Automatic control method and system for pressure, oxygen content and temperature of incineration hearth

Abstract

The invention discloses an automatic control method and system for pressure, oxygen content and temperature of an incineration hearth, and the automatic control method comprises the steps: carrying out filtering processing on measured values of the pressure, the oxygen content and the temperature of the incineration hearth, and obtaining stable actual measured values; pID processing is carried out on the stable measurement value and the set value to obtain a PID output value; performing optimization processing on the feed-forward parameter to obtain a feed-forward parameter adjustment instruction; and correcting the PID output value by using the feedforward parameter adjustment instruction to obtain a final adjustment instruction. According to the automatic control method and system, feedforward parameters are introduced to compensate, correct and optimize the measured values of the pressure, the oxygen content and the temperature of the incineration hearth, and accurate adjustment of the pressure, the oxygen content and the temperature of the incineration hearth is achieved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of industrial combustion control, and relates to an automatic control method and system for furnace pressure, oxygen content and temperature of an incinerator. BACKGROUND

[0002] In modern industrial production, incineration heating furnaces, as key thermal equipment, are widely used in many fields such as petroleum, chemical industry, metallurgy, power generation, etc. They undertake the important task of treating waste gas materials, heating steam, crude oil and process gas to meet the needs of subsequent processes. For example, in the petroleum refining process, heating furnaces are used to heat crude oil to an appropriate temperature so that it can undergo key reactions such as fractionation and cracking; in power generation, heating furnaces heat saturated steam to an appropriate temperature for power generation to ensure the quality and performance of the power generation steam. Therefore, the performance of the heating furnace directly affects the stability, efficiency and product quality of the entire production process.

[0003] Furnace pressure, oxygen content and temperature have a crucial impact on the performance and production of incinerators. The stability of the furnace pressure directly affects the safety and thermal efficiency of the incineration heating furnace. If the furnace pressure is too high, it may cause high-temperature flue gas leakage, leading to safety accidents, and increase the heat loss of the exhaust gas, reducing the thermal efficiency; if the furnace pressure is too low, it will cause a large amount of cold air to enter the furnace, also reducing the thermal efficiency and possibly affecting the stability of the combustion. The oxygen content in the furnace directly affects the combustion efficiency of the fuel and the emission of pollutants. An appropriate oxygen content can ensure complete combustion of the fuel, improve thermal efficiency and reduce the generation of pollutants; while too high or too low oxygen content will lead to incomplete combustion, increasing fuel consumption and pollutant emissions. The furnace temperature not only determines the heating speed of the materials and the effect of waste gas treatment, but is also closely related to fuel consumption. If the furnace temperature is too high, it may cause overheating and overburning of the materials, affecting product quality and increasing fuel consumption; if the furnace temperature is too low, it will cause insufficient heating of the materials and incomplete treatment of the waste gas, failing to meet the requirements of the production process and safe emission of flue gas.

[0004] For example, in the incineration furnace of waste gas and liquid in a chemical plant, the existing furnace pressure control is a single-loop pressure control system composed of a pressure transmitter, a pressure controller and a induced draft fan frequency converter, as shown in Figure 4 The flue gas oxygen content control is a single-loop control system composed of a zirconia transmitter, a zirconia controller and a combustion air fan frequency converter, as shown in Figure 5 The furnace temperature control is a single-loop temperature control system composed of a thermocouple, a temperature controller, a flow meter, a flow controller and a flow regulating valve, as shown in Figure 6

[0005] ​The existing regulation loop only takes the furnace pressure, oxygen content and furnace temperature as the only feedback signal, while the furnace is a complex system with multiple disturbances, and any external or internal disturbance will directly affect the control effect. The furnace pressure and the combustion air fan also have a disturbance relationship, the furnace oxygen content is affected by the hysteresis of fuel fluctuation, and the furnace temperature and the air volume have a strong coupling relationship. For example, sudden increase or decrease of air volume caused by pressure may cause changes in combustion efficiency, changes in flue gas volume affecting the pressure change of the furnace, etc. By adjusting the fuel quantity, combustion air fan frequency and induced draft fan frequency according to the deviations of temperature, pressure and oxygen content, the system may be over-regulated or lagged. Moreover, the control scheme does not filter the parameters, the sensor has jitter, instantaneous airflow impact, and the detection value has instantaneous jump, which may cause frequent oscillation of the control command. At the same time, the input quantity of waste gas also consumes or generates heat, which interferes with the control of the furnace temperature, pressure and oxygen content, etc. SUMMARY

