Flow control method and device for heating unit heating steam regulating valve

Abstract

The application provides a flow control method and device for a heating unit heating steam regulating valve, and belongs to the field of heating. The method comprises the following steps: determining a first characteristic curve of a characteristic flow coefficient of a communication pipe heating regulating butterfly valve and an opening degree thereof; determining a second characteristic curve of a characteristic flow coefficient of a heating steam regulating valve and an opening degree thereof; determining an opening degree of the communication pipe heating regulating butterfly valve corresponding to a predetermined regulating amount of heating steam flow based on the first characteristic curve and a corrected characteristic flow coefficient of the communication pipe heating regulating butterfly valve; determining an opening degree of the heating steam regulating valve corresponding to the predetermined regulating amount of heating steam flow based on the second characteristic curve and a corrected characteristic flow coefficient of the heating steam regulating valve; and determining the opening degrees of the communication pipe heating regulating butterfly valve and the heating steam regulating valve respectively based on the opening degree of the communication pipe heating regulating butterfly valve corresponding to the predetermined regulating amount of heating steam flow, the opening degree of the heating steam regulating valve corresponding to the predetermined regulating amount of heating steam flow, and a preset opening degree range. The application can realize accurate control of the flow of the heating unit heating steam regulating valve.

Description

Technical Field

[0001] This invention relates to the field of heating technology, and in particular to a flow control method and device for a heating unit's steam supply regulating valve. Background Technology

[0002] With the large-scale integration of new energy sources into the grid, the peak-shaving support role of generator units within the grid has become increasingly prominent. In some regions, most generator units also undertake the task of external heating. When heating units simultaneously provide heating and power generation, if the frequency regulation parameters are not readjusted, the primary frequency regulation response performance of the turbine will deteriorate when the heating load on the unit is large.

[0003] Currently, the primary method to enhance the primary frequency regulation response capability of heating units is to utilize the thermal inertia of the heating network during operation and employ heating steam extraction regulating valves to participate in primary frequency regulation actions for a short period. Using this solution requires precise flow control of the heating unit's heating steam supply regulating valves.

[0004] However, current flow control systems for regulating valves are not integrated with the actual thermoelectric characteristics of the unit, leading to inaccurate flow control. How to accurately control the flow of the heating steam supply regulating valves of heating units based on the actual thermoelectric characteristics of the unit has become a pressing technical problem that needs to be solved. Summary of the Invention

[0005] This invention provides a flow control method and device for a heating steam supply regulating valve in a heating unit, in order to solve the problem of inaccurate flow control methods in current systems.

[0006] In a first aspect, embodiments of the present invention provide a flow control method for a heating steam supply regulating valve of a heating unit, comprising:

[0007] Determine the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve and its first characteristic curve of opening degree;

[0008] Determine the characteristic flow coefficient of the heating steam supply regulating valve and its second characteristic curve of its opening degree;

[0009] Based on the first characteristic curve and the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve after modification, the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of heating steam extraction flow is determined.

[0010] Based on the second characteristic curve and the modified flow coefficient of the heating steam supply regulating valve, the opening degree of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating steam extraction flow rate is determined.

[0011] Based on the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, the opening degree of the heating supply steam regulating valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, and the preset opening degree range, the opening degree of the connecting pipe heating regulating butterfly valve and the heating supply steam regulating valve are determined respectively.

[0012] In one possible implementation, determining the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve and its first characteristic curve relative to its opening degree includes:

[0013] Based on the design heat balance diagram provided by the turbine manufacturer, the corresponding data of low-pressure cylinder inlet steam flow rate and low-pressure cylinder inlet steam pressure under multiple design conditions are summarized, and the first fitting function of low-pressure cylinder inlet steam flow rate and low-pressure cylinder inlet steam pressure is obtained by fitting.

[0014] Based on the first fitting function and the low-pressure cylinder inlet pressure under different heating steam supply flow conditions, the low-pressure cylinder inlet flow rate under different heating steam supply flow conditions is calculated.

[0015] Based on the low-pressure cylinder inlet steam flow rate under different heating steam supply flow conditions, the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve is determined.

[0016] Based on the characteristic flow coefficient and opening data of the connecting pipe heating regulating butterfly valve under multiple heating and steam supply flow conditions, the first characteristic curve is obtained by fitting.

[0017] In one possible implementation, the characteristic flow coefficient F of the connecting pipe heating regulating butterfly valve IPLPCV(i) The formula for determining it is:

[0018] When p LPin(i) ≥Kcr×p IPexh(i) hour,

[0019]

[0020] When p LPin(i) <Kcr×p IPexh(i) hour,

[0021] F IPLPCV(i) =F LP(i) ;

[0022] Among them, F LP(i) p is the steam inlet flow rate of the low-pressure cylinder for the i-th heating steam supply. IPexh(i) p is the exhaust pressure of the intermediate-pressure cylinder for the i-th heating steam supply. LPin(i) Kcr is the inlet steam pressure of the low-pressure cylinder for the i-th heating steam supply, and Kcr is the critical pressure ratio of superheated steam.

[0023] In one possible implementation, determining the characteristic flow coefficient of the heating steam supply regulating valve and its second characteristic curve relative to its opening degree includes:

[0024] Based on the outlet water temperature of the heating network heater under different heating steam supply flow conditions, the inlet steam pressure of the heating network heater under different heating steam supply flow conditions is calculated.

