Automatic control method and system for gas power generation boiler burner in iron and steel industry

Abstract

The invention discloses an automatic control method and system for a gas power generation boiler burner in the iron and steel industry. The method comprises the steps that an initial pressure set value is generated according to the mapping relation between a target load and main steam pressure, and the initial pressure set value is superposed with manual bias to serve as set value input of a proportional-integral-derivative controller; actual main steam pressure is collected to serve as process variable input of a proportional-integral-derivative controller, and then a first feed-forward signal is output through proportional-integral adjustment; the deviation between the main steam pressure set value and the actual main steam pressure is calculated to serve as steam pressure deviation, the steam pressure deviation is corrected through a lead-lag function, and then a second feedforward signal is generated through filtering processing; and calculating the deviation between the target load and the actual load, and generating a third feed-forward signal through piecewise linear function mapping. According to the design scheme, disturbance factors directly act on feed-forward compensation by bypassing a traditional control method, adjustment is rapid, and system fluctuation is reduced.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of coal gas power generation in the steel industry, and particularly relates to an automatic control method and system for a coal gas power generation boiler burner in the steel industry. BACKGROUND

[0002] In a steel enterprise, coal gas power generation is an important energy utilization and ultra-low emission link. In the traditional coal gas power generation process, the control of the boiler burner is difficult to meet the control requirements due to the fluctuations of factors such as coal gas pressure, coal gas calorific value, and load. The fluctuations of the above factors will cause the burner to exit automatic control and switch to manual control, resulting in the need for frequent manual intervention by operating personnel.

[0003] In view of the above factors, the boiler burner in actual operation currently still mainly relies on manual operation, and there are problems such as low efficiency, slow response, and complex operation. In addition, the labor intensity of employees is large, and the combustion cannot be adjusted in real time according to the coal gas pipe network pressure and the coal gas quality, resulting in energy waste and unstable coal gas pipe network pressure. SUMMARY

[0004] The purpose of the present application is to provide an automatic control method and system for a coal gas power generation boiler burner in the steel industry, which converts the strong disturbance variables specific to the steel industry into a calculable compensation amount through a feedforward main control + feedback auxiliary control architecture, realizes rapid disturbance suppression, multivariable decoupling control, and full-working-condition adaptive effects.

[0005] Based on the specification, the present application provides an automatic control method for a coal gas power generation boiler burner in the steel industry, comprising:

[0006] Obtaining a target load of a generator set, obtaining a main steam pressure set value based on a mapping relationship between the target load of the generator set and the main steam pressure, and inputting the main steam pressure set value superimposed with an artificial bias as a set value input of a proportional-integral-derivative controller;

[0007] Collecting an actual main steam pressure as a process variable input of the proportional-integral-derivative controller, and outputting an output of the proportional-integral-derivative controller as a first feedforward signal;

[0008] Calculating a deviation between the main steam pressure set value and the actual main steam pressure as a steam pressure deviation, correcting the steam pressure deviation through a lead-lag function, filtering the corrected result, and outputting a second feedforward signal;

[0009] Calculating a deviation between the target load and an actual load, and generating a third feedforward signal through a piecewise linear function mapping;

[0010] The first compensation value is obtained by substituting the steam pressure deviation before correction into a steam compensation function, the gas pressure deviation is calculated according to the gas pressure set value and the actual gas pressure value, the second compensation value is obtained by substituting the gas pressure deviation into a gas compensation function, and the fourth feedforward signal is obtained based on the first compensation value and the second compensation value;

[0011] The first to fourth feedforward signals are superimposed to obtain a control signal, and the control signal is output to the burner regulating valve;

[0012] The opening-closing degree feedback data of the burner regulating valve is obtained, and whether to switch from automatic control to manual control is determined according to the opening-closing degree feedback data.

[0013] As a further technical solution, whether to switch to manual control is determined according to the opening-closing degree feedback signal, comprising:

[0014] If the deviation between the opening-closing degree feedback data and the control signal output by the manual-automatic controller is within the set range, the system is in normal operation;

[0015] If the deviation between the opening-closing degree feedback data and the control signal output by the manual-automatic controller exceeds the set range, an alarm is triggered, and manual control is switched by manual operation.

