Real-time calculation method and device for upspin reserve capacity of coal-fired unit

Abstract

The invention relates to a real-time calculation method and device for the upspin reserve capacity of a coal-fired unit, and the method comprises the steps: obtaining the equipment composition of the coal-fired unit, and analyzing the equipment type and equipment parameters of each piece of equipment; analyzing whether corresponding equipment has operation defects according to the equipment type of the coal-fired unit; according to the equipment parameters, a first limited constraint, a second limited constraint and a third limited constraint are obtained through calculation; and analyzing according to the first limited constraint, the second limited constraint and the third limited constraint to obtain the upspin reserve capacity of the coal-fired unit. According to the method, limiting factors influencing the upspin reserve capacity of the coal-fired unit, such as equipment defects, unit operation limitation, boiler output limitation and steam turbine output limitation, are fully considered, and quantitative calculation of the upspin reserve capacity of the coal-fired unit is realized. The method can accurately obtain the upspin reserve capacity result of the coal-fired unit, improves the evaluation precision of the result, and guarantees the stability of a power grid.

Description

Technical Field

[0001] The present application relates to the technical field of coal-fired unit operation monitoring, and in particular to a real-time calculation method and device for the rotational spare capacity of a coal-fired unit. Background Art

[0002] In the context of the current new power system, coal-fired units are generally transformed for flexibility. With the massive access to new energy sources, the operation curve of coal-fired units presents wide load and rapid operation characteristics. However, with the improvement of operational flexibility, coal-fired units also have the defect of insufficient peak capacity, that is, the output of coal-fired units does not reach the rated load, which means that the upper rotation reserve capacity of coal-fired units is less than expected. Since the upper rotation reserve capacity of coal-fired units does not meet expectations, it will make it difficult for the power system to maintain power balance in the face of a large-scale disconnection of new energy sources or insufficient output of new energy sources, which directly leads to emergency accidents such as power outages. In addition, due to the inability to obtain high-quality and stable coal, the coal quality of coal-fired units deviates from the designed coal type and is complex and changeable, which further aggravates the situation that the upper rotation capacity of coal-fired units is less than expected.

[0003] However, the current evaluation of the spinning reserve capacity of coal-fired units is mainly based on the experience of power plant operators, and there is a lack of relevant theoretical research. Since there are many factors that actually affect the spinning reserve capacity of coal-fired units and there is a lack of systematic and theoretical analysis, it is difficult to achieve an accurate evaluation of the spinning reserve capacity by relying on the experience of operators, and it is impossible to ensure the power stability of the power grid. Summary of the invention

[0004] In order to overcome the above-mentioned deficiencies of the prior art, the present application provides a real-time calculation method and device for the upper rotation reserve capacity of a coal-fired unit, which specifically adopts the following technical solutions:

[0005] A real-time calculation method for the spinning reserve capacity of a coal-fired unit comprises the following steps:

[0006] Obtaining the equipment composition of the coal-fired unit and analyzing the equipment type and equipment parameters of each equipment; the equipment type of the coal-fired unit includes key equipment and auxiliary equipment;

[0007] Analyze whether the corresponding equipment has operating defects according to the equipment type of the coal-fired unit: when any key equipment has operating defects, the upper rotation reserve capacity of the coal-fired unit is 0; when only the auxiliary equipment has operating defects or no equipment has operating defects, proceed to the next step;

[0008] The first restricted constraint, the second restricted constraint and the third restricted constraint are calculated and obtained according to the equipment parameters; wherein the first restricted constraint includes the output restriction of the unit; the second restricted constraint includes the output restriction of the pulverizing system, the output restriction of the fan and the environmental protection restriction; the third restricted constraint includes the output restriction caused by the heating demand and the output restriction caused by the excessively high cold end parameters;

[0009] The spin-up reserve capacity of the coal-fired unit is obtained by analysis based on the first restricted constraint, the second restricted constraint and the third restricted constraint.

[0010] Optionally: the step of calculating and obtaining the first restricted constraint according to the device parameters includes:

[0011] Obtain the operating defects of each device in the fuel-fired unit and the load status of the unit;

[0012] When there are no defects in the equipment of the coal-fired unit or only the auxiliary equipment has defects, determine whether the coal-fired unit is in a variable load state;

[0013] When the coal-fired unit is not in a variable load state, the unit output limitation is calculated based on the rated power and current operating power of the coal-fired unit;

[0014] When the coal-fired unit is in a variable load state, the unit output limitation is calculated based on the variable load rate setting value and the variable load time of the coal-fired unit at different times;

[0015] The first restricted constraint is obtained according to the limited output calculation of the unit.

[0016] Optionally, the step of calculating and obtaining the first restricted constraint according to the limited output of the unit includes:

[0017] Obtain the output limitation of coal-fired units in variable load state or not in variable load state;

[0018] Based on the upper spin reserve capacity P of coal-fired units U,T Must be less than or equal to the unit output limit P 机组 , obtain the first restricted constraint A1 of the coal-fired unit, that is, A1≤P 机组 .

