Frequency converter control method and device for desulfurization fan of heating furnace

Abstract

The invention discloses a frequency converter control method and device for a heating furnace desulfurization fan, and relates to the technical field of heating furnaces. The operation frequency target value corresponding to the gas flow measured value is determined according to the preset corresponding relation between the operation frequency of the frequency converter and the gas flow of the heating furnace, and the operation frequency of the frequency converter is controlled based on the operation frequency target value. As the operation frequency target value is the frequency converter operation frequency capable of keeping the hearth pressure of the heating furnace basically constant under the current gas flow, the hearth pressure fluctuation of the heating furnace can be reduced by controlling the operation frequency of the frequency converter based on the operation frequency target value.

Description

Technical Field

[0001] The present invention relates to the technical field of heating furnaces, and in particular to a frequency converter control method and device for a desulfurization fan of a heating furnace. Background Art

[0002] In the metallurgical industry, the coal gas generated by the combustion of the heating furnace will be desulfurized by the desulfurization tower of the desulfurization system. The desulfurized coal gas will then be discharged into the atmosphere through the desulfurization fan of the desulfurization system. The desulfurization fan is driven by a frequency converter. The higher the frequency of the frequency converter, the greater the suction force of the desulfurization fan. At present, the frequency converter frequency of the desulfurization fan is constant, that is, the suction force of the desulfurization fan is constant. If the suction force is constant, there will be problems such as insufficient exhaust and too fast exhaust. Insufficient exhaust will cause the furnace pressure of the heating furnace to be too high, and too fast exhaust will cause the furnace pressure of the heating furnace to be too low, that is, it will cause large fluctuations in the furnace pressure and cannot meet the control requirements of the process. Summary of the invention

[0003] The present invention solves the technical problem of how to reduce the furnace pressure fluctuation of the heating furnace by providing a frequency converter control method and device for a heating furnace desulfurization fan.

[0004] On the one hand, the present invention provides the following technical solutions:

[0005] A frequency converter control method for a heating furnace desulfurization fan, comprising:

[0006] Obtain the measured value of the gas flow rate in the heating furnace;

[0007] According to a preset corresponding relationship between the operating frequency and the gas flow rate, determining a target value of the operating frequency corresponding to the measured value of the gas flow rate; the operating frequency is positively correlated with the gas flow rate;

[0008] The operating frequency of the frequency converter of the desulfurization blower is controlled based on the target value of the operating frequency.

[0009] In some implementations, the preset corresponding relationship includes a preset relationship table or a preset relationship expression;

[0010] The preset relationship table includes a plurality of gas flow rates and the operating frequencies corresponding to the plurality of gas flow rates respectively;

[0011] In the preset relationship, the gas flow rate is the independent variable, and the operating frequency is the dependent variable.

[0012] In some embodiments, before determining the target value of the operating frequency corresponding to the measured value of the gas flow rate according to the preset corresponding relationship between the operating frequency and the gas flow rate, the method further includes:

[0013] Obtaining the pressure difference between the inlet pressure and the outlet pressure of the desulfurization tower; the operating frequency is positively correlated with the pressure difference;

[0014] The preset corresponding relationship corresponding to the pressure difference is determined.

[0015] In some embodiments, determining the preset corresponding relationship corresponding to the pressure difference includes:

[0016] Determining a preset pressure interval within which the pressure difference lies;

[0017] The preset corresponding relationship corresponding to the preset pressure interval is determined.

[0018] In some embodiments, controlling the operating frequency of the frequency converter of the desulfurization blower based on the target value of the operating frequency includes:

[0019] A frequency difference between the operating frequency of the frequency converter and a target value of the operating frequency is controlled to be lower than a preset threshold, and the preset threshold is greater than zero.

[0020] In some implementations, controlling the frequency difference between the operating frequency of the frequency converter and the target value of the operating frequency to be lower than a preset threshold comprises:

[0021] A frequency difference between the operating frequency of the inverter and a target value of the operating frequency is controlled to be zero.

[0022] In some embodiments, the controlling the operating frequency of the frequency converter of the desulfurization blower based on the target value of the operating frequency includes:

[0023] If the target value of the operating frequency is higher than a first frequency threshold, controlling the operating frequency of the inverter based on the first frequency threshold;

[0024] If the target value of the operating frequency is lower than a second frequency threshold, controlling the operating frequency of the inverter based on the second frequency threshold;

[0025] If the target value of the operating frequency is between the second frequency threshold and the first frequency threshold, controlling the operating frequency of the inverter based on the operating frequency;

[0026] The first frequency threshold is greater than the second frequency threshold.