[0025] Based on the inlet steam pressure of the heating network heater under different heating steam supply flow conditions, the characteristic flow coefficient of the heating steam supply regulating valve is determined.

[0026] Based on the flow coefficient and opening data of the heating and steam supply regulating valve under multiple heating and steam supply flow conditions, a second characteristic curve is obtained by fitting.

[0027] In one possible implementation, the characteristic flow coefficient F of the heating steam supply regulating valve is... CNCV(i) for:

[0028] When p DHin(i) ≥Kcr×p IPexh(i) hour,

[0029]

[0030] When p DHin(i) <Kcr×p IPexh(i) hour,

[0031] F CNCV(i) =F CN(i) ;

[0032] Among them, F CN(i) Let p be the heating steam supply flow rate for the i-th heating steam supply unit. IPexh(i) p is the exhaust pressure of the intermediate-pressure cylinder for the i-th heating steam supply. DHin(i) Let Kcr be the inlet steam pressure of the heater in the i-th heating network, and Kcr be the critical pressure ratio of superheated steam.

[0033] In one possible implementation, based on the first characteristic curve and the modified characteristic flow coefficient of the connecting pipe heating regulating butterfly valve, the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating steam extraction flow is determined, including:

[0034] Calculate the corresponding low-pressure cylinder inlet steam flow rate based on the low-pressure cylinder inlet steam pressure under normal heating operation conditions of the target heating unit.

[0035] Calculate the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve after the heating extraction steam flow rate is adjusted, and the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve is corrected to the test state.

[0036] Based on the first characteristic curve and the flow coefficient of the connecting pipe heating regulating butterfly valve corrected to the test state, the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating steam extraction flow is determined.

[0037] In one possible implementation, the characteristic flow coefficient F of the connecting pipe heating regulating butterfly valve after the heating extraction steam flow rate is adjusted. IPLPCVnew The formula for determining ′ is:

[0038] When p′ LPinnew ≥Kcr×p IPexh 'hour,

[0039]

[0040] When p′ LPinnew <Kcr×p IPexh 'hour,

[0041] F IPLPCVnew ′=F LP ′;

[0042] Corrected flow coefficient F of the connecting pipe heating regulating butterfly valve under test conditions IPLPCVCor 'for:

[0043]

[0044] Where, p′ LPinnew The low-pressure cylinder inlet pressure is the steam pressure after the heating extraction steam flow rate is adjusted; Kcr is the critical pressure ratio of superheated steam; p IPexh ′ represents the exhaust pressure of the intermediate-pressure cylinder during normal heating operation, F LP ′ represents the low-pressure cylinder inlet steam flow rate during normal heating operation, p ipex-set These are the set values ​​for all test conditions.

[0045] In one possible implementation, based on the second characteristic curve and the modified flow coefficient of the heating steam supply regulating valve, the opening degree of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating extraction steam flow is determined, including:

[0046] The new heating network heater outlet temperature is determined based on the heating network circulating water volume and heating steam extraction flow rate adjustment under normal heating operation conditions of the target heating unit.

[0047] Based on the new heating network heater outlet temperature, the characteristic flow coefficient of the heating steam supply regulating valve after the heating extraction steam flow rate is determined, as well as the characteristic flow coefficient of the heating steam supply regulating valve corrected to the test state.

[0048] Based on the second characteristic curve and the modified flow coefficient of the heating steam supply regulating valve, the opening degree of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating steam extraction flow rate is determined.

[0049] In one possible implementation, the characteristic flow coefficient F of the heating steam supply regulating valve after the heating extraction steam flow rate is adjusted. CNCVnew The formula for determining ′ is:

[0050] When p DHinnew ′≥Kcr×p IPexh 'hour,

[0051]

[0052] When p DHinnew ′ <Kcr×p IPexh 'hour,

[0053] F CNCVnew ′=F CNnew ′;

[0054] Corrected flow coefficient F of heating steam supply regulating valve under test conditions CNCVCor The formula for determining ′ is:

[0055]

[0056] Where, p DHinnew ′ represents the inlet steam pressure of the heating network heater after the heating extraction steam flow rate is adjusted, Kcr represents the critical pressure ratio of superheated steam, and p IPexh ′ represents the exhaust pressure of the intermediate-pressure cylinder during normal heating operation, F CNnew ′ represents the heating steam supply flow rate after adjustment of the heating extraction steam flow rate, p ipex-set These are the set values ​​for all test conditions.

[0057] Secondly, embodiments of the present invention provide a flow control device for a heating steam supply regulating valve of a heating unit, comprising:

[0058] The first curve determination module is used to determine the first characteristic curve of the characteristic flow coefficient and the opening degree of the connecting pipe heating regulating butterfly valve.

[0059] The second curve determination module is used to determine the second characteristic curve of the characteristic flow coefficient and the opening degree of the heating steam supply regulating valve.

[0060] The first opening determination module is used to determine the opening of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating steam extraction flow rate based on the first characteristic curve and the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve after modification.

[0061] The second opening determination module is used to determine the opening of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating steam extraction flow rate based on the second characteristic curve and the modified flow coefficient of the heating steam supply regulating valve.

[0062] The final value determination module is used to determine the opening of the connecting pipe heating regulating butterfly valve and the heating steam supply regulating valve based on the opening of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, the opening of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, and the preset opening range.

