A method, system, device and medium for real-time optimization of cold end system of thermal power unit

Abstract

The present invention relates to the technical field of condenser cold end, and in particular to a method, system, equipment and medium for real-time optimization of the cold end system of a thermal power unit, including: obtaining the real-time heat transfer coefficient of the condenser according to the collected real-time operation data of the unit; presetting the back pressure optimization parameters of the condenser, and obtaining the optimized flow rate of circulating water under the back pressure optimization parameters according to the real-time heat transfer coefficient of the condenser; obtaining the net power increment of the unit according to the optimized flow rate of circulating water and the back pressure optimization parameters, and judging whether the net power increment of the unit meets the preset conditions to determine the optimal parameters. The present invention solves the problem that the existing offline optimization method for the cold end of the thermal power unit cannot achieve accurate and real-time cold end optimization and the optimization algorithm is complex by performing online cold end optimization on the real-time status of the unit, and realizes online high-precision and low-latency cold end optimization, reduces the dependence on experimental data, and is suitable for popularization and use.

Description

Technical Field

[0001] The present invention relates to the technical field of condenser cold end, and in particular to a real-time optimization method, system, equipment and medium for a cold end system of a thermal power unit. Background Art

[0002] Limited by my country's energy resource endowment of "rich in coal, poor in oil, and little gas", coal-fired power generation has always been the main body of my country's electricity production. Improving the efficiency of conventional thermal power units is an effective technical measure to achieve the national "energy conservation and emission reduction" goal. Existing coal-fired power units achieve this goal by implementing coal-saving and consumption-reducing transformation, heating transformation and flexibility transformation. The coal-saving and consumption-reducing transformation of coal-fired power units is to improve the efficiency of the unit. From a thermodynamic perspective, the methods to achieve this goal include: improving the initial parameters of hot-end steam, reducing irreversible heat losses in the thermal system, and reducing the final parameters of cold-end steam. Among them, increasing the temperature and pressure of hot-end steam is a very effective means to improve the efficiency of the unit. However, the increase in hot-end parameters not only makes the system of the unit complex, but is also limited by high-temperature and high-pressure resistant steel technology. Under the limitations of current materials and equipment manufacturing processes, increasing the initial parameters of hot-end steam will significantly increase the investment cost of the unit.

[0003] The cold end system of a thermal power plant includes condensers, circulating water pumps, cooling towers, exhaust systems, rubber ball cleaning systems, etc. The optimization of the cold end system is based on comprehensive consideration of the low-pressure cylinder of the turbine, condenser, circulating water system, condensate system, exhaust equipment and all parameters related to operating costs to determine the optimal values ​​of various operating parameters corresponding to the optimal condenser vacuum. The efficiency of the unit cold end system is mainly reflected in the condenser vacuum. For a subcritical 300MW unit, a vacuum of 1kPa affects the unit output by about 1%. Therefore, compared with the high difficulty and high investment in improving the hot end parameters, strengthening the energy-saving optimization and transformation of the cold end system and equipment characteristics of thermal power units can reduce Low unit back pressure has great practical significance for power plants to achieve energy conservation and consumption reduction and improve economic benefits. At present, reducing unit back pressure is mainly achieved by increasing the circulating cooling medium flow rate of the condenser, reducing the circulating cooling medium temperature, or enhancing the heat exchange capacity of the condenser. Among them, changing the circulating cooling medium flow rate can be achieved by changing the operating mode of the circulating water pump or the frequency conversion of the circulating water pump; the reduction of the circulating cooling medium temperature is mainly related to the ambient temperature and the cooling method, and the cooling tower needs to be modified when necessary; enhancing the heat exchange capacity of the condenser is mainly to reduce condenser scaling, improve the cleanliness of the condenser, or modify the condenser tube bundle structure.

