A biomass self-adaptive blending system and method for a pulverized coal boiler

Abstract

This invention relates to the field of low-carbon combustion and biomass co-firing technology in pulverized coal boilers, and discloses an adaptive biomass co-firing system and method for pulverized coal boilers. The system includes a furnace, a quantitative feeding and coded perturbation unit, a multi-channel switching valve group, and a biomass characteristic parameter unit. The switching valves in the multi-channel switching valve group have one inlet and three outlets, respectively connected to the main combustion zone nozzle, the burnout zone nozzle, and the inerting channel. The method identifies the incremental influence matrix of each feeding branch on each detection area by applying a coded perturbation sequence. Under constraints of slagging, high-temperature corrosion, and burnout risk, it solves for the target feed rate and target injection position of each branch and executes the switching. The identification is re-established after changes in operating conditions. This invention solves the problem in existing technologies that cannot distinguish the furnace influence of each branch and cannot adjust the injection position online by identifying the incremental influence of each branch online, thus achieving precise control and adaptive closed-loop control under safety constraints.

Description

Technical Field

[0001] This invention belongs to the field of low-carbon combustion and biomass co-firing technology of pulverized coal boilers, specifically relating to an adaptive biomass co-firing system and method for pulverized coal boilers. Background Technology

[0002] Against the backdrop of low-carbon energy transition and optimization of existing coal-fired power units, utilizing existing large-scale pulverized coal boilers to co-fire agricultural and forestry waste, wood residues, and other renewable biomass can reduce fossil coal consumption without constructing new independent biomass boilers. Pulverized coal boilers have large capacity, high steam parameters, and relatively high power generation efficiency. If the proportion of biomass replacing heat can be safely and stably increased, it will not only help reduce fossil carbon dioxide emissions per unit of electricity supply but also provide a large-scale consumption pathway for low-grade resources such as straw and forestry residues. Therefore, it has significant implications for energy conservation and emission reduction, resource recycling, and the retrofitting of existing power units.

[0003] Existing biomass co-firing technologies for pulverized coal boilers mainly employ the following methods: mixing and grinding the biomass with coal before feeding it into the pulverized coal burner; independently pulverizing the biomass before feeding it into the raw pulverized coal burner; adding a dedicated biomass burner or directly injecting it into the furnace using a dedicated nozzle; and first gasifying or pyrolyzing the biomass before feeding the product into the furnace. Engineered co-firing projects typically determine a primary co-firing feedstock based on local biomass resource conditions, maintaining relative stability in biomass type, preparation method, and primary fuel characteristics over a relatively long operating period. Therefore, the main challenge in actual operation is usually not the frequent identification of different types of biomass, but rather the significant differences in the combustion of the same biomass at different furnace locations due to boiler load, burner operation combinations, primary and secondary air ratios, furnace ash and slagging conditions, and changes in the local aerodynamic field. Even if the biomass itself remains stable, the impact of the same feed branch on local temperature, wall heat flux, and burnout degree will still vary significantly under different operating conditions.

[0004] For boilers with multiple biomass feed branches and injection zones, the temperature, heat flux, and flue gas composition responses generated by each branch in the furnace are superimposed. It is difficult to determine which specific feed branch is causing an increased risk in a particular sidewall or burner area based solely on changes in total oxygen, total CO, furnace outlet NOx, or single-point temperature, thus hindering precise control. Furthermore, existing control strategies often rely on fixed empirical models or pre-defined operating curves. When boiler load, pulverizer combination, burner angle, secondary air distribution, and ash accumulation status change, these empirical relationships easily become inaccurate. Under conditions of frequent boiler operating changes and dynamic evolution of furnace ash accumulation, fixed-coefficient empirical models cannot maintain control accuracy. When signs of localized slagging, high-temperature corrosion, or burnout risk appear, existing controls typically only reduce the overall biomass co-firing amount, failing to prioritize adjustments to the branches contributing most to the risk area. This approach limits sustainable co-firing ratios and wastes renewable energy. Furthermore, existing biomass nozzles and conveying branches are typically fixedly connected. Even if operators determine the need to change the injection layer based on real-time furnace conditions, it often requires shutting down the branch, manually reversing the pipes, or maintaining a conservative layout for extended periods. This makes it impossible to directly translate furnace monitoring results into online adjustments to the injection spatial position, and lacks a closed-loop control mechanism that combines online identification results with injection spatial position execution. Regarding risk constraints, existing technologies mostly rely on empirical thresholds for judgment, lacking physical risk boundaries based on fuel characteristics and furnace conditions. This makes it difficult to scientifically determine where co-firing is more advantageous under current boiler operating conditions, resulting in a failure to coordinate safety margins and economic efficiency. In terms of system identification, existing combustion optimization technologies mostly employ offline modeling based on historical data or empirical models with fixed coefficients. This is ill-suited to adapt to frequent changes in boiler operating conditions and the dynamic evolution of ash accumulation in the furnace. While active excitation identification methods have applications in process control, effective technical solutions remain lacking in the specific scenario of biomass co-firing in pulverized coal boilers. These challenges include designing excitation signals that do not interfere with normal boiler operation and accurately demodulating the incremental impact of each branch from the strong noise and multivariate coupled furnace response. Summary of the Invention

[0005] The purpose of this invention is to provide a biomass adaptive co-firing system and method for pulverized coal boilers, which solves the technical problems in the prior art that cannot distinguish the incremental impact of each biomass feeding branch on different furnace areas online and cannot adjust the injection position online based on real-time identification results.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a biomass adaptive co-firing system for pulverized coal boilers, comprising a furnace, a quantitative feeding and coding perturbation unit, a multi-way switching valve group, a biomass characteristic parameter unit, an in-furnace response acquisition unit, a response matrix identifier, and a risk constraint distributor; the furnace is provided with a main combustion zone nozzle and a burnout zone nozzle. The quantitative feeding and coding perturbation unit has at least two feeding branch interfaces; The multi-way switching valve group is located downstream of the quantitative feeding and coding perturbation unit, and includes switching valves corresponding one-to-one with each of the feeding branch interfaces. Each switching valve has one inlet and three outlets. The inlet of each switching valve is connected to the corresponding feeding branch interface, and the three outlets of each switching valve are respectively connected to the main combustion zone nozzle, the burnout zone nozzle, and the inerting channel. Each switching valve only connects the inlet to one of the three outlets. The in-furnace response acquisition unit is set in each detection area of ​​the furnace; the response matrix identifier is connected to the in-furnace response acquisition unit and the quantitative feeding and coding perturbation unit respectively; the risk constraint allocator is connected to the biomass characteristic parameter unit, the response matrix identifier, the quantitative feeding and coding perturbation unit and the multi-way switching valve group respectively.

