System and method for measuring exhaust enthalpy of low-pressure cylinder of steam turbine generator unit in real time

Abstract

The invention discloses a steam turbine generator unit low-pressure cylinder exhaust steam enthalpy real-time measuring system and method, and belongs to the technical field of thermal power generation, the system comprises a low-pressure cylinder, a condenser, a circulating water pump, a small condenser, a small condenser circulating water booster pump, a small condenser condensed water booster pump, a small condenser vacuumizing pump and a measuring device; the measuring device comprises a low-pressure cylinder steam exhaust pressure transmitter, a small condenser circulating water outlet ultrasonic flowmeter, a small condenser circulating water outlet temperature transmitter, a small condenser circulating water outlet pressure transmitter, a small condenser circulating water inlet pressure transmitter and a small condenser circulating water inlet temperature transmitter. A small condenser condensation water pressure transmitter, a small condenser condensation water temperature transmitter and a small condenser condensation water ultrasonic flowmeter. According to the invention, the problems of many measurement parameters, high cost and large measurement error in the prior art are solved.

Description

Technical Field

[0001] The present invention relates to a real-time measurement system and method for the exhaust enthalpy of the low-pressure cylinder of a steam turbine generator set, belonging to the technical field of thermal power generation. Background Art

[0002] In the field of thermal power generation, the exhaust enthalpy value of the low-pressure cylinder of a steam turbine has always been a key parameter for evaluating the thermal efficiency of the unit and has received much attention. With the continuous improvement of the requirements for efficient and energy-saving operation in the thermal power industry, accurately measuring the exhaust enthalpy value of the low-pressure cylinder has become a research hotspot. Traditionally, the measurement of the exhaust enthalpy of the low-pressure cylinder mainly relies on complex measurement systems and a large number of sensors. This method calculates the exhaust enthalpy value by measuring multiple parameters such as the temperature and pressure of the exhaust steam and combining steam thermodynamic property charts or empirical formulas. The principle of this measurement method is relatively straightforward and, to a certain extent, meets the basic requirements of the industry for the measurement of the exhaust enthalpy value. At the same time, with the continuous development of technology, some scholars have also proposed a measurement method based on neural networks, which uses the non-linear fitting ability of neural networks to learn and train a large amount of operating data to establish a more accurate calculation model for the exhaust enthalpy value.

[0003] However, the traditional methods for measuring the exhaust enthalpy of the low-pressure cylinder have many drawbacks. First, since the exhaust steam of the low-pressure cylinder is in a state of low temperature and pressure, the measurement process is easily interfered by environmental factors, and small temperature fluctuations or pressure changes may cause a significant increase in measurement errors. Second, the use of a large number of sensors not only increases the measurement cost but also improves the complexity of the system. There are also difficulties in calibrating and coordinating between sensors, further affecting the measurement accuracy. In addition, although the measurement method based on neural networks improves the measurement accuracy to a certain extent, it has extremely high requirements for the amount and quality of data. If the training data is insufficient or there are errors, the accuracy and generalization ability of the model will be greatly reduced. At the same time, the physical meaning of the neural network model is not clear, making it difficult to conduct in-depth explanations and optimizations from a theoretical level. Therefore, the existing technology is difficult to measure the exhaust enthalpy value of the low-pressure cylinder in real time and accurately, and cannot meet the needs of modern thermal power generator sets for efficient operation monitoring. Summary of the Invention

[0004] The purpose of the present invention is to provide a real-time measurement system and method for the exhaust enthalpy of the low-pressure cylinder of a steam turbine generator set. By extracting the exhaust steam of the low-pressure cylinder of the steam turbine from the exhaust steam pipeline and ingeniously introducing a small condenser and using the heat balance of the small condenser to calculate the exhaust enthalpy value of the low-pressure cylinder, the problems of many measurement parameters, high cost, and large measurement errors in the existing technology are solved. It realizes the use of fewer measurement parameters, effectively reduces the measurement error while reducing the measurement cost, and thus accurately and real-time measures the exhaust enthalpy value of the low-pressure cylinder.

[0005] To solve the above technical problems, the present invention is implemented by adopting the following technical solutions.

