Steam drum liquid level control method suitable for peak regulation operation of CFB boiler and related device

Abstract

The invention discloses a steam drum liquid level control method suitable for peak regulation operation of a CFB boiler and a related device, and relates to the field of boilers, and the method comprises the steps that the heat transfer coefficient in the boiler is determined according to the operation parameters of the boiler, and the steam yield of the boiler in the load change period is determined according to the heat transfer coefficient; the water supply amount in the load change time period is obtained, and the water consumption amount caused by the boiler load change is determined based on the steam production amount, the water supply amount and a preset energy balance correction coefficient; adjusting the current total steam yield of the boiler according to the water consumption, determining the current steam drum water supply quantity of the boiler according to the adjusted current total steam yield, and controlling the liquid level of the steam drum according to the current steam drum water supply quantity. When the current steam drum water supply amount is determined, the water consumption amount caused by the boiler load change in the boiler operation process is considered, and the more accurate water consumption amount in the boiler operation process is obtained, so that the more accurate steam drum water supply amount is determined, and the control deviation of the steam drum liquid level is effectively reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of boilers, in particular to a drum level control method suitable for peak shaving operation of a CFB boiler and related device. BACKGROUND

[0002] The CFB boiler is a fuel boiler taking CFB (Circulating Fluidized Bed) as the core technology, and is widely used in the fields of power generation, industrial heating, etc. The drum of the CFB boiler is an important structure of the water circulation system of the CFB boiler. In order to ensure the stable operation of the CFB boiler, the drum level of the CFB boiler needs to be monitored and controlled in real time to avoid damage to related equipment caused by abnormal water level of the CFB boiler. The water circulation system of the CFB boiler is used to heat water into saturated steam, and the drum level refers to the position of the interface between water and saturated steam in the drum.

[0003] The feedwater quantity of the drum can affect the drum level. At present, the control of the feedwater quantity of the drum mainly coarsely adjusts the total steam production quantity of the CFB boiler, and control deviation is prone to exist. SUMMARY

[0004] In view of the above problems, the present application provides a drum level control method suitable for peak shaving operation of a CFB boiler and related device to realize the purpose of reducing the control deviation of the drum level. The specific scheme is as follows:

[0005] The first aspect of the present application provides a drum level control method suitable for peak shaving operation of a CFB boiler, which comprises:

[0006] determining the heat transfer coefficient in the boiler according to the operating parameters of the boiler, and determining the steam production quantity of the boiler in a load change period according to the heat transfer coefficient;

[0007] obtaining the feedwater quantity in the load change period, and determining the consumed water quantity caused by the change of the load of the boiler based on the steam production quantity, the feedwater quantity and a preset energy balance correction coefficient;

[0008] adjusting the current total steam production quantity of the boiler according to the consumed water quantity, and determining the current drum feedwater quantity of the boiler according to the adjusted current total steam production quantity;

[0009] controlling the drum level according to the current drum feedwater quantity.

[0010] In a possible implementation, the determination of the heat transfer coefficient in the boiler according to the operating parameters of the boiler comprises:

[0011] A product of a boiler fuel ash formation characteristic coefficient, a boiler geometric characteristic coefficient, a boiler operation fluidization velocity and a boiler operation circulating ash concentration is taken as the heat transfer coefficient in the boiler.

[0012] In a possible implementation, the determining the steam production of the boiler in the load variation period according to the heat transfer coefficient comprises:

[0013] The heat absorption of boiler water in the load variation period is calculated according to the heat transfer coefficient, and a ratio of the heat absorption to a specific enthalpy difference of water and saturated steam is taken as the steam production of the boiler in the load variation period, where the heat absorption is the denominator, and the specific enthalpy difference of water and saturated steam is the numerator.

[0014] In a possible implementation, the determining the consumed water amount caused by the boiler load variation based on the steam production, the feed water amount and a preset energy balance correction coefficient comprises:

[0015] An absolute value of a difference between the steam production and the feed water amount is calculated, and the consumed water amount is calculated based on the absolute value, a preset energy balance correction coefficient and a length of the load variation period.

[0016] In a possible implementation, the adjusting the current total steam production of the boiler according to the consumed water amount comprises:

[0017] A sum of the consumed water amount and the current total steam production is taken as the adjusted current total steam production.

[0018] In a possible implementation, the determining the current drum feed water amount of the boiler according to the adjusted current total steam production comprises:

[0019] The adjusted current total steam production is taken as the drum feed water amount, and a change average of a drum liquid level after water feeding according to the drum feed water amount is obtained.

[0020] The drum feed water amount is adjusted by feedback of the change average of the drum liquid level, and the current drum feed water amount is obtained.