[0006] To solve the above technical problems, the present application provides a kind of incinerator furnace pressure, oxygen content and temperature automatic control method and system, which compensates, corrects and optimizes the measured values of incinerator furnace pressure, oxygen content and temperature by introducing feedforward parameters, to realize the accurate regulation of incinerator furnace pressure, oxygen content and temperature.

[0007] To achieve the above technical effects, the present application adopts the following technical solutions:

[0008] One of the purposes of the present application is to provide an automatic control method for incinerator furnace pressure, oxygen content and temperature, which comprises:

[0009] The measured values of the pressure, oxygen content and temperature of the incinerator furnace are filtered to obtain stable measured values;

[0010] The stable measured values and set values are subjected to PID processing to obtain PID output values;

[0011] The feedforward parameters are optimized to obtain feedforward parameter adjustment instructions;

[0012] The PID output values are corrected using the feedforward parameter adjustment instructions to obtain final adjustment instructions.

[0013] As a preferred technical solution of the present application, the filtering method comprises inertia filtering.

[0014] As a preferred technical solution of the present application, the feedforward parameter of the incinerator furnace pressure is the combustion air frequency.

[0015] Preferably, the optimization method of the combustion air frequency comprises performing a broken line function processing on the test value of the combustion air frequency to obtain the feedforward parameter adjustment instruction of the incinerator furnace pressure.

[0016] As a preferred technical solution of the present invention, the feedforward parameter adjustment command of the incinerator pressure is added to the PID output value of the incinerator pressure to obtain the final adjustment command of the induced draft fan frequency.

[0017] As a preferred technical solution of the present invention, the feedforward parameters for the oxygen content in the incinerator are the theoretical value command of fuel and the measured value of fuel gas.

[0018] Preferably, the optimization processing method for the theoretical fuel value command and the measured fuel gas value includes performing inertial filtering on the theoretical fuel value command and the measured fuel gas value, comparing and selecting the larger value of the theoretical fuel value command and the measured fuel gas value, and then processing with a piecewise linear function to obtain the feedforward parameter adjustment command for the oxygen content in the incinerator.

[0019] As a preferred technical solution of the present invention, the feedforward parameter adjustment command of the oxygen content in the incinerator is multiplied by the PID output value of the oxygen content in the incinerator to obtain the final adjustment command of the combustion aid frequency.

[0020] As a preferred technical solution of the present invention, the feedforward parameters for the incinerator temperature are the combustion air measurement value and the waste gas volume measurement value.

[0021] Preferably, the optimization processing method for the combustion air measurement value includes performing inertial filtering on the combustion air measurement value to obtain the first feedforward parameter adjustment command for the incinerator temperature.

[0022] Preferably, the optimization processing method for the exhaust gas volume measurement value includes performing inertial filtering on the exhaust gas volume measurement value, followed by piecewise linear function processing, to obtain the first feedforward parameter adjustment command for the incinerator temperature.

[0023] As a preferred technical solution of the present invention, the PID output value of the incinerator temperature is processed by a piecewise linear function, multiplied by the first feedforward parameter adjustment command of the incinerator temperature, and then added to the second feedforward parameter adjustment command of the incinerator temperature to obtain the theoretical fuel value command.

[0024] Preferably, the theoretical fuel value command and the measured fuel gas value after inertial filtering are subjected to PID processing to obtain the final adjustment command of the fuel regulating valve.

[0025] The second objective of this invention is to provide an automatic control system for the pressure, oxygen content, and temperature of an incinerator furnace, which is used in the automatic control method for the pressure, oxygen content, and temperature of the incinerator furnace provided in the first objective.

[0026] As a preferred technical solution of the present invention, the automatic control system includes at least three pressure, oxygen content or temperature sensors. The sensors are independently connected to the data input terminal of the measurement value receiving and processing module. The data output terminal of the measurement value receiving and processing module is connected to the data input terminal of the filtering module. The data output terminal of the filtering module is connected to the data input terminal of the PID module. The data output terminal of the PID module is connected to the data input terminal of the adjustment command correction module.