[0006] In a first aspect, the present invention provides a real-time measurement system for the exhaust enthalpy of a low-pressure cylinder of a steam turbine generator set, comprising:

[0007] A low-pressure cylinder (1), a condenser (2), a circulating water pump (3), a small condenser (4), a small condenser circulating water booster pump (5), a small condenser condensate booster pump (6), a small condenser vacuum pump (7), and a measuring device;

[0008] Among them, the exhaust steam of the low-pressure cylinder in the low-pressure cylinder exhaust steam pipeline is introduced into the small condenser (4). The small condenser circulating water booster pump (5) extracts circulating water from the outlet pipeline of the circulating water pump (3) to cool the exhaust steam of the low-pressure cylinder entering the small condenser (4). After heat exchange in the small condenser (4), the exhaust steam of the low-pressure cylinder condenses into water, which flows into the hot well of the condenser (2) after being boosted by the small condenser condensate booster pump (6). The small condenser vacuum pump (7) extracts the uncondensed gas in the small condenser (4) to keep the small condenser (4) at a low vacuum;

[0009] The measuring device includes:

[0010] A low-pressure cylinder exhaust steam pressure transmitter (8) installed on the low-pressure cylinder exhaust steam pipeline;

[0011] A small condenser circulating water outlet ultrasonic flowmeter (9), a small condenser circulating water outlet temperature transmitter (10), and a small condenser circulating water outlet pressure transmitter (11) respectively installed on the small condenser circulating water outlet pipeline;

[0012] A small condenser circulating water inlet pressure transmitter (12) and a small condenser circulating water inlet temperature transmitter (13) installed on the small condenser circulating water inlet pipeline;

[0013] A small condenser condensate pressure transmitter (14), a small condenser condensate temperature transmitter (15), and a small condenser condensate ultrasonic flowmeter (16) installed on the small condenser condensate pipeline.

[0014] Further, the low-pressure cylinder (1) generates exhaust steam;

[0015] The condenser (2) is used for condensing the steam of the conventional low-pressure cylinder exhaust;

[0016] The circulating water pump (3) is used to provide power for the flow of circulating water;

[0017] The small condenser (4) is used for condensing the steam extracted from the exhaust steam pipeline of the low-pressure cylinder (1);

[0018] The small condenser circulating water booster pump (5) is used to increase the pressure of the small condenser circulating water;

[0019] The condensate booster pump (6) of the small condenser is used to boost the pressure of the condensate in the hot well of the small condenser and send it to the hot well of the main condenser.

[0020] The vacuum pump (7) of the small condenser is used to extract the non-condensable gas in the small condenser (4).

[0021] Furthermore, the exhaust steam pressure transmitter (8) of the low-pressure cylinder is used to measure the exhaust steam pressure of the low-pressure cylinder in real time ;

[0022] The ultrasonic flowmeter (9) for the outlet of the circulating water of the small condenser, the temperature transmitter (10) for the outlet of the circulating water of the small condenser, and the pressure transmitter (11) for the outlet of the circulating water of the small condenser are used to monitor the flow rate , temperature and pressure ;

[0023] The pressure transmitter (12) for the inlet of the circulating water of the small condenser and the temperature transmitter (13) for the inlet of the circulating water of the small condenser are used to measure the pressure and temperature ;

[0024] The condensate pressure transmitter (14) of the small condenser, the condensate temperature transmitter (15) of the small condenser, and the ultrasonic flowmeter (16) of the condensate of the small condenser are used to measure the pressure , temperature and flow rate .

[0025] Furthermore, the head and flow rate of the circulating water booster pump (5) of the small condenser are within the pressure constraint and flow rate constraint of the circulating water system of the small condenser (4).

[0026] Furthermore, the vacuum pump (7) of the small condenser can maintain the pressure in the small condenser (4) within a preset vacuum range.

[0027] Furthermore, the accuracy of the measuring device is within the allowable error range of the real-time determination of the exhaust steam enthalpy of the low-pressure cylinder.

[0028] Furthermore, the measuring device has a real-time data transmission function, and is used to transmit the measurement data to the data processing unit for calculation and analysis in real time.

[0029] In a second aspect, the present invention provides a method for real-time determination of the exhaust steam enthalpy of a steam turbine generator set, including:

[0030] The steam discharged from the low-pressure cylinder (1) is introduced into the small condenser (4) through the steam extraction pipeline of the small condenser.

[0031] During the process that the circulating water flows into the small condenser (4) introduced at the extraction point of the low-pressure cylinder exhaust steam through the circulating water inlet pipeline of the small condenser, the circulating water inlet pressure and temperature are collected by using the small condenser circulating water inlet pressure transmitter (12) and the small condenser circulating water inlet temperature transmitter (13), and the specific heat capacity at constant pressure of the circulating water inlet is calculated by using the IAPWS-IF97 water vapor property formula ;