[0007] A further improvement of the present invention is that the switching valve is provided with a reversing body, which is disposed between the inlet and the three outlets.

[0008] A further improvement of the present invention is that the reversing body has three mechanically mutually exclusive connected positions, and the valve body of the switching valve is provided with a wear-resistant ceramic liner or a hard alloy sealing surface.

[0009] A further improvement of the present invention is that the response matrix identifier includes a time delay estimation module and a correlation demodulation identification module. The input of the time delay estimation module is connected to the output of the quantitative feeding and coding perturbation unit and the output of the furnace response acquisition unit. The output of the time delay estimation module is connected to the input of the correlation demodulation identification module. The output of the correlation demodulation identification module is connected to the input of the risk constraint allocator.

[0010] A further improvement of the present invention is that the multi-way switching valve group further includes a valve position feedback element, which is disposed at the outlet of each of the switching valves, and the signal output terminal of the valve position feedback element is connected to the feedback input terminal of the risk constraint distributor.

[0011] A further improvement of the present invention is that the furnace response acquisition unit includes a temperature sensor, a heat flow sensor and a gas analyzer respectively disposed in each of the detection areas.

[0012] A further improvement of the present invention is that the main combustion zone nozzle is disposed between the coal pulverized burner layers, and the burnout zone nozzle is disposed between the uppermost coal pulverized burner and the burnout air nozzle.

[0013] A further improvement of the present invention is that it also includes a biomass bin and a carrier gas header; the inlet of the switching valve is a biomass powder gas flow inlet, and the three outlets of the switching valve are respectively connected to the main combustion zone nozzle, the burnout zone nozzle, and the inerting channel through the main combustion zone branch, the burnout zone branch, and the inerting return branch; the outlet of the biomass bin is connected to each of the feeding branch interfaces, and the carrier gas header is located downstream of the quantitative feeding and coding perturbation unit and is respectively connected to each of the feeding branch interfaces.

[0014] Secondly, the present invention also provides a method for adaptive co-firing of biomass in a pulverized coal boiler, employing the aforementioned adaptive co-firing system for pulverized coal boilers, comprising the following steps: S1, the characteristic parameters of biomass fuel are obtained through the biomass characteristic parameter unit, and the initial response parameters of each detection area in the furnace are collected through the furnace response acquisition unit to obtain the baseline furnace condition; S2, apply the coded perturbation sequence to each feeding branch through the quantitative feeding and coded perturbation unit, and record the coded perturbation sequence of each feeding branch; S3, the furnace response acquisition unit collects the response parameters of each detection area under the action of the coded perturbation sequence, and the response matrix identifier identifies the incremental influence coefficient of each feeding branch on each detection area according to the coded perturbation sequence and the response parameters, forming an incremental influence matrix; S4, the risk constraint allocator solves for the target feed rate and target injection position of each feed branch under the constraints of slagging risk, high temperature corrosion risk and burnout risk, based on the characteristic parameters output by the biomass characteristic parameter unit and the incremental influence matrix output by the response matrix identifier. The target injection position is one of the main combustion zone nozzle, the burnout zone nozzle or the inerting channel. S5, the feeding amount of each feeding branch is adjusted to the target feeding amount through the quantitative feeding and coding perturbation unit, and each feeding branch is switched to the target injection position through the multi-way switching valve group; S6: When the boiler operating conditions change according to a preset schedule or after a preset running time has elapsed, return to S3 to re-identify the incremental influence matrix.

[0015] A further improvement of this invention is that, in step S3, the transport delay from each branch to each region is determined based on the coded perturbation sequence of each feeding branch and the response sequence of each detection region; after compensating for the transport delay, the incremental influence coefficient is identified; the transport delay is calculated by... Branch coding sequence and the first The time delay corresponding to the maximum value of the cross-correlation function between the response sequences in the detection region is determined; The method for identifying the incremental impact coefficient is as follows: after compensating for the transport delay, the incremental impact coefficient is identified online using a recursive least squares algorithm with a forgetting factor. The recursive formula is:

[0016]

[0017]

[0018] in, For the first Time of the first Feed branch to the first Incremental influence coefficient of the detection area For the first Encoded perturbation sequence of the feed branch, For the first The response sequence of the detection region, For the first Feed branch to the first Transport delay in the detection area For Kalman gain, To estimate the error covariance, It is a forgetting factor.

[0019] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a biomass adaptive co-firing system for pulverized coal boilers. It applies coded perturbations to each feeding branch through a quantitative feeding and coded perturbation unit. A response matrix identifier identifies the incremental influence matrix of each branch on each region of the furnace online based on response parameters collected by the furnace response acquisition unit. On this basis, a risk constraint distributor solves for the target feed rate and target injection position of each branch under constraints of slagging, high-temperature corrosion, and burnout risks. A multi-channel switching valve group performs reversible switching between the main combustion zone nozzle, the burnout zone nozzle, and the inerting channel, thereby forming an online identification... The system recognizes the complete closed loop of spatial execution. Based on this structure, the system can separate the actual incremental impact of each feeding branch on different furnace areas from the normal mixing response by actively encoding micro-perturbation excitation while keeping the biomass type stable. This transforms the traditional black-box experience control into white-box model identification control, significantly reducing the dependence on fixed experience models and operator experience. At the same time, the three-dimensional switching structure forms an executable closed loop of main combustion zone, burnout zone and inerting reflux, which can change the injection area online without stopping the transport feed pipe, adapting to the optimal injection layer requirements under different boiler operating conditions.

