Main steam temperature control method and system for incineration boiler of waste incineration power plant

Abstract

Disclosed in the present invention are a main steam temperature control method and system for an incineration boiler of a waste incineration power plant. The method comprises: forming a cascade PID control dual-loop on the basis of a primary desuperheater, a primary superheater, a main PID controller and an auxiliary PID controller, and tuning the cascade PID control dual-loop; obtaining the current main steam flow rate, the current main steam temperature and the current boiler hearth temperature, and the main steam temperature and the boiler hearth temperature after a set delay time; obtaining the current actual waste treatment amount and the density of waste entering the incineration boiler, and calculating a predicted value of the current waste incineration heat; calculating a temperature feedforward value of the main steam temperature; and superimposing the temperature feedforward value and a temperature adjustment value output by the auxiliary PID controller in the cascade PID control dual-loop, generating a control value on the basis of the superimposed value, and controlling the water spraying amount of the primary desuperheater on the basis of the control value. In the present invention, on the basis of conventional PID cascade dual-loop control, correction value feedforward compensation is added to the control loop, thereby effectively improving the stability of the main steam temperature in waste incineration power generation.

Description

A method and system for controlling the main steam temperature of an incineration boiler in a waste incineration power station Technical Field

[0001] The present invention relates to the technical field of main steam temperature control for power generation in garbage power plants, and in particular to a main steam temperature control method and system for an incineration boiler in a garbage incineration power plant. Background Art

[0002] With the advancement of technology, the requirements for incineration power plant boiler units are becoming increasingly stringent. Main steam temperature is a critical controlled parameter in the control of power plant incineration boiler units, an indispensable component for improving the economic efficiency of the power plant and ensuring safe unit operation. Main steam temperature, also known as main steam temperature, is controlled by maintaining the superheater outlet steam temperature within the permitted range, thereby protecting the superheater and ensuring that the tube wall temperature does not exceed the permitted operating temperature. Excessively high or low main steam temperature can affect the safety and economic efficiency of the power plant. The upper limit of the main steam temperature should generally not exceed 5°C above the rated value, and the lower limit should generally not fall below 10°C. Excessively high steam temperature accelerates the creep rate of the boiler heating surface and steam piping metal materials, shortening its service life. Excessively low steam temperature reduces the unit's cycle thermal efficiency and increases coal consumption. Therefore, effective control of main steam temperature is a key indicator of boiler operating quality and is crucial to unit operation.

[0003] Currently, the main steam temperature control of waste incineration power plants typically utilizes single-loop control methods and cascade PID control. The cascade PID control method is widely used in thermal process control systems due to its clear parameter definitions, robustness, and ease of adjustment. However, this control method also has certain drawbacks. For example, the factors influencing changes in main steam temperature are complex. Currently, water spray desuperheating is the primary method used to control steam temperature. However, adjusting the spray rate based solely on the main steam temperature deviation often fails to meet production requirements and results in poor control effectiveness. Due to the long process characteristics of each superheater, the main steam temperature reacts slowly to changes in its control input and the desuperheating water volume of the water spray desuperheater, resulting in significant delays. Furthermore, the steam temperature regulation object is a multi-capacity link with numerous interference factors, and external disturbances change frequently and with large magnitudes, resulting in long-term main steam temperature instability. In other words, existing main steam temperature control schemes generally suffer from large inertia and time lag in the controlled steam temperature object, leading to large fluctuations in the main steam temperature of the entire system and poor control performance. Summary of the Invention

[0004] To address the deficiencies of the above-mentioned prior art, the present invention provides a method and system for controlling the main steam temperature of an incineration boiler in a waste incineration power plant. Based on the traditional PID cascade dual-loop control, a correction value feedforward compensation is added to the control loop. That is, temperature correction feedforward compensation is performed based on parameters such as the main steam flow rate, furnace temperature change rate, predicted waste incineration heat value, and main steam temperature change rate. This improves the stability of the main steam temperature in waste incineration power generation, avoids large fluctuations in the main steam temperature, and improves control performance.