[0032] When the circulating water is discharged through the circulating water outlet pipeline of the small condenser after heat exchange with the low-pressure cylinder exhaust steam in the small condenser (4), the temperature and pressure and flow rate of the circulating water outlet are measured by using the small condenser circulating water outlet temperature transmitter (10), the small condenser circulating water outlet pressure transmitter (11) and the small condenser circulating water outlet ultrasonic flowmeter (9), the specific heat capacity at constant pressure of the circulating water outlet is calculated by using the IAPWS-IF97 water vapor property formula , and the average specific heat capacity at constant pressure of the circulating water is calculated ;

[0033] When the steam in the small condenser (4) condenses into water and is discharged, the pressure , temperature and flow rate of the condensate are measured by using the small condenser condensate pressure transmitter (14), the small condenser condensate temperature transmitter (15) and the small condenser condensate ultrasonic flowmeter (16), and the enthalpy h_condensate of the small condenser condensate is calculated by using the IAPWS-IF97 water vapor property formula ;

[0034] Based on the principle of energy conservation, according to the average specific heat capacity at constant pressure of the circulating water , the flow rate of the circulating water outlet, the temperature of the circulating water outlet, the temperature of the circulating water inlet, the flow rate of the condensate, and the enthalpy h_condensate of the small condenser condensate , the enthalpy value of the low-pressure cylinder exhaust steam is calculated by using the IAPWS-IF97 water vapor property formula .

[0035] Furthermore, the expression for calculating the average specific heat capacity at constant pressure of the circulating water is expressed as:

[0036] ;

[0037] In the formula, represents the average constant pressure specific heat capacity of the circulating water, represents the constant pressure specific heat capacity of the inlet circulating water, represents the constant pressure specific heat capacity of the outlet circulating water.

[0038] Furthermore, the enthalpy value of the exhaust steam from the low-pressure cylinder is calculated using the IAPWS-IF97 water vapor property formula, expressed as:

[0039] ;

[0040] In the formula, represents the enthalpy value of the exhaust steam from the low-pressure cylinder, represents the average constant pressure specific heat capacity of the circulating water, represents the flow rate of the outlet circulating water, represents the temperature of the outlet circulating water, represents the temperature of the inlet circulating water, represents the flow rate of the condensate, represents the enthalpy h_condensate of the condensate in the small condenser.

[0041] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0042] 1. Compared with traditional measurement methods, the present invention only needs to measure the key parameters of the circulating water inlet and outlet and condensate of the small condenser, without a large number of complex sensors, greatly reducing the equipment investment cost. By using the measurement device and the thermodynamic model for calculation, the present invention effectively reduces the influence of measurement errors on the results. The measurement device obtains data from multiple dimensions and calculates based on the principle of energy conservation, capable of more accurately determining the enthalpy value of the exhaust steam from the low-pressure cylinder and providing more reliable data support for the optimization of unit operation. The present invention realizes the real-time measurement and calculation of the enthalpy value of the exhaust steam from the low-pressure cylinder, capable of timely reflecting the change of the exhaust steam enthalpy value during the operation of the unit. Operators can quickly adjust the operation parameters of the unit, such as the steam inlet volume of the steam turbine, the cooling water volume of the condenser, etc., according to the real-time data, so that the unit always maintains the best operation state, improves the thermal efficiency of the unit, reduces energy consumption, and enhances the economic efficiency and safety of the unit operation.

[0043] 2. The present invention extracts the exhaust steam of the low-pressure cylinder of the steam turbine through the exhaust steam pipeline of the low-pressure cylinder and introduces a specially arranged small condenser. By ingeniously utilizing the thermal balance characteristics of the small condenser to calculate the enthalpy value of the exhaust steam of the low-pressure cylinder, it realizes the measurement with fewer measurement parameters, effectively reducing the measurement error while reducing the measurement cost. This method can accurately and real-time measure the enthalpy value of the exhaust steam of the low-pressure cylinder, providing a solid and reliable data basis for the optimized operation of the thermal power generating unit. During specific implementation, the steam discharged from the low-pressure cylinder is introduced into the small condenser through the sampling and extraction steam pipeline of the small condenser, and the existing circulating water system is used for measurement, thus simplifying the measurement process. The system only needs to measure the key parameters of the inlet and outlet water of the circulating water of the small condenser and the condensate water, without configuring a large number of complex sensors, effectively reducing the equipment investment cost. At the same time, the measuring device has a real-time data transmission function, which can immediately transmit the measurement data to the data processing unit for calculation and analysis, further improving the efficiency and accuracy of data processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 FIG. is a schematic structural diagram of a real-time measurement system for the enthalpy of the exhaust steam of the low-pressure cylinder of a steam turbine generator set provided by an embodiment of the present invention;

[0045] Figure 2 FIG. is a schematic flow diagram of a real-time measurement method for the enthalpy of the exhaust steam of a steam turbine generator set provided by an embodiment of the present invention.