[0063] This invention provides a flow control method and apparatus for a heating steam supply regulating valve in a heating unit. By determining a first characteristic curve showing the characteristic flow coefficient and opening degree of the connecting pipe heating regulating butterfly valve, and a second characteristic curve showing the characteristic flow coefficient and opening degree of the heating steam supply regulating valve, the opening degree of the connecting pipe heating regulating butterfly valve corresponding to a predetermined adjustment amount of heating steam extraction flow can be obtained based on the first characteristic curve and the corrected characteristic flow coefficient of the connecting pipe heating regulating butterfly valve. Similarly, the opening degree of the heating steam supply regulating valve corresponding to a predetermined adjustment amount of heating steam extraction flow can be obtained based on the second characteristic curve and the corrected characteristic flow coefficient of the heating steam supply regulating valve. Finally, based on the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of heating steam extraction flow, the opening degree of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of heating steam extraction flow, and the preset opening degree range, the opening degrees of the connecting pipe heating regulating butterfly valve and the heating steam supply regulating valve can be determined respectively. This invention, based on the inherent thermoelectric characteristics of heating units and combined with the characteristics of various heating control valves, achieves precise control of the flow rate of the heating steam supply control valves of heating units. Furthermore, it can be used to enhance the primary frequency regulation response capability of the steam turbine of heating units or improve the response capability of the automatic power generation control of heating units. Attached Figure Description

[0064] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0065] Figure 1 This is a flowchart illustrating the implementation of the flow control method for the heating steam supply regulating valve of the heating unit provided in this embodiment of the invention.

[0066] Figure 2 This is a structural flowchart of the flow control method for the heating steam supply regulating valve of the heating unit provided in the embodiment of the present invention;

[0067] Figure 3 This is a schematic diagram of the flow control device for the heating steam supply regulating valve of the heating unit provided in an embodiment of the present invention. Detailed Implementation

[0068] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0069] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments will be described below in conjunction with the accompanying drawings.

[0070] Figure 1 and 2 The implementation flowchart of the flow control method for the heating steam supply regulating valve of the heating unit provided in the embodiment of the present invention is described in detail below:

[0071] S110. Determine the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve and its first characteristic curve of opening degree.

[0072] To accurately control the flow rate of the heating steam supply regulating valves in the heating unit, it is necessary to first conduct flow rate tests on the heating regulating butterfly valve and the heating steam supply regulating valve of the heating unit's condensing heating system. Specifically, this includes:

[0073] (1) Basic operating mode of the unit.

[0074] (2) Heating unit extraction and condensation heating method, steam turbine 80% rated steam inlet flow condition.

[0075] (3) During the test, the intermediate discharge pressure was kept stable at the set value P. ipex-set .

[0076] (4) The adjustment range of the heating extraction steam flow rate is from the rated heating extraction steam flow rate to zero, with a reduction of 50t / h each time. After each adjustment, the operating parameters are recorded after the heating extraction steam flow rate, the water level of the heating network heater, the intermediate discharge pressure, and the unit's electrical output have stabilized.

[0077] (5) Record the operating parameters including: unit power output, intermediate discharge pressure, heating steam extraction flow rate, low-pressure cylinder inlet steam pressure, connecting pipe heating regulating butterfly valve opening, heating steam supply regulating valve opening, and heating network heater outlet water temperature.

[0078] After obtaining the basic data through the above experiments, corresponding controls can be implemented.

[0079] In some embodiments, the process for determining the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve and its first characteristic curve of opening degree is as follows:

[0080] First, based on the design heat balance diagram provided by the turbine manufacturer, the corresponding data of low-pressure cylinder inlet steam flow rate and low-pressure cylinder inlet steam pressure under multiple design conditions are summarized, and the first fitting function of low-pressure cylinder inlet steam flow rate and low-pressure cylinder inlet steam pressure is obtained by fitting.

[0081] Next, based on the first fitting function and the low-pressure cylinder inlet pressure under different heating steam supply flow conditions, the low-pressure cylinder inlet flow rate under different heating steam supply flow conditions is calculated.

[0082] Then, based on the low-pressure cylinder inlet steam flow rate under different heating steam supply flow conditions, the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve is determined.

[0083] Finally, based on the characteristic flow coefficient and opening data of the connecting pipe heating regulating butterfly valve under multiple heating and steam supply flow conditions, the first characteristic curve was obtained by fitting.

[0084] In this embodiment, the first fitting function obtained for the low-pressure cylinder inlet steam flow rate and the low-pressure cylinder inlet steam pressure is F. LP =f1(p LPin ), where f1() is the fitting function.

[0085] In this embodiment, the characteristic flow coefficient F of the connecting pipe heating regulating butterfly valve IPLPCV(i) The formula for determining it is:

[0086] When p LPin(i) ≥Kcr×p IPexh(i) hour,

[0087]

[0088] When p LPin(i) <Kcr×p IPexh(i) hour,

[0089] F IPLPCV(i) =F LP(i) ;

[0090] Among them, F LP(i) p is the steam inlet flow rate of the low-pressure cylinder for the i-th heating steam supply. IPexh(i) p is the exhaust pressure of the intermediate-pressure cylinder for the i-th heating steam supply. LPin(i) Kcr is the inlet steam pressure of the low-pressure cylinder for the i-th heating steam supply, and Kcr is the critical pressure ratio of superheated steam.

[0091] In this embodiment, the characteristic flow coefficient F of the connecting pipe heating regulating butterfly valve under multiple heating steam supply flow conditions is used. IPLPCV Opening data VO of the regulating butterfly valve for heating connected to the pipe IPLPCV The first characteristic curve F is obtained by fitting. IPLPCV =f2(VO IPLPCV), where f2() is the fitting function.