[0027] On the other hand, the present invention also provides the following technical solutions:

[0028] A frequency converter control device for a heating furnace desulfurization fan, comprising:

[0029] An acquisition module is used to obtain the measured value of the gas flow rate in the heating furnace;

[0030] a determination module, configured to determine a target value of the operating frequency corresponding to the measured value of the gas flow rate according to a preset corresponding relationship between the operating frequency and the gas flow rate; the operating frequency is positively correlated with the gas flow rate;

[0031] A control module is used to control the operating frequency of the frequency converter of the desulfurization fan based on the target value of the operating frequency.

[0032] On the other hand, the present invention also provides the following technical solutions:

[0033] A computer device comprises a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of any one of the above-mentioned frequency converter control methods for a heating furnace desulfurization fan.

[0034] On the other hand, the present invention also provides the following technical solutions:

[0035] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of any of the above-mentioned frequency converter control methods for a heating furnace desulfurization fan.

[0036] One or more technical solutions provided by the present invention have at least the following technical effects or advantages:

[0037] The present invention determines the operating frequency target value corresponding to the actual gas flow rate according to the preset corresponding relationship between the inverter operating frequency and the heating furnace gas flow rate, and controls the operating frequency of the inverter based on the operating frequency target value. Since the operating frequency target value is the inverter operating frequency that can keep the furnace pressure of the heating furnace basically constant under the current gas flow rate, controlling the operating frequency of the inverter based on the operating frequency target value can reduce the furnace pressure fluctuation of the heating furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0039] Figure 1 It is a flow chart of a frequency converter control method of a heating furnace desulfurization fan in an embodiment of the present invention;

[0040] Figure 2 It is a schematic diagram of a frequency converter control device for a desulfurization fan of a heating furnace in an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The embodiment of the present invention solves the technical problem of how to reduce the furnace pressure fluctuation of the heating furnace by providing a frequency converter control method and device for a desulfurization fan of the heating furnace.

[0042] In order to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0043] like Figure 1 As shown, the inverter control method of the heating furnace desulfurization fan according to the embodiment of the present invention includes:

[0044] Step S1, obtaining the measured value of the gas flow rate in the heating furnace;

[0045] In some embodiments, the gas flow rate can be detected by a gas flow meter; it is understood that, in order to keep the furnace pressure of the heating furnace constant, the greater the gas flow rate in the heating furnace, the greater the suction force of the desulfurization fan should be, and the smaller the gas flow rate in the heating furnace, the smaller the suction force of the desulfurization fan should be;

[0046] Step S2, determining a target value of the operating frequency corresponding to the measured value of the gas flow rate according to a preset corresponding relationship between the operating frequency and the gas flow rate; the operating frequency is positively correlated with the gas flow rate;

[0047] Among them, the preset corresponding relationship can be established in advance, for example, a constant pressure is designed, and the gas flow rate is set to different measured values. For the set multiple gas flow measured values, the operating frequency of the frequency converter is continuously changed to obtain the frequency converter operating frequency that can make the furnace pressure of the heating furnace at the constant pressure, and the frequency converter operating frequency is used as the operating frequency target value corresponding to the gas flow measured value, and then multiple operating frequency target values ​​corresponding to the set multiple gas flow measured values ​​can be obtained; if the number of set gas flow measured values ​​is large and the interval is small, a preset relationship table including multiple gas flow measured values ​​and multiple operating frequency target values ​​corresponding to the gas flow measured values ​​can be established, that is, the preset corresponding relationship can be the preset relationship table; further, multiple gas flow measured values ​​and corresponding operating frequency target values ​​can be fitted to obtain a preset relationship between the operating frequency and the gas flow, in which the gas flow is the independent variable and the operating frequency is the dependent variable, that is, the preset corresponding relationship can be the preset relationship; in some embodiments, the preset relationship can be a linear relationship;

[0048] After obtaining the measured value of the gas flow, the target value of the operating frequency corresponding to the measured value of the gas flow can be found in the preset relationship table, or the measured value of the gas flow can be input into the preset relationship formula to calculate the corresponding target value of the operating frequency;