[0021] In a possible implementation, the adjusting the drum feed water amount by feedback of the change average of the drum liquid level, and obtaining the current drum feed water amount, comprises:

[0022] A water level flow correction coefficient is determined according to the change average of the drum liquid level, and a water amount adjustment value corresponding to a change of the drum liquid level is calculated based on the water level flow correction coefficient.

[0023] A sum of the water amount adjustment value and the drum feed water amount is taken as the current drum feed water amount.

[0024] In a possible implementation, the method further comprises:

[0025] acquire a mass accumulation of the main steam flow, and calculate a current total steam production of the boiler based on the mass accumulation and a preset mass balance correction coefficient.

[0026] The second aspect of the present application provides a drum level control system suitable for peak shaving operation of a CFB boiler, which comprises:

[0027] a steam production calculation unit configured to determine a heat transfer coefficient in the boiler according to operating parameters of the boiler, and determine a steam production of the boiler during a load variation period according to the heat transfer coefficient;

[0028] a water amount calculation unit configured to acquire a feed water amount during the load variation period, and determine a consumed water amount caused by boiler load variation based on the steam production, the feed water amount and a preset energy balance correction coefficient;

[0029] a feed water amount determination unit configured to adjust a current total steam production of the boiler according to the consumed water amount, and determine a current drum feed water amount of the boiler according to the adjusted current total steam production;

[0030] a drum level control unit configured to control a drum level according to the current drum feed water amount.

[0031] The third aspect of the present application provides an electronic device, comprising at least one processor and a memory connected to the processor, wherein:

[0032] the memory is configured to store a computer program;

[0033] the processor is configured to execute the computer program, so that the electronic device can implement the drum level control method suitable for peak shaving operation of a CFB boiler according to the first aspect or any implementation manner of the first aspect.

[0034] The fourth aspect of the present application provides a computer program product comprising computer readable instructions, which, when executed on an electronic device, cause the electronic device to implement the drum level control method suitable for peak shaving operation of a CFB boiler according to the first aspect or any implementation manner of the first aspect.

[0035] By means of the technical scheme, the application provides a drum liquid level control method and related device suitable for CFB boiler peak shaving operation, the method calculates the heat transfer coefficient in the boiler according to the operation parameters of the boiler, determines the steam production of the boiler in the load change period according to the heat transfer coefficient, obtains the feed water in the load change period, determines the consumed water caused by the load change of the boiler based on the steam production, the feed water and a preset energy balance correction coefficient, adjusts the current total steam production of the boiler through the consumed water, thereby determining the current drum feed water of the boiler, and controls the drum liquid level according to the current drum feed water. When determining the current drum feed water, the method considers the consumed water caused by the load change of the boiler in the operation process of the boiler, obtains more accurate consumed water in the operation process of the boiler, thereby determining more accurate drum feed water, and thereby controls the drum liquid level, effectively reducing the control deviation of the drum liquid level. BRIEF DESCRIPTION OF DRAWINGS

[0036] The above and other features, advantages, and aspects of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the sizes of the components and elements are not necessarily drawn to scale.

[0037] Figure 1 A flowchart of a drum liquid level control method suitable for CFB boiler peak shaving operation provided by an embodiment of the application is shown in the figure.

[0038] Figure 2 A structural diagram of a drum liquid level control system suitable for CFB boiler peak shaving operation provided by an embodiment of the application is shown in the figure.

[0039] Figure 3 A hardware structure block diagram of an electronic device provided by an embodiment of the application is shown in the figure. DETAILED DESCRIPTION

[0040] The embodiments of the application are described below in conjunction with the drawings. The terms used in the embodiment part of the application are only used to explain the specific embodiments of the application, and are not intended to limit the application.

[0041] The embodiments of the application are described below in conjunction with the drawings. Those skilled in the art can know that, with the development of technology and the appearance of new scenarios, the technical solutions provided by the embodiments of the application are also applicable to similar technical problems.

[0042] The terms "comprise", "comprising", "have", "having", "include", "including", "contain", "containing", "provide", "providing", "offer", "offering", "carry", "carrying", "can", "can" and any variations thereof in the specification and in the claims shall not be construed as excluding any additional elements, process steps, or method steps. They are used to merely express the inclusion of certain elements, process steps, or method steps.

[0043] The current drum level control includes two control angles, one is to directly control the drum level, and the other is to control the drum feed water flow.

[0044] In the control angle of directly controlling the drum level, two ways can be included: the first way is to increase monitoring parameters such as drum pressure and furnace pressure on the basis of controlling the feed water flow, steam flow and drum level, and to correct the reverse control of the drum level according to the change of the monitoring parameters and through logical judgment. The second way is to construct a relationship formula of multiple parameters affecting the drum level through intelligent algorithm, and to determine the relationship formula for controlling the drum level through a large number of training. However, the above two control ways have poor control effect on the drum level when the boiler participates in peak regulation and rapidly changes load.