[0027] The automatic control system includes a feedforward parameter sensor. The data output terminal of the feedforward parameter sensor is connected to the data input terminal of the feedforward parameter optimization module, and the data output terminal of the feedforward parameter optimization module is connected to the data input terminal of the adjustment command correction module.

[0028] Compared with the prior art, the present invention has at least the following beneficial effects:

[0029] (1) This invention provides an automatic control method and system for incinerator furnace pressure, oxygen content and temperature. The method and system have steady-state accuracy, high dynamic response and fast response. Through feedforward compensation, it can respond in advance to the disturbance of furnace pressure caused by changes in air supply, so as to reduce the dynamic deviation of pressure during load change and avoid large fluctuations caused by the lag adjustment of traditional feedback control. It can effectively prevent the production risk of excessive internal furnace pressure and stabilize furnace pressure to create good conditions for fuel and air mixing and combustion.

[0030] (2) The present invention provides an automatic control method and system for incinerator pressure, oxygen content and temperature. The method and system can realize real-time monitoring and automatic adjustment of oxygen content, replace manual adjustment, avoid the problems of adjustment lag and large error, and greatly improve control accuracy; reduce the workload of operators, reduce the risk of human error, and ensure production continuity; accurately control oxygen content to keep the ratio of fuel and air volume at the best state, avoid incomplete combustion due to low oxygen content; and avoid excessive oxygen content to prevent excess air from taking away a large amount of heat and increasing flue gas heat loss.

[0031] (3) The present invention provides an automatic control method and system for incinerator pressure, oxygen content and temperature. The method and system significantly reduce furnace temperature fluctuations and overcome the defects of large lag in traditional pure feedback control. The feedforward link predicts disturbances and acts in advance, making the system respond more timely to changes in fuel quantity, combustion air and other factors. By accurately matching fuel and combustion air and supplying fuel on demand, excessive fuel input or ineffective combustion is avoided, thus achieving efficient energy utilization. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of an automatic control system for incinerator furnace pressure provided for a specific embodiment of the present invention.

[0033] Figure 2This is a schematic diagram of an automatic control system for oxygen content in an incinerator furnace, provided for a specific embodiment of the present invention.

[0034] Figure 3 This is a schematic diagram of an automatic temperature control system for an incinerator furnace, provided for a specific embodiment of the present invention.

[0035] Figure 4 This is a schematic diagram of the structure of an automatic control system for incinerator pressure in the prior art.

[0036] Figure 5 This is a schematic diagram of the structure of an automatic control system for oxygen content in an incinerator in the prior art.

[0037] Figure 6 This is a schematic diagram of the structure of an automatic temperature control system for an incinerator furnace in the prior art.

[0038] Figure 7 The diagram shows the control results of the automatic pressure control method for the incinerator furnace provided in Example 1.

[0039] Figure 8 The diagram shows the control results of the automatic oxygen content control method in the incinerator provided in Example 2.

[0040] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims. Detailed Implementation

[0041] The technical solution of this application will be further described below through specific implementation methods.

[0042] This invention provides an automatic control method for incinerator furnace pressure, oxygen content, and temperature, the automatic control method comprising:

[0043] The measured values ​​of pressure, oxygen content and temperature in the incinerator were filtered to obtain stable measured values;

[0044] The PID output value is obtained by performing PID processing on the stable measured value and the set value;

[0045] The feedforward parameters are optimized to obtain the feedforward parameter adjustment command;

[0046] The PID output value is corrected using feedforward parameter adjustment instructions to obtain the final adjustment instructions.

[0047] In one specific embodiment of the present invention, the filtering method includes inertial filtering.

[0048] In one specific embodiment of this invention, inertial filtering, also known as first-order hysteresis filtering, is a digital filtering algorithm that mimics the characteristics of an RC low-pass filter. Its core principle is to achieve signal filtering by weighted averaging of the current sampled value and the previous filtered output value using a recursive formula. The specific filtering algorithm can be adjusted based on the above theory, according to different models and operating conditions of the incinerator, and is not specifically limited here.