[0049] Step S3, controlling the operating frequency of the frequency converter of the desulfurization fan based on the target value of the operating frequency;

[0050] In some embodiments, step S3 may include: controlling the frequency difference between the operating frequency of the inverter and the target value of the operating frequency to be lower than a preset threshold, and the preset threshold is greater than zero; the preset threshold is smaller, and in some embodiments, the frequency difference between the operating frequency of the inverter and the target value of the operating frequency can be controlled to be non-zero, that is, controlling the operating frequency of the inverter to be near the target value of the operating frequency; in some embodiments, the frequency difference between the operating frequency of the inverter and the target value of the operating frequency can be controlled to be zero, that is, controlling the operating frequency of the inverter to be the target value of the operating frequency, which can theoretically make the furnace pressure of the heating furnace more constant; since the target value of the operating frequency is the inverter operating frequency that can keep the furnace pressure of the heating furnace basically constant under the current gas flow rate, controlling the operating frequency of the inverter to be near the target value of the operating frequency or to be the target value of the operating frequency can reduce the furnace pressure fluctuation of the heating furnace.

[0051] In the embodiment of the present invention, the factors affecting the gas exhaust effect include not only the fan draft, but also the resistance of the desulfurization tower itself. The greater the resistance of the desulfurization tower itself, the greater the fan draft is required to keep the furnace pressure of the heating furnace constant for the same gas flow; the smaller the resistance of the desulfurization tower itself, the smaller the fan draft is required to keep the furnace pressure of the heating furnace constant for the same gas flow. If the operating frequency of the inverter is determined only according to the gas flow without considering the influence of the desulfurization tower's own resistance, it is not conducive to reducing the furnace pressure fluctuation of the heating furnace. In order to further reduce the furnace pressure fluctuation of the heating furnace, in some embodiments, before step S2, the inverter control method of the heating furnace desulfurization fan may also include: obtaining the pressure difference between the inlet pressure and the outlet pressure of the desulfurization tower; the operating frequency is positively correlated with the pressure difference; and determining the preset corresponding relationship corresponding to the pressure difference. In some embodiments, the determination of the preset corresponding relationship corresponding to the pressure difference may include: determining the preset pressure interval in which the pressure difference is located; and determining the preset corresponding relationship corresponding to the preset pressure interval.

[0052] In some embodiments, pressure detectors may be provided at the inlet and outlet of the desulfurization tower to detect the pressure. The pressure difference between the inlet pressure and the outlet pressure is the difference between the inlet pressure and the outlet pressure. The pressure difference between the inlet pressure and the outlet pressure represents the self-resistance of the desulfurization tower. The greater the pressure difference, the greater the self-resistance of the desulfurization tower. A preset corresponding relationship corresponding to each preset pressure interval may be established in advance. The operating frequency determined according to the preset corresponding relationship is positively correlated with the pressure difference. Thus, the higher the level of the pressure difference, the greater the determined operating frequency, and the greater the suction force of the fan, which is conducive to overcoming the self-resistance of the desulfurization tower and further reducing the furnace pressure fluctuation of the heating furnace.

[0053] For example, the preset pressure interval may include the three pressure intervals of <1000, [1000, 2000], and >2000. If the operating frequency of the frequency converter that can keep the furnace pressure of the heating furnace constant is 10 when the pressure difference is <1000Pa and the actual measured value of the gas flow is 15000, and the operating frequency of the frequency converter that can keep the furnace pressure of the heating furnace constant is 30 when the actual measured value of the gas flow is 35000, then the linear relationship y=0.001x-5 corresponding to the preset pressure interval of <1000 can be determined based on the two points (15000, 10) and (35000, 30), where x is the gas flow and y is the operating frequency; if the operating frequency of the frequency converter that can keep the furnace pressure of the heating furnace constant is 10 when the pressure difference is [1000, 2000] and the actual measured value of the gas flow is 15000, and the operating frequency of the frequency converter that can keep the furnace pressure of the heating furnace constant is 30 When the actual measured value of the gas flow rate is 35000, the inverter operating frequency that can keep the furnace pressure of the heating furnace constant is 35. The linear relationship y=0.00125x-8.75 corresponding to the preset pressure range of [1000,2000] can be determined based on the two points (15000, 10) and (35000, 35); if the inverter operating frequency that can keep the furnace pressure of the heating furnace constant when the pressure difference is greater than 2000Pa and the actual measured value of the gas flow rate is 15000 is 15, and the inverter operating frequency that can keep the furnace pressure of the heating furnace constant when the actual measured value of the gas flow rate is 35000 is 40, the linear relationship y=0.00125x-3.75 corresponding to the preset pressure range of greater than 2000 can be determined based on the two points (15000, 15) and (35000, 40).