[0016] As a further technical solution, the formula of the steam compensation function is as follows:

[0017] wherein k2=4;

[0018] is the main steam pressure deviation, the unit is MPa, and the physical meaning is the difference between the ideal steam pressure and the actual pressure, is the steam pressure compensation amount, and the physical meaning is the correction amount of the strong gas pressure compensation.

[0019] As a further technical solution, the formula of the gas compensation function is as follows:

[0020] k4=-1.25,

[0021] is the gas pressure deviation, the unit is kPa, and the physical meaning is the difference between the actual gas pressure and the ideal value (8.5kPa); is the gas compensation amount, and the physical meaning is the fuel correction amount caused by the gas pressure fluctuation.

[0022] As a further technical solution, the formula of the piecewise linear function is as follows:

[0023] ,

[0024] Wherein, Y is a load compensation, its physical meaning is a fuel regulating valve opening compensation value, is a load deviation, its unit is MW, its physical meaning is a difference between a planned power generation and an actual power generation.

[0025] Based on the specification, one aspect of the present application provides a steel industry coal gas power generation boiler burner automatic control system, comprising:

[0026] A set value generation module obtains a main steam pressure set value according to a mapping relationship between a target load of a generator set and the main steam pressure, and the main steam pressure set value after superimposing an artificial bias is used as a set value input of a proportional integral derivative controller;

[0027] A PID control module collects an actual main steam pressure as a process variable input of the proportional integral derivative controller, and an output of the proportional integral adjustment is used as a first feedforward signal;

[0028] A first compensation module calculates a deviation between the main steam pressure set value and the actual main steam pressure as a steam pressure deviation, corrects the steam pressure deviation through a lead-lag function, filters a corrected result, and outputs a second feedforward signal;

[0029] A second compensation module calculates a deviation between a target load and an actual load, and generates a third feedforward signal through a piecewise linear function mapping;

[0030] A third compensation module substitutes a steam pressure deviation before correction into a steam compensation function to obtain a first compensation value, calculates a gas pressure deviation according to a gas pressure set value and an actual gas pressure value, substitutes the gas pressure deviation into a gas compensation function to obtain a second compensation value, and sums the first compensation value and the second compensation value as a fourth feedforward signal;

[0031] A control module superimposes the first to fourth feedforward signals to obtain a control signal, and outputs the control signal to a burner regulating valve;

[0032] A tracking feedback module acquires opening-closing degree feedback data of the burner regulating valve, and determines whether to switch from automatic control to manual control according to the opening-closing degree feedback data.

[0033] As a further technical solution, it further comprises a data acquisition module for acquiring an actual load of a generator set, a main steam pressure output by a boiler superheater, and a blast furnace gas main pipe pressure.

[0034] Based on the specification, one aspect of the present application provides a steel industry coal gas power generation boiler burner automatic control system, comprising:

[0035] A steam generator set for driving the generator set to generate power by receiving steam delivered by the boiler;

[0036] A gas-fired boiler for heating water to produce high pressure steam to drive a steam turbine generator set;

[0037] A main steam pressure sensor for detecting the actual main steam pressure at the steam outlet of the gas-fired boiler;

[0038] A load sensor for detecting the actual load of the steam turbine generator set in operation;

[0039] A gas pressure sensor for detecting the actual gas pressure at the gas inlet of the gas-fired boiler;

[0040] A controller for implementing the steps of the automatic control method of a gas-fired boiler burner for a steel industry as claimed in any one of claims 1-5.