[0004] The cold end optimization of thermal power units is to reduce the back pressure of the units, so that the power generation of the units increases at the same main steam flow rate; if the power generation remains unchanged, the main steam volume of the units is reduced, and the fuel consumption is also reduced, achieving the goal of energy saving and consumption reduction. For the cold end optimization scheme of changing the circulating water flow rate, when the circulating water flow rate increases, the back pressure of the units decreases, the power generation increases, but the power consumption of the circulating water pump also increases accordingly. When the increment of the power generation of the units is the same as the increment of the power consumption of the circulating water pump, the energy saving effect of the cold end optimization is not reflected. Therefore, it is necessary to find the back pressure and circulating water flow rate when the net increment of the unit power is the largest, so as to achieve the goal of cold end optimization energy saving and consumption reduction.

[0005] The current cold-end optimization method for adjusting the circulating water flow rate is mainly to establish the functional relationship between the unit's power generation power and the circulating water flow rate, and the functional relationship between the circulating water pump power and the circulating water flow rate, and then solve the equation or other optimization methods to obtain the cooling medium flow rate and unit back pressure with the largest net power increase of the unit. The function establishment process of this scheme is complicated and requires a lot of test data support, and the function solution or optimization algorithm is relatively complex. Generally, a large number of functions are established under different boundary parameter conditions for optimization and solution. The optimal circulation pump operation mode and unit back pressure within a certain range obtained by offline calculation are used to provide guidance for the operation of the unit. Therefore, it is impossible to achieve accurate and real-time cold-end optimization, and the long-term operation equipment performance of the unit will gradually deviate from the test conditions, the optimization results will deviate from the actual, the optimization effect will deteriorate, and the optimization results will no longer be applicable to the current equipment operation status. Summary of the invention

[0006] The present invention provides a method, system, device and medium for real-time optimization of the cold end system of a thermal power unit, and solves the technical problem that the existing cold end offline optimization method of a thermal power unit cannot achieve accurate and real-time cold end optimization, and the optimization algorithm is complex, which not only leads to the gradual deviation of the equipment performance from the operating conditions during the test during the long-term operation of the unit, resulting in poor optimization effect, but also makes it difficult to achieve low-latency and high-precision optimization calculation problems in the DCS system of the unit.

[0007] In order to solve the above technical problems, the present invention provides a method, system, equipment and medium for real-time optimization of the cold end system of a thermal power unit.

[0008] In a first aspect, the present invention provides a method for real-time optimization of a cold end system of a thermal power unit, the method comprising the following steps:

[0009] According to the collected real-time operation data of the unit, the real-time heat transfer coefficient of the condenser is obtained;

[0010] Presetting the back pressure optimization parameters of the condenser, and obtaining the optimal flow rate of circulating water under the back pressure optimization parameters according to the real-time heat transfer coefficient of the condenser;

[0011] Calculate the power increment of the circulating water pump according to the optimized circulating water flow rate;

[0012] Obtaining a generator power increment according to the back pressure optimization parameter and the collected real-time generator power;

[0013] Obtaining a net power increment of the unit according to the power increment of the circulating water pump and the power increment of the generator;

[0014] Determine whether the net power increase of the unit meets the preset conditions. If not, reset the back pressure optimization parameters of the condenser and repeat the above steps. If yes, use the back pressure optimization parameters and circulating water optimization flow corresponding to the preset conditions as the optimal parameters.

[0015] In a further embodiment, the real-time operation data of the unit includes the real-time back pressure of the condenser, the real-time inlet and outlet temperatures of the first circulating water, the real-time flow rate of the circulating water, the real-time power of the circulating water pump and the real-time power generation power of the generator.

[0016] In a further embodiment, the calculation formula of the real-time heat transfer coefficient of the condenser is:

[0017]

[0018] In the formula, K c Indicates the real-time heat transfer coefficient of the condenser, D w Indicates the real-time flow rate of circulating water, c w Indicates the real-time specific heat capacity of circulating water, A c It represents the real-time heat transfer area of ​​the condenser tube bundle, Δt represents the real-time temperature rise of the circulating water, and δt represents the real-time end difference of the condenser.