[0005] In a first aspect, the present invention provides a method for controlling the main steam temperature of an incineration boiler in a waste incineration power plant.

[0006] A method for controlling the main steam temperature of an incineration boiler in a waste incineration power station, comprising:

[0007] Based on the desuperheater of this stage, the superheater of this stage, the main PID controller and the auxiliary PID controller, a cascade PID control double loop is formed and the cascade PID control double loop is adjusted;

[0008] Obtain the current main steam flow rate and the current and delayed main steam temperature and boiler furnace temperature;

[0009] Obtain the current actual waste processing volume and the density of waste entering the furnace, and calculate the current waste incineration heat prediction value;

[0010] Calculate the temperature feedforward value of the main steam temperature;

[0011] The temperature feedforward value is superimposed on the temperature adjustment value output by the sub-PID controller in the cascade PID control double loop, and a control value is generated according to the superimposed value. The water spraying amount of the desuperheater at this stage is controlled according to the control value.

[0012] A further technical solution is the method for tuning the cascade PID control dual loop, comprising:

[0013] Initialize and set the parameters of the main PID controller, and set the parameters of the secondary PID controller to 0;

[0014] Place the entire dual-loop control system in a steady state and record the system inputs and outputs;

[0015] Based on the parameters of the main PID controller, the control error is calculated, and according to the PID controller formula, the output u1 of the main PID controller is calculated;

[0016] Take u1 as the input of the sub-PID controller and calculate the output u2 of the sub-controller;

[0017] Use u2 as the control signal of the system, put the system into a new steady state, and record the input and output;

[0018] The control error is calculated based on the parameters of the main PID controller and the sub-PID controller, and the outputs of the main PID controller and the sub-PID controller are calculated according to the PID controller formula;

[0019] Adjust the parameters of the main PID controller and the sub-PID controller according to the system response characteristics;

[0020] Repeat the above steps until the system performance requirements are met and the tuning of the cascade PID control dual loop is completed.

[0021] A further technical solution is to calculate the temperature feedforward value of the main steam temperature, including:

[0022] Based on the current main steam flow, the current waste incineration heat prediction value and the current and delayed main steam flow after the set time

[0023] Steam temperature and boiler furnace temperature, respectively calculate the compensation correction value corresponding to the current main steam temperature actually obtained;

[0024] Based on the main steam flow compensation correction value, the waste incineration heat compensation correction value, the boiler furnace temperature compensation correction value and the main steam temperature compensation correction value, the temperature feedforward value is obtained through weighted sum calculation.

[0025] A further technical solution is to calculate and determine the current main steam temperature based on the current main steam flow rate and a broken line function corresponding to the main steam flow rate and the main steam temperature;

[0026] The difference between the calculated current main steam temperature and the actually obtained current main steam temperature is used as the main steam flow compensation correction value.

[0027] A further technical solution is to calculate the temperature change rate of the main steam temperature based on the main steam temperature before and after the delay setting time;

[0028] According to the temperature change rate and the actual current main steam temperature, the temperature change is calculated and used as the main steam temperature compensation correction value.

[0029] A further technical solution is to calculate the temperature change rate of the boiler furnace temperature based on the boiler furnace temperature before and after the delay setting time; the boiler furnace temperature is the average temperature value of the middle temperature and the upper temperature of the boiler furnace;

[0030] According to the temperature change rate and the actual current main steam temperature, the temperature change is calculated and used as the boiler furnace temperature compensation correction value.

[0031] A further technical solution is to calculate and determine the current main steam temperature based on the current predicted value of the heat of waste incineration and the broken line function corresponding to the predicted value of the heat of waste incineration and the main steam temperature;

[0032] The difference between the calculated current main steam temperature and the actual current main steam temperature is used as the waste incineration heat compensation correction value.