[0041] As a further technical solution, the controller comprises:

[0042] A set value generation module for generating a main steam pressure set value according to a function relationship between the target load and the main steam pressure, and adding an artificial bias correction;

[0043] A main steam pressure setting module: an integral function F1(X) and a first adder, for obtaining a main steam pressure set value according to the target load of the generator, and receiving an artificial bias input;

[0044] A proportional-integral-derivative controller: the process variable input end is connected to the actual main steam pressure sensor, the set value input end is connected to the first adder, and the output end generates a first feedforward signal;

[0045] A main steam deviation compensation module: in series with a second adder, a lead-lag function LEADLAG and a filter function SMOOTH, outputting a second feedforward signal;

[0046] A load deviation compensation module: integrated with a third adder and a function F3(X) connected in series, outputting a third feedforward signal;

[0047] A gas pressure compensation module: integrated with a function F4(X) and a function F2(X) connected in parallel, the output ends of the function F4(X) and the function F2(X) are connected to a fourth adder at the same time, outputting a fourth feedforward signal;

[0048] A summation module: the input ends are respectively connected to the output ends of the proportional-integral-derivative controller, the main steam deviation compensation module, the load deviation compensation module and the gas pressure compensation module, and the output end is connected to an execution control unit;

[0049] The execution control unit: contains a hand-automatic switch IAT and a balancing algorithm module BALANCER, and drives a plurality of burner regulating valves.

[0050] Compared with the prior art, the present application has the beneficial effects that:

[0051] 1. The present application relates to the field of coal gas power generation in the steel industry, and particularly relates to a method for automatically controlling a blast furnace coal gas power generation burner in the steel industry, which bypasses the traditional control method and directly acts on the feedforward compensation with a disturbance factor, so that the adjustment is rapid and the system fluctuation is reduced.

[0052] 2. Through the cooperation of the multi-feedforward compensation mechanism and the PID feedback control, the present application directly responds to the strong disturbance (coal gas pressure fluctuation ± 50%, load mutation) specific to the steel industry, greatly reduces the main steam pressure fluctuation amplitude, and at the same time, the automatically generated pressure set value and the non-disturbance switching design improve the automatic operation rate of the system and effectively eliminate the problem of frequent manual intervention, thereby saving the labor cost.

[0053] 3. Through the real-time reverse compensation of the coal gas pressure deviation, the present application automatically supplements fuel when the pressure is reduced and reduces fuel when the pressure is increased, so as to ensure the stability of the coal gas pipe network pressure and reduce energy waste; through the linkage of the load deviation feedforward and the steam pressure dynamic compensation, the present application ensures the accurate matching of fuel supply and power generation demand and avoids the risk of over-oxygen combustion or insufficient oxygen; through the artificial bias ± 2MPa limiting amplitude to prevent overpressure accidents, the lead-lag function (gain 3.0 / lead 8s / lag 20s) inhibits control overshoot, and the risk of equipment damage is eliminated from the source.

[0054] 4. The present application first realizes the unattended automatic control of the coal gas power generation boiler under full load conditions, greatly improves the response speed compared with the traditional PID, provides core algorithm support for the steel enterprise to build a smart energy management and control system, and has the universal value of industry promotion. BRIEF DESCRIPTION OF DRAWINGS

[0055] Figure 1 A steel industry coal gas power generation boiler burner automatic control method process schematic diagram is provided for the embodiments of the present application.

[0056] Figure 2 A steel industry coal gas power generation boiler burner automatic control system schematic diagram is provided for the embodiments of the present application. DETAILED DESCRIPTION

[0057] The technical solutions of the present application will be described in detail below with reference to the drawings in the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application.

[0058] In the description of the present application, it should be noted that the terms "intermediate", "upper", "lower", "left", "right", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0059] As shown in Figure 1 A steel industry coal gas power generation boiler burner automatic control method, comprising:

[0060] The main steam pressure set value is obtained according to the mapping relationship of the target load of the generator set and the main steam pressure, and after superimposing an artificial bias, it is input as the set value of the proportional integral derivative controller;

[0061] It should be noted that the target load of the generator set refers to the work efficiency that the staff wants the generator set to reach, and its unit is MW, and the main steam pressure refers to the steam pressure, which is the output pressure of the boiler superheater, or the input pressure of the steam turbine;

[0062] In this embodiment, the artificial bias correction value is limited within ±2MPa to prevent overcorrection from causing control accidents;

[0063] In this embodiment, the relationship table of the mapping relationship f1(x) is as follows:

[0064] Mapping relationship f1(x) table

[0065]

[0066] The actual main steam pressure is collected as the process variable input of the proportional integral derivative controller, and then the first feedforward signal is output by the proportional integral derivative controller;

[0067] The deviation of the main steam pressure set value and the actual main steam pressure is calculated as the steam pressure deviation, the steam pressure deviation is corrected by the lead-lag function (LEADLAG), and then the second feedforward signal is generated after filtering processing;

[0068] In this embodiment, in the stable state, OUT=IN1xGAIN (except for the limited time). The output reaches 98% of the expected stable state output value in five time constants.