[0019] In a further embodiment, the step of obtaining the optimized flow rate of circulating water under the back pressure optimization parameters according to the real-time heat transfer coefficient of the condenser comprises:

[0020] According to the back pressure optimization parameter, the exhaust steam condensation optimization temperature is obtained;

[0021] The real-time heat transfer coefficient of the condenser and the real-time end difference of the condenser are used as the optimized heat transfer coefficient of the condenser and the optimized end difference of the condenser respectively;

[0022] According to the exhaust steam condensation optimization temperature, the condenser optimization end difference and the collected second circulating water inlet real-time temperature, the circulating water optimization temperature rise is obtained;

[0023] The optimal flow rate of circulating water under the back pressure optimization parameters is calculated based on the optimized heat transfer coefficient of the condenser and the optimized temperature rise of the circulating water.

[0024] In a further embodiment, the step of calculating the circulating water pump power increment according to the circulating water optimized flow rate comprises:

[0025] According to the optimized circulating water flow and the pre-established circulating water pump power model, the optimized power of the circulating water pump is obtained;

[0026] A circulating water pump power increment is obtained according to the circulating water pump optimized power and the circulating water pump real-time power.

[0027] In a further embodiment, the preset condition includes the net increase in power of the unit being a maximum value.

[0028] In a further embodiment, the method further comprises: presetting an optimization time interval, and optimizing the cold end system of the thermal power unit according to the optimization time interval.

[0029] In a second aspect, the present invention provides a real-time optimization system for a cold end system of a thermal power unit, the system comprising:

[0030] The heat transfer coefficient calculation module is used to obtain the real-time heat transfer coefficient of the condenser based on the collected real-time operation data of the unit;

[0031] A circulating water flow calculation module, used to preset the back pressure optimization parameters of the condenser, and obtain the circulating water optimization flow under the back pressure optimization parameters according to the real-time heat transfer coefficient of the condenser;

[0032] The unit power net increment acquisition module is used to calculate the circulating water pump power increment according to the circulating water optimization flow rate; it is also used to obtain the generator power increment according to the back pressure optimization parameter and the collected real-time generator power, and obtain the unit power net increment according to the circulating water pump power increment and the generator power increment;

[0033] The optimal parameter determination module is used to determine whether the net increase in unit power meets the preset conditions. If not, the back pressure optimization parameters of the condenser are reset and the above steps are repeated; if so, the back pressure optimization parameters and circulating water optimization flow corresponding to the preset conditions are used as the optimal parameters.

[0034] In a third aspect, the present invention further provides a computer device, comprising a processor and a memory, wherein the processor is connected to the memory, the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory so that the computer device performs the steps of implementing the above method.

[0035] In a fourth aspect, the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program implements the steps of the above method when executed by a processor.

[0036] The present invention provides a method, system, device and medium for real-time optimization of the cold end system of a thermal power unit. The method models and analyzes the heat exchange process of the condenser to obtain a simplified calculation formula for the heat transfer coefficient that characterizes the heat transfer performance of the condenser, and establishes a circulating water flow calculation model based on this. The functional relationship between the circulating water flow and the power consumption of the circulating water pump and the functional relationship between the unit power and the back pressure is combined to achieve a high-precision, real-time online cold end optimization technical solution. Compared with the prior art, the method realizes online high-precision, low-latency cold end optimization for the problem that the equipment performance gradually deviates from the operating conditions during the test during the long-term operation of the unit, which has a very positive significance for the long-term operation design optimization and practical development of thermal power units. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic flow chart of a method for real-time optimization of a cold end system of a thermal power unit provided by an embodiment of the present invention;

[0038] Figure 2 It is a schematic diagram of the changes of circulating water temperature and steam temperature in the condenser provided by an embodiment of the present invention;

[0039] Figure 3 This is a block diagram of a real-time optimization system for a cold end system of a thermal power unit provided by an embodiment of the present invention;

[0040] Figure 4 It is a schematic diagram of the structure of a computer device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following specifically illustrates the implementation mode of the present invention in conjunction with the accompanying drawings. The embodiments are provided for illustrative purposes only and cannot be understood as limiting the present invention. The accompanying drawings are provided for reference and illustration only and do not constitute a limitation on the scope of patent protection of the present invention, because many changes can be made to the present invention without departing from the spirit and scope of the present invention.

