Method and system for monitoring outlet steam temperature of a nuclear power plant steam generator

Abstract

The application provides a kind of nuclear power plant steam generator outlet steam temperature monitoring method and system, and monitoring method includes the following steps: establishing temperature deviation standard model;In the reactor at a certain power state, the outlet actual temperature of each to-be-tested heat transfer tube of outlet steam tube plate is collected, and the average temperature is calculated according to the outlet actual temperature of each to-be-tested heat transfer tube, and the maximum deviation value between the outlet actual temperature of each to-be-tested heat transfer tube of outlet steam tube plate and the average temperature;According to the comparison result of the maximum deviation value and the temperature deviation standard value, it is determined whether to adjust the thermal parameter of steam generator so that the maximum deviation value is not greater than the temperature deviation standard value.The technical effect of the application is that the temperature of each position of outlet steam tube plate can be monitored, and the temperature of each position of outlet steam tube plate is controlled to be uniform.

Description

Technical Field

[0001] This invention belongs to the field of high-temperature gas-cooled reactor technology, specifically relating to a method and system for monitoring the outlet steam temperature of a nuclear power plant steam generator. Background Technology

[0002] The steam generator of the high-temperature gas-cooled reactor nuclear power plant adopts a modular heat exchange unit with a total of 19 heat exchange components. Each heat exchange component consists of 5 layers of multiple spiral coil heat transfer tubes. This arrangement of heat exchange components makes the steam generator compact, has high heat exchange efficiency, and allows for the arrangement of longer heat transfer tubes within a certain volume of steam generator, which is beneficial for heating feedwater into high-superheated outlet steam.

[0003] The high-temperature gas-cooled reactor steam generator has 665 heat transfer tubes. These tubes converge at the outlet steam tube sheet. The steam from these 665 tubes mixes at the outlet steam header after passing through the tube sheet to become the main steam. However, this arrangement also presents certain problems. When the reactor's primary coolant, helium, enters the steam generator for heat exchange, the different positions of each heat exchange assembly and each heat transfer tube within the assembly result in varying heat exchange efficiency. Consequently, the steam temperature at the outlet of each heat transfer tube differs. This temperature difference at the outlet of different heat transfer tubes causes thermal stress on the outlet tube sheet. If the temperature deviation is too large, the resulting thermal stress will be excessive, threatening the safety of the steam generator's outlet tube sheet.

[0004] Therefore, how to effectively monitor the temperature at the outlet of the heat transfer tube of the steam generator and avoid excessive deviation in the steam temperature at the outlet of the steam generator has become an urgent technical problem to be solved. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art, and to provide a new technical solution for a method and system for monitoring the outlet steam temperature of a nuclear power plant steam generator.

[0006] According to a first aspect of the embodiments of this application, a method for monitoring the outlet steam temperature of a nuclear power plant steam generator is provided, comprising the following steps:

[0007] Step S100: Establish a temperature deviation standard model; wherein, the temperature deviation standard model includes standard values ​​of temperature deviation for the outlet steam tube sheet under various reactor power conditions.

[0008] Step S200: Under a certain power state of the reactor, the actual outlet temperature of each heat transfer tube to be tested on the outlet steam tube sheet is collected, and the average temperature and the maximum deviation between the actual outlet temperature of each heat transfer tube to be tested and the average temperature are calculated based on the actual outlet temperature of each heat transfer tube to be tested.

[0009] Step S300: Based on the comparison between the maximum deviation value and the standard value of temperature deviation under a certain power state of the reactor, determine whether to adjust the thermal parameters of the steam generator so that the maximum deviation value is not greater than the standard value of temperature deviation.

[0010] Optionally, the thermal parameters of the steam generator include the flow rate of helium in the primary loop, the temperature of helium in the primary loop, the flow rate of feedwater in the secondary loop, and the temperature of feedwater in the secondary loop.

[0011] Optionally, adjusting the thermal parameters of the steam generator includes:

[0012] Adjust at least one of the following: the flow rate of helium in the primary loop, the temperature of helium in the primary loop, the flow rate of water in the secondary loop, and the temperature of water in the secondary loop.