[0069] In this embodiment, the expression of the lead-lag function (LEADLAG) is as follows:

[0070] OUT=(K1*IN1)+(K2*OLDIN1)+(K3*OLDOUT)

[0071] Wherein:

[0072] OUT = new value output, OLD OUT = previous output, IN1 = current input, OLD IN1 = previous input;

[0073] K1 = GAIN (H + 2LEAD) / H + 2LAG) ;

[0074] K2 = GAIN (H + 2LEAD) / H + 2LAG) ;

[0075] K3 = (2LAG - H) / (2LAG + H) ;

[0076] LEAD is a lead time period, LAG is a lag time period, GAIN is a gain coefficient,

[0077] H = sampling time (loop time).

[0078] In this embodiment, the parameters of the lead-lag function are set as follows: gain 3.0; lead time constant 8 seconds; lag time constant 20 seconds, and the filter function uses the SMOOTH smoothing algorithm.

[0079] The deviation of the target load from the actual load is calculated, and a third feedforward signal is generated by mapping a piecewise linear function;

[0080] In this embodiment, the formula of the piecewise linear function is as follows:

[0081] ,

[0082] where Y is the load compensation amount, and its physical meaning is the fuel regulating valve opening compensation value, is the load deviation, and its unit is MW, and its physical meaning is the difference between the planned power generation and the actual power generation;

[0083] In this embodiment, the piecewise linear function mapping is shown in the following table:

[0084] Piecewise linear function mapping table

[0085]

[0086] The first compensation value is obtained by bringing the steam pressure deviation into the steam compensation function, the gas pressure deviation is calculated according to the gas pressure set value and the actual value of the gas pressure, in this embodiment, the gas pressure set value is 8.5 kPa; the second compensation value is obtained by introducing the gas pressure deviation into the gas compensation function, and the sum of the first compensation value and the second compensation value is taken as the fourth feedforward signal;

[0087] In this embodiment, the formula of the steam compensation function is as follows:

[0088] where k2 = 4;

[0089] Psteam is the main steam pressure deviation, unit is MPa, its physical meaning is the difference between ideal steam pressure and actual pressure, Pgas is the steam pressure compensation, its physical meaning is the correction of the compensation of the strong gas pressure;

[0090] In this embodiment, the formula of the gas compensation function is as follows:

[0091] k4=-1.25,

[0092] Pgas is the gas pressure deviation, unit is kPa, its physical meaning is the difference between actual gas pressure and ideal value (8.5 kPa); Pgas is the gas compensation, its physical meaning is the correction of the fuel caused by the fluctuation of the gas pressure;

[0093] It should be noted here that the steam compensation function and the gas compensation function together constitute the fourth feedforward input, when the steam pressure is low, that is, less than 0, the gas pressure compensation effect is amplified.

[0094] In this embodiment, the mapping relationship between the steam compensation function and the gas compensation function is shown in the following table:

[0095] Mapping table of steam compensation function

[0096]

[0097] Mapping table of gas compensation function

[0098]

[0099] The first to fourth feedforward signals are superimposed and output to the burner regulating valve for execution control through the manual automatic controller and the downlink algorithm balance tracker;

[0100] The opening degree feedback data of the burner regulating valve is obtained in real time through the downlink algorithm balance tracker, and the opening degree feedback data is fed back to the controller. Whether the automatic control is replaced by manual control is determined by the controller according to the opening degree feedback data.