[0042] refer to Figure 1 The embodiment of the present invention provides a method for real-time optimization of the cold end system of a thermal power unit, such as Figure 1 As shown, the method comprises the following steps:

[0043] S1. According to the collected real-time operation data of the unit, the real-time heat transfer coefficient of the condenser is obtained; wherein the real-time operation data of the unit includes the following data: real-time back pressure p of the condenser, real-time temperature t of the first circulating water inlet w1 , the real-time temperature of the first circulating water outlet tw2 , circulating water real-time flow D w , circulating water pump real-time power W p And the real-time power generation E of the generator P .

[0044] The cold end system is an important auxiliary system of thermal power units. The quality of its operation directly affects the operating economy, safety and reliability of the unit. Therefore, studying the cold end system, improving its working performance and achieving optimal operation of the cold end system are important means for power stations to reduce production costs and improve the thermal economy of the unit. Among them, the cold end system of a thermal power unit mainly includes the final stage of the low-pressure cylinder, the condenser, the circulating water cooling device, and the circulating water pump; among them, the most important equipment in the cold end system of a thermal power unit is the condenser. The heat exchange process of the condenser is that the exhaust steam of the low-pressure cylinder enters the condenser and exchanges heat with the circulating water through the heat exchange tube bundle and is condensed into condensed water. Since the condensation process of the exhaust steam is a constant temperature and pressure process, the exhaust steam condensation temperature remains unchanged; the circulating water absorbs the latent heat of vaporization during the condensation process of the steam, and the temperature rises; in the heat exchange process of the condenser, with the change of the heat exchange tube, the changes in the circulating water temperature and the exhaust steam temperature are as follows: Figure 2 As shown, in Figure 2 In the figure, Δt represents the real-time temperature rise of circulating water, and δt represents the real-time terminal difference of condenser.

[0045] In this embodiment, the calculation formula of the real-time heat transfer coefficient of the condenser is:

[0046]

[0047] In the formula, K c Indicates the real-time heat transfer coefficient of the condenser, D w Indicates the real-time flow rate of circulating water, c w Indicates the real-time specific heat capacity of circulating water, A c It represents the real-time heat transfer area of ​​the condenser tube bundle, Δt represents the real-time temperature rise of the circulating water, and δt represents the real-time end difference of the condenser.

[0048] In order to facilitate the understanding of the calculation formula of the real-time heat transfer coefficient of the condenser, the derivation process of the heat transfer coefficient calculation formula will be specifically described below:

[0049] The real-time exhaust condensation temperature is calculated based on the real-time operation data of the unit, and the calculation formula is:

[0050] t s =t w1 +Δt+δt

[0051] Where, t s Indicates the real-time temperature of exhaust steam condensation (steam temperature), t w1 represents the real-time temperature of the first circulating water inlet, Δt represents the real-time temperature rise of the circulating water, and δt represents the real-time end difference of the condenser, where Δt = tw2 -t w1 ,δt=t s -t w2 .

[0052] At the same time, the energy balance equation of the steam side and the water side of the condenser heat exchange process is:

[0053] D ex (h ex -h cw )=D w c w Δt

[0054] Where D ex Indicates the exhaust mass flow rate of low-pressure cylinder, h ex Indicates the exhaust enthalpy of the low-pressure cylinder, h cw Denotes the condensation enthalpy, D w Indicates the real-time flow rate of circulating water, c w Indicates the real-time specific heat capacity of circulating water.

[0055] Since the heat transfer principle of the condenser conforms to the heat transfer process, the heat transfer equations of the steam side and the water side through the condenser during the condenser heat transfer process at the current moment are:

[0056] Φ c =K c *A c *Δt m

[0057] In the formula, Φ c Indicates the heat transfer of the steam side and the water side through the condenser during the condenser heat transfer process, K c Indicates the real-time heat transfer coefficient of the condenser, A c Indicates the real-time heat transfer area of ​​the condenser tube bundle, Δt m Represents the logarithmic mean temperature difference between the cold and hot fluids in the condenser.