[0049] In this invention, the measured values ​​of pressure, oxygen content and temperature in the incinerator are processed by inertial filtering (LEAD LAG) to filter out high-frequency noise in the field signals (such as instantaneous fluctuations in airflow and sensor measurement interference), making the pressure feedback signal smoother and more stable, avoiding malfunctions in the control algorithm due to false fluctuations, and improving the stability of the control process.

[0050] In one specific embodiment of the present invention, the feedforward parameter of the incinerator furnace pressure is the combustion air frequency.

[0051] In one specific embodiment of the present invention, the method for optimizing the combustion air frequency includes performing a piecewise linear function processing on the test value of the combustion air frequency to obtain the feedforward parameter adjustment command for the incinerator pressure.

[0052] In one specific embodiment of the present invention, the function f(x) used in the piecewise linear function processing calculates the change in the induced draft fan based on the change in the combustion air frequency under various operating conditions.

[0053] In one specific embodiment of the present invention, the feedforward parameter adjustment command of the incinerator pressure is added to the PID output value of the incinerator pressure to obtain the final adjustment command of the induced draft fan frequency.

[0054] In this invention, the deviation between the furnace pressure setpoint and the filtered measured value is the core. A PID controller generates a basic adjustment quantity to ensure that the furnace pressure eventually stabilizes at the setpoint, achieving closed-loop control for deviation correction and guaranteeing steady-state accuracy. The combustion fan frequency is introduced as a feedforward signal and processed using a function f(x) (based on the process correlation setting of combustion air flow rate, furnace pressure, and induced draft fan frequency requirements). This proactively compensates for the disturbance to furnace pressure caused by changes in the combustion fan frequency, overcoming the lag in pressure control and significantly improving the system's dynamic response speed.

[0055] In this invention, the coordination of combustion air frequency feedforward and PID output feedback is achieved through the piecewise linear function f(x) and addition operation: the feedforward signal is adapted to the process correlation of combustion air fan-induced draft fan by f(x), and then added to the feedback adjustment amount, so that the "induced draft fan frequency adjustment command" not only responds to pressure deviation, but also responds to combustion air disturbance in advance, and is more in line with the dynamic change characteristics of actual furnace pressure.

[0056] In one specific embodiment of the present invention, the feedforward parameters for the oxygen content in the incinerator are the theoretical fuel value command and the measured fuel gas value.

[0057] In one specific embodiment of the present invention, the optimization processing method for the theoretical fuel value command and the measured fuel gas value includes performing inertial filtering on the theoretical fuel value command and the measured fuel gas value, comparing and selecting the larger value of the theoretical fuel value command and the measured fuel gas value, and then processing through a piecewise linear function to obtain the feedforward parameter adjustment command for the oxygen content in the incinerator.

[0058] In one specific embodiment of the present invention, the feedforward parameter adjustment command for the oxygen content in the incinerator is multiplied by the PID output value of the oxygen content in the incinerator to obtain the final adjustment command for the combustion aid frequency.

[0059] In this invention, the deviation between the set value of oxygen content in the furnace and the actual value after filtering is the core. A basic adjustment quantity is generated by a PID controller, and then the process correlation of "oxygen content deviation - combustion air correction" is adapted by a piecewise linear function f(x) to output the oxygen content correction coefficient, thereby realizing the dynamic deviation correction of oxygen content on combustion air.

[0060] In this invention, the theoretical fuel value command and the measured fuel gas value are respectively subjected to inertial filtering (LEAD LAG) to eliminate fuel signal fluctuations, and then processed by function f(x) to adapt to the process correlation of "fuel quantity - combustion air demand", converting the fuel quantity into the basic value of combustion air frequency demand.

[0061] In this invention, the larger value between the theoretical fuel value command and the measured fuel gas value is compared to ensure that the combustion air volume is not lower than the minimum requirement for complete fuel combustion, thus prioritizing combustion safety and preventing incomplete combustion of fuel due to insufficient combustion air.

[0062] In this invention, the feedforward-feedback collaborative calculation and precise execution multiply the maximum value after fuel processing by the oxygen correction coefficient to generate a combustion fan frequency adjustment command. This collaboration achieves the dual goals of complete fuel combustion and stable oxygen content by both pre-matching the demand for combustion air due to fuel changes through feedforward and dynamically correcting oxygen content deviations through feedback.