[0020] Furthermore, the switching body is located between the inlet and the three outlets of the switching valve. Through this switching body, a mechanical linkage switching mechanism is established between the inlet and the three outlets. Only a single action is needed to connect the inlet to any outlet, eliminating the need to set up an independent valve for each outlet. This simplifies the number of actuators and the complexity of the control logic of the switching valve group, and improves the reliability and response speed of the multi-way switching valve group.

[0021] Furthermore, the response matrix identifier includes a time delay estimation module and a correlation demodulation identification module. The time delay estimation module determines the candidate time delay range based on the length of each feed branch, the carrier gas velocity, and the combustion delay, and calculates the generalized cross-correlation function to determine the transport time delay. The correlation demodulation identification module performs identification after compensating for the transport time delay. Through the cascade structure of time delay estimation and correlation demodulation identification, the physical transmission time delay of biomass fuel from the feed branch through the furnace combustion to the response in the detection area can be accurately compensated, avoiding the impact of time delay mismatch on the identification accuracy and improving the identification accuracy of the incremental influence coefficient.

[0022] Furthermore, the valve position feedback device is installed at the outlet of each switching valve, and its signal output terminal is connected to the feedback input terminal of the risk constraint distributor. Through the valve position feedback device, the actual connection status of each outlet is fed back to the risk constraint distributor in real time, so that the system can confirm whether the switching action is in place according to the feedback signal, and prohibit the resumption of solid feeding when the valve position feedback is inconsistent. This avoids fuel distribution errors or safety accidents caused by the failure of the reversing body to move properly, and improves the position switching safety and reliability of the multi-way switching valve group.

[0023] This invention also provides an adaptive biomass co-firing method for pulverized coal boilers. By acquiring biomass characteristic parameters and baseline boiler conditions, a coded perturbation sequence is applied to each feeding branch. Based on the coded perturbation sequence and response parameters, the incremental influence coefficient of each branch on each detection area is identified, forming an incremental influence matrix. Under constraints of slagging, high-temperature corrosion, and burnout risk, the target feed rate and target injection position of each branch are solved. Feed rate adjustment and injection position switching are executed, and the identification process is repeated after changes in operating conditions, forming a complete closed loop of identification-decision-execution-rolling correction. In this method, paired reverse perturbations make the total biomass heat input approximately constant, with deviations controlled within ±2%. The perturbation amplitude is only 0.5%~5% of the average flow rate. The identification process has minimal interference with main steam parameters and boiler load, and can be continuously executed during normal unit operation. The method incorporates pre-determined stable biomass fuel ash fusion characteristic temperature and alkali metal content... By combining chlorine content with real-time in-furnace regional responses, physical constraints on slagging risk (ash fusion risk margin not less than 50~150℃), high-temperature corrosion risk (corrosion rate not exceeding the maximum allowable value), and burnout risk (CO concentration not exceeding 50~200μL / L, fly ash combustibles not exceeding 4%~8%) are formed. Compared with simple empirical thresholds, this approach can more scientifically determine where co-firing is more advantageous under the current boiler operating conditions. When local risks approach the boundary, the feed branch with the greatest impact on that area is prioritized for adjustment, rather than reducing the overall biomass co-firing rate, avoiding the loss of renewable energy caused by a one-size-fits-all approach. This can significantly increase the sustainable co-firing ratio of biomass under the same safety margin. After changes in operating conditions, the system automatically returns to re-identify the incremental influence matrix, which can adapt to changes in boiler load, burner combination switching, furnace ash accumulation, and soot blowing, maintaining the timeliness of the control model. Attached Figure Description

[0024] The accompanying drawings described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way. Furthermore, the shapes and proportions of the components in the drawings are merely illustrative to aid in understanding the invention and do not specifically limit the shapes and proportions of the components of the invention.

[0025] Figure 1 This is a schematic diagram of the biomass adaptive co-firing system for pulverized coal boilers of the present invention; Figure 2 This is a schematic diagram of a multi-way switching valve assembly. Figure 3 This is a schematic diagram of a response matrix identifier.

[0026] The components are as follows: 100, Furnace; 101, Biomass Bin; 102, Quantitative Feeding and Encoding Perturbation Unit; 103, Carrier Gas Main Pipe; 104, Multi-way Switching Valve Group; 105, Main Combustion Zone Nozzle; 106, Burnout Zone Nozzle; 107, Biomass Characteristic Parameter Unit; 108, Furnace In-furnace Response Acquisition Unit; 109, Response Matrix Identifier; 110, Risk Constraint Distributor; 201, Biomass Powder Carrier Gas Inlet; 202, Reversing Body; 203, Main Combustion Zone Branch; 204, Burnout Zone Branch; 205, Inerting Return Branch; 206, Valve Position Feedback Component; 301, Branch Encoding Perturbation Input; 302, Furnace Transfer Process; 303, Furnace Zone Response Output; 304, Time Delay Compensation and Correlation Demodulation Module; 305, Incremental Influence Matrix. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0029] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0030] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0031] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0032] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0033] The present invention will now be described in further detail with reference to the accompanying drawings: like Figure 1As shown, the present invention provides a biomass adaptive co-firing system for pulverized coal boilers, including a furnace 100, a biomass bin 101, a quantitative feeding and coding perturbation unit 102, a carrier gas header 103, a multi-way switching valve group 104, a main combustion zone nozzle 105, a burnout zone nozzle 106, a biomass characteristic parameter unit 107, an in-furnace response acquisition unit 108, a response matrix identifier 109, and a risk constraint allocator 110. The furnace 100 is provided with a main combustion zone nozzle 105 and a burnout zone nozzle 106; the main combustion zone nozzle 105 is located between the pulverized coal burner layers, and the burnout zone nozzle 106 is located between the uppermost pulverized coal burner and the burnout air nozzle; the outlet of the biomass bin 101 is connected to at least two feeding branches via an airlock device; the quantitative feeding and coding perturbation unit 102 is located on each of the feeding branches, and each feeding branch is provided with an independently adjustable feeding actuator; the carrier gas header 103 is located downstream of the quantitative feeding and coding perturbation unit 102 and is connected to each of the feeding branches; the multi-way switching valve group 104 is located downstream of the carrier gas header 103 and includes switching valves corresponding to each of the feeding branches, with the inlet of each switching valve connected to the outlet of the feed branch. The feeding branch is connected accordingly, and the three outlets of each switching valve are respectively connected to the main combustion zone nozzle 105, the burnout zone nozzle 106, and the inerting channel; the furnace response acquisition unit 108 is set in each detection area of ​​the furnace 100, and the detection area is divided according to the burner layer height, the furnace near wall area, and the furnace outlet, including temperature sensors, heat flow sensors, and gas analyzers respectively set in each detection area; the response matrix identifier 109 is connected to the furnace response acquisition unit 108 and the quantitative feeding and coding perturbation unit 102 respectively; the risk constraint allocator 110 is connected to the biomass characteristic parameter unit 107, the response matrix identifier 109, the quantitative feeding and coding perturbation unit 102, and the multi-way switching valve group 104 respectively. The biomass characteristic parameter unit 107 stores the ash melting characteristic temperature, potassium, sodium and chloride content, moisture, ash content, particle size and lower heating value of the biomass to be blended. The biomass to be blended is a pre-determined biomass fuel. Its ash deformation temperature, ash softening temperature, ash flow temperature, potassium, sodium and chloride content, lower heating value, moisture, ash content and typical particle size are obtained through design experiments or periodic tests. It is not required to continuously identify the fuel type during operation.