[0058] The logarithmic mean temperature difference Δt of the hot and cold fluids in the condenser m The calculation equation is:

[0059]

[0060] According to the second law of thermodynamics, the heat released by the steam side, the heat absorbed by the water side, and the heat transferred by the condenser are equal. Therefore, the energy balance equation between the steam side and the water side in the condenser heat exchange process is equal to the heat transfer equation between the steam side and the water side through the condenser in the condenser heat transfer process. Combining the above formulas, the following equation can be obtained:

[0061]

[0062] The heat transfer coefficient K of the condenser can be further obtained from the above formula:c and circulating water flow D w The calculation formula is as follows:

[0063]

[0064]

[0065] S2. Preset the back pressure optimization parameters of the condenser, and obtain the optimal flow rate of circulating water under the back pressure optimization parameters according to the real-time heat transfer coefficient of the condenser.

[0066] In one embodiment, the step of obtaining the optimal flow rate of circulating water under the back pressure optimization parameter according to the real-time heat transfer coefficient of the condenser includes:

[0067] According to the back pressure optimization parameter, the exhaust steam condensation optimization temperature is obtained;

[0068] The real-time heat transfer coefficient of the condenser and the real-time end difference of the condenser are used as the optimized heat transfer coefficient of the condenser and the optimized end difference of the condenser respectively;

[0069] According to the exhaust steam condensation optimization temperature, the condenser optimization end difference and the collected second circulating water inlet real-time temperature, the circulating water optimization temperature rise is obtained;

[0070] The optimal flow rate of circulating water under the back pressure optimization parameters is calculated based on the optimized heat transfer coefficient of the condenser and the optimized temperature rise of the circulating water.

[0071] Specifically, this embodiment assumes that the optimized condenser back pressure (back pressure optimization parameter) is p′, and obtains the corresponding exhaust condensation optimization temperature t according to the water and steam property query function. s ′, since the back pressure of the condenser changes faster than the ambient temperature, and the heat transfer performance of the condenser is its inherent characteristic and will not change due to scaling and other reasons in a short period of time, for the primary cold end optimization process being calculated, it is assumed that the condenser optimization heat transfer coefficient K corresponding to the back pressure optimization parameter p′ c ' is the real-time heat transfer coefficient K of the condenser calculated in step S1 above c , the condenser optimized end difference δt′ is the condenser real-time end difference δt calculated in the above step S1, that is, K c ′=K c , δt′=δt, according to the real-time measured second circulating water inlet real-time temperature t w1 ′, and the optimal temperature rise of circulating water Δt′ is calculated. The calculation formula of the optimal temperature rise of circulating water is:

[0072] Δt′=t s ′-δt′-t w1 '

[0073] Therefore, the optimal flow rate of circulating water under the back pressure optimization parameter can be calculated according to the optimized heat transfer coefficient of the condenser and the optimized temperature rise of the circulating water. The specific calculation formula is:

[0074]

[0075] Where D w ′ represents the optimized flow rate of circulating water.

[0076] Compared with the prior art, this embodiment uses the real-time heat transfer coefficient of the condenser to obtain the optimized flow rate of circulating water under the back pressure optimization parameters, thereby increasing the utilization of the unit operation data and reducing the dependence on test data.

[0077] S3. Calculate the circulating water pump power increment based on the optimized circulating water flow rate.

[0078] In one embodiment, the step of calculating the circulating water pump power increment according to the circulating water optimized flow rate comprises:

[0079] A circulating water pump power model is constructed according to the historical circulating water pump power and the historical circulating water flow rate. In this embodiment, the circulating water pump power model represents the functional relationship between the circulating water pump power and the circulating water flow rate;

[0080] Inputting the optimized flow rate of circulating water under the back pressure optimization parameter into a pre-established circulating water pump power model to obtain the corresponding optimized power of the circulating water pump;

[0081] The circulating water pump optimizes the power W p ' and the real-time power W of the circulating water pump p Difference, get the circulating water pump power increment ΔW p , the specific formula is: ΔW p =W p ′-W p .