[0013] Optionally, after adjusting the thermal parameters of the steam generator so that the maximum deviation value is not greater than the temperature deviation standard value, the outlet regulation temperature of each heat transfer tube to be tested on the outlet steam tube sheet is collected, and the regulation deviation value of the outlet steam tube sheet is calculated based on the outlet regulation temperature.

[0014] The temperature deviation standard model is optimized based on a certain power state of the reactor, the thermal parameters of the steam generator, the outlet regulating temperature, and the regulating deviation value.

[0015] Optionally, the actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet is collected, including:

[0016] A preset number of thermocouples are installed on the outlet steam tube sheet, and each thermocouple corresponds to the outlet of a heat transfer tube to be tested;

[0017] The actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet is obtained based on the temperature measurement values ​​of each thermocouple.

[0018] Optionally, each heat transfer tube in the steam generator is provided with a thermocouple at its outlet.

[0019] Optionally, the steam generator includes 19 heat exchange components, which are distributed at intervals along a circular plane; each heat exchange component includes 5 sub-units, and each sub-unit includes multiple heat transfer tubes.

[0020] A thermocouple is installed at the outlet of each heat transfer tube of the heat exchange assembly located in the middle of the circular plane;

[0021] In each sub-unit of each heat exchange component located at the edge of the circular plane, at least one heat transfer tube outlet is provided with a thermocouple.

[0022] According to a second aspect of the embodiments of this application, a monitoring system for the outlet steam temperature of a nuclear power plant steam generator is provided, comprising:

[0023] The data processing module is used to establish a temperature deviation standard model; wherein, the temperature deviation standard model includes standard values ​​of temperature deviation of the outlet steam tube sheet under various reactor power states.

[0024] The monitoring module is used to collect the actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet when the reactor is at a certain power state, and to calculate the average temperature and the maximum deviation between the actual outlet temperature of each heat transfer tube under test and the average temperature based on the actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet.

[0025] The control module is used to determine whether to adjust the thermal parameters of the steam generator so that the maximum deviation value is not greater than the temperature deviation standard value, based on the comparison result between the maximum deviation value and the temperature deviation standard value under a certain power state of the reactor.

[0026] According to a third aspect of the embodiments of this application, an electronic device is provided, including a monitoring system for the outlet steam temperature of a nuclear power plant steam generator as described in the second aspect; or,

[0027] The device includes: a processor and a memory;

[0028] The memory is used to store executable instructions for controlling the processor to execute the method for monitoring the outlet steam temperature of a nuclear power plant steam generator according to the first aspect.

[0029] According to a fourth aspect of the embodiments of this application, a computer storage medium is provided, the storage medium storing computer instructions, which, when executed by a processor, implement the method for monitoring the outlet steam temperature of a nuclear power plant steam generator as described in the first aspect.

[0030] One technical advantage of this invention is that:

[0031] In this embodiment of the application, the method for monitoring the outlet steam temperature of the nuclear power plant steam generator can effectively monitor the outlet temperature and maximum temperature difference of each heat transfer tube of the steam generator, and effectively adjust the thermal parameters of the steam generator based on the monitoring results, so that the actual temperature difference of the outlet steam tube sheet is not greater than the temperature deviation standard value, that is, the temperature at each position of the outlet steam tube sheet is relatively uniform, thereby ensuring the safe operation of the steam generator and having great application value. Attached Figure Description

[0032] Figure 1 This is a flowchart illustrating a method for monitoring the outlet steam temperature of a nuclear power plant steam generator according to an embodiment of the present invention.

[0033] Figure 2 This is a schematic block diagram illustrating a method for monitoring the outlet steam temperature of a nuclear power plant steam generator according to an embodiment of the present invention. Detailed Implementation

[0034] Various exemplary embodiments of this application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this application.

[0035] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0036] According to a first aspect of the embodiments of this application, such as Figure 1 As shown, a method for monitoring the outlet steam temperature of a nuclear power plant steam generator is provided. This method is applied to a high-temperature gas-cooled reactor nuclear power plant and can monitor the temperature at various locations on the outlet steam tube sheet and control the temperature at each location on the outlet steam tube sheet to be uniform.