[0034] like Figure 2As shown, each switching valve in the multi-way switching valve group 104 has one inlet and three outlets. The inlet is a biomass powder-carrying gas flow inlet 201. The three outlets are respectively connected to the main combustion zone nozzle 105, the burnout zone nozzle 106, and the inerting channel through the main combustion zone branch 203, the burnout zone branch 204, and the inerting return branch 205. Each switching valve is provided with a reversing body 202, which is located between the inlet and the three outlets and has three mechanically mutually exclusive communication positions, allowing only one of the inlet and the three outlets to be connected. The valve body of the switching valve is provided with a wear-resistant ceramic liner or a hard alloy sealing surface. Each switching valve is provided with a valve position feedback element 206 at its outlet.

[0035] like Figure 3 As shown, the response matrix identifier 109 includes a time delay estimation module and a correlation demodulation identification module. The input of the time delay estimation module is connected to the output of the quantitative feeding and coding perturbation unit 102 and the output of the furnace response acquisition unit 108. The output of the time delay estimation module is connected to the input of the correlation demodulation identification module, and the output of the correlation demodulation identification module is connected to the input of the risk constraint allocator 110. The response matrix identifier 109 uses the branch coding perturbation input 301 as a reference signal and receives the furnace partition response output 30 from the furnace response acquisition unit 108. 3. After processing by the time delay compensation and correlation demodulation module 304, the incremental influence matrix 305 is output to the risk constraint allocator 110. The time delay compensation and correlation demodulation module 304 determines the candidate time delay range based on the branch length, carrier gas velocity and combustion delay, determines the transport time delay from each branch to each region through the generalized cross-correlation function, and after compensating for the transport time delay, uses a recursive least squares algorithm with a forgetting factor to identify the incremental influence coefficient of each branch on each region, forming the incremental influence matrix 305. The furnace transfer process 302 represents the physical transfer process of biomass fuel from the feeding branch through the furnace combustion to the response in the detection area.

[0036] This invention also provides a method for adaptive co-firing of biomass in a pulverized coal boiler, employing the aforementioned adaptive co-firing system for pulverized coal boilers, comprising the following steps: S1, the characteristic parameters of biomass fuel are obtained through the biomass characteristic parameter unit 107, and the initial response parameters of each detection area of ​​the furnace 100 are collected through the furnace response acquisition unit 108 to obtain the baseline furnace condition.

[0037] S2, the quantitative feeding and coding perturbation unit 102 applies a coding perturbation sequence to each feeding branch and records the coding perturbation sequence of each feeding branch. To ensure that the boiler heat input remains basically stable during the identification period, two branches are configured as a perturbation pair: the first branch increases the perturbation sequence in one coding cycle. Simultaneously, the second branch reduces the equivalent flow rate calculated based on the lower heat value; the next encoded state changes in the opposite direction. The normalized cross-correlation absolute value of each branch's perturbation sequence within the set time window is no greater than 0.2, and the amplitude of a single branch's perturbation is 0.5% to 5% of the average flow rate. The identification window covers no less than three complete encoding cycles. The perturbation signal uses a pseudo-random binary sequence (PRBS) or a Gold sequence to satisfy the continuous excitation condition and ensure identification convergence.

[0038] S3, the in-furnace response acquisition unit 108 acquires the response parameters of each detection area under the action of the coded perturbation sequence, and the response matrix identifier 109 identifies the incremental influence coefficient of each feeding branch on each detection area based on the coded perturbation sequence and the response parameters, forming an incremental influence matrix. Specifically, the candidate time delay range is determined based on the branch length, carrier gas velocity, and combustion delay. to By calculating the first Branch coding sequence With the Regional response sequence Generalized cross-correlation function between them: (Formula 1) The delay corresponding to the maximum value of the cross-correlation function is taken as the transmission delay from that branch to that region, i.e. (Formula 2) In compensating for the transmission delay Then, a recursive least squares algorithm with a forgetting factor is used to identify the incremental influence coefficient online. The recursive formula is: (Formula 3) (Formula 4) (Formula 5) in, For the first Time of the first Feed branch to the first Incremental influence coefficient of the detection area For the first Encoded perturbation sequence of the feed branch, For the first The response sequence of the detection region, For the first Feed branch to the first Transport delay in the detection area For Kalman gain, To estimate the error covariance, This is the forgetting factor, with a value ranging from 0.95 to 0.995. During initialization... Choose a larger value between 100 and 1000 to ensure sufficient initial gain. Use 0 or historical experience values. During the identification process, for low-frequency changes jointly caused by load commands, total coal volume, and total air volume, extract the first principal component as the common mode using principal component analysis (PCA), or eliminate it using auxiliary variable regression to avoid misjudging common disturbances as branch incremental effects. The resulting incremental influence matrix H is... The row corresponds to the first Feed branch, No. Column corresponding to the first Furnace area, matrix elements This represents the incremental response of regional temperature, heat flux, CO, O2, or flame radiation parameters when the flow rate of this branch changes by a unit; the matrix can be used to establish temperature influence matrices H according to the response type. T Heat flux influence matrix H q Influence matrix H of flue gas components gas .