[0019] Optionally: the step of obtaining the second restricted constraint by calculating the device parameters includes:

[0020] Obtaining equipment parameters of a pulverizing system, a fan, and a desulfurization system in a coal-fired unit; wherein the equipment parameters include at least the actual coal feed rate of the pulverizing system, the maximum operating coal feed rate of the pulverizing system, the maximum designed total air volume of the fan, the actual air volume of the fan, and the maximum sulfur dioxide flow rate allowed by the desulfurization system;

[0021] The output limitation of the pulverizing system is calculated based on the maximum operating coal supply of the pulverizing system and the current actual coal supply;

[0022] The fan output limitation is calculated based on the maximum designed total air volume of the fan and the current actual air volume;

[0023] The environmental protection limit is calculated based on the maximum sulfur dioxide flow allowed by the desulfurization system and the sulfur content in the medium test results;

[0024] The second constraint is obtained according to the limited output of the powder making system, the limited output of the fan and the limited environmental protection.

[0025] Optionally, the step of obtaining the second constraint according to the limited output of the milling system, the limited output of the fan and the limited environmental protection includes:

[0026] Obtain the results of the output limitation of the pulverizing system, the output limitation of the fan and the environmental protection limitation in the coal-fired unit;

[0027] The minimum value function is used to calculate the output limitation of the pulverizing system, the fan output limitation and the environmental protection limitation to obtain the output limitation of the boiler system P 锅炉 ;

[0028] Based on the upper spin reserve capacity P of coal-fired units U,T Must be less than or equal to the boiler system output limit P 锅炉 , and obtain the second restricted constraint A2 of the coal-fired unit, that is, A2≤P 锅炉 .

[0029] Optionally: the step of obtaining the third restricted constraint by calculating the device parameters includes:

[0030] Obtaining equipment parameters of a steam turbine in a coal-fired unit; wherein the equipment parameters of the steam turbine at least include heat extraction steam flow, ambient temperature, and turbine work efficiency coefficient under rated conditions, low-pressure cylinder steam work coefficient, and main steam operating conditions; wherein the main steam operating conditions at least include main steam temperature, main steam flow, and main steam pressure;

[0031] The output limitation caused by the heating demand is calculated based on the heating extraction steam flow rate of the steam turbine, the steam work coefficient of the low-pressure cylinder and the current operating power;

[0032] The output limitation due to excessively high cold end parameters is calculated based on the turbine work efficiency coefficient, main steam operating conditions and current operating power of the steam turbine;

[0033] The third limiting constraint is obtained according to the output limitation caused by the heating demand and the output limitation caused by the excessively high cold end parameters.

[0034] Optionally, the step of obtaining the third limiting constraint according to the output limitation caused by the heating demand and the output limitation caused by the excessively high cold end parameters includes:

[0035] Obtain the results of output limitation caused by heating demand and output limitation caused by excessive cold end parameters in coal-fired units;

[0036] The output limitation caused by the heating demand and the output limitation caused by the excessive cold end parameters are calculated using the minimum function to obtain the turbine output limitation P. 汽轮机 ;

[0037] Based on the upper spin reserve capacity P of coal-fired units U,T Must be less than or equal to the turbine output limit P 汽轮机 , and obtain the third restricted constraint A3 of the coal-fired unit, that is, A3≤P 汽轮机 .

[0038] Optionally, the step of analyzing and obtaining the spin-up reserve capacity of the coal-fired unit according to the first restricted constraint, the second restricted constraint and the third restricted constraint includes:

[0039] Obtaining the first restricted constraint, the second restricted constraint and the third restricted constraint results of the coal-fired unit;

[0040] Calculate the spin-up reserve capacity of coal-fired units based on the minimum function:

[0041] P U,T =min(A1,A2,A3);

[0042] Where P U,T is the spin-up reserve capacity of the coal-fired unit; A1 is the first restricted constraint result of the coal-fired unit; A2 is the second restricted constraint result of the coal-fired unit; A3 is the third restricted constraint result of the coal-fired unit.

[0043] Furthermore, the present application also discloses a real-time calculation device for the rotational reserve capacity of a coal-fired unit, the device comprising:

[0044] A parameter acquisition module is used to acquire the equipment composition of the coal-fired unit and analyze the equipment type, operating parameters and design parameters of each equipment; the equipment type of the coal-fired unit includes key equipment and auxiliary equipment;

[0045] The defect analysis module is used to analyze whether the corresponding equipment has operating defects according to the equipment type of the coal-fired unit: when any key equipment has operating defects, the upper rotation reserve capacity of the coal-fired unit is 0; when only the auxiliary equipment has operating defects or no equipment has operating defects, proceed to the next step;

[0046] A constraint calculation module, used to calculate the first constraint, the second constraint and the third constraint according to the equipment parameters; wherein the first constraint includes the unit output constraint; the second constraint includes the powder making system output constraint, the fan output constraint and the environmental protection constraint; the third constraint includes the output constraint caused by the heating demand and the output constraint caused by the excessively high cold end parameters;

[0047] The capacity calculation module is used to analyze and obtain the spin-up reserve capacity of the coal-fired unit according to the first restricted constraint, the second restricted constraint and the third restricted constraint.

[0048] Beneficial Effects

[0049] The technical solution of this application has the following beneficial effects:

[0050] The real-time calculation method of the present application realizes the quantitative calculation of the spinning reserve capacity of the coal-fired unit by fully considering the limiting factors affecting the spinning reserve capacity of the coal-fired unit, such as equipment defects, limited unit operation, limited boiler output and limited turbine output. This method fully considers a variety of influencing factors and can accurately obtain the spinning reserve capacity results of the coal-fired unit, improve the evaluation accuracy of the results, and thus ensure the stability of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a flow chart of a real-time calculation method of the spinning-up spare capacity of a coal-fired unit in an embodiment of the present application.