[0037] Specifically, the method for monitoring the outlet steam temperature of a nuclear power plant steam generator includes the following steps:

[0038] Step S100: Establish a temperature deviation standard model; wherein the temperature deviation standard model includes standard values ​​of temperature deviation for the outlet steam tube sheet under various reactor power conditions.

[0039] In one specific implementation, the temperature deviation standard model also includes the thermal standard parameters of the steam generator under various reactor power states. The steam generator under a certain power state can be quickly and accurately adjusted according to the thermal standard parameters of the steam generator. The operation is very simple and helps to ensure the stability of the steam generator operation.

[0040] Step S200: Under a certain power state of the reactor, the actual outlet temperature of each heat transfer tube to be tested on the outlet steam tube sheet is collected, and the average temperature and the maximum deviation between the actual outlet temperature of each heat transfer tube to be tested and the average temperature are calculated based on the actual outlet temperature of each heat transfer tube to be tested on the outlet steam tube sheet.

[0041] It should be noted that during reactor operation, the average temperature is calculated as the sum of the actual outlet temperatures of each heat transfer tube under test on the steam tube sheet, which is also the steam outlet temperature of the steam generator.

[0042] For example, whether the temperature of one heat transfer tube under test is too high or the temperature of multiple heat transfer tubes under test is too high, the temperature non-uniformity at various locations of the outlet steam tube sheet can be determined by calculating the maximum deviation value. This can remind the operator to adjust the thermal parameters of the steam generator, thereby achieving temperature uniformity at various locations of the outlet steam tube sheet and ensuring the safe and stable operation of the steam generator.

[0043] Step S300: Based on the comparison between the maximum deviation value and the standard value of temperature deviation under a certain power state of the reactor, determine whether to adjust the thermal parameters of the steam generator so that the maximum deviation value is not greater than the standard value of temperature deviation.

[0044] When the maximum deviation exceeds the standard temperature deviation value for a certain power state of the reactor, an alarm signal is generated to prompt the operator to adjust the thermal parameters of the steam generator until the maximum deviation does not exceed the standard temperature deviation value. When the maximum deviation does not exceed the standard temperature deviation value for a certain power state of the reactor, no alarm signal is generated, indicating that the steam generator is operating stably.

[0045] In this embodiment of the application, the method for monitoring the outlet steam temperature of the nuclear power plant steam generator can effectively monitor the outlet temperature and maximum temperature difference of each heat transfer tube of the steam generator, and effectively adjust the thermal parameters of the steam generator based on the monitoring results, so that the actual temperature difference of the outlet steam tube sheet is not greater than the temperature deviation standard value, that is, the temperature at each position of the outlet steam tube sheet is relatively uniform, thereby ensuring the safe operation of the steam generator and having great application value.

[0046] Optionally, the thermal parameters of the steam generator include the flow rate and temperature of the primary loop helium, the flow rate and temperature of the secondary loop feedwater. This makes adjusting the thermal parameters of the steam generator very simple and effective, helps to quickly reduce the outlet steam temperature difference of the nuclear power plant steam generator, and ensures that the temperature is more uniform at various locations on the outlet steam tube sheet, thus guaranteeing the safe operation of the steam generator.

[0047] Optionally, adjusting the thermal parameters of the steam generator includes:

[0048] The system allows adjustment of at least one of the following: the flow rate and temperature of helium in the primary circuit; the flow rate and temperature of water in the secondary circuit; and the overall operation is simple.

[0049] Optionally, after adjusting the thermal parameters of the steam generator so that the maximum deviation value is not greater than the temperature deviation standard value, the outlet regulation temperature of each heat transfer tube to be tested on the outlet steam tube sheet is collected, and the regulation deviation value of the outlet steam tube sheet is calculated based on the outlet regulation temperature.

[0050] The temperature deviation standard model is optimized based on a certain power state of the reactor, the thermal parameters of the steam generator, the outlet regulating temperature, and the regulating deviation value.

[0051] After adjusting the thermal parameters of the steam generator, the temperature at various locations on the outlet steam tube sheet becomes more uniform. Furthermore, by optimizing the temperature deviation standard model using the adjusted thermal parameters, the accuracy of the temperature deviation standard model is ensured. This helps provide reliable control parameters for the stable operation of the steam generator and facilitates operator adjustments.