[0063] In this invention, the oxygen content is reasonably reduced (e.g., controlled at 2%~4%) to reduce nitrogen oxides (NOx) generated by excess air. x This process generates oxygen while avoiding pollutants such as carbon monoxide (CO) and carbon oxides produced by incomplete combustion. Under certain operating conditions, precise oxygen content control can directly bring pollutants to compliance with standards, reducing treatment costs. If the oxygen content is out of control (e.g., too high), it will significantly increase the investment in flue gas treatment, while precise control can directly save this cost. It also ensures equipment safety and extends its service life. Stable oxygen content can prevent slagging and carbon buildup in the flue gas duct caused by incomplete combustion, as well as secondary combustion at the tail end (risk of explosion).

[0064] In one specific embodiment of the present invention, the feedforward parameters for the incinerator temperature are the combustion air measurement value and the exhaust gas volume measurement value.

[0065] In one specific embodiment of the present invention, the optimization processing method for combustion air measurement values ​​includes performing inertial filtering on the combustion air measurement values ​​to obtain a first feedforward parameter adjustment command for the incinerator temperature.

[0066] In one specific embodiment of the present invention, the optimization processing method for the waste gas volume measurement value includes performing inertial filtering on the waste gas volume measurement value, and then performing piecewise linear function processing to obtain the second feedforward parameter adjustment command for the incinerator temperature.

[0067] In one specific embodiment of the present invention, the PID output value of the incinerator temperature is processed by a piecewise linear function, multiplied by the first feedforward parameter adjustment command of the incinerator temperature, and then added to the second feedforward parameter adjustment command of the incinerator temperature to obtain the fuel theoretical value command.

[0068] In one specific embodiment of the present invention, the theoretical fuel value command and the fuel gas measurement value after inertial filtering are subjected to PID processing to obtain the final adjustment command of the fuel regulating valve.

[0069] In this invention, the measured values ​​of combustion-related parameters such as combustion air and exhaust gas volume are introduced to compensate for their impact on the combustion process in advance (e.g., insufficient combustion air will lead to incomplete fuel combustion, and the fuel quantity needs to be adjusted in advance), overcoming the disadvantage of large furnace temperature lag and greatly improving the dynamic response speed of the system.

[0070] In this invention, the measured exhaust gas value, after being processed by f(x) (which reflects the nonlinear relationship between exhaust gas volume, combustion efficiency, and fuel demand), is multiplied by the processed signal from the feedback PID output to reflect the proportional impact of exhaust gas volume on fuel demand. The filtered value of the combustion air is added to the above product to reflect the process requirement that the combustion air and fuel must be coordinated in a proportional manner. This calculation method makes the theoretical fuel value command more closely match the dynamic characteristics of actual combustion.

[0071] This invention achieves efficient energy utilization by precisely matching fuel and combustion air, and supplying fuel on demand, thus avoiding excessive fuel input or ineffective combustion. For various types of disturbances such as fuel gas fluctuations, combustion air changes, and abnormal exhaust gas volume, the feedforward stage suppresses measurable and large-amplitude disturbances, while the feedback stage eliminates unmeasurable and small-amplitude disturbances. This allows the system to operate stably even in complex industrial environments (such as those with frequent changes in furnace operating conditions), demonstrating significantly better anti-interference capabilities and robustness than single-loop control. Its application in furnaces (such as tubular furnaces and industrial boilers) in industries like chemical, petroleum, and metallurgy not only improves product quality but also reduces equipment wear and tear, while saving labor costs, achieving comprehensive benefits of improved quality, reduced consumption, and increased efficiency.

[0072] This invention provides an automatic control system for incinerator pressure, oxygen content, and temperature. The automatic control system includes at least three pressure, oxygen content, or temperature sensors. Each sensor is independently connected to the data input terminal of a measurement value receiving and processing module. The data output terminal of the measurement value receiving and processing module is connected to the data input terminal of a filtering module. The data output terminal of the filtering module is connected to the data input terminal of a PID module. The data output terminal of the PID module is connected to the data input terminal of a regulation command correction module.