[0054] In an embodiment of the present invention, in order to avoid abnormal gas flow data or the calculated operating frequency exceeding a reasonable range, it is necessary to limit the operating frequency of the frequency converter, that is, in some embodiments, step S3 may include: if the target value of the operating frequency is higher than the first frequency threshold, the operating frequency of the frequency converter is controlled based on the first frequency threshold; if the target value of the operating frequency is lower than the second frequency threshold, the operating frequency of the frequency converter is controlled based on the second frequency threshold; if the target value of the operating frequency is between the second frequency threshold and the first frequency threshold, the operating frequency of the frequency converter is controlled based on the target value of the operating frequency; the first frequency threshold is greater than the second frequency threshold. In some embodiments, the first frequency threshold may be 48Hz, and the second frequency threshold may be 8Hz. Among them, controlling the operating frequency of the frequency converter based on the first frequency threshold may include: controlling the operating frequency of the frequency converter to be the first frequency threshold. Controlling the operating frequency of the frequency converter based on the second frequency threshold may include: controlling the operating frequency of the frequency converter to be the second frequency threshold. Controlling the frequency of the frequency converter based on the target value of the operating frequency may include: controlling the operating frequency of the frequency converter to be the target value of the operating frequency. Thus, the operating frequency of the frequency converter can be controlled between 8 and 48Hz.

[0055] like Figure 2 As shown, the embodiment of the present invention also provides a frequency converter control device for a heating furnace desulfurization fan, comprising:

[0056] An acquisition module is used to obtain the measured value of the gas flow rate in the heating furnace;

[0057] A determination module, used to determine a target value of the operating frequency corresponding to the measured value of the gas flow rate according to a preset corresponding relationship between the operating frequency and the gas flow rate; the operating frequency is positively correlated with the gas flow rate;

[0058] The control module is used to control the operating frequency of the frequency converter of the desulfurization fan based on the target value of the operating frequency.

[0059] In some implementations, the preset corresponding relationship may include a preset relationship table or a preset relationship expression;

[0060] The preset relationship table includes a plurality of gas flow rates and operating frequencies corresponding to the plurality of gas flow rates;

[0061] In the preset relationship, the gas flow rate is the independent variable and the operating frequency is the dependent variable.

[0062] In some implementations, the acquisition module may also be used to:

[0063] Obtain the pressure difference between the inlet pressure and the outlet pressure of the desulfurization tower; the operating frequency is positively correlated with the pressure difference;

[0064] The determination module can also be used to: determine a preset corresponding relationship corresponding to the pressure difference.

[0065] In some embodiments, the determination module may be specifically used to: determine a preset pressure interval in which the pressure difference is located;

[0066] Determine a preset corresponding relationship corresponding to the preset pressure range.

[0067] In some implementations, the control module may be specifically configured to:

[0068] A frequency difference between an operating frequency of the frequency converter and a target value of the operating frequency is controlled to be lower than a preset threshold value, and the preset threshold value is greater than zero.

[0069] In some implementations, the control module may be specifically configured to:

[0070] The frequency difference between the operating frequency of the inverter and the target value of the operating frequency is controlled to be zero.

[0071] In some implementations, the control module may be specifically configured to:

[0072] If the target value of the operating frequency is higher than the first frequency threshold, controlling the operating frequency of the frequency converter based on the first frequency threshold;

[0073] If the target value of the operating frequency is lower than the second frequency threshold, controlling the operating frequency of the frequency converter based on the second frequency threshold;

[0074] If the target value of the operating frequency is between the second frequency threshold and the first frequency threshold, controlling the operating frequency of the frequency converter based on the operating frequency;

[0075] The first frequency threshold is greater than the second frequency threshold.

[0076] Based on the same inventive concept as the inverter control method for a heating furnace desulfurization fan mentioned above, an embodiment of the present invention also provides a computer device, including a memory, a processor and a computer program stored in the memory, and the processor executes the computer program to implement the steps of any of the inverter control methods for a heating furnace desulfurization fan mentioned above.