[0052] Figure 2 This is a schematic diagram of factors affecting the spin-up spare capacity of a coal-fired unit in an embodiment of the present application.

[0053] Figure 3 This is a schematic diagram of calculating the spin-up reserve capacity of a coal-fired unit based on a minimum function in an embodiment of the present application.

[0054] Figure 4 Schematic diagram of the state of a coal-fired unit affected by the load increase rate in an embodiment of the present application, wherein Figure 4 (a) is a schematic diagram of the load change of the coal-fired unit in this embodiment when the load is increased. Figure 4 (b) is a diagram showing the change in the upward rotation reserve capacity of the coal-fired unit in this embodiment under load increase conditions.

[0055] Figure 5 Schematic diagram of the state of a coal-fired unit affected by the unit heating steam extraction constraint in the embodiment of the present application, wherein Figure 5 (a) is a schematic diagram of unit load changes of the coal-fired unit in this embodiment under the unit heating steam extraction constraint. Figure 5 (b) is a diagram showing the variation of the upward rotation reserve capacity of the coal-fired unit in this embodiment under the constraints of the unit's heating and steam extraction.

[0056] Figure 6 It is a structural diagram of a real-time calculation device for the rotational spare capacity of a coal-fired unit in an embodiment of the present application.

[0057] Figure 7 This is a structural diagram of an electronic device in an embodiment of the present application. DETAILED DESCRIPTION

[0058] The present application is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and cannot be used to limit the scope of protection of the present application. It should be noted that the following detailed descriptions are all exemplary and are intended to provide further explanation of the present application.

[0059] The spin-up reserve capacity of coal-fired units refers to the additional capacity of coal-fired units that can increase the output power in a short period of time on the basis of normal operating power generation capacity. This additional capacity can be regarded as a kind of reserve power of coal-fired units to quickly respond to changes in the demand of the power grid. During the operation of the power grid, the power load changes dynamically. When the peak of power consumption comes or some generators suddenly fail and shut down, the spin-up reserve capacity can be quickly put into use to fill the power gap and maintain the stability of the power grid frequency and voltage. For example, in the hot summer, a large number of air-conditioning equipment are turned on at the same time, and the load of the power grid rises sharply. At this time, the spin-up reserve capacity of coal-fired units can quickly increase the power generation power and avoid accidents such as power outages. In addition, it can cope with some unforeseen situations, such as extreme weather causing a sharp drop in the output power of some renewable energy generators (such as wind power generation and photovoltaic power generation). The spin-up reserve capacity of coal-fired units can be quickly started in this case to ensure the safe and reliable operation of the power grid.

[0060] Combination Figure 1 and 2 As shown, the factors that generally affect the rotation reserve capacity of coal-fired units can be classified into four categories: the first category is equipment defects, the second category is limited unit operating parameters, the third category is limited boiler system output, and the fourth category is limited turbine output. Furthermore, the embodiment of the present application specifically discloses a real-time calculation method for the rotation reserve capacity of a coal-fired unit, which includes the following steps:

[0061] Step 1: Obtain the equipment composition of the coal-fired unit, and analyze the equipment type and equipment parameters of each equipment; the equipment type of the coal-fired unit includes key equipment and auxiliary equipment. Generally, the key equipment in the coal-fired unit includes a pulverizing system, a blower, a water pump, a boiler system, a steam turbine system, etc. This type of equipment needs to be operated during the unit's load change process and has a great impact on the unit's load. Auxiliary equipment includes chemical water treatment equipment, a standby coal mill, etc. This type of equipment does not participate in or has a very small impact on the unit's load change process; it should be noted that the equipment parameters described in the embodiment of the present application at least include actual coal feed, operating power, actual air volume, sulfur content in the medium test results, variable load rate setting value, heating pumping flow, ambient temperature, variable load time, maximum operating coal feed of the pulverizing system, designed maximum total air volume, rated power, main steam operating conditions under rated conditions, maximum SO2 flow allowed by the desulfurization system, low-pressure cylinder work efficiency, and turbine work efficiency coefficient.

[0062] Step 2: Analyze whether the corresponding equipment has operation defects according to the equipment type of the coal-fired unit: When any key equipment has operation defects, the upper rotation spare capacity of the coal-fired unit is 0; when only the auxiliary equipment has operation defects or no equipment has operation defects, proceed to the next step; It should be noted that in this step 2, the operation status of the key equipment and the auxiliary equipment are analyzed separately. Generally, if the defective equipment is a key equipment that needs to be operated during the load change process, such as the pulverizing system, blower, and water pump of the coal-fired unit, the coal-fired unit will not have the ability to increase the load before the defect is eliminated, and will no longer have the upper rotation spare capacity, and the unit will even face shutdown for maintenance. If the defective equipment is an auxiliary equipment such as chemical water treatment equipment and spare coal mill that does not affect the load increase during load change, since the auxiliary equipment has limited impact on the load change of the unit, the coal-fired unit still has a certain upper rotation spare capacity. At this time, further analysis can be conducted on the upper rotation spare capacity of the coal-fired unit.

[0063] Step 3: Calculate the first constraint, the second constraint and the third constraint according to the equipment parameters; wherein the first constraint includes the unit output limitation; the second constraint includes the powder making system output limitation, the fan output limitation and the environmental protection limitation; the third constraint includes the output limitation caused by the heating demand and the output limitation caused by the excessively high cold end parameters;

[0064] Step 4: Analyze and obtain the spin-up reserve capacity of the coal-fired unit according to the first constraint, the second constraint and the third constraint.