[0046] Reference numerals: 1 - low-pressure cylinder; 2 - condenser; 3 - circulating water pump; 4 - small condenser; 5 - booster pump for the circulating water of the small condenser; 6 - booster pump for the condensate water of the small condenser; 7 - vacuum pump for the small condenser; 8 - exhaust steam pressure transmitter of the low-pressure cylinder; 9 - ultrasonic flowmeter for the outlet water of the circulating water of the small condenser; 10 - outlet water temperature transmitter of the circulating water of the small condenser; 11 - outlet water pressure transmitter of the circulating water of the small condenser; 12 - inlet water pressure transmitter of the circulating water of the small condenser; 13 - inlet water temperature transmitter of the circulating water of the small condenser; 14 - condensate water pressure transmitter of the small condenser; 15 - condensate water temperature transmitter of the small condenser; 16 - ultrasonic flowmeter for the condensate water of the small condenser. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0047] The technical solution of the present invention will be described in detail below through the drawings and specific embodiments. It should be understood that the specific features in the embodiments of the present invention are detailed descriptions of the technical solution of the present invention, rather than limitations on the technical solution of the present invention. Without conflict, the technical features in the embodiments of the present invention and the embodiments can be combined with each other.

[0048] The term "and / or" is merely a description of the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. Additionally, the character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0049] Embodiment 1

[0050] This embodiment introduces a real-time measurement system for the exhaust enthalpy of the low-pressure cylinder of a steam turbine generator set, including:

[0051] As Figure 1 shown, the system provided in this embodiment includes the following key components: low-pressure cylinder 1, condenser 2, circulating water pump 3, small condenser 4, small condenser circulating water booster pump 5, small condenser condensate booster pump 6, small condenser vacuum pump 7, and a measuring device;

[0052] Among them, the exhaust steam of the low-pressure cylinder in the low-pressure cylinder exhaust steam pipeline is introduced into the small condenser (4). The small condenser circulating water booster pump (5) extracts circulating water from the outlet pipeline of the circulating water pump (3) to supply the small condenser (4) to cool the exhaust steam of the low-pressure cylinder. After heat exchange in the small condenser (4), the exhaust steam of the low-pressure cylinder condenses into water, which flows into the hot well of the condenser (2) after being boosted by the small condenser condensate booster pump (6). The small condenser vacuum pump (7) extracts the uncondensed gas in the small condenser (4) to keep the small condenser (4) at a low vacuum.

[0053] In this embodiment, the low-pressure cylinder 1 is used to generate exhaust steam. As the exhaust steam source of the real-time measurement system for the exhaust enthalpy of the low-pressure cylinder of the entire steam turbine generator set, during the operation of the steam turbine generator set, the steam in the low-pressure cylinder 1 is discharged after doing work.

[0054] In this embodiment, the condenser 2 is used for conventional steam condensation and undertakes the conventional steam condensation task.

[0055] In this embodiment, the circulating water pump 3 is used to provide power for the flow of circulating water to ensure that the circulating water can continuously and stably circulate between various components to achieve effective heat transfer.

[0056] In this embodiment, the small condenser 4 is used to receive the steam discharged and extracted from the low-pressure cylinder (1). It is one of the innovative components of the present invention. The small condenser 4 is mainly used to receive the extracted exhaust steam of the low-pressure cylinder (1). The present invention cleverly introduces the small condenser and uses the heat balance of the small condenser to calculate the exhaust enthalpy value of the low-pressure cylinder, so as to solve the problems of many measurement parameters, high cost, and large measurement error in the prior art, and realize the use of fewer measurement parameters to effectively reduce the measurement error while reducing the measurement cost, thereby accurately and real-time measuring the exhaust enthalpy value of the low-pressure cylinder.

[0057] In this embodiment, the small condenser circulating water booster pump 5 is used to increase the pressure of the small condenser circulating water, ensure that the circulating water can enter the small condenser 4 at an appropriate pressure, maintain the stable flow and efficient heat exchange of the circulating water in the small condenser 4, and the head and flow rate of the small condenser circulating water booster pump 5 are within the pressure constraint and flow constraint ranges of the small condenser 4 circulating water system.

[0058] In this embodiment, the small condenser condensate booster pump 6 is used to boost the pressure of the condensate in the hot well of the small condenser 4 supporting the small condenser and send it to the hot well of the main condenser, so that it can be smoothly sent to the hot well of the main condenser, realize the recovery and reuse of the condensate, and ensure the integrity of the water and steam cycle of the system.

