shifting yields:

[0101]

[0102] in, It is a shift matrix;

[0103] c. The initial prediction value of the system at the next moment is calculated from the corrected prediction output matrix:

[0104]

[0105] The turbine valve opening control quantity and boiler fuel input quantity for the next moment are calculated:

[0106]

[0107] like Figure 2 As shown, the boiler and turbine are considered as a whole in the design of the boiler-turbine coordinated control system. The fuel input and turbine valve opening are calculated by the controller and sent to the DCS and DEH systems. The boiler controller's calculation takes into account the difference between the main steam pressure setting and the regulating stage pressure, and also receives feedback from the load side. Similarly, the turbine controller also receives feedback from the main steam pressure side, so as to achieve coordinated control of the boiler and turbine.

[0108] Based on the above, the present invention also discloses a coordinated optimization control system for gas generator sets in metallurgical self-owned power plants, which is built based on the above method and includes a data interaction subsystem, a model creation subsystem and a dynamic matrix control subsystem.

[0109] The data interaction subsystem establishes a two-way communication channel with the DCS system and DEH system using the OPC / Modbus communication protocol. It is used to collect historical process variable data from the DCS on the boiler side and the DEH on the turbine side, and to collect real-time operating data such as regulating stage pressure and unit active power to provide feedback correction to the system; as well as to send the turbine valve opening and boiler fuel quantity for the next moment to the unit execution unit.

[0110] The model creation subsystem uses an offline identification method to establish a boiler-turbine coupled mathematical model based on historical process variable data from the unit's boiler-side DCS and turbine-side DEH. It can also automatically update the mathematical model at a set time.

[0111] The dynamic matrix control subsystem designs a multivariable dynamic matrix control strategy for the coupled mathematical model of the unit established by the current model creation subsystem. Based on the unit operation data collected in real time by the data interaction subsystem, it calculates and corrects the turbine valve opening control quantity and boiler fuel input quantity at the current and future times.

[0112] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. For those skilled in the art, after learning the contents described in the present invention, several equivalent changes and substitutions can be made without departing from the principle of the present invention. These equivalent changes and substitutions should also be considered to fall within the protection scope of the present invention.

Claims

1. A method for coordinated optimization control of gas-fired generator sets in metallurgical self-owned power plants, characterized by: Historical process variable data from the boiler-side DCS and turbine-side DEH are collected periodically to construct and update the boiler-turbine coupling mathematical model; and A multivariable dynamic matrix controller is designed based on a boiler-turbine coupling mathematical model. This controller, together with the boiler and turbine, forms a coordinated control system. The coordinated control system periodically performs the following operations: Real-time unit operation data is collected and input along with set values ​​to calculate the current turbine valve opening increment and boiler fuel increment. Real-time acquisition of regulating stage pressure and unit active power is used to perform feedback correction on the system, and the turbine valve opening and boiler fuel quantity are obtained at the next moment. Operating data includes fuel input, main steam pressure, regulating stage pressure, turbine valve opening, and unit active power; setpoints include active power setpoint and main steam pressure setpoint. The specific calculations for the turbine control valve opening increment and boiler fuel increment at the current moment are as follows: a. Apply a unit step signal to the turbine-boiler coupled mathematical model and obtain the sampled values ​​of the active power and main steam pressure responses under the unit step signal at sampling time jT (j=1,2,3,…). and Where T is the sampling period; and the model of the coordinated control system at any time k is obtained: in: The output of the system model at time k; Δu h (kj)=u h (kj)-u h (kj-1) represents the control increment, where u1 and u2 represent the turbine control valve opening and boiler fuel quantity, respectively; The step response coefficients of the prediction model are: h = 1 represents the turbine control loop, h = 2 represents the boiler control loop, g = 1 corresponds to the turbine valve opening response, and g = 2 corresponds to the boiler fuel quantity response. b. The predicted output of the boiler-machine coordinated control system for n steps starting from time k is: Where n < p, n is the maximum prediction length, and p is the truncation length; Δu h The resulting vector is reduced to m dimensions, where m is the control length and m < n, and can be represented in matrix form as follows: in: ΔU h =[Δu h (k),Δu h (k+1),…,Δu h (k+m-1)] T ; c. Establish the objective function for coordinated control of the boiler and turbine: Where: λ h (i) represents the control weighting coefficient; i = 1, 2, ..., n are the reference lines generated after softening. For a given value; y h (k) is the output value; Softening coefficient The objective function is expressed in matrix form as follows: W h =[w h (k+1),w h (k+2),…,w h (k+n)] T ; ΔU h =[Δu h (k),Δu h (k+1),…,Δu h (k+m-1)] T ; By finding the minimum value of the control increment in the objective function, the control increment at the current time is obtained as follows: Where: Δu1(k) is the increase in the turbine control valve opening at time k, and Δu2(k) is the increase in the boiler fuel quantity at time k; c T ＝[1,0,0,…,0]； 2. The method for coordinated optimization control of gas-fired generator sets in metallurgical self-owned power plants according to claim 1, characterized in that: A time threshold is set. When the coordinated control system operates for more than the time threshold, historical process variable data of the boiler-side DCS and turbine-side DEH during this period are collected to update the boiler-turbine coupling mathematical model.