[0082] S4. Obtaining the generator power increment according to the back pressure optimization parameter and the real-time power generated by the generator collected, this step specifically includes:

[0083] A generator power generation model is constructed according to the historical generator power generation of the unit and the historical condenser back pressure of the unit. In this embodiment, the generator power generation model represents the functional relationship between the generator power generation of the unit and the condenser back pressure of the unit;

[0084] Inputting the back pressure optimization parameter into a pre-established generator power generation model to obtain the corresponding generator optimized power generation;

[0085] The generator optimizes the power generation Ep ' and the real-time power generation E of the generator P The difference is calculated to obtain the generator power increment ΔE, wherein the calculation formula for the generator power increment is:

[0086] ΔE=E P ′-E P

[0087] S5. According to the circulating water pump power increment ΔW p and the generator power increment ΔE, the net power increment ΔQ of the unit is obtained, wherein the calculation formula of the net power increment of the unit is:

[0088] ΔQ=ΔE-ΔW p

[0089] S6. Determine whether the net power increase of the unit meets the preset conditions. If not, reset the back pressure optimization parameters of the condenser and repeat the above steps. If so, use the back pressure optimization parameters and circulating water optimization flow corresponding to the preset conditions as the optimal parameters. Among them, this embodiment determines the circulating water pump operation mode corresponding to the optimal parameters as the optimal circulating water pump operation mode, and provides the optimal circulating water pump operation mode to the power plant operation personnel.

[0090] In one embodiment, the preset condition includes that the net power increase of the unit is maximum.

[0091] This embodiment first determines whether the net power increment of the unit is the maximum value. If so, the back pressure optimization parameters corresponding to the maximum value of the net power increment of the unit, the optimized flow rate of circulating water, and the corresponding operating mode and energy saving of the circulating water pump are used as optimal parameters, and the optimal parameters are provided to the power plant operation personnel, thereby providing more direct reference information for the power plant operation personnel to correctly make operation or maintenance measures; if not, repeat the above steps S2 to S5 to traverse and optimize until the maximum value of the net power increment of the unit is found.

[0092] In one embodiment, a real-time optimization method for a cold end system of a thermal power unit provided in this embodiment further includes: presetting an optimization time interval, and executing the above steps S1 to S6 according to the optimization time interval to optimize the cold end system of the thermal power unit.

[0093] It should be noted that in order to avoid frequent cold-end optimization results from complicating the operation of the circulating water pump, the optimization time interval can be set according to the actual implementation situation, and the above steps S1 to S6 can be performed regularly, so as to achieve high-precision, low-latency and highly adaptable cold-end system optimization of the thermal power unit.

[0094] The embodiment of the present invention provides a real-time optimization method for the cold end system of a thermal power unit. The method analyzes the heat exchange process of the condenser and based on the heat transfer coefficient calculation equation of the condenser, realizes the optimized operation of the cold end system, determines the optimal operation mode of the circulating water pump, and improves the unit economy. Compared with the prior art, the cold end system optimization method adopted in this embodiment can not only realize the cold end optimization of the thermal power unit with high precision, low delay and strong adaptability, but also reduce the dependence on test data, simplify the function equation group and optimization process of the cold end optimization, and has great practical significance for power plants to achieve energy saving and consumption reduction and improve thermal economic benefits.

[0095] It should be noted that the size of the serial numbers of the above-mentioned processes does not mean 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 application.

[0096] In one embodiment, Figure 3 As shown, an embodiment of the present invention provides a real-time optimization system for a cold end system of a thermal power unit, the system comprising:

[0097] The heat transfer coefficient calculation module 101 is used to obtain the real-time heat transfer coefficient of the condenser according to the collected real-time operation data of the unit;

[0098] The circulating water flow calculation module 102 is used to preset the back pressure optimization parameters of the condenser and obtain the circulating water optimization flow under the back pressure optimization parameters according to the real-time heat transfer coefficient of the condenser;

[0099] The unit power net increment acquisition module 103 is used to calculate the circulating water pump power increment according to the circulating water optimization flow rate; it is also used to obtain the generator power increment according to the back pressure optimization parameter and the collected real-time generator power, and obtain the unit power net increment according to the circulating water pump power increment and the generator power increment;

[0100] The optimal parameter determination module 104 is used to determine whether the net increase in unit power meets the preset conditions. If not, the back pressure optimization parameters of the condenser are reset and the above steps are repeated; if so, the back pressure optimization parameters and circulating water optimization flow corresponding to the preset conditions are used as the optimal parameters.