[0045] In the control angle of controlling the drum feed water flow, the feed water flow is mainly coarsely adjusted through the total steam production of the CFB boiler, and when the boiler participates in peak regulation and rapidly changes load, control deviation also easily exists.

[0046] In order to solve the above problems, the embodiment of the present application provides a drum level control method suitable for CFB boiler peak regulation operation. The drum level control method suitable for CFB boiler peak regulation operation of the embodiment of the present application will be described in detail below with reference to the accompanying drawings.

[0047] Reference Figure 1 , Figure 1 The flowchart of the drum level control method suitable for CFB boiler peak regulation operation provided by the embodiment of the present application is shown in FIG. 1. The drum level control method suitable for CFB boiler peak regulation operation provided by the embodiment of the present application can include steps S10 to S13, which will be described in detail below. Figure 1

[0048] S10, determining the heat transfer coefficient in the boiler according to the operating parameters of the boiler, and determining the steam production of the boiler in the load change period according to the heat transfer coefficient;

[0049] S11, obtaining the feed water flow in the load change period, and determining the consumed water flow caused by the load change of the boiler based on the steam production, the feed water flow and a preset energy balance correction coefficient;

[0050] S12, adjusting the current total steam production of the boiler according to the consumed water flow, and determining the current drum feed water flow of the boiler according to the adjusted current total steam production;​

[0051] S13, controlling the drum liquid level according to the current drum feedwater amount.

[0052] The boiler in the embodiment is a CFB boiler, which is a high-efficiency and clean boiler based on the CFB technology. The CFB (Circulating Fluidized Bed) refers to a technology for efficient combustion and pollution control based on the fluidization technology.

[0053] The load change period of the boiler can refer to the duration of the change of the load of the boiler due to the change of demand. The operating state of the boiler can mainly include a stable load state and a dynamic load change state, and the dynamic load change state can further include an ascending load state, a descending load state, and a sharp peak load fluctuation state. The load fluctuation in the load change period in the embodiment is obviously greater than the load fluctuation in the stable load state.

[0054] When the boiler is in the stable load state, the total steam production amount and the feedwater amount are in a mass balance relationship, and the feedwater amount can be directly determined according to the total steam production amount, so as to ensure the stability of the drum liquid level in the stable load state. Specifically, the embodiment can obtain the mass accumulation of the main steam (high-temperature and high-pressure steam for core work) flow. Since the main steam flow is often fluctuated when measured, the accumulated feedwater flow (feedwater flow of the economizer) can be used for correction to eliminate data errors. The current total steam production amount in the stable operation period of the boiler is calculated based on the mass accumulation and a preset mass balance correction coefficient, and the average value of the current total steam production amount in the stable operation period of the boiler is taken as the feedwater amount of the next period of the stable operation of the boiler. The feedwater amount calculation formula of the stable operation period of the boiler can be as follows:

[0055] ;

[0056] wherein, the feedwater amount of the next period of the stable operation of the boiler can be represented by the formula; the preset mass balance correction coefficient can be used for correcting the feedwater amount to ensure that it is within a reasonable range. The preset mass balance correction coefficient can be determined according to the past operation data, and can be updated and optimized through the accumulated operation data or operation state; the mass flow of the main steam flow can be represented by the formula, and the unit can be kg / s; The time length of the stable operation period of the boiler can be represented, and the time length of the stable operation of the boiler is related to the capacity and structural parameters of the boiler, such as two boilers with different capacities, a large-capacity boiler can be continuously operated, or a large-capacity boiler can be equipped with more components to maintain stable operation; The mass accumulation of the main steam flow in the stable operation period of the boiler can be represented, The total steam production in the stable operation period of the boiler can be represented, and the unit can be kg / s.

[0057] When the boiler is in a dynamic load change state, the mass balance relationship between the total steam production and the feed water amount is unbalanced, and controlling the feed water amount according to the total steam production is easy to produce control deviation. Therefore, the embodiment selects to control the feed water amount from the perspective of energy balance during load change, thereby controlling the steam drum level. Specifically, the embodiment calculates the steam production of the boiler in the load change period according to the heat absorption of the water circulation system, and obtains the feed water amount of the boiler in the load change period, calculates the consumed water amount caused by load change based on the absolute value of the difference between the steam production and the feed water amount, takes the sum of the consumed water amount and the current total steam production as the adjusted current total steam production, and controls the feed water amount according to the adjusted current total steam production, thereby ensuring the stability of the steam drum level in the dynamic load change state.

[0058] Specifically, first, the heat transfer coefficient of the boiler in the load change period is calculated according to the operating parameters of the boiler. The heat transfer coefficient in the boiler can refer to the heat transferred through the boiler heating surface (such as water wall, superheater, economizer, etc.) under the conditions of unit time, unit heat transfer area and unit temperature difference, which is a parameter for characterizing the heat transfer capacity of the boiler.