[0073] The automatic control system includes a feedforward parameter sensor. The data output terminal of the feedforward parameter sensor is connected to the data input terminal of the feedforward parameter optimization module, and the data output terminal of the feedforward parameter optimization module is connected to the data input terminal of the adjustment command correction module.

[0074] In one specific embodiment of the present invention, at least three pressure sensors, at least three oxygen content sensors, and at least three temperature sensors are included to measure the pressure, oxygen content, and temperature of each area of ​​the furnace in real time. This achieves redundancy and solves the problems of insufficient representativeness of single measuring points and susceptibility to local interference. The measured values ​​of furnace pressure, oxygen content, and temperature more comprehensively reflect the overall pressure condition of the furnace and provide reliable core feedback for control.

[0075] In one specific embodiment of the present invention, an automatic control system for incinerator furnace pressure has the following structure: Figure 1 As shown, the automatic control system includes at least three pressure sensors. Each sensor is independently connected to the data input terminal of the SELM module. The data output terminal of the SELM module is connected to the data input terminal of the inertial filter module. The data output terminal of the inertial filter module is connected to the data input terminal of the PID module. The data output terminal of the PID module is connected to the data input terminal of the adjustment command correction module. The combustion fan is equipped with a data output terminal for outputting the combustion fan frequency. The data output terminal of the combustion fan is connected to the data input terminal of the piecewise linear function processing module. The data output terminal of the piecewise linear function processing module is connected to the data input terminal of the adjustment command correction module. The adjustment command correction module outputs the final induced draft fan frequency adjustment command.

[0076] In one specific embodiment of the present invention, an automatic control system for oxygen content in an incinerator furnace has the following structure: Figure 2As shown, the automatic control system includes at least three oxygen content sensors. Each sensor is independently connected to the data input terminal of the SELM module for measuring values. The data output terminal of the SELM module is connected to the data input terminal of the first inertial filter module. The data output terminal of the first inertial filter module is connected to the data input terminal of the PID module. The data output terminal of the PID module is connected to the data input terminal of the first piecewise linear function processing module. The data output terminal of the first piecewise linear function processing module is connected to the data input terminal of the adjustment command correction module.

[0077] The data output terminal of the fuel theoretical value output module is connected to the data input terminal of the second inertial filter module. The data output terminals of each fuel gas sensor are connected to the data input terminal of the third inertial filter module. The data output terminals of the second and third inertial filter modules are independently connected to the data input terminal of the MAX module. The data output terminal of the MAX module is connected to the data input terminal of the second piecewise linear function processing module. The data output terminal of the second piecewise linear function processing module is connected to the data input terminal of the command correction module. The command correction module outputs the final combustion fan frequency adjustment command.

[0078] In one specific embodiment of the present invention, an automatic control system for incinerator furnace temperature has the following structure: Figure 3 As shown, the automatic control system includes at least three temperature sensors. Each sensor is independently connected to the data input terminal of the SELM module. The data output terminal of the SELM module is connected to the data input terminal of the first inertial filter module. The data output terminal of the first inertial filter module is connected to the data input terminal of the first PID module. The data output terminal of the first PID module is connected to the data input terminal of the first piecewise linear function processing module. The data output terminal of the first piecewise linear function processing module is connected to the data input terminal of the first adjustment command correction module. The data output terminal of the first adjustment command correction module is connected to the data input terminal of the second adjustment command correction module. The data output terminal of the second adjustment command correction module is connected to the data input terminal of the second PID module.

[0079] The data output terminal of the combustion air sensor is connected to the data input terminal of the second inertial filter module; the data output terminal of the exhaust gas volume sensor is connected to the data input terminal of the third inertial filter module; and the data output terminal of the fuel gas sensor is connected to the data input terminal of the fourth inertial filter module. The data output terminal of the third inertial filter module is connected to the data input terminal of the second piecewise linear function processing module; the data output terminal of the second piecewise linear function processing module is connected to the data input terminal of the second adjustment command correction module; the data output terminal of the second inertial filter module is connected to the data input terminal of the first adjustment command correction module; and the data output terminal of the fourth inertial filter module is connected to the data input terminal of the second PID module. The second PID module outputs the final fuel regulating valve command.