[0092] S120. Determine the characteristic flow coefficient of the heating steam supply regulating valve and its second characteristic curve of opening degree.

[0093] In some embodiments, the inlet steam pressure of the heating network heater can be calculated first based on the outlet water temperature of the heating network heater under different heating steam supply flow conditions.

[0094] Next, based on the inlet steam pressure of the heating network heater under different heating steam supply flow conditions, the characteristic flow coefficient of the heating steam supply regulating valve is determined.

[0095] Finally, based on the flow coefficient and opening data of the heating and steam supply regulating valve under multiple heating and steam supply flow conditions, a second characteristic curve was obtained by fitting.

[0096] In this embodiment, the inlet steam pressure p of the heating network heater under different heating steam supply flow conditions DHin(i) p DHin(i) =f3(t) DHWo(i) +TTD DH );

[0097] Where, p DHin The inlet steam pressure of the heating network heater is t. DHWo Here, f is the outlet water temperature of the heating network heater, and f3() is the steam-water characteristic function calculated by the International Federation for Water and Steam Characteristics based on temperature to determine the saturation pressure. (TD) DH This is the design end difference of the heating network heater.

[0098] In this embodiment, the characteristic flow coefficient F of the heating steam supply regulating valve under any heating steam supply flow condition is... CNCV(i) for:

[0099] When p DHin(i) ≥Kcr×p IPexh(i) hour,

[0100]

[0101] When p DHin(i) <Kcr×p IPexh(i) hour,

[0102] F CNCV(i) =F CN(i) ;

[0103] Among them, F CN(i) Let p be the heating steam supply flow rate for the i-th heating steam supply unit. IPexh(i) p is the exhaust pressure of the intermediate-pressure cylinder for the i-th heating steam supply. DHin(i) Let Kcr be the inlet steam pressure of the heater in the i-th heating network, and Kcr be the critical pressure ratio of superheated steam.

[0104] In this embodiment, the characteristic flow coefficient and opening data of the heating and steam supply regulating valve under multiple heating and steam supply flow conditions are summarized, and the characteristic flow coefficient F of the heating and steam supply regulating valve is fitted. CNCV With heating steam supply regulating valve opening VO CNCV The second characteristic curve F CNCV =f4(VO CNCV ), where f4() is the fitting function.

[0105] S130. Based on the first characteristic curve and the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve after modification, determine the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating steam extraction flow.

[0106] In some embodiments, the corresponding low-pressure cylinder inlet steam flow rate can be calculated first based on the low-pressure cylinder inlet steam pressure under normal heating operation conditions of the target heating unit.

[0107] Then, calculate the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve after adjusting the heating extraction steam flow rate, and the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve corrected to the test state.

[0108] Finally, based on the first characteristic curve and the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve corrected to the test state, the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating steam extraction flow is determined.

[0109] In this embodiment, firstly, based on the low-pressure cylinder inlet steam pressure p′ under the current normal heating operation conditions of the heating unit... LPin Calculate the corresponding low-pressure cylinder inlet steam flow rate F′ LP .

[0110] Then, after the predetermined adjustment amount △F of the heating extraction steam flow is achieved, the change in the low-pressure cylinder inlet steam flow is F′. LPnew =F′ LP -ΔF corresponds to the change in low-pressure cylinder inlet pressure p′ LPinnew .

[0111] Next, the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve is calculated after the heating steam extraction flow rate is adjusted.

[0112] When p′ LPinnew ≥Kcr×p IPexh 'hour,

[0113]

[0114] When p ′I ′LPinnew <Kcr×p IPexh At ′, FIPLPCVnew ′=F LP ′;

[0115] Where, p I LPinnew The low-pressure cylinder inlet pressure is the steam pressure after the heating extraction steam flow rate is adjusted; Kcr is the critical pressure ratio of superheated steam; p IPexh ′ represents the exhaust pressure of the intermediate-pressure cylinder during normal heating operation, F LP The superscript ' represents the low-pressure cylinder inlet steam flow rate during normal heating operation. The superscript ' represents the data under normal heating operation conditions, and the subscript with "new" represents the corresponding data after the heating extraction steam flow rate has been adjusted.

[0116] Next, the characteristic flow coefficient F of the connecting pipe heating regulating butterfly valve, corrected to the test condition, is calculated. IPLPCVCor ′,

[0117]

[0118] Where, p ipex-set These are the set values ​​for all test conditions.

[0119] Finally, according to the characteristic flow coefficient F of the connecting pipe heating regulating butterfly valve IPLPCV Adjusting the opening degree of the butterfly valve VO connected to the heating pipe IPLPCV First characteristic curve F IPLPCV =f2(VO IPLPCV ), calculate the corrected characteristic flow coefficient F of the connecting pipe heating regulating butterfly valve. IPLPCVCor The corresponding opening degree VO of the connecting pipe heating regulating butterfly valve IPLPCVnew ′.

[0120] S140. Based on the second characteristic curve and the modified characteristic flow coefficient of the heating steam supply regulating valve, determine the opening degree of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating extraction steam flow.

[0121] In some embodiments, the new heating network heater outlet temperature can be determined first based on the heating network circulating water volume and heating extraction steam flow rate adjustment under normal heating operation conditions of the target heating unit.