[0059] The operating parameters of the boiler can refer to parameters representing the combustion, fluidization, heat transfer and other states of the boiler. In the embodiment, the operating parameters of the boiler can specifically include: boiler fuel ash forming characteristic coefficient, boiler geometric characteristic coefficient, boiler operation fluidization velocity and boiler operation circulating ash concentration. Among them, the boiler fuel ash forming characteristic coefficient can refer to a parameter for measuring the ash generation and physical and chemical properties of the boiler after fuel combustion, which is a quantitative index of the operation of the boiler; the boiler geometric characteristic coefficient can refer to a parameter representing the geometric shape of the boiler (mainly the geometric shape of the structure participating in fluidization in the boiler); the boiler operation fluidization velocity can refer to the air cross-sectional velocity required for the bed material particles in the furnace to be blown up by the primary air (or fluidization air) and maintained in a stable circulating state; the boiler operation circulating ash concentration can refer to the mass fraction of solid particles (ash, desulfurization products, etc.) participating in circulation in unit volume of flue gas or circulating material in the boiler.

[0060] In the embodiment, the boiler fuel ash formation characteristic coefficient, the boiler geometric characteristic coefficient, the boiler operation fluidization velocity and the boiler operation circulating ash concentration can affect the heat transfer capacity in the boiler. Specifically, the boiler fuel ash formation characteristic coefficient can reflect the quality (such as granularity) of the heat transfer carrier (circulating ash) in the boiler; the boiler geometric characteristic coefficient can reflect the heat transfer environment in the boiler, such as heat transfer contact area, etc.; the boiler operation fluidization velocity can reflect whether the fluid is in uniform contact with the heating surface; and the boiler operation circulating ash concentration can reflect the concentration of the heat transfer carrier (circulating ash), which can directly affect the heat transfer capacity of the boiler, such as the greater the concentration, the more intense the collision heat exchange between the ash particles and the heat transfer surface, and the higher the heat transfer capacity.

[0061] Therefore, the embodiment selects to calculate the heat transfer coefficient in the boiler according to the boiler fuel ash formation characteristic coefficient, the boiler geometric characteristic coefficient, the boiler operation fluidization velocity and the boiler operation circulating ash concentration. Specifically, the embodiment takes the product of the boiler fuel ash formation characteristic coefficient, the boiler geometric characteristic coefficient, the boiler operation fluidization velocity and the boiler operation circulating ash concentration as the heat transfer coefficient in the boiler. The formula form can be as follows:

[0062] ;

[0063] wherein, may represent the heat transfer coefficient of the heating surface (mainly the water cooling wall), and the unit can be kw / (m 2 ×℃); may represent the boiler fuel ash formation characteristic coefficient; may represent the boiler geometric characteristic coefficient, and the unit can be (kw×s) / (m×kg×℃); may represent the boiler operation fluidization velocity, and the unit can be m / s; may represent the boiler operation circulating ash concentration, and the unit can be kg / m 3 .

[0064] Secondly, after obtaining the heat transfer coefficient of the boiler in the load change period in the embodiment, the total heat absorption amount of the water circulation system of the boiler in the load change period can be calculated according to the heat transfer coefficient. The embodiment first calculates the heat absorption amount in unit time, and then obtains the total heat absorption amount in the load change period through integral calculation or accumulation calculation. The calculation formula of the heat absorption amount in unit time can be as follows:

[0065] ;

[0066] wherein, may represent the heat absorption amount in unit time, and the unit can be kJ / s; may represent the heat transfer area of the heating surface, and the unit can be m 3 ; The heat transfer coefficient of the heat receiving surface can be represented by h. The heat exchange temperature difference can be represented by ΔT.

[0067] Secondly, since the heat absorption amount and the steam production amount of the water circulation system in the boiler are balanced in the time average, the embodiment can calculate the heat absorption amount of the boiler water in the load change period according to the heat transfer coefficient, and then take the ratio of the heat absorption amount and the specific enthalpy difference of the water and the saturated steam as the steam production amount of the boiler in the load change period, wherein the heat absorption amount is the denominator, and the specific enthalpy difference of the water and the saturated steam is the numerator. The calculation formula of the steam production amount can be as follows:

[0068] ;

[0069] Wherein, The steam production amount in the load change period can be represented by m, and the unit can be kg / s; The heat absorption amount can be represented by Q; The specific enthalpy of the saturated steam can be represented by h g, and the unit can be kJ / kg; The specific enthalpy of the feed water can be represented by h f, and the unit can be kJ / kg. Wherein, the specific enthalpy can refer to the total energy of unit mass of matter.