[0039] S4, the risk constraint allocator 110, based on the characteristic parameters output by the biomass characteristic parameter unit 107 and the incremental influence matrix output by the response matrix identifier 109, solves for the target feed rate and target injection position of each feeding branch under the constraints of slagging risk, high-temperature corrosion risk, burnout risk, and conveying safety risk. The target injection position is one of the main combustion zone, burnout zone, or inerting reflux. The slagging risk constraint is determined by the pre-determined biomass ash softening reference temperature, the high quantile value of the zone temperature, and the dynamic growth rate of the wall heat flux density. Ash fusion risk margin: (Formula 6) in The ash softening temperature is determined in advance according to GB / T 219 or ASTM D1857 for the stable biomass and the designed coal at the specified blending ratio. For the first The high quantile of regional temperature is taken as the 90% to 95% quantile of the regional temperature distribution; For the first The rate of change of heat flux density over time at the zone wall; This is the weighting coefficient for the heat flux growth rate, with units of ℃ / (kW / m²). 2 / s); This indicates that the dynamic margin is deducted only when the heat flux increases, and not additionally deducted when the heat flux decreases or stabilizes; requirements , Use a temperature of 50~150℃.

[0040] The high-temperature corrosion risk constraint is determined by the input flux calculated from the predetermined potassium, sodium, and chloride contents, the wall temperature of the heated surface, and the local oxygen partial pressure. The high-temperature corrosion rate is estimated using an Arrhenius-type empirical kinetic model. (Formula 7) in and The numbers are respectively calculated from the incremental influence matrix H and the alkali metal and chlorine content of biomass. Regional deposition fluxes of alkali metals and chlorine; For the first Thermodynamic temperature of the wall temperature of the heated surface area; This is the universal gas constant; This is the activation energy for the corrosion reaction; For the first Local oxygen partial pressure in the region; These are empirical constants; As a function of oxygen partial pressure, the corrosion rate increases significantly under a reducing atmosphere; requirements: The burnout risk constraint is determined by CO concentration, fly ash combustibles, and furnace outlet temperature. The burnout degree is predicted using a simplified single-step reaction kinetic model. (Formula 8) in, As a pre-exponential factor, its dimensions are the same as... and Matching makes the entire exponential term dimensionless; This refers to the residence time of the flue gas in the high-temperature zone; Oxygen concentration; The reaction order is [number]. This is the activation energy for the burnout reaction; The gas constant is 8.314 J / (mol·K); The flue gas thermodynamic temperature (K) is used. This model is a simplified prediction of burnout; in actual control, the CO concentration at the furnace outlet is used. and fly ash combustibles As a hard constraint, among which Take 50~200μL / L, Take 4%~8%.

[0041] The safety risk constraints for the conveying process are determined by the minimum gas velocity, pressure difference, temperature, oxygen content, and minimum valve holding time in the branch, ensuring that biomass powder does not deposit, spontaneously combust, or backfire in the conveying pipeline.

[0042] The risk-constrained allocator 110 uses the maximization of biomass substitution heat as its objective function. (Formula 9) in For the first Branch biomass feed rate The lower heating value of biomass, The total heat input to the boiler; the average feed flow rate of each branch is calculated under the above four types of constraints. and target injection position The optimization problem is a constrained mixed-integer nonlinear programming problem, which is solved using a sequential quadratic programming (SQP) or model predictive control (MPC) framework. The controller does not adjust parameters based on changes in fuel type, but rather selects the branch that contributes the most to the over-limit area to reduce the amount of fuel or change the injection height based on the matrix H identified under the current boiler operating conditions.

[0043] S5, the feed rate of each feed branch is adjusted to the target feed rate by the quantitative feeding and coding perturbation unit 102, and each feed branch is switched to the target injection position by the multi-way switching valve group 104. When performing injection position switching, the feed rate of the target branch is first reduced to 0~20% of the rated value to maintain the carrier gas; then the reversing body 202 is driven to turn into the inerting reflux position and purged for 5~60 seconds; after the pressure difference between the inlet and the target outlet meets the condition, it is switched to the target position; after receiving double confirmation from the valve position feedback device 206, the feeding is gradually restored. If the valve position feedback is inconsistent, the pressure difference suddenly increases, or the purging is not completed, the restoration of solid feeding is prohibited.

[0044] S6: When the boiler operating conditions change according to a preset schedule or after a preset operating time, return to S3 to re-identify the incremental influence matrix, achieve rolling correction, and maintain the timeliness of the control model. When the unit load change exceeds ±15% of the rated load, the coal mill combination is switched, the burner tilt angle adjustment exceeds ±5 degrees, within 30 minutes after furnace soot blowing, or continuous operation exceeds 24 hours, the original incremental influence matrix is ​​not directly used for a long time. Instead, after the new operating conditions have stabilized for more than 5 minutes, a small-amplitude coded perturbation is reapplied to complete the rolling correction.

[0045] The present invention will be further described in detail below with reference to specific embodiments: In the following embodiments, the pulverized coal boiler co-fires the same type of biomass fuel within a continuous operating cycle. The source, pretreatment process, and main fuel characteristics of the biomass remain relatively stable. Its ash deformation temperature, ash softening temperature, ash flow temperature, alkali metal and chlorine content, moisture, ash content, lower heating value, and typical particle size are determined through testing during the system commissioning phase and recorded in the biomass characteristic parameter unit 107. During operation, the identification of biomass type is not the control objective; instead, changes in boiler load, combustion organization, and furnace zone conditions are the adaptive control targets. The following parameters are used to illustrate the embodiments of the present invention and do not constitute a limitation on the scope of protection.