[0065] Specifically, the step of obtaining the first restricted constraint according to the device parameter calculation described in the embodiment of the present application includes:

[0066] (1) Obtain the operating defects of each device in the fuel-fired unit and the load status of the unit;

[0067] (2) When there are no defects in the equipment of the coal-fired unit or only the auxiliary equipment has defects, determine whether the coal-fired unit is in a variable load state;

[0068] (3) When the coal-fired unit is not in a variable load state, according to the rated power P of the coal-fired unit e and the current operating power P c The calculated unit output limit is P 机组 =P e -P c , where the rated power of coal-fired units is P e The unit is MW, the operating power P c The unit is MW. At this time, the maximum spin-up reserve capacity of the coal-fired unit is restricted by the rated power of the unit, and the factors affecting the spin-up reserve capacity of the coal-fired unit are mainly attributed to the limited boiler output and the limited turbine output.

[0069] (4) When the coal-fired unit is in a variable load state, the unit output limit is calculated as P according to the variable load rate setting value C and the variable load time T of the coal-fired unit at different times. 机组 =C×T; the unit of variable load rate setting value C is MW / min, and the unit of variable load time T is min. Generally, when the coal burning of a unit is limited by the variable load rate, the spin-up reserve capacity in the future will inevitably be less than the constraints of the variable load rate and time, and the maximum spin-up reserve capacity is restricted by the rated power of the unit.

[0070] (5) Finally, the first constraint is obtained based on the unit output limitation calculation:

[0071] a. First, obtain the unit output limit P of the coal-fired unit in a variable load state or not in a variable load state. 机组 ;

[0072] b. Based on the spin-up reserve capacity P of coal-fired units U,T Must be less than or equal to the unit output limit P 机组 , obtain the first restricted constraint A1 of the coal-fired unit, that is, A1≤P 机组 .

[0073] Further, the output limitation of the boiler system is analyzed in this application. It can be known that the factors limiting the output of the boiler system are mainly coal supply limitation, air supply output limitation, and environmental protection limitation. Among them, the coal supply limitation refers to the coal-fired unit using low calorific value coal, which causes the output of the pulverizer to reach the upper limit and cannot continue to increase the output. However, at this time, the coal-fired unit has not yet obtained enough heat, resulting in the unit output not reaching the rated output. The air supply output limitation refers to the use of low calorific value coal. In order to achieve the rated output of the unit, the coal supply is gradually increased. Due to the fixed wind-coal ratio function, the blower equipment reaches the rated output and cannot provide more output. At this time, the unit output is limited. The most prominent environmental protection limitation is the desulfurization requirement limitation, which means that as the sulfur element in the coal quality increases, the sulfur dioxide in the flue gas gradually increases. The desulfurization tower has a certain upper limit on the removal capacity of SO2 per unit time, and it is impossible to remove SO2 by infinitely increasing lime water. Otherwise, the SO2 at the flue gas outlet will increase, which does not meet the environmental protection requirements and causes pollutant emissions to exceed the standard. Therefore, the step of obtaining the second restricted constraint according to the device parameter calculation described in this application includes:

[0074] (1) obtaining equipment parameters of a pulverizing system, a fan, and a desulfurization system in a coal-fired unit; wherein the equipment parameters include at least an actual coal feed rate of the pulverizing system, a maximum operating coal feed rate of the pulverizing system, a maximum designed total air volume of the fan, an actual air volume of the fan, and a maximum sulfur dioxide flow rate allowed by the desulfurization system;

[0075] (2) According to the maximum operating coal feed rate R of the pulverizing system max And the current actual coal supply R C The output limit of the milling system is calculated to be P 制粉 =(R max / R C -1)P C ; The maximum operating coal supply R max The unit is t / h, the actual coal feed rate R C The unit is t / h. Since there is an upper limit to the amount of coal that can be processed by the pulverizing system (generally a coal mill), and the coal currently used is low-quality coal, the actual coal feed and the unit load cannot operate according to the design value. Therefore, based on the limitation of the coal feed on the upper rotation reserve capacity, the upper rotation reserve capacity of the coal-fired unit must be limited by the output of the pulverizing system, that is, the upper rotation reserve capacity of the coal-fired unit is less than or equal to the output limit of the pulverizing system P. 制粉 .

[0076] (3) Based on the maximum design total air volume W of the fan max and the current actual air volume W C The fan output limit is calculated as P 风机 =(W max / W C -1)P C; The maximum designed total air volume W max The unit is t / h; the actual air volume W C The unit is t / h. Similarly, the total air volume that can be provided by the fan and other equipment in this application also has a certain upper limit. If the coal quality or environmental conditions are restricted, resulting in the fan output cannot be further increased, the fan output will restrict the upward rotation reserve capacity, that is, the upward rotation reserve capacity of the coal-fired unit is less than or equal to the fan output limit P 风机 .