[0070] Finally, after obtaining the steam production amount in the load change period, the embodiment obtains the feed water amount of the boiler in the load change period, calculates the absolute value of the difference between the steam production amount and the feed water amount, calculates the consumed water amount (the value of the consumed water amount can be positive, negative or 0) based on the absolute value of the difference, a preset energy balance correction coefficient and the time length of the load change period, and takes the consumed water amount as the feed water amount of the next period of the boiler load change condition. The calculation formula of the feed water amount of the boiler load change condition can be as follows:

[0071] ;

[0072] Wherein, The feed water amount of the next period of the boiler load change condition can be represented by m f ; The preset energy balance correction coefficient can be represented by k, which is used to correct the consumed water amount to ensure that it is within a reasonable range. The preset energy balance correction coefficient can be determined according to the past operation data, and can be updated and optimized through the accumulated operation data or operation condition; The steam production amount in the load change period calculated according to the heat absorption amount can be represented by m; The feed water amount in the load change period can be represented by m f ; The time length of the load change period can be expressed in seconds, and the time length of the load change of the boiler is related to the boiler capacity and the safe operation water volume of the drum. For example, for two boilers with different capacities, to meet the same steam increase demand, the large-capacity boiler can produce more steam in the same time, and it is easier to meet the steam increase demand, and the time length of the load change is shorter.

[0073] When the load of the boiler changes, the water consumption is different from that when the boiler is in stable operation. Specifically, when the steam demand increases, the boiler is in the state of increasing load, the steam output increases, and the water consumption increases compared with that when the boiler is in stable operation; when the steam demand decreases, the boiler is in the state of decreasing load, the steam output decreases, and the water consumption decreases compared with that when the boiler is in stable operation. Therefore, when it is necessary to determine the feed water amount of the next period, the running data of the previous period can be used for determination.

[0074] When all the previous periods are stable operation periods, the total steam production amount of the previous periods can be calculated, and the average value of the total steam production amount in the stable operation periods of the boiler is taken as the feed water amount of the next period of the stable operation of the boiler according to the law of conservation of mass.

[0075] When the previous periods include stable operation periods and load change periods, the feed water amounts of the stable operation periods and the load change periods in the next period can be calculated respectively, and the sum of the feed water amounts of the two periods is taken as the feed water amount of the next period. Specifically, the total steam production amount of the stable operation periods is calculated, and the average value of the total steam production amount in the stable operation periods of the boiler is taken as the feed water amount of the next period of the stable operation of the boiler according to the law of conservation of mass; the steam production amount of the load change period is calculated according to the heat absorption amount, and the average water consumption of the load change period is calculated based on the absolute value of the difference between the steam production amount and the feed water amount, a preset energy balance correction coefficient and the time length of the load change period, which is taken as the feed water amount of the next period of the load change of the boiler. The sum of the feed water amount of the next period of the stable operation of the boiler and the feed water amount of the next period of the load change of the boiler is taken as the feed water amount of the next period.

[0076] The embodiment divides the operation stage of the boiler into a stable operation stage and a load change operation stage when controlling the drum level, and calculates the consumed water quantity in the stable operation and the consumed water quantity in the load change operation respectively, controls the feed water quantity based on the total of the consumed water quantities in the two stages, and realizes the control mode of coarse adjustment by mass balance and fine adjustment by energy balance. When the boiler is in load mutation, the embodiment can quickly calculate the additional consumed water quantity caused by load change according to energy balance, quickly adjusts the feed water quantity in load mutation in combination with the feed water quantity calculated by mass balance, and takes the total of the additional consumed water quantity calculated by energy balance and the feed water quantity calculated by mass balance as the current drum feed water quantity, and can directly control the drum level based on the current drum feed water quantity, which can effectively reduce the change range of the water level adjustment, make the fluctuation of the drum level smaller in the whole control process, and effectively ensure the stability of the drum level.

[0077] In order to further ensure the stability of the drum level, the embodiment also adds feedback adjustment of the drum level. Specifically, the embodiment takes the adjusted current total steam production as the drum feed water quantity, controls the feed water quantity, continuously obtains the average value of the change of the drum level in a period of time after the feed water is performed according to the drum feed water quantity, adjusts the drum feed water quantity through the average value of the change of the drum level, obtains the current drum feed water quantity, continues to control the feed water quantity according to the current drum feed water quantity, and thus controls the drum level. Of course, in another optional embodiment, the embodiment can realize the feedback adjustment of the drum level by using PID adjustment and other automatic adjustment modes.