[0101] Wherein, whether to switch to manual control is determined according to the opening degree feedback signal, comprising:

[0102] If the opening degree feedback data and the control signal output by the manual automatic controller deviate within the set range, the system is in normal operation;

[0103] If the opening degree feedback data and the control signal output by the manual automatic controller deviate beyond the set range, an alarm is triggered, and manual control is switched by manual operation.

[0104] This embodiment takes a 125 MW coal gas generator set of a certain steel plant as an example to illustrate the specific deployment and running process of the automatic control method in the control terminal (DCS or PLC control system):

[0105] System initialization and parameter setting:

[0106] Target load setting (L_target): The operating personnel set the target power generation load through the console human-machine interface (HMI), for example, 100 MW.

[0107] Main steam pressure set value generation (P_set): The control system automatically calculates the main steam pressure set value according to the preset function F1(X) (for example: P_set = k1 * L_target + b, wherein k1 and b are constants calibrated according to the boiler characteristics) or directly obtains the main steam pressure set value according to the pre-stored mapping relationship table of the target load and the main steam pressure of the generator set. The operating personnel can input an artificial bias correction value ΔP_bias (which is forced to be limited within ±2 MPa by the system) on the HMI according to the actual working conditions (such as the state of the gas pipe network and the boiler efficiency). The correction value is superimposed on the initial set value in the control logic through a first adder to form the final main steam pressure set value P_set.

[0108] Key parameter loading:

[0109] PID controller parameters: proportional band (P), integral time (I), and derivative time (D) are adjusted according to the dynamic characteristics of the boiler.

[0110] Lead-lag function LEADLAG: gain Gain = 3.0, lead time constant T_lead = 8 seconds, and lag time constant T_lag = 20 seconds.

[0111] Filter function: SMOOTH smoothing algorithm is selected, and the time constant is set according to the signal noise level (for example, 5-10 seconds).

[0112] Gas pressure set value (P_g_set): fixedly set as 8.5 kPa.

[0113] Compensation function loading: the mapping relationship tables (such as Tables 2 and 3 in the specification) of the piecewise linear functions F3(X) (used for load deviation compensation), F4(X) (gas pressure compensation), and F2(X) (modification of steam pressure deviation on gas compensation) are preloaded into the control system database.

[0114] Data acquisition and signal generation:

[0115] Real-time data acquisition: The control system acquires the following key real-time signals periodically (e.g. sampling period 1 second) via fieldbus:

[0116] Actual main steam pressure (P_s_actual) - from main steam pressure sensor.

[0117] Actual power generation load (L_actual) - from load sensor.

[0118] Actual blast furnace gas main pressure (P_g_actual) - from gas pressure sensor.

[0119] Signal calculation and generation:

[0120] PID output (FF1): P_set as set value (SV), P_s_actual as process variable (PV), input into PID controller module for calculation, the output is the first feedforward signal FF1. This signal represents the steady-state regulation requirement based on main steam pressure deviation.

[0121] Second feedforward signal (FF2):

[0122] Calculate main steam pressure deviation ΔP_s = P_set - P_s_actual.

[0123] Input ΔP_s into LEADLAG function for dynamic correction (advance action, suppress overshoot).

[0124] Input LEADLAG output into SMOOTH function for filtering, to eliminate noise interference.

[0125] The output of SMOOTH function is the second feedforward signal FF2. This signal quickly responds to the dynamic changes of main steam pressure.

[0126] Third feedforward signal (FF3):

[0127] Calculate load deviation ΔL = L_target - L_actual.

[0128] Input ΔL into piecewise linear function F3(X) (see specification piecewise linear function mapping table) to map and obtain load compensation value Y.

[0129] Y is the third feedforward signal FF3. This signal directly responds to the changes of load instruction.

[0130] Fourth feedforward signal (FF4):

[0131] The gas pressure deviation ΔP_g = P_g_set (8.5kPa) - P_g_actual is calculated.

[0132] The ΔP_g is input into the gas compensation function F4(X) (see the mapping table of gas compensation function in the specification) to obtain the gas compensation amount C_P_g.

[0133] The main steam pressure deviation ΔP_s is input into the steam compensation function F2(X) (see the mapping table of steam compensation function in the specification) to obtain the steam compensation correction amount C_P_s.