3. The method for coordinated optimization control of gas-fired generator sets in metallurgical self-owned power plants according to claim 2, characterized in that: Historical process variable data include: fuel quantity, main steam pressure and regulating valve opening, regulating stage pressure, and active power historical operating data at corresponding times in the boiler-side DCS and turbine-side DEH.

4. The method for coordinated optimization control of gas-fired generator sets in metallurgical self-owned power plants according to claim 1, characterized in that: The mathematical model for the coupling of the furnace and turbine is as follows: Where N is the active power, P T Let μ be the main steam pressure, B be the turbine control valve opening, and K1, K2, T1, T2 be the gain and time constant of the process from turbine control valve change to active power change, respectively; K3, T3, τ1 be the gain, time constant, and pure delay time constant of the combustion system, respectively; K4, K5, T4 be the gain and time constant of the process from turbine control valve opening change to main steam pressure change, respectively; and K6, T5, τ2 be the gain, time constant, and pure delay time constant of the combustion system, respectively.

5. The method for coordinated optimization control of gas-fired generator sets in metallurgical self-owned power plants according to claim 1, characterized in that: The system is then subjected to feedback correction to obtain the turbine control valve opening and boiler fuel quantity at the next moment: a. Based on the control increment at the current moment, the predicted output for the future moment is obtained as follows: in: This indicates that the prediction at time t = kT is Δu. h (k) The active power and main steam pressure output of the boiler-machine coordinated control system at p future moments during operation; This indicates the prediction without Δu at time t = kT. h (k) The active power and main steam pressure output at p future moments during the operation; This represents the active power and the unit step response of the main steam pressure system at the sampling time. b. Based on the actual output y at time k+1 h (k+1) and predicted output The error is weighted and then used to correct the predicted values ​​for other future times: in: R is the predicted system output at time k+1 after weighted error correction; R = [r1, r2, ..., r p ] T Let r1 be the error correction vector, where r1 = 1; This represents the error between the actual output and the predicted output at time k+1. Corrected The initial predicted value at time k+1, used as the initial value for the next time step. Through the corrected prediction vector Shifting yields: in, It is a shift matrix; c. The initial prediction value of the system at the next moment is calculated from the corrected prediction output matrix: The turbine valve opening control quantity and boiler fuel input quantity for the next moment are calculated:

6. A coordinated optimization control system for gas-fired generator sets in metallurgical self-owned power plants, based on the coordinated optimization control method for gas-fired generator sets in metallurgical self-owned power plants according to any one of claims 1-5, characterized in that, include: The data interaction subsystem establishes a two-way communication channel with the DCS system and DEH system using the OPC / Modbus communication protocol. It is used to collect historical process variable data from the DCS on the boiler side and the DEH on the turbine side, and to collect real-time operating data of the regulating stage pressure and the active power of the unit for feedback correction of the system. as well as The turbine control valve opening measurement and boiler fuel quantity for the next moment are sent to the unit execution unit; The model creation subsystem regularly builds and updates the mechanical-furnace coupling mathematical model; The dynamic matrix control subsystem designs a multivariable dynamic matrix control strategy for the coupled mathematical model of the unit established by the current model creation subsystem. Based on the unit operation data collected in real time by the data interaction subsystem, it calculates and corrects the turbine valve opening control quantity and boiler fuel input quantity at the current and future times.

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