[0078] Specifically, the embodiment can determine the water level flow correction coefficient according to the average value of the change of the drum level, calculate the water quantity adjustment value corresponding to the change of the drum level based on the water level flow correction coefficient, and take the sum of the water quantity adjustment value and the drum feed water quantity as the current drum feed water quantity. The calculation formula of the water quantity adjustment value can be as follows:

[0079] ;

[0080] Wherein, The water quantity adjustment value can be represented by; The water level flow correction coefficient has a quadratic function relationship with the drum level value, can be determined according to the past operation data, and can be updated and optimized through the operation situation; The conversion coefficient of the drum level and the feed water quantity can be represented by, and the unit can be kg / mm, which can be determined according to the operation data; The feed water quantity of the next period of stable operation of the boiler can be represented by; The feed water quantity of the maximum continuous operation load of the boiler can be represented by, and the unit can be kg / s; The detection value of the drum level of the boiler can be represented by, and the unit can be mm; The continuous reading duration of the drum liquid level can be expressed in s.

[0081] Since the current drum feedwater amount integrates the feedwater amount during the stable operation period, the feedwater amount during the load change period, and the water adjustment value of the drum liquid level feedback regulation, the control target value (current drum feedwater amount) of the boiler feedwater flow in the next period can be expressed as:

[0082]

[0083] Wherein, The control target value (current drum feedwater amount) can be expressed as: The feedwater amount during the stable operation of the boiler can be expressed as: The compensation feedwater amount during the load change of the boiler can be expressed as: The water adjustment value of the drum liquid level feedback regulation can be expressed as:

[0084] The control target value (current drum feedwater amount) is transmitted to the feedwater regulation system in this embodiment to regulate the current feedwater amount of the boiler, so as to control the drum liquid level of the boiler.

[0085] The present application provides a drum liquid level control method suitable for peak regulation operation of a CFB boiler. The method calculates the heat transfer coefficient in the boiler according to the operating parameters of the boiler, determines the steam production of the boiler during the load change period according to the heat transfer coefficient, obtains the feedwater amount during the load change period, determines the consumed water amount caused by the load change of the boiler based on the steam production, the feedwater amount, and a preset energy balance correction coefficient, adjusts the current total steam production of the boiler through the consumed water amount, thereby determining the current drum feedwater amount of the boiler, and controls the drum liquid level according to the current drum feedwater amount. In the method for determining the current drum feedwater amount, the consumed water amount caused by the load change of the boiler during the operation of the boiler is considered, a more accurate consumed water amount during the operation of the boiler is obtained, a more accurate drum feedwater amount is determined, and the drum liquid level control is performed, thereby effectively reducing the control deviation of the drum liquid level.

[0086] The above introduces a drum liquid level control method suitable for peak regulation operation of a CFB boiler provided by the embodiments of the present application. The system applying the above drum liquid level control method suitable for peak regulation operation of a CFB boiler will be introduced below.

[0087] Please refer to Figure 2 , Figure 2 The structure diagram of a drum liquid level control system suitable for peak regulation operation of a CFB boiler provided by the embodiments of the present application is shown in Figure 2 The drum liquid level control system suitable for peak regulation operation of a CFB boiler can include:

[0088] ​The steam production amount calculation unit 100 is configured to determine a heat transfer coefficient in the boiler according to the operating parameters of the boiler, and determine the steam production amount of the boiler in the load variation period according to the heat transfer coefficient.

[0089] The water amount calculation unit 110 is configured to obtain a feed water amount in the load variation period, and determine a consumed water amount caused by the boiler load variation based on the steam production amount, the feed water amount, and a preset energy balance correction coefficient.

[0090] The feed water amount determination unit 120 is configured to adjust the current total steam production amount of the boiler according to the consumed water amount, and determine a current drum feed water amount of the boiler according to the adjusted current total steam production amount.

[0091] The liquid level control unit 130 is configured to control the drum liquid level according to the current drum feed water amount.

[0092] In a possible implementation, the determination of the heat transfer coefficient in the boiler according to the operating parameters of the boiler in the steam production amount calculation unit 100 can be specifically configured as follows:

[0093] The product of the boiler fuel ash formation characteristic coefficient, the boiler geometric characteristic coefficient, the boiler operating fluidization velocity, and the boiler operating circulating ash concentration is taken as the heat transfer coefficient in the boiler.

[0094] In a possible implementation, the determination of the steam production amount of the boiler in the load variation period according to the heat transfer coefficient in the steam production amount calculation unit 100 can be specifically configured as follows:

[0095] The heat absorption amount of the boiler water in the load variation period is calculated according to the heat transfer coefficient, and the ratio of the heat absorption amount to the specific enthalpy difference between water and saturated steam is taken as the steam production amount of the boiler in the load variation period, where the heat absorption amount is the denominator, and the specific enthalpy difference between water and saturated steam is the numerator.

[0096] In a possible implementation, the water amount calculation unit 110 can be specifically configured as follows:

[0097] The absolute value of the difference between the steam production amount and the feed water amount is calculated, and the consumed water amount is calculated based on the absolute value of the difference, the preset energy balance correction coefficient, and the length of the load variation period.