[0033] In a second aspect, the present invention provides a main steam temperature control system for an incineration boiler in a waste incineration power plant.

[0034] A main steam temperature control system for an incineration boiler in a waste incineration power station, comprising:

[0035] The main control loop tuning module is used to form a PID cascade control dual loop based on the current stage desuperheater, current stage superheater, main PID controller and auxiliary PID controller, and to tune the PID cascade control dual loop;

[0036] The data acquisition module is used to obtain the current main steam flow rate, the current and delayed main steam temperature, and the boiler furnace temperature; obtain the current actual waste processing volume and the density of waste entering the furnace, and calculate the current waste incineration heat prediction value;

[0037] A feedforward value calculation module is used to calculate the temperature feedforward value of the main steam temperature;

[0038] The temperature reduction control module is used to superimpose the temperature feedforward value with the temperature adjustment value output by the sub-PID controller in the cascade PID control double loop, generate a control value based on the superimposed value, and control the water spraying amount of the desuperheater at this stage based on the control value.

[0039] In a third aspect, the present invention further provides an electronic device comprising a memory and a processor, and computer instructions stored in the memory and executed on the processor, wherein when the computer instructions are executed by the processor, the steps of the method described in the first aspect are completed.

[0040] In a fourth aspect, the present invention further provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, complete the steps of the method described in the first aspect.

[0041] One or more of the above technical solutions have the following beneficial effects:

[0042] 1. The main steam temperature is one of the main control parameters of a waste incineration power plant. It is controlled by PID control and a desuperheating water regulating valve. The control system has the characteristics of large inertia and large time lag. Therefore, the present invention provides a main steam temperature control method and system for an incineration boiler in a waste incineration power plant. Based on the traditional cascade PID control loop, correction value feedforward compensation is added. Temperature correction feedforward compensation is performed on parameters such as main steam flow, furnace temperature change rate, waste incineration heat prediction value, and main steam temperature change rate. This improves the stability of the main steam temperature of waste incineration power generation, avoids the problem of large fluctuations in the main steam temperature, and improves control performance.

[0043] 2. The cascade PID dual-loop control method for controlling the main steam temperature of the incineration boiler in a waste incineration power plant proposed in the present invention can be implemented in a configuration manner in all distributed control systems (DCS). This can increase the automatic input rate, reduce the amount of operation by operators, and control the maximum dynamic deviation of the steam temperature within 6°C. This effectively improves the stability of the cascade PID control system and enhances the economic efficiency and safety of the production and operation of waste power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0045] Figure 1 is a block diagram of the traditional cascade PID control double loop;

[0046] Figure 2 is a traditional cascade PID double-loop control logic diagram;

[0047] FIG3 is a block diagram of a main steam temperature control circuit of an incineration boiler according to an embodiment of the present invention;

[0048] FIG4 is a flow chart of a method for controlling the main steam temperature of an incineration boiler in a waste incineration power station according to an embodiment of the present invention;

[0049] FIG5 is a schematic diagram of a main steam temperature control circuit according to an embodiment of the present invention;

[0050] FIG6 is a logic diagram of adding temperature feedforward control in an embodiment of the present invention. DETAILED DESCRIPTION

[0051] It should be noted that the following detailed descriptions are exemplary only and are intended to describe specific embodiments and provide further explanation of the present invention, and are not intended to limit the exemplary embodiments according to the present invention. Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0052] Example 1

[0053] The desuperheater control system for superheated steam is typically a cascade dual-loop control system. The traditional cascade PID control dual-loop structure is shown in Figure 1. Taking a secondary desuperheater and a secondary superheater as examples, the control logic is shown in Figure 2. This cascade PID control loop consists of two loops: an inner and outer loop: a secondary PID controller loop and a primary PID controller loop. The inner loop consists of the desuperheater, the secondary PID controller, the desuperheater water control valve, and the desuperheater in series. The outer loop consists of the superheater, the primary PID controller, and the entire inner loop in series. The main steam temperature at the superheater outlet is the controlled variable of the primary control loop. Its actual temperature feedback value is fed into the primary loop and compared with the main steam temperature setpoint to form the temperature deviation of the superheater outlet steam temperature. The desuperheater outlet temperature is the controlled variable of the secondary control loop. Its measured temperature value is fed into the secondary loop and compared with its setpoint to form the temperature deviation of the desuperheater outlet steam temperature. The setpoint of the secondary loop is the output of the primary loop controller.