[0134] In the fourth adder, the C_P_g and C_P_s are summed: FF4 = C_P_g + C_P_s. The effect of C_P_s is to amplify or reduce the effect of gas pressure compensation (FF4) according to the state of the main steam pressure (lower ΔP_s < 0, C_P_s < 0). This signal is mainly used to quickly suppress strong disturbances of the gas pressure.

[0135] Feedforward synthesis and valve control:

[0136] Feedforward summation (Sum): In the control logic, the four feedforward signals FF1, FF2, FF3, FF4 generated by calculation are superimposed in the summation module: Total_FF = FF1 + FF2 + FF3 + FF4. This total signal represents the comprehensive compensation amount of all major disturbances and regulation requirements.

[0137] Manual-automatic switching (IAT): The Total_FF signal is sent to the manual-automatic switching module (IAT). In the "automatic" mode, Total_FF is passed to the downstream. In the "manual" mode, the operator can directly set the valve opening command on the HMI. The switching process is guaranteed to be disturbance-free (no impact) by the balancer algorithm module (BALANCER).

[0138] Multi-valve balancing control (BALANCER): The output command of the IAT module is sent to the balancer algorithm module (BALANCER). This module is responsible for reasonably distributing the total fuel demand command (Total_FF or manual command) to the multiple burner regulating valves (e.g. 4 or 8) on the boiler. The BALANCER algorithm takes into account factors such as the current opening of each valve, flow characteristics, minimum opening limit, etc., calculates and outputs the independent opening command of each regulating valve (V1_CMD, V2_CMD,...).

[0139] Command issuing and execution: The opening command of each regulating valve is issued to the corresponding valve positioner through I / O module or field bus. The valve positioner drives the regulating valve actuator to change the valve opening, so as to accurately control the blast furnace gas flow into the corresponding burner.

[0140] As shown in Figure 2 the same technical concept as the above embodiment, the present application provides a steel industry coal-fired power plant boiler burner automatic control system, comprising:

[0141] A data acquisition module is configured to acquire actual load of a power generator unit, main steam pressure output by a boiler superheater, and blast furnace gas main pipe pressure.

[0142] A set value generation module is configured to generate an initial pressure set value according to a mapping relationship between a target load and the main steam pressure, and superimpose an artificial bias as a set value input of a proportional-integral-derivative controller.

[0143] A PID control module is configured to acquire an actual main steam pressure as a process variable input of the proportional-integral-derivative controller, and then output a first feedforward signal by proportional-integral adjustment.

[0144] A first compensation module is configured to calculate a deviation between the main steam pressure set value and the actual main steam pressure as a steam pressure deviation, correct the steam pressure deviation by a lead-lag function, and then generate a second feedforward signal by filtering processing.

[0145] A second compensation module is configured to calculate a deviation between a target load and an actual load, and generate a third feedforward signal by a piecewise linear function mapping.

[0146] A third compensation module is configured to derive a first compensation value by introducing the steam pressure deviation into a steam compensation function, calculate a gas pressure deviation according to a gas pressure set value and an actual gas pressure value, derive a second compensation value by introducing the gas pressure deviation into a gas compensation function, and sum the first compensation value and the second compensation value as a fourth feedforward signal.

[0147] A control module is configured to superimpose the first to fourth feedforward signals to obtain a control signal, and output the control signal to a burner regulating valve.

[0148] A tracking feedback module is configured to acquire opening and closing degree feedback data of the burner regulating valve, and determine whether to switch from automatic control to manual control according to the opening and closing degree feedback data.

[0149] Based on the same technical concept as the above embodiment, the present application provides a steel industry coal-fired power plant boiler burner automatic control system, comprising:

[0150] A main steam pressure sensor is configured to detect an actual main steam pressure.

[0151] a load sensor for detecting an actual load;

[0152] a gas pressure sensor for detecting an actual gas pressure;

[0153] a controller for generating an initial pressure set value, and calculating a first to fourth feedforward signal according to the initial pressure set value and the actual main steam pressure, the actual load and the actual gas pressure, and outputting a total control command to the burner control valve through an automatic controller and a down algorithm balance tracker after summing the first to fourth feedforward signals.