[0122] Then, based on the new heating network heater outlet temperature, the characteristic flow coefficient of the heating steam supply regulating valve after the heating extraction steam flow rate is determined, as well as the characteristic flow coefficient of the heating steam supply regulating valve corrected to the test state.

[0123] Finally, based on the second characteristic curve and the modified flow coefficient of the heating steam supply regulating valve, the opening degree of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating extraction steam flow is determined.

[0124] In this embodiment, firstly, based on the current heating unit's normal heating operation condition, the circulating water volume F′ of the heating network is... DHW And the predetermined adjustment amount ΔF of the heating extraction steam flow rate, calculate the new heating network heater outlet temperature t′. DHWonew :

[0125]

[0126] Wherein, ΔHcon is the condensation enthalpy of the steam extracted for heating, which can be taken as the design value; C W This is the specific heat of water.

[0127] Then, the new inlet steam pressure p of the heating network heater after increasing the heating extraction steam flow rate adjustment was calculated. DHinnew ′, p DHinnew ′=f3(t′ DHWonew +TTD DH ).

[0128] Next, the characteristic flow coefficient of the heating steam supply regulating valve is calculated after the heating steam extraction flow rate is adjusted.

[0129] When p DHinnew ′≥Kcr×p IPexh 'hour,

[0130]

[0131] When p DHinnew ′ <Kcr×p IPexh At ′, F CNCVnew ′=F CNnew ′;

[0132] In the formula, the superscript ' represents the data under normal heating operation, and the subscript with "new" represents the corresponding data after the heating steam extraction flow rate is adjusted. DHinnew ′ represents the inlet steam pressure of the heating network heater after the heating extraction steam flow rate is adjusted, Kcr represents the critical pressure ratio of superheated steam, and p IPexh ′ represents the exhaust pressure of the intermediate-pressure cylinder during normal heating operation, F CNnew ′ represents the heating steam supply flow rate after adjustment of the heating extraction steam flow rate, p ipex-set These are the set values ​​for all test conditions.

[0133] Finally, according to the characteristic flow coefficient F of the heating and steam supply regulating valve CNCV With heating steam supply regulating valve opening VO CNCV Second characteristic curve FC NCV =f4(VO CNCV ), calculate the corrected characteristic flow coefficient FC of the heating steam supply regulating valve. NCVCor The corresponding opening degree VO of the heating steam supply regulating valve. CNCVnew ′.

[0134] S150. Based on the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, the opening degree of the heating supply steam regulating valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, and the preset opening degree range, the opening degree of the connecting pipe heating regulating butterfly valve and the heating supply steam regulating valve are determined respectively.

[0135] In some embodiments, the upper and lower limits of the opening of the connecting pipe heating regulating butterfly valve and the heating steam supply regulating valve are respectively:

[0136] VO CNCVmin ≤VO CNCV ≤VO CNCVmax ;

[0137] VO IPLPCVmin ≤VO IPLPCV ≤VO IPLPCvmax ;

[0138] For the regulating butterfly valve of the connecting pipe heating system, the final opening degree shall be determined according to the following principles:

[0139] When VO IPLPCVmin ≤VO IPLPCVnew ′≤VO IPLPCVmax At that time, the final opening degree is VO IPLPCVnew ′;

[0140] When VO IPLPCVmax <VO IPLPCVnew The final opening is VO. IPLPCVmax ;

[0141] When VO IPLPCVmin >VO IPLPCVnew The final opening is VO. IPLPCVmin ;

[0142] For heating steam supply regulating valves, the final opening degree shall be determined according to the following principles:

[0143] When VO CNCVmin ≤VO CNCVnew ′≤VO CNCVmax At that time, the final opening degree is VO CNCVnew ′;

[0144] When VO CNCVmax <VO CNCVnew The final opening is VO. CNCVmax ;

[0145] When VO CNCVmin >VO CNCVnew The final opening is VO. CNCVmin .

[0146] This invention, based on the inherent thermoelectric characteristics of heating units and the characteristics of various heating control valves, calculates the final opening degree of all heating extraction steam control valves after adjusting the heating extraction steam flow rate. It can be applied to enhance the primary frequency regulation response capability of heating unit turbines or improve the AGC response capability of heating units, effectively improving the grid connection performance of heating units.

[0147] The flow control method provided by this invention determines a first characteristic curve showing the characteristic flow coefficient and opening degree of the connecting pipe heating regulating butterfly valve and a second characteristic curve showing the characteristic flow coefficient and opening degree of the heating steam supply regulating valve. Based on these curves, the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating extraction steam flow can be obtained based on the first characteristic curve and the corrected characteristic flow coefficient of the connecting pipe heating regulating butterfly valve. Similarly, the opening degree of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating extraction steam flow can be obtained based on the second characteristic curve and the corrected characteristic flow coefficient of the heating steam supply regulating valve. Finally, based on the opening degrees of the connecting pipe heating regulating butterfly valve and the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, and the preset opening range, the opening degrees of the connecting pipe heating regulating butterfly valve and the heating steam supply regulating valve can be determined respectively. This invention, based on the inherent thermoelectric characteristics of the heating unit and combined with the characteristics of each heating regulating valve, achieves precise control of the flow rate of the heating steam supply regulating valve of the heating unit. It can also be used to enhance the primary frequency regulation response capability of the steam turbine of the heating unit or improve the response capability of the automatic power generation control of the heating unit.

[0148] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0149] The following are device embodiments of the present invention. For details not described in detail, please refer to the corresponding method embodiments described above.