[0046] Example 1: Corner-cut pulverized coal boiler This embodiment is applied to a 600MW tangentially shaped pulverized coal boiler. Five layers of pulverized coal burners are installed at each of the four corners of the furnace 100, forming a rotating, rising flame in the main burner area. Two layers of separate burnout air (SOFA) are located above the uppermost main burner. The biomass is corn stalks that have been crushed, de-ironized, and dried. Its net calorific value is approximately 14.5 MJ / kg, ash softening temperature is approximately 950℃, chlorine content is approximately 0.3%, and potassium content is approximately 1.2%. After being processed to a particle size of less than 3 mm by an independent preparation system, the biomass enters the biomass silo 101 and is then transported by four independent feeding branches, each with a rated feed rate of 2 t / h. The four feeding branches correspond to the four corners of the furnace 100 and are connected to the main combustion zone nozzle 105, the burnout zone nozzle 106, or the inerting return branch 205 via the switching body 202 in their respective multi-way switching valve groups 104.

[0047] The main combustion zone nozzles 105 are respectively located between the third and fourth layer pulverized coal burners at the four corners. The center lines of the nozzles are arranged according to the original boiler design tangential direction, so that the biomass-carrying airflow entering the furnace 100 is consistent with the rotating airflow formed by the original pulverized coal combustion. The primary air velocity at the nozzles is approximately 25 m / s. The burnout zone nozzles 106 are respectively located between the uppermost main burner and the first layer SOFA nozzles. The main combustion zone nozzles 105 and burnout zone nozzles 106 are fed by the reversing body 202 of the same feed branch, so that the biomass in the same corner can change the injection height without changing the upstream metering reference. Backfire prevention isolation valves and cooling air jackets are installed near the nozzles, and the cooling air is taken from the secondary air header.

[0048] To avoid disrupting the 100° tangential symmetry of the furnace due to changes in biomass distribution, the four branches are arranged diagonally to form perturbation pairs: the first and third corners form the first perturbation pair, and the second and fourth corners form the second perturbation pair. When the first corner branch increases... At that time, the third corner branch reduces the same amount of heat input. Since the biomass at the four corners is identical, it is simplified to equal mass reversed. Another perturbation pair is changed according to different low-correlation codes to keep the total heat input of the biomass at the four corners basically unchanged during the identification period, with a deviation of no more than ±2%. The perturbation signal adopts a 7-level pseudo-random binary sequence (PRBS) with an amplitude of 2% of the average flow rate, a switching period of 30 seconds, an identification window of 15 minutes, and covers about 30 coding cycles.

[0049] The in-furnace response acquisition unit 108 divides the furnace 100 into six detection zones: four near-wall zones (corresponding to the four corner burner zones), the upper zone of the main burner, and the furnace outlet zone. A flame radiation pyrometer (range 800~1800℃) and a wall heat flow meter (range 0~500kW / m²) are installed in the near-wall zones. 2CO, O2, and NOx are collected at the furnace outlet using in-situ laser measurement at a sampling frequency of 1 Hz.

[0050] When the absolute value of the unit load change rate is less than 1% of the rated load per minute, the coal mill combination has not switched in the past 5 minutes, and the furnace negative pressure fluctuation is within ±100Pa, coded perturbations are applied to the four biomass feed branches. The response matrix identifier 109 first determines the candidate time delay range of 0.5~2 seconds based on the branch length (approximately 15m) and carrier gas velocity (approximately 25m / s), and determines the transport time delay from each branch to each area using the generalized cross-correlation method shown in (Equation 1) and (Equation 2); then, a forgetting factor is used. The recursive least squares algorithm (Equations 3-5) with a coefficient of 0.98 identifies the incremental influence matrix H of the four feed branches on the temperature, heat flux, and burnout index of the six furnace zones in region 100. T (4×6), H q (4×6) and H gas (4×6). During initialization Take 500, Set to 0. During the identification process, principal component analysis is used to eliminate common modes of load and total air volume changes.

[0051] Risk-constrained allocator 110 aims to maximize the heat of biomass substitution as shown in Equation 9, and solves for the feed rate and injection location of each branch under the following constraints: Slagging constraint is adopted using (Formula 6), and the ash fusion risk margin for each region is determined. Not less than 80℃, of which Take 950℃, Take the 95th percentile value of the regional temperature. Take 0.5℃ / (kW / m 2 / s). Corrosion constraint is adopted (Formula 7), and the corrosion rate of each region is... Greater than 0.2 mm / year A warning is triggered when the local oxygen partial pressure is below 2% and the wall temperature is above 550℃, based on thermodynamic temperature. The burnout constraint uses (Formula 8): the CO concentration at the furnace outlet is no greater than 100 μL / L, and the combustible content in fly ash is no greater than 6%. The symmetry constraint requires that the deviation of the sum of the biomass heat inputs at the two relative corners does not exceed ±5%. The safety constraint requires that the gas velocity in each branch is no less than 18 m / s, and the pressure difference does not exceed 8 kPa.

[0052] For example, when the identification results show the influence coefficient of the first corner biomass branch on the temperature and heat flux increment of the adjacent water-cooled wall region. Significantly increased (e.g., temperature increment exceeding 5℃ / (t / h), heat flux increment exceeding 10kW / m) 2When the ash fusion risk margin in this area is less than 80℃ (t / h), the risk constraint distributor 110 first reduces the average feed rate of the first corner branch, and simultaneously adjusts the third corner branch according to the tangential symmetrical constraint. If the risk still cannot be recovered, the first corner branch is switched from the main combustion zone nozzle 105 to the burnout zone nozzle 106. The switching process is performed in the following order: freeze the coded perturbation of the first corner branch, reduce the feed rate to 10% of the rated value, maintain the carrier gas, switch to the inerting reflux branch 205 to purge for 20 seconds, and after confirming that the pressure difference is normal, switch to the burnout zone nozzle 106. After receiving confirmation from the valve position feedback device 206, gradually restore the feed rate to the target value. If the CO at the furnace outlet increases significantly after the switch (exceeding 100 μL / L), the total feed rate of this branch is reduced or the other corner branch, which is more favorable for burnout, is kept in the main combustion zone.