[0054] To improve the dynamic regulation quality under variable load conditions, this embodiment introduces a temperature feedforward value into the control system, as shown in Figure 3. This temperature feedforward value is related to the main steam flow rate, main steam temperature, boiler furnace temperature, and waste incineration heat. By adding a correction value feedforward compensation to the traditional cascade PID control loop, temperature correction feedforward compensation is performed, thereby improving the stability of the main steam temperature of the waste incineration power generation system, avoiding large fluctuations in the main steam temperature, and enhancing control performance. The temperature setpoint of the desuperheater controller is the load function curve under normal boiler operation, or the temperature setpoint is manually entered by the operator based on the boiler's operating status.

[0055] Specifically, this embodiment provides a method for controlling the main steam temperature of an incineration boiler in a waste incineration power plant, as shown in FIG4 , which specifically includes the following steps:

[0056] Based on the desuperheater of this stage, the superheater of this stage, the main PID controller and the auxiliary PID controller, a cascade PID control double loop is formed and the cascade PID control double loop is adjusted;

[0057] Obtain the current main steam flow rate, the current main steam temperature and the boiler furnace temperature after the set delay time; obtain the current actual waste processing volume and the density of waste entering the furnace, and calculate the current waste incineration heat prediction value;

[0058] Calculate the temperature feedforward value of the main steam temperature;

[0059] The temperature feedforward value is superimposed on the temperature adjustment value output by the sub-PID controller in the cascade PID control double loop, and a control value is generated according to the superimposed value. The water spraying amount of the desuperheater at this stage is controlled according to the control value.

[0060] Taking the secondary desuperheater and the secondary superheater as an example, the main steam temperature control method for the incineration boiler of the waste incineration power station proposed in this embodiment is introduced in more detail through the following content.

[0061] As shown in Figure 5, in the original cascade PID double-loop control system, a correction value feedforward compensation is added to the PID control of the inner loop, that is, the estimated garbage heating value correction, the main steam flow conversion correction, the furnace temperature conversion correction and the secondary superheater outlet temperature correction are added to control the maximum dynamic temperature of the main steam temperature within 6°C.

[0062] During the entire control process, the cascade PID control dual loop is first tuned to achieve initial stability of the control system, so that the correction value feedforward compensation can be added later to further stabilize the control system. The tuning process includes:

[0063] 1) Initialize and set the parameters of the main PID controller, including the proportional coefficient Kp, integral time Ti and differential time Td; set the parameters of the secondary PID controller to 0.

[0064] 2) Place the entire dual-loop control system in steady state and record the input and output of the system.

[0065] 3) Calculate the control error based on the parameters of the main PID controller, and calculate the output u1 of the main PID controller according to the PID controller formula.

[0066] 4) Take u1 as the input of the sub-PID controller and calculate the output u2 of the sub-controller.

[0067] 5) Use u2 as the control signal of the system, put the system into a new steady state, and record the input and output.

[0068] 6) Calculate the control error based on the parameters of the main PID controller and the sub-PID controller, and calculate the output of the main PID controller and the sub-PID controller according to the PID controller formula.

[0069] 7) According to the response characteristics of the system, adjust the parameters of the main PID controller and the sub-PID controller to minimize the steady-state error of the system, achieve the fastest response speed and the best stability.

[0070] 8) Repeat the above steps until the system performance requirements are met and the cascade PID control dual loop tuning is completed.