[0077] (4) According to the maximum sulfur dioxide flow rate D allowed by the desulfurization system L The sulfur content L in the medium test results is calculated to obtain the environmental protection limit P 环保 =(D L / R C L%-1)P C ; The maximum sulfur dioxide flow rate D L The unit is t / h, the actual coal feed rate R C The unit is t / h. Since the desulfurization system has a certain upper limit on the flow rate of desulfurized and denitrified flue gas, once the flow rate is too large, pollutant emissions will exceed the standard, affecting the assessment of power generation pollutants. According to the law of conservation of elements, the maximum amount of coal allowed by the current coal quality is D L / L%, then under the current coal quality, due to the restriction of the desulfurization system processing capacity, the upper rotation reserve capacity of the coal-fired unit is limited, that is, the upper rotation reserve capacity of the coal-fired unit is less than or equal to the environmental protection limit P 环保 .

[0078] (5) The second constraint is obtained based on the limited output of the milling system, the limited output of the fan, and the limited environmental protection:

[0079] a. Obtain the output limit P of the pulverizing system in the coal-fired unit 制粉 , fan output is limited P 风机 And environmental restrictions 环保 Result;

[0080] b. Use the minimum value function to calculate the output limitation of the pulverizing system, the fan output limitation and the environmental protection limitation to obtain the output limitation of the boiler system P. 锅炉 :

[0081] P 锅炉 =min(P 制粉 ,P 风机 ,P 环保 );

[0082] c. Based on the upper spin reserve capacity P of coal-fired units U,T Must be less than or equal to the boiler system output limit P 锅炉 , and obtain the second restricted constraint A2 of the coal-fired unit, that is, A2≤P锅炉 It should be noted that since the factors limiting the output of the boiler system are mainly the coal supply limit, the air supply output limit, and the environmental protection limit, the output of the boiler system is limited. 锅炉 The output of the milling system must be limited P 制粉 , fan output is limited P 风机 And environmental restrictions 环保 , that is, the output limit of the boiler system is less than or equal to the output limit of the powder making system P 制粉 , fan output is limited P 风机 And environmental restrictions 环保 Based on the above conditions, only the output limit of the milling system P needs to be selected. 制粉 , fan output is limited P 风机 And environmental restrictions 环保 The minimum value of the three is taken as the boiler system output limit P 锅炉 , when the boiler system output is limited P 锅炉 When the value is less than or equal to the minimum value, the upper rotation reserve capacity of the coal-fired unit must also meet the output limit of the pulverizing system P 制粉 , fan output is limited P 风机 And environmental restrictions 环保 restrictions.

[0083] Furthermore, the embodiment of the present application analyzes the limitation of steam turbine output, and it can be known that the factors limiting the output of steam turbine are mainly heat extraction limitation and cold end parameter limitation. Among them, the heat extraction limitation means that in order to meet the heating requirements, the heating unit must separate a certain flow of steam for heating, but the main steam flow of the coal-fired unit has an upper limit, which causes the steam used for work to have a certain upper limit as the heating amount changes. Based on the heat load, the power generation capacity of the unit will be limited, and the upper limit of the steam flow will also be limited. The cold end parameter limitation is mainly attributed to the back pressure of the air-cooling island of the air-cooling unit. When the ambient temperature is high, the saturation pressure is also high, resulting in a decrease in the enthalpy drop of steam entering the turbine, which in turn leads to the limitation of the unit output. Specifically, the steps of obtaining the third limiting constraint according to the equipment parameter calculation described in the present application include:

[0084] (1) obtaining equipment parameters of a steam turbine in a coal-fired unit; wherein the equipment parameters of the steam turbine at least include heat extraction steam flow, ambient temperature, and turbine work efficiency coefficient under rated conditions, low-pressure cylinder steam work coefficient, and main steam operating conditions; wherein the main steam operating conditions at least include main steam temperature, main steam flow, and main steam pressure;

[0085] (2) According to the steam turbine heat extraction flow rate D x , low pressure cylinder steam work coefficient η e And the current operating power P CThe output limitation caused by the heating demand is calculated as P 供热 =P e -D x η e -P C ; Among them, the heating steam flow D x The unit is t / h, the rated power of the coal-fired unit P e The unit is MW, the operating power P c The unit is MW. Due to the influence of the unit heating factor, a part of the steam extraction in the steam turbine will go from the low-pressure cylinder to the heating. This part of steam will cause the loss of steam turbine power, and the loss is D x η e At the same time, the steam flow of the steam turbine has an upper limit, so that the upward rotation reserve capacity of the coal-fired unit is limited by the steam flow of the steam turbine that is not heating, that is, the upward rotation reserve capacity of the coal-fired unit is less than or equal to the output limit P caused by the heating demand. 供热 .

[0086] (3) Based on the turbine efficiency coefficient η, main steam operating conditions (main steam temperature T st , Main steam flow D max And the main steam pressure P st ) and the current operating power P C Calculate the output limitation P caused by excessive cold end parameters 冷端 =η(f(P st ,T st )-f(T1))D max -P C ; where f is the thermodynamic characteristic function of water and steam calculated according to IAPWS-IF97, the main steam temperature T st The unit is ℃, the main steam flow rate D max The unit is t / h, the main steam pressure P st The unit is MPa, operating power P C The unit is MW, T1 is the ambient temperature, the unit is ℃. Since the enthalpy of steam entering the steam turbine has an impact on the unit output, the enthalpy of steam entering the steam turbine under rated conditions is calculated as f(P st ,T st ), f is the thermodynamic property of water and water vapor, and the enthalpy value can be calculated according to the temperature and pressure. When the current ambient temperature changes, the cold end parameters also change, especially for air-cooled units, whose enthalpy value of cold end parameters is f(T1), which is the saturated enthalpy value at the current temperature. The upper spin reserve capacity of the coal-fired unit is affected by the change of cold end parameters, that is, the upper spin reserve capacity of the coal-fired unit is less than or equal to the output limitation P caused by the excessive cold end parameters. 冷端 .