[0098] In a possible implementation, the adjustment of the current total steam production amount of the boiler according to the consumed water amount in the feed water amount determination unit 120 can be specifically configured as follows:

[0099] The sum of the consumed water amount and the current total steam production amount is taken as the adjusted current total steam production amount.

[0100] In a possible implementation, the determination of the current drum feed water amount of the boiler according to the adjusted current total steam production amount in the feed water amount determination unit 120 can be specifically configured as follows:

[0101] The adjusted current total steam production is used as the steam drum feedwater rate. The average change in the steam drum liquid level after feeding water according to the steam drum feedwater rate is obtained. The steam drum feedwater rate is adjusted based on the average change in the steam drum liquid level to obtain the current steam drum feedwater rate.

[0102] In one possible implementation, the feedwater determination unit 120 adjusts the steam drum feedwater flow rate by feeding back the average change in the steam drum liquid level to obtain the current steam drum feedwater flow rate. This can be specifically configured as follows:

[0103] The water level and flow rate correction coefficient is determined based on the average change in the steam drum liquid level. The water volume adjustment value corresponding to the change in the steam drum liquid level is calculated based on the water level and flow rate correction coefficient. The sum of the water volume adjustment value and the steam drum feedwater is taken as the current steam drum feedwater.

[0104] In one possible implementation, a total steam production calculation unit is also included:

[0105] The total steam production calculation unit is used to obtain the mass accumulation of the main steam flow rate and calculate the current total steam production of the boiler based on the mass accumulation and the preset mass balance correction coefficient.

[0106] This application also provides an electronic device in its embodiments. (See reference...) Figure 3 The diagram illustrates a structural schematic suitable for implementing the electronic device in the embodiments of this application. The electronic device in the embodiments of this application may include, but is not limited to, fixed terminals such as mobile phones, laptops, PDAs (personal digital assistants), PADs (tablet computers), desktop computers, etc. Figure 3 The electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0107] like Figure 3 As shown, the electronic device may include a processing unit (e.g., a central processing unit, a graphics processing unit, etc.) 301, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 302 or a program loaded from a storage device 308 into a random access memory (RAM) 303. When the electronic device is powered on, the RAM 303 also stores various programs and data required for the operation of the electronic device. The processing unit 301, ROM 302, and RAM 303 are interconnected via a bus 304. An input / output interface (I / O interface) 305 is also connected to the bus 304.

[0108] In general, the following devices can be connected to the I / O interface 305: input devices 306 including, for example, a touch screen, a touch pad, a keyboard, a mouse, a camera, a microphone, an accelerometer, a gyroscope, and the like; output devices 307 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, and the like; storage devices 308 including, for example, a memory card, a hard disk, and the like; and communication devices 309. The communication devices 309 can allow the electronic device to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 3 An electronic device having various devices is illustrated, but it is understood that all of the illustrated devices are not required to be implemented or present. More or less devices can alternatively be implemented or present.

[0109] The embodiment of the present application further provides a computer program product comprising computer readable instructions, which, when executed on an electronic device, cause the electronic device to implement any of the steam drum level control methods for peak regulation operation of a CFB boiler provided by the embodiments of the present application.

[0110] The embodiment of the present application further provides a computer readable storage medium, which carries one or more computer programs, which, when executed by an electronic device, can cause the electronic device to implement any of the steam drum level control methods for peak regulation operation of a CFB boiler provided by the embodiments of the present application.

[0111] In addition, it should be noted that the system embodiments described above are merely illustrative, wherein the units described as separate components can or can not be physically separated, and the components displayed as units can or can not be physical units, i.e., they can be located in one place, or distributed on multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the embodiments. In addition, the connection relationship between the modules in the system embodiments provided by the present application indicates that there is a communication connection between them, which can be implemented as one or more communication buses or signal lines.

[0112] Those skilled in the art can clearly understand that the application can be implemented by means of software plus necessary universal hardware, and of course can also be implemented by means of dedicated hardware including special-purpose integrated circuits, special-purpose CPUs, special-purpose memories, special-purpose components, etc. Generally, any function completed by a computer program can be easily implemented by corresponding hardware, and the specific hardware structure for implementing the same function can also be various, such as analog circuits, digital circuits, or special-purpose circuits, etc. However, for the present application, software program implementation is a better embodiment. Based on such understanding, the technical solutions of the present application can be embodied in the form of a software product, which is stored in a readable storage medium, such as a floppy disk, a U disk, a mobile hard disk, a ROM, a RAM, a magnetic disk or an optical disk, etc., and includes a plurality of instructions for causing a computer device (which can be a personal computer, a training device, or a network device, etc.) to execute the methods described in the various embodiments of the present application.

[0113] In the above embodiments, all or part of the embodiments can be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments can be implemented in the form of a computer program product.