[0150] Figure 3 A schematic diagram of the flow control device for the heating steam supply regulating valve of a heating unit provided in an embodiment of the present invention is shown. For ease of explanation, only the parts related to the embodiment of the present invention are shown, and are described in detail below:

[0151] like Figure 3 As shown, the flow control device 300 for the heating steam supply regulating valve of the heating unit includes:

[0152] The first curve determination module 310 is used to determine the first characteristic curve of the characteristic flow coefficient and the opening degree of the connecting pipe heating regulating butterfly valve.

[0153] The second curve determination module 320 is used to determine the second characteristic curve of the characteristic flow coefficient and the opening degree of the heating steam supply regulating valve.

[0154] The first opening degree determination module 330 is configured to determine the opening degree of the connecting pipe heat supply regulating butterfly valve corresponding to a predetermined regulation amount of the heating extraction steam flow based on the first characteristic curve and the corrected characteristic flow coefficient of the connecting pipe heat supply regulating butterfly valve.

[0155] The second opening degree determination module 340 is configured to determine the opening degree of the heating steam supply regulating valve corresponding to a predetermined regulation amount of the heating extraction steam flow based on the second characteristic curve and the corrected characteristic flow coefficient of the heating steam supply regulating valve.

[0156] The final value determination module 350 is configured to determine the opening degrees of the connecting pipe heat supply regulating butterfly valve and the heating steam supply regulating valve respectively based on the opening degree of the connecting pipe heat supply regulating butterfly valve corresponding to a predetermined regulation amount of the heating extraction steam flow, the opening degree of the heating steam supply regulating valve corresponding to a predetermined regulation amount of the heating extraction steam flow, and the preset range of the opening degree.

[0157] In a possible implementation manner, the first curve determination module 310 is configured to summarize the corresponding data of the low-pressure cylinder inlet steam flow and the low-pressure cylinder inlet steam pressure under multiple design conditions based on the design heat balance diagram provided by the steam turbine manufacturer, and fit to obtain the first fitting function of the low-pressure cylinder inlet steam flow and the low-pressure cylinder inlet steam pressure.

[0158] Based on the first fitting function and the low-pressure cylinder inlet steam pressure under different heating steam supply flow conditions, calculate the low-pressure cylinder inlet steam flow under different heating steam supply flow conditions.

[0159] Based on the low-pressure cylinder inlet steam flow under different heating steam supply flow conditions, determine the characteristic flow coefficient of the connecting pipe heat supply regulating butterfly valve.

[0160] Based on the characteristic flow coefficient of the connecting pipe heat supply regulating butterfly valve and the opening degree data of the connecting pipe heat supply regulating butterfly valve under multiple heating steam supply flow conditions, fit to obtain the first characteristic curve.

[0161] In a possible implementation manner, the determination formula for the characteristic flow coefficient FIPLPCV(i) of the connecting pipe heat supply regulating butterfly valve is:

[0162] When pLPin(i) ≥ Kcr × pIPexh(i),

[0163]

[0164] When pLPin(i) < Kcr × pIPexh(i),

[0165] FIPLPCV(i) = FLP(i);

[0166] Among them, FLP(i) is the low-pressure cylinder inlet steam flow rate of the i-th heating steam supply, and pIPexh(i) is the exhaust steam pressure of the intermediate-pressure cylinder of the i-th heating steam supply. pLPin(i) is the inlet steam pressure of the low-pressure cylinder of the i-th heating steam supply, and Kcr is the critical pressure ratio of superheated steam.

[0167] In a possible implementation, the second curve determination module 320 is configured to calculate the inlet steam pressure of the heat network heater under different heating steam supply flow conditions based on the outlet water temperature of the heat network heater under different heating steam supply flow conditions;

[0168] Determine the flow coefficient of the characteristic flow path of the heating steam supply regulating valve based on the inlet steam pressure of the heat network heater under different heating steam supply flow conditions;

[0169] Based on the flow coefficient of the characteristic flow path of the heating steam supply regulating valve and the opening data of the heating steam supply regulating valve under multiple heating steam supply flow conditions, a second characteristic curve is obtained by fitting.

[0170] In a possible implementation, the flow coefficient of the characteristic flow path of the heating steam supply regulating valve FCNCV(i) is:

[0171] When pDHin(i) ≥ Kcr × pIPexh(i),

[0172]

[0173] When pDHin(i) < Kcr × pIPexh(i),

[0174] FCNCV(i) = FCN(i);

[0175] Among them, FCN(i) is the heating steam supply flow rate of the i-th heating steam supply, pIPexh(i) is the exhaust steam pressure of the intermediate-pressure cylinder of the i-th heating steam supply, and p DHin(i) is the inlet steam pressure of the heat network heater of the i-th heating steam supply, and Kcr is the critical pressure ratio of superheated steam.

[0176] In a possible implementation, the first opening determination module 330 is configured to calculate the corresponding low-pressure cylinder inlet steam flow rate based on the low-pressure cylinder inlet steam pressure under the normal heating operation condition of the target heat supply unit;

[0177] Calculate the flow coefficient of the characteristic flow path of the connecting pipe heating regulating butterfly valve corresponding to the adjusted heating extraction steam flow rate, and the flow coefficient of the characteristic flow path of the connecting pipe heating regulating butterfly valve corrected to the test state;

[0178] Based on the first characteristic curve and the flow coefficient of the characteristic flow path of the connecting pipe heating regulating butterfly valve corrected to the test state, determine the opening of the connecting pipe heating regulating butterfly valve corresponding to achieving the predetermined adjustment amount of the heating extraction steam flow rate.