[0080] Example 1

[0081] This embodiment provides an automatic control method for incinerator furnace pressure. This automatic control method uses... Figure 1 The automatic control system for incinerator furnace pressure shown includes the following automatic control methods:

[0082] The measured values ​​from the three pressure sensors in the incinerator are filtered and then processed by the SELM module and the inertial filter module to obtain stable measured values.

[0083] The PID output value is obtained by performing PID processing on the stable measured value and the set value in the PID module.

[0084] The combustion fan frequency is optimized using a piecewise linear function processing module to obtain feedforward parameter adjustment instructions;

[0085] In the adjustment command correction module, the feedforward parameter adjustment command is summed with the PID output value to obtain the final adjustment command for the induced draft fan frequency. The adjustment is as follows: Figure 7 As shown.

[0086] Example 2

[0087] This embodiment provides an automatic control method for oxygen content in an incinerator furnace. This automatic control method uses... Figure 2 The automatic control system for oxygen content in the incinerator shown includes the following automatic control methods:

[0088] The measured values ​​from three oxygen content sensors in the incinerator are filtered and processed by the SELM module and the inertial filter module to obtain stable measured values.

[0089] The PID output value is obtained by performing PID processing on the stable measured value and the set value in the PID module. The first piecewise linear function processing module is then used to perform a discount function processing on the PID output value.

[0090] The second and third inertial filtering modules are used to perform inertial filtering on the theoretical fuel value command and the measured fuel gas value. The resulting data is compared and selected in the MAX module, and the larger value of the theoretical fuel value command and the measured fuel gas value is then processed by the discount function in the second piecewise linear function processing module.

[0091] The final adjustment command for the combustion fan frequency is obtained by multiplying the output values ​​of the first and second piecewise linear function processing modules in the adjustment command correction module. The adjustment is as follows: Figure 8 As shown.

[0092] Example 3

[0093] This embodiment provides an automatic control method for incinerator furnace temperature. This automatic control method uses... Figure 2 The automatic control system for incinerator temperature shown includes the following automatic control methods:

[0094] The measured values ​​from the three temperature sensors in the incinerator are filtered and then processed by the SELM module to obtain stable measured values.

[0095] The stable measured values ​​are processed by the first coherent filtering module and the set value are processed by the first PID module to obtain the PID output value. The first piecewise linear function processing module is used to process the PID output value by the discount function.

[0096] The data from the combustion wind sensor is processed by the second inertial filtering module and then multiplied with the output value of the first piecewise linear function processing module in the first adjustment command correction module.

[0097] The data from the exhaust gas volume sensor is processed by the third inertial filtering module and then by the second piecewise linear function processing module. Its output value is added to the output value of the first adjustment command correction module in the second adjustment command correction module.

[0098] The data from the fuel gas sensor is processed by the fourth inertial filter module and then combined with the output value of the second adjustment command correction module in the second PID module to obtain the final fuel regulating valve command. The incinerator temperature can be stably controlled at around 1050℃.

[0099] The results of automatic control of incinerator furnace pressure, oxygen content and temperature in Examples 1-3 show that the method and system have steady-state accuracy, high dynamic response and fast response. Through feedforward compensation, it can anticipate the disturbance of furnace pressure caused by changes in air supply, reduce the dynamic pressure deviation during load changes and avoid large fluctuations caused by the lag adjustment of traditional feedback control. It can effectively prevent the production risk of excessive internal furnace pressure and create favorable conditions for fuel and air mixing and combustion by stabilizing the furnace pressure.

[0100] The results of automatic control of incinerator pressure, oxygen content, and temperature in Examples 1-3 show that the method and system can achieve real-time monitoring and automatic adjustment of oxygen content, replacing manual adjustment, avoiding problems of adjustment lag and large errors, and significantly improving control accuracy; reducing the workload of operators, reducing the risk of human error, and ensuring production continuity; accurately controlling oxygen content to keep the fuel and air volume ratio at the optimal state, avoiding incomplete combustion due to excessively low oxygen content; and avoiding excessively high oxygen content, which would cause excess air to carry away a large amount of heat and increase flue gas heat loss.