[0059] In this embodiment, the small condenser air extraction vacuum pump 7 is used to extract the non-condensable gas in the small condenser 4 and maintain a high vacuum environment in the small condenser 4, and the small condenser air extraction vacuum pump 7 can keep the pressure in the small condenser 4 within the preset vacuum range.

[0060] In some embodiments, the measuring device includes a low-pressure cylinder exhaust pressure transmitter 8 installed on the low-pressure cylinder exhaust pipe, a small condenser circulating water outlet ultrasonic flowmeter 9, a small condenser circulating water outlet temperature transmitter 10, and a small condenser circulating water outlet pressure transmitter 11 respectively installed on the small condenser circulating water outlet pipe, a small condenser circulating water inlet pressure transmitter 12 and a small condenser circulating water inlet temperature transmitter 13 installed on the small condenser circulating water inlet pipe, and a small condenser condensate pressure transmitter 14, a small condenser condensate temperature transmitter 15, and a small condenser condensate ultrasonic flowmeter 16 installed on the small condenser condensate pipe.

[0061] Compared with the commonly used differential pressure flowmeter, the condenser condensate ultrasonic flowmeter 16 used in this embodiment has the advantage of a large range ratio. The range ratio of the commonly used differential pressure flowmeter is generally 3:1, and the range ratio of the small condenser condensate ultrasonic flowmeter 16 used in this embodiment can generally reach 10:1 or even higher, which can meet the accurate measurement from a very small flow rate to an extremely large flow rate.

[0062] In this embodiment, the low-pressure cylinder exhaust pressure transmitter 8 is used to measure the low-pressure cylinder exhaust pressure in real time .

[0063] In this embodiment, the small condenser circulating water outlet ultrasonic flowmeter 9, the small condenser circulating water outlet temperature transmitter 10, and the small condenser circulating water outlet pressure transmitter 11 are used to monitor the flow rate , temperature and pressure of the circulating water outlet in real time.

[0064] In this embodiment, the small condenser circulating water inlet pressure transmitter 12 and the small condenser circulating water inlet temperature transmitter 13 are used to measure the pressure of the circulating water inlet and temperature .

[0065] In this embodiment, the small condenser condensate pressure transmitter 14, the small condenser condensate temperature transmitter 15, and the small condenser condensate ultrasonic flowmeter 16 are used to measure the pressure of the small condenser condensate in real time 、temperature and flow rate .

[0066] In this embodiment, the accuracy of the measuring device is within the allowable error range of the real-time determination of the exhaust enthalpy of the low-pressure cylinder. The measuring device also has a real-time data transmission function for transmitting the measured data to the data processing unit in real time for calculation and analysis.

[0067] Embodiment 2

[0068] Based on the same inventive concept as Embodiment 1, as Figure 2 shown, this embodiment introduces a method for real-time determination of the exhaust enthalpy of a steam turbine generator set, including:

[0069] Step 1: Introduce the steam discharged from the low-pressure cylinder 1 into the small condenser 4 through the small condenser sampling steam extraction pipeline.

[0070] In this embodiment, by designing the small condenser sampling steam extraction pipeline to connect the exhaust port of the low-pressure cylinder 1 and the steam inlet of the small condenser 4, and stably introducing the steam discharged from the low-pressure cylinder 1 into the interior of the small condenser 4, the sealing and smoothness of the steam extraction pipeline are ensured, preventing steam leakage or blockage, and ensuring the stability of the exhaust steam flow rate and pressure entering the small condenser 4.

[0071] Step 2: During the process of the circulating water flowing into the small condenser 4 introduced at the extraction point of the low-pressure cylinder exhaust steam through the small condenser circulating water inlet pipeline, use the small condenser circulating water inlet pressure transmitter 12 and the small condenser circulating water inlet temperature transmitter 13 to collect the pressure of the circulating water inlet , temperature , and calculate the constant-pressure specific heat capacity of the circulating water inlet using the IAPWS-IF97 water vapor property formula .

[0072] In this embodiment, the circulating water is made to flow into the small condenser 4 through the small condenser circulating water pump through the small condenser circulating water inlet pipeline. During the process of the circulating water inlet, the small condenser circulating water inlet pressure transmitter 12 and the small condenser circulating water inlet temperature transmitter 13 collect the pressure of the circulating water inlet in real time , temperature 。

[0073] In this embodiment, the IAPWS-IF97 water vapor property formula of the International Association for the Properties of Water and Steam is adopted, and the specific heat capacity at constant pressure of the circulating water inlet is calculated by using the pressure P3 and temperature T3 of the circulating water inlet 。