[0077] Since the computer device introduced in the embodiment of the present invention is a computer device used to implement the inverter control method for the heating furnace desulfurization fan in the embodiment of the present invention, based on the inverter control method for the heating furnace desulfurization fan introduced in the embodiment of the present invention, the technical personnel of the field can understand the specific implementation of the computer device in the embodiment of the present invention and its various variations, so how the computer device implements the method in the embodiment of the present invention is not described in detail here. As long as the computer device used by the technical personnel of the field to implement the inverter control method for the heating furnace desulfurization fan in the embodiment of the present invention, it belongs to the scope of protection of the present invention.

[0078] Based on the same inventive concept as the inverter control method for a heating furnace desulfurization fan mentioned above, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the inverter control methods for a heating furnace desulfurization fan mentioned above.

[0079] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0080] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer-readable memory produce a product including an instruction device, which implements the functions specified in the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0081] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0082] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0083] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A frequency converter control method for a heating furnace desulfurization fan, characterized in that: include: Obtain the measured value of the gas flow rate in the heating furnace; Determining a target value of the operating frequency corresponding to the measured value of the gas flow rate according to a preset corresponding relationship between the operating frequency and the gas flow rate; The operating frequency is positively correlated with the gas flow rate; The operating frequency of the frequency converter of the desulfurization blower is controlled based on the target value of the operating frequency.

2. The inverter control method for the heating furnace desulfurization fan according to claim 1, characterized in that: The preset corresponding relationship includes a preset relationship table or a preset relationship expression; The preset relationship table includes a plurality of gas flow rates and the operating frequencies corresponding to the plurality of gas flow rates respectively; In the preset relationship, the gas flow rate is the independent variable, and the operating frequency is the dependent variable.

3. The inverter control method for the heating furnace desulfurization fan according to claim 1, characterized in that: Before determining the target value of the operating frequency corresponding to the measured value of the gas flow rate according to the preset corresponding relationship between the operating frequency and the gas flow rate, the method further includes: Obtaining the pressure difference between the inlet pressure and the outlet pressure of the desulfurization tower; the operating frequency is positively correlated with the pressure difference; The preset corresponding relationship corresponding to the pressure difference is determined.

4. The inverter control method for the heating furnace desulfurization fan according to claim 3, characterized in that: The determining the preset corresponding relationship corresponding to the pressure difference includes: Determining a preset pressure interval within which the pressure difference lies; The preset corresponding relationship corresponding to the preset pressure interval is determined.

5. The inverter control method for a heating furnace desulfurization fan according to claim 1, characterized in that: The step of controlling the operating frequency of the frequency converter of the desulfurization fan based on the target value of the operating frequency includes: A frequency difference between the operating frequency of the frequency converter and a target value of the operating frequency is controlled to be lower than a preset threshold, and the preset threshold is greater than zero.

6. The inverter control method for the heating furnace desulfurization fan according to claim 5, characterized in that: The controlling the frequency difference between the operating frequency of the frequency converter and the target value of the operating frequency to be lower than a preset threshold comprises: A frequency difference between the operating frequency of the inverter and a target value of the operating frequency is controlled to be zero.

7. The inverter control method for a heating furnace desulfurization fan according to claim 1, characterized in that: The step of controlling the operating frequency of the frequency converter of the desulfurization fan based on the target value of the operating frequency includes: If the target value of the operating frequency is higher than a first frequency threshold, controlling the operating frequency of the inverter based on the first frequency threshold; If the target value of the operating frequency is lower than a second frequency threshold, controlling the operating frequency of the inverter based on the second frequency threshold; If the target value of the operating frequency is between the second frequency threshold and the first frequency threshold, controlling the operating frequency of the inverter based on the operating frequency; The first frequency threshold is greater than the second frequency threshold.

8. A frequency converter control device for a heating furnace desulfurization fan, characterized in that: include: An acquisition module is used to obtain the measured value of the gas flow rate in the heating furnace; a determination module, configured to determine a target value of the operating frequency corresponding to the measured value of the gas flow rate according to a preset correspondence between the operating frequency and the gas flow rate; The operating frequency is positively correlated with the gas flow rate; A control module is used to control the operating frequency of the frequency converter of the desulfurization fan based on the target value of the operating frequency.

9. A computer device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

Images