[0179] In one possible implementation, the characteristic flow coefficient F of the connecting pipe heating regulating butterfly valve after the heating extraction steam flow rate is adjusted. IPLPCVnew The formula for determining ′ is:

[0180] When p′L Pinnew ≥Kcr×p IPexh 'hour,

[0181]

[0182] When p′L Pinnew <Kcr×p IPexh 'hour,

[0183] F IPLPCVnew ′=F LP ′;

[0184] Corrected flow coefficient F of the connecting pipe heating regulating butterfly valve under test conditions IPLPCVCor 'for:

[0185]

[0186] Among them, p′L Pinnew The low-pressure cylinder inlet pressure is the steam pressure after the heating extraction steam flow rate is adjusted; Kcr is the critical pressure ratio of superheated steam; p IPexh ′ represents the exhaust pressure of the intermediate-pressure cylinder during normal heating operation, F LP ′ represents the low-pressure cylinder inlet steam flow rate during normal heating operation, p ipex-set These are the set values ​​for all test conditions.

[0187] In one possible implementation, the second opening determination module 340 is used to determine the new heating network heater outlet temperature based on the heating network circulating water volume and heating extraction steam flow rate adjustment under the normal heating operation conditions of the target heating unit.

[0188] Based on the new heating network heater outlet temperature, the characteristic flow coefficient of the heating steam supply regulating valve after the heating extraction steam flow rate is determined, as well as the characteristic flow coefficient of the heating steam supply regulating valve corrected to the test state.

[0189] Based on the second characteristic curve and the modified flow coefficient of the heating steam supply regulating valve, the opening degree of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating steam extraction flow rate is determined.

[0190] In one possible implementation, the characteristic flow coefficient F of the heating steam supply regulating valve after the heating extraction steam flow rate is adjusted. CNCVnew The formula for determining ′ is:

[0191] When p DHinnew ′≥Kcr×p IPexh 'hour,

[0192]

[0193] When p DHinnew ′<Kcr×p IPexh 'hour,

[0194] F CNCVnew ′=F CNnew ′;

[0195] Corrected flow coefficient F of heating steam supply regulating valve under test conditions CNCVCor The formula for determining ′ is:

[0196]

[0197] Where, p DHinnew ′ represents the inlet steam pressure of the heating network heater after the heating extraction steam flow rate is adjusted, Kcr represents the critical pressure ratio of superheated steam, and p IPexh ′ represents the exhaust pressure of the intermediate-pressure cylinder during normal heating operation, F CNnew ′ represents the heating steam supply flow rate after adjustment of the heating extraction steam flow rate, p ipex-set These are the set values ​​for all test conditions.

[0198] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0199] Those skilled in the art will recognize that the templates, units, and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0200] If the module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium. When executed by a processor, the computer program can implement the steps of the flow control method embodiments for the heating steam regulating valves of the various heating units described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory, a random access memory, an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0201] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for controlling the flow rate of a heating steam supply regulating valve in a heating unit, characterized in that, include: Based on the design heat balance diagram provided by the turbine manufacturer, the corresponding data of low-pressure cylinder inlet steam flow rate and low-pressure cylinder inlet steam pressure under multiple design conditions are summarized, and a first fitting function of low-pressure cylinder inlet steam flow rate and low-pressure cylinder inlet steam pressure is obtained; based on the first fitting function and the low-pressure cylinder inlet steam pressure under different heating steam supply flow rate conditions, the low-pressure cylinder inlet steam flow rate under different heating steam supply flow rate conditions is calculated. Based on the low-pressure cylinder inlet steam flow rate under different heating steam supply flow conditions, the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve is determined. Based on the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve and the opening data of the connecting pipe heating regulating butterfly valve under multiple heating and steam supply flow conditions, a first characteristic curve is obtained by fitting. Based on the outlet water temperature of the heating network heater under different heating steam supply flow conditions, the inlet steam pressure of the heating network heater under different heating steam supply flow conditions is calculated; based on the inlet steam pressure of the heating network heater under different heating steam supply flow conditions, the characteristic flow coefficient of the heating steam supply regulating valve is determined; based on the characteristic flow coefficient of the heating steam supply regulating valve and the opening data of the heating steam supply regulating valve under multiple heating steam supply flow conditions, a second characteristic curve is obtained by fitting. Calculate the corresponding low-pressure cylinder inlet steam flow rate based on the low-pressure cylinder inlet steam pressure under normal heating operation conditions of the target heating unit. Calculate the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve after the heating extraction steam flow rate is adjusted, and the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve is corrected to the test state. Based on the first characteristic curve and the flow coefficient of the connecting pipe heating regulating butterfly valve corrected to the test state, the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating steam extraction flow is determined. Based on the circulating water volume of the heating network and the adjustment amount of the heating extraction steam flow under the normal heating operation conditions of the target heating unit, determine the new outlet temperature of the heating network heater; based on the new outlet temperature of the heating network heater, determine the characteristic flow coefficient of the heating steam supply regulating valve after the adjustment of the heating extraction steam flow, and the characteristic flow coefficient of the heating steam supply regulating valve corrected to the test state. Based on the second characteristic curve and the modified flow coefficient of the heating steam supply regulating valve, the opening degree of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating steam extraction flow rate is determined. Based on the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, the opening degree of the heating supply steam regulating valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, and the preset opening degree range, the opening degree of the connecting pipe heating regulating butterfly valve and the heating supply steam regulating valve are determined respectively.