[0071] Secondly, the corresponding data is obtained to calculate the temperature feedforward value of the main steam temperature. In this embodiment, the temperature feedforward value of the main steam temperature is calculated by analyzing and determining the main steam flow rate, main steam temperature, boiler furnace temperature and waste incineration heat as the main factors. The calculation process is as follows:

[0072] Based on the current main steam flow, the current waste incineration heat prediction value, and the current and delayed main steam temperature and boiler furnace temperature, respectively calculate the compensation correction value corresponding to the actual current main steam temperature;

[0073] Based on the main steam flow compensation correction value, the waste incineration heat compensation correction value, the boiler furnace temperature compensation correction value and the main steam temperature compensation correction value, the temperature feedforward value is obtained through weighted sum calculation.

[0074] Furthermore, corresponding main steam temperature compensation correction values ​​are calculated for the main steam flow, main steam temperature, boiler furnace temperature, and waste incineration heat.

[0075] 1) For the main steam flow rate, based on the current main steam flow rate, the current main steam temperature is calculated and determined according to the broken line function corresponding to the main steam flow rate and the main steam temperature; wherein the broken line function is a piecewise function and each segment is a straight line, the main steam flow rate and the main steam temperature are proportional and there is a certain corresponding relationship, which can be obtained through experimental statistical analysis. For example, when the main steam flow rate is small, the corresponding ratio of the main steam flow rate to the main steam temperature is k1, and when the main steam flow rate is small, the corresponding ratio of the main steam flow rate to the main steam temperature is k2;

[0076] The difference between the calculated current main steam temperature and the actually obtained current main steam temperature is used as the main steam flow compensation correction value, which is recorded as ΔT1.

[0077] 2) For the main steam temperature, the temperature change rate of the main steam temperature is calculated based on the main steam temperature before and after the delay setting time. In this embodiment, the delay time is set to 30 seconds, and the temperature change rate is calculated based on the main steam temperature before and after 30 seconds;

[0078] According to the temperature change rate and the actual current main steam temperature, the temperature change is calculated and used as the main steam temperature compensation correction value. That is, according to the actual current main steam temperature, the product of the temperature change rate is calculated, and the difference between the product and the original temperature is used as the main steam temperature compensation correction value, which is recorded as ΔT2.

[0079] 3) Calculate the furnace temperature change rate based on the furnace temperature before and after the set delay time. In this embodiment, the delay time is set to 30 seconds, and the furnace temperature is the average temperature of the middle and upper parts of the furnace.

[0080] According to the temperature change rate and the actual current main steam temperature, the temperature change is calculated and used as the boiler furnace temperature compensation correction value. That is, according to the actual current main steam temperature, the product of the temperature change rate is calculated, and the difference between the product and the original temperature is used as the boiler furnace temperature compensation correction value, which is recorded as ΔT3.

[0081] 4) For the waste incineration heat, based on the current waste incineration heat prediction value, the current main steam temperature is calculated according to the broken line function corresponding to the waste incineration heat prediction value and the main steam temperature. Similarly, the waste incineration heat prediction value is proportional to the main steam temperature and there is a certain corresponding relationship, which can be obtained through experimental statistical analysis;

[0082] The difference between the calculated current main steam temperature and the actually obtained current main steam temperature is used as the waste incineration heat compensation correction value, which is recorded as ΔT4.