[0053] When the unit load changes by more than ±15% of the rated load, the coal mill combination is switched, the burner tilt angle is adjusted by more than ±5 degrees, the furnace is blown at 100°C within 30 minutes, or the continuous operation exceeds 24 hours, the original incremental influence matrix is ​​not directly used for a long time. Instead, after the new operating conditions have been stable for more than 5 minutes, a small-amplitude coded perturbation is applied again to complete the rolling correction, so as to adapt to the changes in the tangent diameter, flame center position and near-wall heat load caused by the boiler operation mode.

[0054] Example 2: Opposed Cyclone Pulverized Coal Boiler This embodiment applies to a 1000MW pulverized coal boiler with swirl burners arranged in a front and rear wall configuration. Four layers of swirl burners are installed on both the front and rear walls, with each layer arranged relatively opposite to the others. Three layers of burnout air (OFA) are installed above the main combustion zone. The biomass is treated wood residue with a net calorific value of approximately 16.8 MJ / kg, an ash softening temperature of approximately 1100℃, a chlorine content of approximately 0.05%, and a potassium content of approximately 0.3%. Six independent feed branches are installed under the biomass silo 101, designated as front wall left, front wall middle, front wall right, rear wall left, rear wall middle, and rear wall right, with a rated feed rate of 3 t / h per branch.

[0055] The main combustion zone nozzle 105 is located in the adjacent area between the second and third swirl burners on the front and rear walls. The nozzle axis faces the center of the furnace 100 and forms a 15° angle with the normal to the water-cooled wall to avoid direct scouring of the water-cooled wall. The burnout zone nozzle 106 is located between the uppermost main burner and the first OFA. Each feed branch is still selectively connected between the main combustion zone nozzle 105, the burnout zone nozzle 106, and the inerting return branch 205 on the corresponding wall via the reversing body 202 in the multi-way switching valve group 104.

[0056] The key control constraint for counter-current cyclone boilers is to maintain a basic balance of fuel input to the front wall, rear wall, and left and right sides. When encoding perturbations, the front wall branch and its corresponding rear wall branch are combined into a reverse perturbation pair: the corresponding front wall branch is increased... At this time, the equivalent heat input of the corresponding branch on the rear wall is reduced to minimize the impact on the total heat input of the boiler and the overall pressure field of the furnace 100. The two sets of perturbations use Gold sequences with low correlation between them, and the normalized cross-correlation absolute value is no greater than 0.15. The perturbation amplitude is 1.5% of the average flow rate, the switching period is 45 seconds, and the identification window is 20 minutes.

[0057] The furnace response acquisition unit 108 acquires parameters such as temperature, wall heat flow, CO, and O2 in eight detection areas: the front wall near the wall (left, middle, and right areas), the rear wall near the wall (left, middle, and right areas), the upper furnace area, and the furnace outlet. Temperature measurement uses an acoustic temperature measurement system to obtain a two-dimensional temperature field distribution; wall heat flow is calculated using the temperature difference and flow rate of the water-cooled wall tubes.

[0058] Under high load (90% THA) conditions, if the heat flux near the wall in the middle of the front wall continues to increase (exceeding 350 kW / m²), 2 Meanwhile, no synchronous changes were observed in the same height area of ​​the rear wall. The response matrix identifier 109 can determine that the biomass branch in the middle of the front wall has the largest contribution to the increase in this high heat flux area (heat flux increment coefficient). More than 8kW / m 2 / (t / h)). Risk constraint distributor 110 reduces the flow rate of the middle branch of the front wall while keeping the total fuel deviation of the front and rear walls within ±5% and the left and right deviation within ±5%, and correspondingly increases the flow rate of the middle or side branches of the rear wall that have less impact on the area; if the local risk of the front wall is still close to the boundary (ash fusion margin is less than 100℃), the branch is switched from the main combustion zone to the nozzle 106 in the burnout zone on the same side.

[0059] Under low load (50% THA) or partial shutdown of swirl burners, if moving the biomass injection position upwards leads to an increase in CO or fly ash combustibles (CO exceeding 150 μL / L or fly ash combustibles exceeding 8%), the risk constraint distributor 110 will, based on the incremental influence matrix, re-switch the branch with the largest burnout contribution back to the main combustion zone and limit the proportion of biomass heat input in the burnout zone to no more than 30% of the total biomass. Thus, the front and rear wall balance, left and right deviations, and burnout constraints of the counter-rotating swirl boiler are all used as conditions for solving the injection position and feed rate, forming a different furnace type adaptation method compared to the diagonal symmetry constraints used in the four-corner tangential circular boiler.

[0060] In both embodiments described above, the safe switching sequence of the multi-way switching valve group 104 is as follows: freeze the corresponding branch code perturbation, reduce or stop the solid feed of that branch, maintain the carrier gas and switch to the inerting return branch 205 for purging, and after confirming that the pipeline pressure difference and valve position feedback device 206 are normal, switch to the target injection position, and then gradually restore the carrier gas and solid feed. When a boiler main fuel trip (MFT), furnace pressure exceeds +3 kPa, delivery pipe temperature exceeds 250°C, spark signal is detected, branch pressure difference exceeds 12 kPa, valve position feedback is contradictory, or carrier gas is interrupted (gas velocity is below 12 m / s), the relevant feeder is immediately stopped and isolation and inerting are performed, and nitrogen or recirculated flue gas with an oxygen volume fraction of less than 8% is introduced.

[0061] Many embodiments and applications beyond the examples provided will be apparent to those skilled in the art upon reading the foregoing description. Therefore, the scope of this teaching should not be determined by reference to the foregoing description, but rather by reference to the foregoing claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed inventive subject matter.

[0062] The above content provides a further detailed description of the present invention. It should not be construed that the specific embodiments of the present invention are limited to this. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all such deductions or substitutions should be considered to fall within the scope of protection of the present invention as defined by the submitted claims.