[0087] (4) The third constraint is obtained according to the output limitation caused by the heating demand and the output limitation caused by the excessively high cold end parameters:

[0088] a. Obtain the output limitation P caused by the heating demand in the coal-fired unit 供热 And the output is limited due to the high cold end parameters P 冷端 Result;

[0089] b. Use the minimum value function to calculate the output limitation caused by the heating demand and the output limitation caused by the excessive cold end parameters to obtain the turbine output limitation P 汽轮机 =min(P 供热 ,P 冷端 );

[0090] c. Based on the upper spin reserve capacity P of coal-fired units U,T Must be less than or equal to the turbine output limit P 汽轮机 , and obtain the third restricted constraint A3 of the coal-fired unit, that is, A3≤P 汽轮机 It should be noted that since the factors limiting the steam turbine output are mainly the heat extraction steam limit and the cold end parameter limit, the steam turbine output is limited by P 汽轮机 The output is limited due to the need to meet the heating demand at the same time 供热 And the output is limited due to the high cold end parameters P 冷端 , that is, the turbine output limitation is less than or equal to the output limitation caused by the heating demand P 供热 And the output is limited due to the high cold end parameters P 冷端 Based on the above conditions, only the output limit P caused by the heating demand needs to be selected. 供热 And the output is limited due to the high cold end parameters P 冷端 The minimum value of the two is taken as the turbine output limit P 汽轮机 , when the turbine output is limited P 汽轮机 When the value is less than or equal to the minimum value, the upper rotation reserve capacity of the coal-fired unit must also meet the output limitation caused by the heating demand P 供热 And the output is limited due to the high cold end parameters P 冷端 restrictions.

[0091] Finally, the step of analyzing and obtaining the spin-up reserve capacity of the coal-fired unit according to the first constraint, the second constraint and the third constraint in step 4 of the present application includes:

[0092] (1) Obtaining the first constraint, the second constraint, and the third constraint results of the coal-fired unit;

[0093] (2) Calculate the spin-up reserve capacity of coal-fired units based on the minimum function:

[0094] P U,T=min(A1,A2,A3);

[0095] Where P U,T is the spin-up reserve capacity of the coal-fired unit; A1 is the first restricted constraint result of the coal-fired unit; A2 is the second restricted constraint result of the coal-fired unit; A3 is the third restricted constraint result of the coal-fired unit.

[0096] It should be noted that when analyzing the first constraint, the second constraint and the third constraint based on the minimum value function in step 4, the essence is to select the minimum value among the first constraint, the second constraint and the third constraint, such as Figure 3 As shown, that is:

[0097]

[0098] Taking this minimum value as the final coal-fired unit's spinning reserve capacity constraint can ensure that the final coal-fired unit's spinning reserve capacity value meets the constraint range under the influence of four factors: equipment defects, limited unit operating parameters, limited boiler system output, and limited turbine output, so as to fully consider the factors affecting output and thus improve the evaluation accuracy.

[0099] The present application embodiment is verified and explained using a 350MW supercritical heating unit, wherein some design parameters of the unit are shown in Table 1 below:

[0100] Table 1

[0101] Parameter Type Numeric unit <![CDATA[Rated power P e > 350 MW <![CDATA[Rated main steam pressure P st > 24.2 MPa <![CDATA[Rated main steam temperature T st > 566 ℃ Rated main steam flow Dmax 1005 t / h <![CDATA[Maximum operating coal feeding rate R C > 170 t / h <![CDATA[Maximum total air volume W max > 1300 t / h <![CDATA[Low-pressure cylinder work efficiency coefficient η e > 0.139 MW / (t / h) Steam turbine efficiency coefficient η 0.348 MW / (t / h)

[0102] Based on the historical operating data of the coal-fired unit, the calculation of the unit's spin-up reserve capacity under the influence of the unit's load increase rate limitation and the unit's heating factors is taken as an example.

[0103] Combination Figure 4 As shown, it is a schematic diagram of the unit state of the coal-fired unit in this embodiment affected by the load increase rate, wherein Figure 4 (a) is a schematic diagram of the load change of the coal-fired unit in this embodiment when the load is increased. Figure 4 (b) is a graph showing the change in the spin-up reserve capacity of the coal-fired unit in this embodiment under load increase. In this embodiment, the current load change rate setting value C = 7MW / min; the load change time is T = 2.8min. The spin-up reserve capacity of the coal-fired unit is calculated as:

[0104] C×T=7MW / min×2.8min=19.6MW

[0105] At this time, the upper rotation reserve capacity of the coal-fired unit is 19.6MW.

[0106] Combination Figure 5As shown, it is a schematic diagram of the unit state of the coal-fired unit in this embodiment affected by the unit heating steam extraction constraint, where Figure 5 (a) is a schematic diagram of unit load changes of the coal-fired unit in this embodiment under the unit heating steam extraction constraint. Figure 5 (b) is a graph showing the change in the upward rotation reserve capacity of the coal-fired unit under the constraints of the unit's heat extraction steam. In this embodiment, the heat extraction steam flow rate is set to: D x =41.91t / h; Actual coal supply of the current unit: R c =160t / h; Current unit operating power: P c =280MW. Then the calculation of the upper rotation reserve capacity of the coal-fired unit is:

[0107] P e -D X η e -P c =350-41.91×0.139-280=64.17MW;

[0108] At this time, the upper rotation reserve capacity of the coal-fired unit is 64.17MW.