[0101] For the specific definition of a real-time optimization system for the cold end system of a thermal power unit, please refer to the above-mentioned definition of a real-time optimization method for the cold end system of a thermal power unit, which will not be repeated here. A person of ordinary skill in the art can appreciate that the various modules and steps described in conjunction with the embodiments disclosed in this application can be implemented in hardware, software, or a combination of both. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0102] The embodiment of the present invention provides a real-time optimization system for the cold end system of a thermal power unit. The heat transfer coefficient calculation module analyzes the heat exchange process of the condenser. At the same time, the circulating water flow calculation module obtains the optimized circulating water flow under the optimized back pressure parameter based on the heat transfer coefficient of the condenser. The unit power net increment acquisition module and the optimal parameter determination module combine the functional relationship between the circulating water flow and the power consumption of the circulating water pump and the functional relationship between the unit power and the back pressure to realize a high-precision online cold end optimization method. Compared with the prior art, the present application realizes online cold end optimization based on the heat transfer coefficient calculation equation of the condenser, and can optimize and adjust the cold end system as the operating conditions of the thermal power unit equipment change, thereby improving the safety and reliability of the cold end system of the thermal power unit.

[0103] Figure 4 A computer device provided by an embodiment of the present invention includes a memory, a processor and a transceiver, which are connected via a bus; the memory is used to store a set of computer program instructions and data, and can transmit the stored data to the processor, and the processor can execute the program instructions stored in the memory to perform the steps of the above method.

[0104] The memory may include a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories; the processor may be a central processing unit, a microprocessor, an application-specific integrated circuit, a programmable logic device, or a combination thereof. By way of example but not limitation, the programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic, or any combination thereof.

[0105] Additionally, the memory may be a physically separate unit or may be integrated with the processor.

[0106] It can be understood by those skilled in the art that Figure 4 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have the same component arrangement.

[0107] In one embodiment, the present invention provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the above method are implemented.

[0108] The embodiment of the present invention provides a method, system, device and medium for real-time optimization of the cold end system of a thermal power unit. The method reduces the difficulty of solving functions and simplifies the cold end optimization process by calculating the heat transfer performance and circulating water flow rate of a condenser. At the same time, the embodiment is based on the heat transfer coefficient calculation equation of the condenser, makes full use of the real-time operation data of the unit, mines historical data, reduces the dependence on test data, reduces the workload of cold end optimization data preparation, solves the current cold end optimization needs a lot of test data support, and the optimization result has a large deviation after the unit has been in operation for a long time and the health status of the equipment has changed, and the calculation function and equation involved in the current cold end optimization technology are difficult to solve, the optimization algorithm is complex, and it is difficult to achieve low-latency and high-precision optimization calculation in the DCS system of the unit. The technical solution for online, high-precision and low-latency cold end optimization of the real-time state of the thermal power unit is realized, and the problem that the optimization result of the traditional cold end system offline optimization method is no longer applicable due to the deviation of the equipment operation state from the test state during the long-term operation of the unit is avoided.

[0109] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., an SSD), etc.

[0110] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing related hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods.

[0111] The above-mentioned embodiments only express several preferred implementation modes of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in the technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be regarded as the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be based on the protection scope of the claims.

Claims

1. A real-time optimization method for the cold end system of a thermal power unit, characterized in that: The following steps are involved: According to the collected real-time operation data of the unit, the real-time heat transfer coefficient of the condenser is obtained; Presetting the back pressure optimization parameters of the condenser, and obtaining the optimal flow rate of circulating water under the back pressure optimization parameters according to the real-time heat transfer coefficient of the condenser; Calculate the power increment of the circulating water pump according to the optimized circulating water flow rate; Obtaining a generator power increment according to the back pressure optimization parameter and the collected real-time generator power; Obtaining a net power increment of the unit according to the power increment of the circulating water pump and the power increment of the generator; Determine whether the net power increment of the unit meets the preset conditions. If not, reset the back pressure optimization parameters of the condenser and repeat the above steps. If yes, use the back pressure optimization parameters and circulating water optimization flow rate corresponding to the preset conditions as the optimal parameters. The preset conditions include that the net power increment of the unit is the maximum value. Wherein, the calculation formula of the real-time heat transfer coefficient of the condenser is: In the formula, represents the real-time heat transfer coefficient of the condenser, Indicates the real-time flow of circulating water. Indicates the real-time specific heat capacity of circulating water, Indicates the real-time heat transfer area of ​​the condenser tube bundle, Indicates the real-time temperature rise of circulating water. Indicates the real-time terminal difference of the condenser.