2. The flow control method for the heating steam supply regulating valve of the heating unit according to claim 1, characterized in that, The characteristic flow coefficient of the connecting pipe heating regulating butterfly valve The formula for determining it is: when hour, ； when hour, ； in, Let be the steam inlet flow rate of the i-th heating steam supply cylinder. Let be the exhaust pressure of the intermediate-pressure cylinder for the i-th heating steam supply. Kcr is the inlet steam pressure of the low-pressure cylinder for the i-th heating steam supply, and Kcr is the critical pressure ratio of superheated steam.

3. The flow control method for the heating steam supply regulating valve of the heating unit according to claim 1, characterized in that, The characteristic flow coefficient of the heating and steam supply regulating valve for: when hour, ； when hour, ； in, Let be the heating steam supply flow rate for the i-th heating system. Let be the exhaust pressure of the intermediate-pressure cylinder for the i-th heating steam supply. Let Kcr be the inlet steam pressure of the heater in the i-th heating network, and Kcr be the critical pressure ratio of superheated steam.

4. The flow control method for the heating steam supply regulating valve of the heating unit according to claim 1, characterized in that, The characteristic flow coefficient of the connecting pipe heating regulating butterfly valve after the heating steam extraction flow rate is adjusted The formula for determining it is: when hour, ； when hour, ； Corrected flow coefficient of the connecting pipe heating regulating butterfly valve under test conditions for: ； in, Kcr is the inlet steam pressure of the low-pressure cylinder after the heating steam extraction flow rate is adjusted, and Kcr is the critical pressure ratio of superheated steam. This is the exhaust pressure of the intermediate pressure cylinder during normal heating operation. This represents the steam inlet flow rate of the low-pressure cylinder during normal heating operation. These are the set values ​​for all test conditions.

5. The flow control method for the heating steam supply regulating valve of the heating unit according to claim 1, characterized in that, The characteristic flow coefficient of the heating steam supply regulating valve after the heating steam extraction flow rate is adjusted. The formula for determining it is: when hour, ； when hour, ； The corrected flow coefficient of the heating and steam supply regulating valve under test conditions The formula for determining it is: ； in, Kcr is the inlet steam pressure of the heating network heater after the heating extraction steam flow rate is adjusted, and Kcr is the critical pressure ratio of superheated steam. This is the exhaust pressure of the intermediate-pressure cylinder during normal heating operation. This refers to the heating steam supply flow rate after the heating extraction steam flow rate has been adjusted. These are the set values ​​for all test conditions.

6. A flow control device for a heating steam supply regulating valve of a heating unit, characterized in that, include: The first curve determination module is used to summarize the corresponding data of low-pressure cylinder inlet steam flow and low-pressure cylinder inlet steam pressure under multiple design conditions based on the design heat balance diagram provided by the turbine manufacturer, and to fit a first fitting function of low-pressure cylinder inlet steam flow and low-pressure cylinder inlet steam pressure; based on the first fitting function and the low-pressure cylinder inlet steam pressure under different heating steam supply flow conditions, the low-pressure cylinder inlet steam flow is calculated under different heating steam supply flow conditions. Based on the low-pressure cylinder inlet steam flow rate under different heating steam supply flow conditions, the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve is determined. Based on the characteristic flow coefficient and opening data of the connecting pipe heating regulating butterfly valve under multiple heating and steam supply flow conditions, a first characteristic curve is obtained by fitting. The second curve determination module is used to calculate the inlet steam pressure of the heating network heater under different heating steam supply flow conditions based on the outlet water temperature of the heating network heater under different heating steam supply flow conditions; determine the characteristic flow coefficient of the heating steam supply regulating valve based on the inlet steam pressure of the heating network heater under different heating steam supply flow conditions; and fit the characteristic flow coefficient of the heating steam supply regulating valve and the opening data of the heating steam supply regulating valve under multiple heating steam supply flow conditions to obtain the second characteristic curve. The first opening determination module is used to calculate the corresponding low-pressure cylinder inlet steam flow rate based on the low-pressure cylinder inlet steam pressure under the normal heating operation conditions of the target heating unit. Calculate the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve after the heating extraction steam flow rate is adjusted, and the characteristic flow coefficient of the connecting pipe heating regulating butterfly valve is corrected to the test state. Based on the first characteristic curve and the flow coefficient of the connecting pipe heating regulating butterfly valve corrected to the test state, the opening degree of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating steam extraction flow is determined. The second opening determination module is used to determine the new heating network heater outlet temperature based on the heating network circulating water volume and heating steam extraction flow rate adjustment under the normal heating operation conditions of the target heating unit; and based on the new heating network heater outlet temperature, to determine the characteristic flow coefficient of the heating steam supply regulating valve after the heating steam extraction flow rate adjustment, as well as the characteristic flow coefficient of the heating steam supply regulating valve corrected to the test state. Based on the second characteristic curve and the modified flow coefficient of the heating steam supply regulating valve, the opening degree of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating steam extraction flow rate is determined. The final value determination module is used to determine the opening of the connecting pipe heating regulating butterfly valve and the heating steam supply regulating valve based on the opening of the connecting pipe heating regulating butterfly valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, the opening of the heating steam supply regulating valve corresponding to the predetermined adjustment amount of the heating extraction steam flow, and the preset opening range.

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