[0074] Step 3: When the circulating water is discharged through the small condenser circulating water outlet pipe after heat exchange with the low-pressure cylinder exhaust steam in the small condenser (4), the temperature of the circulating water outlet is measured by using the small condenser circulating water outlet temperature transmitter (10), the small condenser circulating water outlet pressure transmitter (11) and the small condenser circulating water outlet ultrasonic flowmeter (9) 、pressure and flow , and the specific heat capacity at constant pressure of the circulating water outlet is calculated by using the IAPWS - IF97 water vapor property formula , and the average specific heat capacity at constant pressure of the circulating water is calculated 。

[0075] In this embodiment, the IAPWS-IF97 water vapor property formula of the International Association for the Properties of Water and Steam is adopted, and the specific heat capacity at constant pressure of the circulating water outlet is calculated by using the pressure and temperature of the circulating water outlet 。

[0076] In this embodiment, the expression for calculating the average specific heat capacity at constant pressure of the circulating water is expressed as:

[0077] ;

[0078] In the formula, represents the average specific heat capacity at constant pressure of the circulating water, represents the specific heat capacity at constant pressure of the circulating water inlet, represents the specific heat capacity at constant pressure of the circulating water outlet

[0079] Step 4: When the steam in the small condenser (4) condenses into water and is discharged, the pressure of the condensate is measured by using the small condenser condensate pressure transmitter (14), the small condenser condensate temperature transmitter (15) and the small condenser condensate ultrasonic flowmeter (16) 、temperature and flow , and the enthalpy h of the small condenser condensate is calculated by using the IAPWS - IF97 water vapor property formula 。

[0080] This embodiment adopts the IAPWS-IF97 water vapor property formula of the International Association for the Properties of Water and Steam, and uses the pressure of the condensate water in the small condenser , temperature to calculate the enthalpy h_condensate of the condensate water in the small condenser .

[0081] Step 5: Based on the principle of energy conservation, according to the average constant-pressure specific heat capacity of the circulating water , the flow rate of the outlet water of the circulating water , the temperature of the outlet water of the circulating water , the inlet temperature of the circulating water , the flow rate of the condensate water , the enthalpy h_condensate of the condensate water in the small condenser , use the IAPWS - IF97 water vapor property formula to calculate the enthalpy value of the exhaust steam from the low-pressure cylinder .

[0082] In this embodiment, using the IAPWS - IF97 water vapor property formula to calculate the enthalpy value of the exhaust steam from the low-pressure cylinder is expressed as:

[0083] ;

[0084] In the formula, represents the enthalpy value of the exhaust steam from the low-pressure cylinder, represents the average constant-pressure specific heat capacity of the circulating water, represents the flow rate of the outlet water of the circulating water, represents the temperature of the outlet water of the circulating water, represents the inlet temperature of the circulating water, represents the flow rate of the condensate water, represents the enthalpy h_condensate of the condensate water in the small condenser.

[0085] Embodiment 3

[0086] Based on the same inventive concept as other embodiments, this embodiment introduces a computer-readable storage medium, on which computer instructions are stored, and when the computer instructions are executed by a processor, the steps of the method in the above Embodiment 1 or 2 are implemented.

[0087] Embodiment 4

[0088] Based on the same inventive concept as other embodiments, this embodiment introduces a computer program product, including computer instructions, and when the computer instructions are executed by a processor, the steps of the method in the above Embodiment 1 or 2 are implemented.

[0089] In summary, compared with traditional measurement methods, the present invention only needs to measure the key parameters of the circulating water inlet and outlet of the small condenser and the condensate water, without a large number of complex sensors, greatly reducing the equipment investment cost. By using the measurement device and the thermodynamic model for calculation, the present invention effectively reduces the influence of measurement errors on the results. The measurement device obtains data from multiple dimensions and calculates based on the principle of energy conservation, which can more accurately determine the exhaust enthalpy value of the low-pressure cylinder and provide more reliable data support for the optimization of unit operation. The present invention realizes the real-time measurement and calculation of the exhaust enthalpy value of the low-pressure cylinder, and can timely reflect the change of the exhaust enthalpy value during the operation of the unit. Operators can quickly adjust the operation parameters of the unit, such as the steam inlet volume of the steam turbine, the cooling water volume of the condenser, etc., according to the real-time data, so that the unit always maintains the best operation state, improves the thermal efficiency of the unit, reduces energy consumption, and enhances the economy and safety of unit operation.