[0083] In addition, the estimated heat value of waste incineration can be converted and obtained by parameters such as the thickness and density of the waste layer, the grate speed, the pusher speed, etc. In this embodiment, the current waste incineration heat prediction value is calculated based on the actual waste processing volume and the density of the waste entering the furnace. First, the actual garbage processing volume and the density of garbage entering the furnace are obtained as follows: according to the size structure diagram of the garbage hopper bin of the waste incineration power plant, the real-time volume of the garbage bin is calculated by the broken line function f(x) of the garbage bin material level measurement value and the garbage bin volume; when the garbage crane collects data within a set time from before the garbage crane feeds the garbage at the furnace mouth to after the garbage is fed, the maximum and minimum values ​​of the garbage volume change are calculated, and the garbage volume increased by this feeding is calculated; when the garbage crane feeds the garbage, the weight of the garbage grabbed by the garbage crane each time is collected, and the density of the garbage in the garbage bin of this feeding is calculated by ρ=M / V, and then the density values ​​are accumulated multiple times and the average value is taken; at the same time, the garbage compaction coefficient formed by the accumulation of garbage in the garbage bin is taken into account to calculate the density of the garbage entering the furnace; the volume difference between the two feedings of the garbage crane is multiplied by the average density to obtain the weight change between the two feedings, and the garbage crane's weighing data this time is added to the weight change and then divided by the time interval between the two feedings to obtain the real-time garbage processing volume.

[0084] Furthermore, the current waste incineration heat forecast value is calculated, including:

[0085] According to the thermal balance principle of the boiler, first determine the total input heat of the incinerator = the total output heat, that is, Qi

[0086] =Qo; where the total heat input Qi includes: heat brought in by garbage Qm, heat input by incinerator QCI, heat brought in by primary air QPA, and heat brought in by secondary air QSA; the total heat output Qo includes: steam output heat QST, extraction steam output heat QSE, and feed water input heat QFW.

[0087] Calculate the heat of the air medium: Q = C*(To-TA)*F*ρ; where Q is the heat, C is the specific heat of air, F is the volume flow rate, ρ is the air density, To is the air temperature, and TA is the ambient temperature.

[0088] Calculate the heat of the steam-water medium: Q = F*h; where Q is the heat, F is the mass flow rate, and h is the enthalpy value.

[0089] According to the principle of heat balance, the actual value of the lower heating value (LHV) of the garbage can be inferred by inverse calculation from the above three formulas.

[0090] After obtaining the compensation correction values ​​through the above method, as shown in Figure 6, the sum of these compensation correction values ​​is used as the final temperature feedforward value for the main steam temperature, which is then added to the temperature adjustment value output by the secondary PID controller in the cascade PID control dual loop. In this embodiment, the temperature feedforward value ΔT is calculated through a weighted summation: ΔT = αΔT1 + βΔT2 + γΔT3 + δΔT4; where α, β, γ, and δ are weights.

[0091] Furthermore, the above compensation correction values ​​are applied to the desuperheating water controller after being rate-limited and amplitude-limited. Through the variable load disturbance test, the above parameters are optimized to determine the optimal value of the final parameter.

[0092] As another implementation method, in order to ensure the accuracy of measurement and calculation, and thus ensure the stability of the control system, as shown in Figure 6, in this embodiment, when obtaining parameter data related to main steam flow, main steam temperature, boiler furnace temperature, and waste incineration heat, different measurement methods are used to obtain the measurement data of the measuring point, and quality judgment is performed on the two measurement data of the same measuring point, that is, the accuracy of the measurement of the measuring point is judged, and a measurement method with more accurate and precise measurement is selected.

[0093] Taking the measurement of main steam flow as an example, a differential pressure flowmeter can be used to measure the main steam flow rate. A differential pressure flowmeter calculates flow rate by using the pressure difference generated when steam passes through a pipeline. Specifically, it measures the pressure difference generated when steam passes through a specially designed orifice plate or nozzle. The differential pressure flowmeter then converts the pressure difference into flow rate using the principles of fluid mechanics. This method is simple and can be used in most industrial applications. Alternatively, a calorimeter can be used to measure the mass flow rate of superheated steam. A calorimeter is a flowmeter based on the principle of heat conduction. It contains two sensors: one for measuring the temperature of steam entering the pipeline and the other for measuring the temperature of steam leaving the pipeline. By measuring the inlet and outlet temperature difference and the known thermal conductivity of the pipeline, the mass flow rate of superheated steam can be calculated. This method can meet high accuracy and high temperature requirements. Compare the measurement data obtained above with the standard value to select the more accurate and precise measurement value and measurement method.