[0114] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another, for example, the computer instructions can be transmitted from one website, computer, training device or data center to another website, computer, training device or data center through wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) mode. The computer-readable storage medium can be any available medium that can be stored by a computer or a data storage device such as a training device, a data center, etc. integrated with one or more available media. The available media can be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (SSD)), etc.

[0115] Each of the embodiments in the specification is described in a relevant manner, and the same or similar parts between the embodiments can be referred to each other. Each of the embodiments focuses on the difference from other embodiments. In particular, for the device embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the part of the method embodiments.

[0116] It can be understood that, before using the technical solutions disclosed in the embodiments of the present disclosure, the type of personal information involved in the present disclosure, the use range, the use scenario, etc. should be informed to the user and the authorization of the user should be obtained through appropriate means according to relevant laws and regulations.

[0117] The above only describes the embodiments of the present application and is not intended to limit the present application. The present application can have various changes and modifications for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for controlling the level of a drum for a CFB boiler for peak shaving operation, characterized in that, The drum level control method suitable for peak shaving operation of the CFB boiler comprises: determining a heat transfer coefficient in the boiler according to operation parameters of the boiler, and determining steam production of the boiler in a load variation period according to the heat transfer coefficient; obtaining a feed water amount in the load variation period, and determining a consumed water amount caused by boiler load variation based on the steam production, the feed water amount and a preset energy balance correction coefficient; adjusting a current total steam production of the boiler according to the consumed water amount, and determining a current drum feed water amount of the boiler according to the adjusted current total steam production; controlling the drum level according to the current drum feed water amount.

2. The drum level control method for peak shaving operation of a CFB boiler as claimed in claim 1, wherein, The method comprises: taking a product of a boiler fuel ash formation characteristic coefficient, a boiler geometric characteristic coefficient, a boiler operation fluidization velocity and a boiler operation circulating ash concentration as the heat transfer coefficient in the boiler.

3. The drum level control method for peak shaving operation of a CFB boiler as claimed in claim 1, wherein, The method comprises: calculating a heat absorption amount of boiler water in the load variation period according to the heat transfer coefficient, and taking a ratio of the heat absorption amount to a specific enthalpy difference between water and saturated steam as the steam production of the boiler in the load variation period, wherein the heat absorption amount is a denominator, and the specific enthalpy difference between water and saturated steam is a numerator.

4. The drum level control method for peak shaving operation of a CFB boiler as claimed in claim 1, wherein, The method comprises: calculating an absolute value of a difference between the steam production and the feed water amount, and calculating the consumed water amount based on the absolute value, the preset energy balance correction coefficient and a time length of the load variation period.

5. The drum level control method for peak shaving operation of a CFB boiler as claimed in claim 1, wherein, The method comprises: taking a sum of the consumed water amount and the current total steam production as the adjusted current total steam production.

6. The drum level control method for peak shaving operation of a CFB boiler as claimed in claim 1 wherein, The method comprises: taking the adjusted current total steam production as the drum feed water amount, obtaining a change average of the drum level after water feeding according to the drum feed water amount, and adjusting the drum feed water amount through feedback of the change average of the drum level to obtain the current drum feed water amount. The method comprises:

7. The drum level control method for peak shaving operation of a CFB boiler as claimed in claim 6, wherein, determining a water level flow correction coefficient according to the change average of the drum level, calculating a water amount adjustment value corresponding to the change of the drum level based on the water level flow correction coefficient, and taking a sum of the water amount adjustment value and the drum feed water amount as the current drum feed water amount. The method further comprises: obtaining a mass accumulation of main steam flow, and calculating the current total steam production of the boiler based on the mass accumulation and a preset mass balance correction coefficient.

8. The drum level control method for peak shaving operation of a CFB boiler as claimed in claim 1, wherein, The drum level control system suitable for peak shaving operation of the CFB boiler comprises: a steam production calculation unit configured to determine a heat transfer coefficient in the boiler according to operation parameters of the boiler, and determine steam production of the boiler in a load variation period according to the heat transfer coefficient; 9. A drum level control system for peak shaving operation of a CFB boiler, characterized in that, ​ ​ The water amount calculation unit is configured to obtain a feed water amount in the load variation period, and determine a consumed water amount caused by the boiler load variation based on the steam production amount, the feed water amount, and a preset energy balance correction coefficient. The feed water amount determination unit is configured to adjust a current total steam production amount of the boiler according to the consumed water amount, and determine a current drum feed water amount of the boiler according to the adjusted current total steam production amount. The liquid level control unit is configured to control a drum liquid level according to the current drum feed water amount.

10. An electronic device, comprising: The electronic device comprises at least one processor and a memory connected with the processor, wherein: The memory is configured to store a computer program; The processor is configured to execute the computer program, so that the electronic device can implement the drum liquid level control method for the peak shaving operation of the CFB boiler as claimed in any one of claims 1 to 8.

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