[0154] In this embodiment, the controller comprises:

[0155] a set value generating module for generating a main steam pressure set value according to a function relationship between a target load and a main steam pressure, and adding an artificial bias correction;

[0156] a main steam pressure setting module: an integrator F1(X) and a first adder, for generating an initial pressure set value according to a target load, and receiving an artificial bias input;

[0157] a proportional-integral-derivative controller: a process variable input end connected to an actual main steam pressure sensor, a set value input end connected to the first adder, and an output end generating a first feedforward signal;

[0158] a main steam deviation compensation module: a second adder, a lead-lag function LEADLAG and a filter function SMOOTH connected in series, outputting a second feedforward signal;

[0159] a load deviation compensation module: an integrator F3(X) and a third adder connected in series, outputting a third feedforward signal;

[0160] a gas pressure compensation module: an integrator F4(X) and an integrator F2(X) connected in parallel, the output ends of the integrator F4(X) and the integrator F2(X) connected to a fourth adder, outputting a fourth feedforward signal;

[0161] a summing module: input ends connected to the output ends of the proportional-integral-derivative controller, the main steam deviation compensation module, the load deviation compensation module and the gas pressure compensation module, and an output end connected to an execution control unit;

[0162] the execution control unit: containing a manual-automatic switch IAT and a balance algorithm module BALANCER, driving a plurality of burner control valves.

[0163] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely exemplary of the principles and application of the present application. Numerous modifications and adaptions can be effected without departing from the spirit and scope of the present application, which is not limited to the exact construction and arrangement described. It is intended, therefore, to cover all modifications and adaptions that fall within the scope of the claims and their equivalents.

Claims

1. A method for automatic control of a burner of a gas power boiler in the iron and steel industry, characterized in that, The method comprises the following steps: obtaining a target load of a generator set, obtaining a main steam pressure set value according to a mapping relationship between the target load of the generator set and the main steam pressure, and superimposing an artificial bias on the main steam pressure set value to obtain a set value input of a proportional-integral-derivative (PID) controller; acquiring an actual main steam pressure as a process variable input of the PID controller, and outputting a first feedforward signal according to an output of the PID controller; calculating a deviation between the main steam pressure set value and the actual main steam pressure as a steam pressure deviation, correcting the steam pressure deviation through a lead-lag function, filtering a corrected result, and outputting a second feedforward signal; calculating a deviation between the target load and an actual load, and generating a third feedforward signal through a piecewise linear function mapping; obtaining a first compensation value by substituting the steam pressure deviation before correction into a steam compensation function, calculating a gas pressure deviation according to a gas pressure set value and an actual gas pressure value, obtaining a second compensation value by substituting the gas pressure deviation into a gas compensation function, and obtaining a fourth feedforward signal based on the first compensation value and the second compensation value; superimposing the first to fourth feedforward signals to obtain a control signal, and outputting the control signal to a burner regulating valve; and judging whether to switch to manual control according to the opening degree feedback signal, comprising:

2. The automatic control method for a steel industry coal gas power generation boiler burner according to claim 1, characterized in that: if a deviation between the opening degree feedback data and a control signal output by the manual-automatic controller is within a set range, the system is in normal operation; if the deviation between the opening degree feedback data and the control signal output by the manual-automatic controller exceeds the set range, an alarm is triggered, and manual control is switched by manual operation. The formula of the steam compensation function is as follows:

3. The method for automatic control of a gas-fired boiler burner in the steel industry according to claim 1, characterized in that: The formula of the gas compensation function is as follows: where k2= 4; Pdev is the main steam pressure deviation, unit is MPa, its physical meaning is the difference between ideal steam pressure and actual pressure, Pcomp is the steam pressure compensation quantity, its physical meaning is the correction quantity of the enhanced coal gas pressure compensation.