[0094] Example 2

[0095] This embodiment provides a main steam temperature control system for an incineration boiler in a waste incineration power plant, comprising:

[0096] The main control loop tuning module is used to form a PID cascade control dual loop based on the current stage desuperheater, current stage superheater, main PID controller and auxiliary PID controller, and to tune the PID cascade control dual loop;

[0097] The data acquisition module is used to obtain the current main steam flow rate, the current and delayed main steam temperature, and the boiler furnace temperature; obtain the current actual waste processing volume and the density of waste entering the furnace, and calculate the current waste incineration heat prediction value;

[0098] A feedforward value calculation module is used to calculate the temperature feedforward value of the main steam temperature;

[0099] The temperature reduction control module is used to superimpose the temperature feedforward value with the temperature adjustment value output by the sub-PID controller in the cascade PID control double loop, generate a control value based on the superimposed value, and control the water spraying amount of the desuperheater at this stage based on the control value.

[0100] Example 3

[0101] This embodiment provides an electronic device, including a memory and a processor, and computer instructions stored in the memory and executed on the processor. When the computer instructions are executed by the processor, the steps in the main steam temperature control method of the incineration boiler of the waste incineration power plant described above are completed.

[0102] Example 4

[0103] This embodiment further provides a computer-readable storage medium for storing computer instructions. When the computer instructions are executed by a processor, the steps in the above-mentioned method for controlling the main steam temperature of the incineration boiler of a waste incineration power plant are completed.

[0104] The steps involved in the above embodiments 2 to 4 correspond to those in the method embodiment 1. For detailed implementation, please refer to the relevant description of embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media that includes one or more instruction sets; it should also be understood to include any medium that can store, encode, or carry an instruction set for execution by a processor and cause the processor to perform any method of the present invention.

[0105] Those skilled in the art will appreciate that the modules or steps of the present invention described above can be implemented using a general-purpose computer device. Alternatively, they can be implemented using program code executable by a computing device, which can then be stored in a storage device and executed by the computing device. Alternatively, they can be fabricated into separate integrated circuit modules, or multiple modules or steps can be fabricated into a single integrated circuit module for implementation. The present invention is not limited to any specific combination of hardware and software.

[0106] The above description is only a preferred embodiment of the present invention. Although the specific implementation of the present invention is described in conjunction with the accompanying drawings, it does not limit the scope of protection of the present invention. Those skilled in the art should understand that on the basis of the technical solution of the present invention, various modifications or variations that can be made by those skilled in the art without creative work are still within the scope of protection of the present invention.

Claims

1. A method for controlling the main steam temperature of an incineration boiler in a waste incineration power plant, characterized in that include: Based on the desuperheater of this stage, the superheater of this stage, the main PID controller and the auxiliary PID controller, a cascade PID control double loop is formed, and the cascade PID control double loop is adjusted; Obtain the current main steam flow rate and the current and delayed main steam temperature, boiler furnace temperature; obtain the current actual waste processing volume and the density of waste entering the furnace, and calculate the current waste incineration heat prediction value; Calculate the temperature feedforward value of the main steam temperature; The temperature feedforward value is superimposed on the temperature adjustment value output by the sub-PID controller in the cascade PID control double loop, a control value is generated according to the superimposed value, and the water spraying amount of the desuperheater at this stage is controlled according to the control value.

2. The method for controlling the main steam temperature of an incineration boiler in a waste incineration power station according to claim 1, characterized in that The cascade PID control dual loop tuning method includes: Initialize and set the parameters of the main PID controller, and set the parameters of the auxiliary PID controller to 0; put the entire dual-loop control system into a steady state, and record the input and output of the system; Based on the parameters of the main PID controller, the control error is calculated, and according to the PID controller formula, the output u1 of the main PID controller is calculated; Take u1 as the input of the sub-PID controller and calculate the output u2 of the sub-controller; Use u2 as the control signal of the system, put the system into a new steady state, and record the input and output; The control error is calculated based on the parameters of the main PID controller and the sub-PID controller, and the outputs of the main PID controller and the sub-PID controller are calculated according to the PID controller formula; Adjust the parameters of the main PID controller and the auxiliary PID controller according to the system response characteristics; Repeat the above steps until the system performance requirements are met and the tuning of the cascade PID control dual loop is completed.