2. A method for real-time optimization of a cold end system of a thermal power unit according to claim 1, characterized in that: The real-time operation data of the unit include the real-time back pressure of the condenser, the real-time inlet and outlet temperatures of the first circulating water, the real-time flow rate of the circulating water, the real-time power of the circulating water pump and the real-time power generation power of the generator.

3. A method for real-time optimization of a cold-end system of a thermal power unit according to claim 1, characterized in that: The step of obtaining the optimal flow rate of circulating water under the back pressure optimization parameter according to the real-time heat transfer coefficient of the condenser comprises: According to the back pressure optimization parameter, the exhaust steam condensation optimization temperature is obtained; The real-time heat transfer coefficient of the condenser and the real-time end difference of the condenser are used as the optimized heat transfer coefficient of the condenser and the optimized end difference of the condenser respectively; According to the exhaust steam condensation optimization temperature, the condenser optimization end difference and the collected second circulating water inlet real-time temperature, the circulating water optimization temperature rise is obtained; The optimal flow rate of circulating water under the back pressure optimization parameters is calculated based on the optimized heat transfer coefficient of the condenser and the optimized temperature rise of the circulating water.

4. A method for real-time optimization of a cold end system of a thermal power unit according to claim 2, characterized in that: The step of calculating the circulating water pump power increment according to the circulating water optimized flow rate comprises: According to the optimized circulating water flow and the pre-established circulating water pump power model, the optimized power of the circulating water pump is obtained; A circulating water pump power increment is obtained according to the circulating water pump optimized power and the circulating water pump real-time power.

5. A method for real-time optimization of a cold-end system of a thermal power unit according to claim 1, characterized in that: The method further comprises: presetting an optimization time interval, and optimizing the cold end system of the thermal power unit according to the optimization time interval.

6. A real-time optimization system for the cold end system of a thermal power unit, characterized in that: The system comprises: The heat transfer coefficient calculation module is used to obtain the real-time heat transfer coefficient of the condenser based on the collected real-time operation data of the unit; A circulating water flow calculation module, used to preset the back pressure optimization parameters of the condenser, and obtain the circulating water optimization flow under the back pressure optimization parameters according to the real-time heat transfer coefficient of the condenser; The unit power net increment acquisition module is used to calculate the circulating water pump power increment according to the circulating water optimization flow rate; it is also used to obtain the generator power increment according to the back pressure optimization parameter and the collected real-time generator power, and obtain the unit power net increment according to the circulating water pump power increment and the generator power increment; The optimal parameter determination module is used to determine whether the net power increment of the unit meets the preset conditions. If not, the back pressure optimization parameters of the condenser are reset and the above steps are repeated; if yes, the back pressure optimization parameters and the circulating water optimization flow rate corresponding to the preset conditions are used as the optimal parameters; the preset conditions include that the net power increment of the unit is the maximum value; Wherein, the calculation formula of the real-time heat transfer coefficient of the condenser is: In the formula, represents the real-time heat transfer coefficient of the condenser, Indicates the real-time flow of circulating water. Indicates the real-time specific heat capacity of circulating water, Indicates the real-time heat transfer area of ​​the condenser tube bundle, Indicates the real-time temperature rise of circulating water. Indicates the real-time terminal difference of the condenser.

7. A computer device, characterized in that: The computer device comprises a processor and a memory, wherein the processor is connected to the memory, the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the computer device executes the method according to any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed, the method according to any one of claims 1 to 5 is implemented.

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