[0090] The present invention extracts the exhaust steam of the steam turbine's low-pressure cylinder from the exhaust steam pipeline of the low-pressure cylinder and introduces a specially set small condenser, and cleverly uses the heat balance characteristics of the small condenser to calculate the exhaust enthalpy value of the low-pressure cylinder, realizing the use of fewer measurement parameters to effectively reduce the measurement error while reducing the measurement cost. This method can accurately and real-time determine the exhaust enthalpy value of the low-pressure cylinder and provides a solid and reliable data basis for the optimized operation of thermal power generating units. During specific implementation, the steam exhausted from the low-pressure cylinder is introduced into the small condenser through the sampling and extraction steam pipeline of the small condenser, and the existing circulating water system is used for measurement, thus simplifying the measurement process. The system only needs to measure the key parameters of the circulating water inlet and outlet and the condensate water of the small condenser, without configuring a large number of complex sensors, effectively reducing the equipment investment cost. At the same time, the measurement device has a real-time data transmission function and can immediately transmit the measurement data to the data processing unit for calculation and analysis, further improving the efficiency and accuracy of data processing.

[0091] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0092] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general purpose computer, a special purpose computer, an embedded processor, or other programmable data processing device to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing device generate means for implementing the functions specified in the flow Figure 1 one flow or multiple flows and / or blocks Figure 1 means for implementing the functions specified in one block or multiple blocks.

[0093] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory produce a manufactured article including instruction means that implement the functions specified in the flow Figure 1 one flow or multiple flows and / or blocks Figure 1 means for implementing the functions specified in one block or multiple blocks.

[0094] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in the flow Figure 1 one flow or multiple flows and / or blocks Figure 1 means for implementing the functions specified in one block or multiple blocks.

[0095] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit and scope protected by the present invention and the claims. These all fall within the protection scope of the present invention.

Claims

1. A real-time measurement system for the exhaust enthalpy of the low-pressure cylinder of a steam turbine generator set, characterized in that, Comprising: A low-pressure cylinder (1), a condenser (2), a circulating water pump (3), a small condenser (4), a small condenser circulating water booster pump (5), a small condenser condensate booster pump (6), a small condenser air extraction pump (7), and a measuring device; Wherein, the low-pressure steam exhausted from the low-pressure cylinder is extracted from the low-pressure cylinder exhaust pipe and introduced into the small condenser (4). The small condenser circulating water booster pump (5) extracts circulating water from the outlet pipe of the circulating water pump (3) to supply the small condenser (4) to cool the low-pressure cylinder exhaust steam. After heat exchange in the small condenser (4), the low-pressure cylinder exhaust steam condenses into water, which flows into the hot well of the condenser (2) after being boosted by the small condenser condensate booster pump (6). The small condenser air extraction pump (7) extracts the non-condensed gas in the small condenser (4) to keep the small condenser (4) at a low vacuum; The measuring device includes: A low-pressure cylinder exhaust pressure transmitter (8) installed on the low-pressure cylinder exhaust pipe; A small condenser circulating water outlet ultrasonic flowmeter (9), a small condenser circulating water outlet temperature transmitter (10), and a small condenser circulating water outlet pressure transmitter (11) respectively installed on the small condenser circulating water outlet pipe; A small condenser circulating water inlet pressure transmitter (12) and a small condenser circulating water inlet temperature transmitter (13) installed on the small condenser circulating water inlet pipe; A small condenser condensate pressure transmitter (14), a small condenser condensate temperature transmitter (15), and a small condenser condensate ultrasonic flowmeter (16) installed on the small condenser condensate pipe.

2. The real-time measurement system for the enthalpy of the low-pressure cylinder exhaust of a steam turbine generator set according to claim 1, characterized in that The low-pressure cylinder (1) generates exhaust steam; The condenser (2) is used for condensing the conventional low-pressure cylinder exhaust steam; The circulating water pump (3) is used to provide power for the flow of circulating water; The small condenser (4) is used to cool the steam extracted from the exhaust pipe of the low-pressure cylinder (1); The small condenser circulating water booster pump (5) is used to increase the pressure of the small condenser circulating water; The small condenser condensate booster pump (6) is used to boost the condensate water in the hot well of the small condenser and send it to the hot well of the main condenser; The small condenser air extraction pump (7) is used to extract the non-condensable gas in the small condenser (4).

3. The real-time measurement system for the enthalpy of the low-pressure cylinder exhaust of a steam turbine generator set according to claim 1, characterized in that The low-pressure cylinder exhaust pressure transmitter (8) is used to measure the low-pressure cylinder exhaust pressure in real time ; The ultrasonic flowmeter (9) for the outlet circulating water of the small condenser, the temperature transmitter (10) for the outlet circulating water of the small condenser, and the pressure transmitter (11) for the outlet circulating water of the small condenser are used to monitor the flow rate , temperature , and pressure ; The small condenser circulating water inlet pressure transmitter (12) and the small condenser circulating water inlet temperature transmitter (13) are used to measure the pressure and temperature ; The condensate pressure transmitter (14) of the small condenser, the condensate temperature transmitter (15) of the small condenser, and the condensate ultrasonic flowmeter (16) of the small condenser are used to measure the pressure of the condensate in the small condenser in real time , temperature and flow rate .