4. The method for automatic control of a gas-fired boiler burner in the steel industry according to claim 1, characterized in that: The formula of the piecewise linear function is as follows: ，k4=-1.25， is the coal gas pressure deviation, in kPa, which physically means the difference between the actual coal gas pressure and the ideal value (8.5 kPa); is the coal gas compensation quantity, which physically means the fuel correction quantity caused by the coal gas pressure fluctuation.

5. The method for automatic control of a gas-fired boiler burner in the steel industry according to claim 1, characterized in that: The method comprises the following steps: ， Wherein, Y is the load compensation quantity, and its physical meaning is the fuel regulating valve opening compensation value, is the load deviation, and its unit is MW, and its physical meaning is the difference between the planned power generation and the actual power generation.

6. An automatic control system for a burner of a coal gas power boiler in the iron and steel industry, characterized in that, a set value generation module obtains a main steam pressure set value according to a mapping relationship between a target load of a generator set and the main steam pressure, and superimposes an artificial bias on the main steam pressure set value to obtain a set value input of a proportional-integral-derivative (PID) controller; a PID control module acquires an actual main steam pressure as a process variable input of the PID controller, and outputs a first feedforward signal according to an output of the PID controller; a first compensation module calculates a deviation between the main steam pressure set value and the actual main steam pressure as a steam pressure deviation, corrects the steam pressure deviation through a lead-lag function, filters a corrected result, and outputs a second feedforward signal; a second compensation module calculates a deviation between the target load and an actual load, and generates a third feedforward signal through a piecewise linear function mapping; a third compensation module obtains a first compensation value by substituting the steam pressure deviation before correction into a steam compensation function, calculates a gas pressure deviation according to a gas pressure set value and an actual gas pressure value, obtains a second compensation value by substituting the gas pressure deviation into a gas compensation function, and outputs a fourth feedforward signal by summing the first compensation value and the second compensation value; a control module superimposes the first to fourth feedforward signals to obtain a control signal, and outputs the control signal to a burner regulating valve. ​ The tracking feedback module acquires the opening degree feedback data of the burner adjusting valve and judges whether to switch from automatic control to manual control according to the opening degree feedback data.

7. The automatic control system for a steel industry cogeneration boiler burner according to claim 6, characterized in that: The data acquisition module is further included for acquiring the actual load of the generator set, the main steam pressure output by the superheater of the boiler and the pressure of the blast furnace gas main pipe.

8. An automatic control system for a gas-fired boiler burner in the steel industry, characterized in that it comprises: a steam generator set for generating power driven by steam delivered by the boiler; a gas-fired boiler for heating water to generate high-pressure steam to provide kinetic energy for the steam generator set; a main steam pressure sensor for detecting the actual main steam pressure at the steam output port of the gas-fired boiler; a load sensor for detecting the actual load of the steam generator set in the working state; a gas pressure sensor for detecting the actual gas pressure at the gas inlet of the gas-fired boiler; a controller for implementing the steps of the automatic control method for the gas-fired boiler burner in the steel industry according to any one of claims 1-5.

9. The automatic control system for a steel industry cogeneration boiler burner according to claim 8, characterized in that: The controller comprises: a main steam pressure setting module: an integrator F1(X) and a first adder, for generating an initial pressure setting value according to the target load and receiving manual bias input; a proportional-integral-derivative controller: the process variable input end is connected to the actual main steam pressure sensor, the setting value input end is connected to the first adder, and the output end generates a first feedforward signal; a main steam deviation compensation module: a second adder, a lead-lag function LEADLAG and a filter function SMOOTH are connected in series, and a second feedforward signal is output; a load deviation compensation module: a third adder and a function F3(X) connected in series are integrated, and a third feedforward signal is output; a gas pressure compensation module: a function F4(X) and a function F2(X) connected in parallel are integrated, the output ends of the function F4(X) and the function F2(X) are connected to a fourth adder at the same time, and a fourth feedforward signal is output; a summation module: the input ends are respectively connected to the output ends of the proportional-integral-derivative controller, the main steam deviation compensation module, the load deviation compensation module and the gas pressure compensation module, and the output end is connected to an execution control unit; the execution control unit: containing a hand-automatic switch IAT and a balancing algorithm module BALANCER, driving a plurality of burner adjusting valves.

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