[0109] Based on the above, it can be seen that the upward rotation reserve capacity of the coal-fired unit in this embodiment is 19.6MW.

[0110] Further, such as Figure 6 As shown, the present application also discloses a real-time calculation device for the rotational reserve capacity of a coal-fired unit, the device comprising:

[0111] A parameter acquisition module is used to acquire the equipment composition of the coal-fired unit and analyze the equipment type, operating parameters and design parameters of each equipment; the equipment type of the coal-fired unit includes key equipment and auxiliary equipment;

[0112] The defect analysis module is used to analyze whether the corresponding equipment has operating defects according to the equipment type of the coal-fired unit: when any key equipment has operating defects, the upper rotation reserve capacity of the coal-fired unit is 0; when only the auxiliary equipment has operating defects or no equipment has operating defects, proceed to the next step;

[0113] A constraint calculation module, used to calculate the first constraint, the second constraint and the third constraint according to the equipment parameters; wherein the first constraint includes the unit output constraint; the second constraint includes the powder making system output constraint, the fan output constraint and the environmental protection constraint; the third constraint includes the output constraint caused by the heating demand and the output constraint caused by the excessively high cold end parameters;

[0114] The capacity calculation module is used to analyze and obtain the spin-up reserve capacity of the coal-fired unit according to the first restricted constraint, the second restricted constraint and the third restricted constraint.

[0115] The device provided in the embodiment of the present application can achieve Figure 1 To avoid repetition, the various processes implemented by the method embodiment will not be described again here.

[0116] like Figure 7 As shown, the embodiment of the present application also provides an electronic device, including a processor and a memory, a program or instruction stored in the memory and executable on the processor, and when the program or instruction is executed by the processor, the following is achieved: Figure 1 The various processes of the method embodiment shown in the figure can achieve the same technical effect. To avoid repetition, they will not be described again here.

[0117] The embodiment of the present application also provides a readable storage medium on which a program or instruction is stored. When the program or instruction is executed by a processor, the above Figure 1 The various processes of the method embodiments described above can achieve the same technical effect, and will not be described again here to avoid repetition.

[0118] The present application also provides a computer program product, including computer instructions, which, when executed by a processor, implement the above Figure 1 The various processes of the method embodiments described above can achieve the same technical effect, and will not be described again here to avoid repetition.

[0119] It should be understood that "one embodiment" or "an embodiment" mentioned throughout the specification means that specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in various embodiments of the present application, the size of the sequence number of the above-mentioned processes does not mean the order of execution, and 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 application. The above-mentioned sequence numbers of the embodiments of the present application are only for description and do not represent the advantages and disadvantages of the embodiments.

[0120] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0121] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or components can be combined, or can be integrated into another device, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0122] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units; they may be located in one place or distributed on multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0123] In addition, all functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may be a separate unit, or two or more units may be integrated into one unit; the above-mentioned integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0124] A person skilled in the art can understand that all or part of the steps of implementing the above method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiment; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM), magnetic disks or optical disks, etc., various media that can store program codes.

[0125] Alternatively, if the above-mentioned integrated unit of the present application is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application can essentially or in other words, the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a device (which can be a terminal or a platform, etc.) to execute all or part of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0126] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A real-time calculation method for the spin-up reserve capacity of a coal-fired unit, characterized in that: The steps include: Obtaining the equipment composition of the coal-fired unit and analyzing the equipment type and equipment parameters of each equipment; the equipment type of the coal-fired unit includes key equipment and auxiliary equipment; Analyze whether the corresponding equipment has operating defects according to the equipment type of the coal-fired unit: when any key equipment has operating defects, the upper rotation reserve capacity of the coal-fired unit is 0; When only the auxiliary equipment has an operating defect or no equipment has an operating defect, proceed to the next step; The first restricted constraint, the second restricted constraint and the third restricted constraint are calculated and obtained according to the equipment parameters; wherein the first restricted constraint includes the output restriction of the unit; the second restricted constraint includes the output restriction of the pulverizing system, the output restriction of the fan and the environmental protection restriction; the third restricted constraint includes the output restriction caused by the heating demand and the output restriction caused by the excessively high cold end parameters; The spin-up reserve capacity of the coal-fired unit is obtained by analysis based on the first restricted constraint, the second restricted constraint and the third restricted constraint.

2. The real-time calculation method according to claim 1, characterized in that: The step of calculating and obtaining the first restricted constraint according to the device parameters comprises: Obtain the operating defects of each device in the fuel-fired unit and the load status of the unit; When there are no defects in the equipment of the coal-fired unit or only the auxiliary equipment has defects, determine whether the coal-fired unit is in a variable load state; When the coal-fired unit is not in a variable load state, the unit output limitation is calculated based on the rated power and current operating power of the coal-fired unit; When the coal-fired unit is in a variable load state, the unit output limitation is calculated based on the variable load rate setting value and the variable load time of the coal-fired unit at different times; The first restricted constraint is obtained according to the limited output calculation of the unit.

3. The real-time calculation method according to claim 2, characterized in that: The step of calculating and obtaining the first restricted constraint according to the limited output of the unit comprises: Obtain the output limitation of coal-fired units in variable load state or not in variable load state; Based on the upper spin reserve capacity P of coal-fired units U,T Must be less than or equal to the unit output limit P 机组 , obtain the first restricted constraint A1 of the coal-fired unit, that is, A1≤P 机组 .