[0101] The results of automatic control of incinerator pressure, oxygen content and temperature in Examples 1-3 show that the method and system significantly reduce furnace temperature fluctuations, overcome the shortcomings of traditional pure feedback control with large lag, and the feedforward link predicts disturbances and acts in advance, making the system respond more timely to changes in fuel quantity, combustion air and other factors; by accurately matching fuel and combustion air and supplying fuel on demand, excessive fuel input or ineffective combustion is avoided, thus achieving efficient energy utilization.

Claims

1. A method for automatically controlling the pressure, oxygen content, and temperature of an incinerator furnace, characterized in that, The automatic control method includes: The measured values ​​of pressure, oxygen content, and temperature in the incinerator are filtered to obtain stable measured values. By performing PID processing on the stable measured value and the set value, the PID output value is obtained; The feedforward parameters are optimized to obtain the feedforward parameter adjustment command; The PID output value is corrected using the feedforward parameter adjustment command to obtain the final adjustment command.

2. The automatic control method according to claim 1, characterized in that, The filtering method includes inertial filtering.

3. The automatic control method according to claim 1, characterized in that, The feedforward parameter for the incinerator furnace pressure is the combustion air frequency. The optimization method for the combustion air frequency includes processing the test value of the combustion air frequency using a piecewise linear function to obtain the feedforward parameter adjustment command for the incinerator pressure.

4. The automatic control method according to claim 3, characterized in that, The feedforward parameter adjustment command for the incinerator pressure is added to the PID output value of the incinerator pressure to obtain the final adjustment command for the induced draft fan frequency.

5. The automatic control method according to claim 1, characterized in that, The feedforward parameter for the oxygen content in the incinerator is the theoretical fuel value command and the measured fuel gas value; The optimization processing method for the theoretical fuel value command and the measured fuel gas value includes performing inertial filtering on the theoretical fuel value command and the measured fuel gas value, comparing and selecting the larger value of the theoretical fuel value command and the measured fuel gas value, and then processing with a piecewise linear function to obtain the feedforward parameter adjustment command for the oxygen content in the incinerator.

6. The automatic control method according to claim 5, characterized in that, The feedforward parameter adjustment command for the oxygen content in the incinerator is multiplied by the PID output value of the oxygen content in the incinerator to obtain the final adjustment command for the combustion fan frequency.

7. The automatic control method according to claim 1, characterized in that, The feedforward parameters for the incinerator temperature are the combustion air measurement value and the exhaust gas volume measurement value. The optimization processing method for the combustion air measurement value includes performing inertial filtering on the combustion air measurement value to obtain a first feedforward parameter adjustment command for the incinerator temperature. The optimization processing method for the waste gas volume measurement value includes performing inertial filtering on the waste gas volume measurement value, followed by piecewise linear function processing to obtain the first feedforward parameter adjustment command for the incinerator temperature.

8. The automatic control method according to claim 7, characterized in that, The PID output value of the incinerator temperature is processed by a piecewise linear function, multiplied by the second feedforward parameter adjustment command of the incinerator temperature, and then added to the second feedforward parameter adjustment command of the incinerator temperature to obtain the theoretical fuel value command. The theoretical fuel value command and the measured fuel gas value after inertial filtering are subjected to PID processing to obtain the final adjustment command of the fuel regulating valve.

9. An automatic control system for incinerator pressure, oxygen content, and temperature, characterized in that, The automatic control system is used in the automatic control method for incinerator pressure, oxygen content and temperature as described in any one of claims 1-8.

10. The automatic control system according to claim 9, characterized in that, The automatic control system includes at least three pressure, oxygen content, or temperature sensors. Each sensor is independently connected to the data input terminal of the measurement value receiving and processing module. The data output terminal of the measurement value receiving and processing module is connected to the data input terminal of the filtering module. The data output terminal of the filtering module is connected to the data input terminal of the PID module. The data output terminal of the PID module is connected to the data input terminal of the adjustment command correction module. The automatic control system includes a feedforward parameter sensor, the data output terminal of which is connected to the data input terminal of the feedforward parameter optimization module, and the data output terminal of the feedforward parameter optimization module is connected to the data input terminal of the adjustment command correction module.

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