4. The real-time steam exhaust enthalpy measurement system for the low-pressure cylinder of a steam turbine generator set according to claim 1, wherein The head and flow rate of the small condenser circulating water booster pump (5) are within the pressure constraint and flow constraint range of the small condenser (4) circulating water system.

5. The real-time exhaust enthalpy measurement system for the low-pressure cylinder of a steam turbine generator set according to claim 1, wherein The small condenser air extraction pump (7) can keep the pressure in the small condenser (4) within a preset vacuum range.

6. The real-time exhaust enthalpy measurement system for the low-pressure cylinder of a steam turbine generator set according to claim 1, wherein The accuracy of the measuring device is within the allowable error range for the real-time measurement of the enthalpy of the low-pressure cylinder exhaust.

7. The real-time exhaust enthalpy measurement system for the low-pressure cylinder of a steam turbine generator set according to claim 1, wherein The measuring device has a real-time data transmission function and is used to transmit the measurement data to the data processing unit for calculation and analysis in real time.

8. The real-time measurement method for the exhaust enthalpy of the low-pressure cylinder of a steam turbine generator set according to any one of claims 1-7, characterized in that, Comprising: The steam exhausted from the low-pressure cylinder (1) is introduced into the small condenser (4) through the small condenser steam extraction pipe; During the process that the circulating water flows into the small condenser (4) introduced at the extraction point of the exhaust steam of the low-pressure cylinder through the circulating water inlet pipeline of the small condenser, the circulating water inlet pressure transmitter (12) and the circulating water inlet temperature transmitter (13) of the small condenser are used to collect the circulating water inlet pressure , temperature , and the IAPWS-IF97 water vapor property formula is used to calculate the specific heat capacity at constant pressure of the circulating water inlet ; When the circulating water is discharged through the outlet pipe of the small condenser circulating water after heat exchange with the exhaust steam of the low-pressure cylinder in the small condenser (4), the temperature of the circulating water outlet is measured by the temperature transmitter (10) of the small condenser circulating water outlet, the pressure transmitter (11) of the small condenser circulating water outlet, and the ultrasonic flowmeter (9) of the small condenser circulating water outlet , pressure and flow rate . The IAPWS-IF97 water vapor property formula is used to calculate the specific heat capacity at constant pressure of the circulating water outlet , and the average specific heat capacity at constant pressure of the circulating water is calculated ; When the steam in the small condenser (4) condenses into water and is discharged, the condensate pressure of the small condenser is measured by the small condenser condensate pressure transmitter (14), the small condenser condensate temperature transmitter (15) and the small condenser condensate ultrasonic flowmeter (16). , temperature and flow rate , and the enthalpy hcondensate of the small condenser condensate is calculated using the IAPWS - IF97 water vapor property formula ; Based on the principle of energy conservation, according to the average isobaric specific heat capacity of the cycle , the flow rate of the circulating water outlet , the temperature of the circulating water outlet , the temperature of the circulating water inlet , the flow rate of the condensate , the enthalpy h of the condensate in the small condenser , calculate the enthalpy value of the low-pressure cylinder exhaust steam using the IAPWS-IF97 water vapor property formula .

9. The real-time measurement method for the exhaust enthalpy of the low-pressure cylinder of a steam turbine generator set according to claim 8, characterized in that, Calculating the average constant pressure specific heat capacity of the cycle The expression is represented as: ； In the formula, represents the average constant-pressure specific heat capacity of the circulating water, represents the constant-pressure specific heat capacity of the inlet circulating water, represents the constant-pressure specific heat capacity of the outlet circulating water.

10. The real-time measurement method for the exhaust enthalpy of the low-pressure cylinder of a steam turbine generator set according to claim 8, characterized in that, The enthalpy value of the exhaust steam from the low-pressure cylinder is calculated using the IAPWS-IF97 water vapor property formula, expressed as: ； In the formula, represents the exhaust enthalpy value of the low-pressure cylinder, represents the average constant-pressure specific heat capacity of the circulating water, represents the flow rate of the outlet water of the circulating water, represents the temperature of the outlet water of the circulating water, represents the inlet temperature of the circulating water, represents the flow rate of the condensate, represents the enthalpy h of the condensate in the small condenser.

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