4. The real-time calculation method according to claim 1, characterized in that: The step of calculating and obtaining the second restricted constraint according to the device parameters comprises: Obtaining equipment parameters of a pulverizing system, a fan, and a desulfurization system in a coal-fired unit; wherein the equipment parameters include at least the actual coal feed rate of the pulverizing system, the maximum operating coal feed rate of the pulverizing system, the maximum designed total air volume of the fan, the actual air volume of the fan, and the maximum sulfur dioxide flow rate allowed by the desulfurization system; The output limitation of the pulverizing system is calculated based on the maximum operating coal supply of the pulverizing system and the current actual coal supply; The fan output limitation is calculated based on the maximum designed total air volume of the fan and the current actual air volume; The environmental protection limit is calculated based on the maximum sulfur dioxide flow allowed by the desulfurization system and the sulfur content in the medium test results; The second constraint is obtained according to the limited output of the powder making system, the limited output of the fan and the limited environmental protection.

5. The real-time calculation method according to claim 4, characterized in that: The step of obtaining the second constraint according to the limited output of the milling system, the limited output of the fan and the limited environmental protection comprises: Obtain the results of the output limitation of the pulverizing system, the output limitation of the fan and the environmental protection limitation in the coal-fired unit; The minimum value function is used to calculate the output limitation of the pulverizing system, the fan output limitation and the environmental protection limitation to obtain the output limitation of the boiler system P 锅炉 ; Based on the upper spin reserve capacity P of coal-fired units U,T Must be less than or equal to the boiler system output limit P 锅炉 , and obtain the second restricted constraint A2 of the coal-fired unit, that is, A2≤P 锅炉 .

6. The real-time calculation method according to claim 1, characterized in that: The step of calculating and obtaining the third restricted constraint according to the device parameters comprises: Obtaining equipment parameters of a steam turbine in a coal-fired unit; wherein the equipment parameters of the steam turbine at least include heat extraction steam flow, ambient temperature, and turbine work efficiency coefficient under rated conditions, low-pressure cylinder steam work coefficient, and main steam operating conditions; wherein the main steam operating conditions at least include main steam temperature, main steam flow, and main steam pressure; The output limitation caused by the heating demand is calculated based on the heating extraction steam flow rate of the steam turbine, the steam work coefficient of the low-pressure cylinder and the current operating power; The output limitation due to excessively high cold end parameters is calculated based on the turbine work efficiency coefficient, main steam operating conditions and current operating power of the steam turbine; The third limiting constraint is obtained according to the output limitation caused by the heating demand and the output limitation caused by the excessively high cold end parameters.

7. The real-time calculation method according to claim 6, characterized in that: The step of obtaining the third limiting constraint according to the output limitation caused by the heating demand and the output limitation caused by the excessively high cold end parameters comprises: Obtain the results of output limitation caused by heating demand and output limitation caused by excessive cold end parameters in coal-fired units; The output limitation caused by the heating demand and the output limitation caused by the excessive cold end parameters are calculated using the minimum function to obtain the turbine output limitation P. 汽轮机 ; Based on the upper spin reserve capacity P of coal-fired units U,T Must be less than or equal to the turbine output limit P 汽轮机 , and obtain the third restricted constraint A3 of the coal-fired unit, that is, A3≤P 汽轮机 .

8. The real-time calculation method according to claim 1, characterized in that: The step of analyzing and obtaining the spin-up reserve capacity of the coal-fired unit according to the first restricted constraint, the second restricted constraint and the third restricted constraint comprises: Obtaining the first restricted constraint, the second restricted constraint and the third restricted constraint results of the coal-fired unit; Calculate the spin-up reserve capacity of coal-fired units based on the minimum function: <h2 style=";text-align:left;direction:ltr">P<h2 style=";text-align:left;direction:ltr"> U,T <h2 style=";text-align:left;direction:ltr"> (min(A1,A2,A3)) Where P U,T is the spin-up reserve capacity of the coal-fired unit; A1 is the first restricted constraint result of the coal-fired unit; A2 is the second restricted constraint result of the coal-fired unit; A3 is the third restricted constraint result of the coal-fired unit.

9. A real-time calculation device for the rotational reserve capacity of a coal-fired unit, characterized in that: The device comprises: A parameter acquisition module is used to acquire the equipment composition of the coal-fired unit and analyze the equipment type, operating parameters and design parameters of each equipment; the equipment type of the coal-fired unit includes key equipment and auxiliary equipment; The defect analysis module is used to analyze whether the corresponding equipment has operating defects according to the equipment type of the coal-fired unit: when any key equipment has operating defects, the upper rotation reserve capacity of the coal-fired unit is 0; when only the auxiliary equipment has operating defects or no equipment has operating defects, proceed to the next step; A constraint calculation module, used to calculate the first constraint, the second constraint and the third constraint according to the equipment parameters; wherein the first constraint includes the unit output constraint; the second constraint includes the powder making system output constraint, the fan output constraint and the environmental protection constraint; the third constraint includes the output constraint caused by the heating demand and the output constraint caused by the excessively high cold end parameters; The capacity calculation module is used to analyze and obtain the spin-up reserve capacity of the coal-fired unit according to the first restricted constraint, the second restricted constraint and the third restricted constraint.

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