Claims

1. A biomass adaptive co-firing system for pulverized coal boilers, characterized in that, It includes a furnace (100), a quantitative feeding and coding perturbation unit (102), a multi-way switching valve group (104), a biomass characteristic parameter unit (107), an in-furnace response acquisition unit (108), a response matrix identifier (109), and a risk constraint distributor (110); the furnace (100) is provided with a main combustion zone nozzle (105) and a burnout zone nozzle (106); The quantitative feeding and coding perturbation unit (102) has at least two feeding branch interfaces; The multi-way switching valve group (104) is located downstream of the quantitative feeding and coding perturbation unit (102), and includes switching valves corresponding to each of the feeding branch interfaces. Each switching valve has one inlet and three outlets. The inlet of each switching valve is connected to the corresponding feeding branch interface, and the three outlets of each switching valve are respectively connected to the main combustion zone nozzle, the burnout zone nozzle and the inerting channel. Each switching valve only connects the inlet to one of the three outlets. The furnace response acquisition unit (108) is set in each detection area of ​​the furnace (100); the response matrix identifier (109) is connected to the furnace response acquisition unit (108) and the quantitative feeding and coding perturbation unit (102) respectively; the risk constraint allocator (110) is connected to the biomass characteristic parameter unit (107), the response matrix identifier (109), the quantitative feeding and coding perturbation unit (102) and the multi-way switching valve group (104) respectively.

2. The biomass adaptive co-firing system for pulverized coal boilers according to claim 1, characterized in that, The switching valve is provided with a reversing body (202), which is located between the inlet and the three outlets.

3. The biomass adaptive co-firing system for pulverized coal boilers according to claim 2, characterized in that, The switching body (202) has three mechanically mutually exclusive connected positions, and the valve body of the switching valve is provided with a wear-resistant ceramic liner or a hard alloy sealing surface.

4. The biomass adaptive co-firing system for pulverized coal boilers according to claim 1, characterized in that, The response matrix identifier (109) includes a time delay estimation module and a correlation demodulation identification module. The input of the time delay estimation module is connected to the output of the quantitative feeding and coding perturbation unit (102) and the output of the furnace response acquisition unit (108). The output of the time delay estimation module is connected to the input of the correlation demodulation identification module. The output of the correlation demodulation identification module is connected to the input of the risk constraint allocator (110).

5. The biomass adaptive co-firing system for pulverized coal boilers according to claim 1, characterized in that, The multi-way switching valve group (104) also includes a valve position feedback element (206), which is disposed at the outlet of each of the switching valves. The signal output terminal of the valve position feedback element (206) is connected to the feedback input terminal of the risk constraint distributor (110).

6. The biomass adaptive co-firing system for pulverized coal boilers according to claim 1, characterized in that, The furnace response acquisition unit (108) includes a temperature sensor, a heat flow sensor, and a gas analyzer respectively disposed in each of the detection areas.

7. The biomass adaptive co-firing system for pulverized coal boilers according to claim 1, characterized in that, The main combustion zone nozzle (105) is located between the coal pulverized burner layers, and the burnout zone nozzle (106) is located between the uppermost coal pulverized burner and the burnout air nozzle.

8. The biomass adaptive co-firing system for pulverized coal boilers according to claim 1, characterized in that, It also includes a biomass bin (101) and a carrier gas header (103); the inlet of the switching valve is the biomass powder gas flow inlet (201), and the three outlets of the switching valve are respectively connected to the main combustion zone nozzle (105), the burnout zone nozzle (106) and the inerting channel through the main combustion zone branch (203), the burnout zone branch (204) and the inerting return branch (205); the outlet of the biomass bin (101) is connected to each of the feeding branch interfaces, and the carrier gas header (103) is located downstream of the quantitative feeding and coding perturbation unit (102) and is respectively connected to each of the feeding branch interfaces.

9. A method for adaptive co-firing of biomass in a pulverized coal boiler, characterized in that, The biomass adaptive co-firing system for pulverized coal boilers according to any one of claims 1 to 8 includes the following steps: S1, the characteristic parameters of biomass fuel are obtained through the biomass characteristic parameter unit (107), and the initial response parameters of each detection area of ​​the furnace (100) are collected through the furnace response acquisition unit (108) to obtain the baseline furnace condition; S2, the quantitative feeding and coding perturbation unit (102) applies a coding perturbation sequence to each feeding branch and records the coding perturbation sequence of each feeding branch; S3, the response parameters of each detection area under the action of the coded perturbation sequence are collected by the furnace response acquisition unit (108), and the incremental influence coefficient of each feeding branch on each detection area is identified by the response matrix identifier (109) according to the coded perturbation sequence and the response parameters, forming an incremental influence matrix; S4, the risk constraint allocator (110) calculates the target feed rate and target injection position of each feed branch under the constraints of slagging risk, high temperature corrosion risk and burnout risk, based on the characteristic parameters output by the biomass characteristic parameter unit (107) and the incremental influence matrix output by the response matrix identifier (109). The target injection position is one of the main combustion zone nozzle (105), the burnout zone nozzle (106) or the inerting channel. S5, the feeding amount of each feeding branch is adjusted to the target feeding amount by the quantitative feeding and coding perturbation unit (102), and each feeding branch is switched to the target injection position by the multi-way switching valve group (104); S6: When the boiler operating conditions change according to a preset schedule or after a preset running time has elapsed, return to S3 to re-identify the incremental influence matrix.

10. A method for adaptive co-firing of biomass in a pulverized coal boiler according to claim 9, characterized in that, In S3, the transport delay from each feed branch to each region is determined based on the coded perturbation sequence of each feed branch and the response sequence of each detection region. After compensating for the transport delay, the incremental influence coefficient is identified. The transport delay is calculated by... Branch coding sequence and the first The time delay corresponding to the maximum value of the cross-correlation function between the response sequences in the detection region is determined; The method for identifying the incremental impact coefficient is as follows: after compensating for the transport delay, a recursive least squares algorithm with a forgetting factor is used to identify the incremental impact coefficient online. The recursive formula is: in, For the first Time of the first Feed branch to the first Incremental influence coefficient of the detection area For the first Encoded perturbation sequence of the feed branch, For the first The response sequence of the detection region, For the first Feed branch to the first Transport delay in the detection area For Kalman gain, To estimate the error covariance, It is a forgetting factor.

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