3. The main steam temperature control method for an incineration boiler in a waste incineration power station according to claim 1, characterized in that, Calculate the temperature feedforward value of the main steam temperature, including: Based on the current main steam flow, the current predicted value of waste incineration heat, and the current and delayed set time main steam temperature and boiler furnace temperature, respectively calculate the compensation correction value corresponding to the current main steam temperature actually obtained; Based on the main steam flow compensation correction value, the waste incineration heat compensation correction value, the boiler furnace temperature compensation correction value and the main steam temperature compensation correction value, the temperature feedforward value is obtained through weighted sum calculation.

4. The main steam temperature control method of the incineration boiler in the waste incineration power station according to claim 3, characterized in that, Based on the current main steam flow rate, the current main steam temperature is calculated and determined according to the broken line function corresponding to the main steam flow rate and the main steam temperature; The difference between the calculated current main steam temperature and the actually obtained current main steam temperature is used as the main steam flow compensation correction value.

5. The main steam temperature control method for the incineration boiler of a waste incineration power station according to claim 3, characterized in that, Based on the main steam temperature before and after the delay setting time, the temperature change rate of the main steam temperature is calculated; According to the temperature change rate and the actual current main steam temperature, the temperature change is calculated and used as the main steam temperature compensation correction value.

6. The main steam temperature control method for the incineration boiler of a waste incineration power station according to claim 3, characterized in that, Based on the boiler furnace temperature before and after the delay setting time, the temperature change rate of the boiler furnace temperature is calculated; the boiler furnace temperature is the average temperature value of the middle temperature and the upper temperature of the boiler furnace; According to the temperature change rate and the actual current main steam temperature, the temperature change is calculated and used as the boiler furnace temperature compensation correction value.

7. The method for controlling the main steam temperature of the incineration boiler in a waste incineration power station according to claim 3, characterized in that, Based on the current predicted value of the heat of garbage incineration, the current main steam temperature is calculated and determined according to the broken line function corresponding to the predicted value of the heat of garbage incineration and the main steam temperature; Taking the difference between the calculated current main steam temperature and the actually obtained current main steam temperature as the waste incineration heat compensation correction value.

8. A main steam temperature control system for an incineration boiler in a waste incineration power station, characterized in that, Including: A main control loop tuning module, configured to form a PID cascade control dual loop based on the current stage desuperheater, the current stage superheater, the main PID controller, and the secondary PID controller, and tune the PID cascade control dual loop; A data acquisition module, configured to acquire the current main steam flow rate, the main steam temperature at the current and delayed set times, and the boiler furnace temperature; acquire the current actual waste treatment amount and the waste density entering the furnace, and calculate the predicted value of the current waste incineration heat; A feedforward value calculation module, configured to calculate the temperature feedforward value of the main steam temperature; A desuperheating control module, configured to superimpose the temperature feedforward value and the temperature adjustment value output by the secondary PID controller in the cascade PID control dual loop, generate a control value according to the superimposed value, and control the water injection amount of the current stage desuperheater according to the control value.

9. An electronic device, characterized in that, Including a memory, a processor, and computer instructions stored on the memory and running on the processor. When the computer instructions are run by the processor, the steps of a method for controlling the main steam temperature of an incineration boiler in a waste incineration power station as described in any one of claims 1-7 are completed.

10. A computer-readable storage medium, characterized in that, For storing computer instructions, when the computer instructions are executed by the processor, the steps of a method for controlling the main steam temperature of an incineration boiler in a waste incineration power station as described in any one of claims 1-7 are completed.

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