[0052] Optionally, the actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet is collected, including:

[0053] A preset number of thermocouples are installed on the outlet steam tube sheet, and each thermocouple corresponds to the outlet of a heat transfer tube to be tested;

[0054] The actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet is obtained based on the temperature measurement values ​​of each thermocouple.

[0055] In the above embodiments, thermocouples can accurately monitor the actual outlet temperature of each heat transfer tube under test in the outlet steam tube sheet, which helps to ensure the accuracy of the monitoring results and thus better guide the safe operation of the steam generator.

[0056] Optionally, each heat transfer tube in the steam generator is provided with a thermocouple at its outlet.

[0057] In the above implementation, each thermocouple can accurately monitor the actual outlet temperature of all heat transfer tubes in the outlet steam tube sheet, which helps to ensure the accuracy of the monitoring results and thus better guide the safe operation of the steam generator.

[0058] Optionally, the steam generator includes 19 heat exchange components, which are distributed at intervals along a circular plane; each heat exchange component includes 5 sub-units, and each sub-unit includes multiple heat transfer tubes.

[0059] A thermocouple is installed at the outlet of each heat transfer tube of the heat exchange assembly located in the middle of the circular plane;

[0060] In each sub-unit of each heat exchange component located at the edge of the circular plane, at least one heat transfer tube outlet is provided with a thermocouple.

[0061] In the above embodiments, the placement and number of thermocouples are reasonable, which can reduce the number of thermocouples and accurately monitor the actual outlet temperature at each position of the outlet steam tube sheet, thus facilitating effective control of the uniformity of the outlet steam temperature of the steam generator.

[0062] In one specific implementation, a certain number of thermocouples are installed on the outlet steam tube sheet of the steam generator. Each thermocouple is used to measure the outlet steam temperature of its corresponding individual heat transfer tube. The arrangement of the thermocouples takes into account the arrangement of the heat exchange components to which each heat transfer tube belongs and the operability on site. Based on the temperature values ​​measured by each thermocouple, the actual outlet temperature of each heat transfer tube and the average temperature of each heat transfer tube are calculated. Then, the actual outlet deviation value of each heat transfer tube (i.e., the steam temperature deviation at the outlet of the steam generator) is calculated. When the actual outlet deviation value of each heat transfer tube meets the temperature deviation standard model, that is, when the maximum deviation value of each heat transfer tube is not greater than the temperature deviation standard value under a certain power state of the reactor, the uniformity of the steam temperature at the outlet of the steam generator is qualified. If the temperature deviation of one or more heat transfer tubes from the average temperature exceeds the temperature deviation standard value, the thermal parameters of the steam generator need to be adjusted to make the steam temperature deviation at the outlet of the steam generator tend to be consistent and meet the uniformity requirements.

[0063] The calculation method for the outlet temperature deviation of a single heat transfer tube is as follows:

[0064] The average temperature T(avg) = (∑Ti) / 19, (i = 1~19), where Ti = the average temperature of each measuring point in the tube bundle of the i-th heat exchange component.

[0065] Temperature deviation δT=Ti-T(avg).

[0066] It should be noted that the 19 groups in the embodiments of this application are the number of heat exchange components of the steam generator in the demonstration project. The number of steam generators of the same type can be determined according to the actual situation.

[0067] The above algorithm is integrated into the DCS system. When the uniformity deviation of the temperature values ​​at all temperature measuring points meets the requirements, the system operates stably without alarms. When the measured value of the steam temperature at the outlet of one or more heat transfer tubes exceeds the uniformity criterion, a large temperature deviation alarm signal is generated and displayed in the DCS system. While maintaining stable unit power, the deviation of the steam generator outlet temperature is restored to meet the uniformity criterion by adjusting one or more of the following: the flow rate and temperature of the primary loop helium, the flow rate and temperature of the secondary loop feedwater. When there is no large temperature deviation alarm signal, a set of thermal operating parameters matching the uniformity of the steam generator outlet steam temperature under a certain power state is obtained, serving as the reference values ​​for controlling the steam generator under this power state. After obtaining the corresponding thermal parameters of the steam generator matching the temperature uniformity under various power states of the unit, the reference parameters for controlling the uniformity of the steam generator outlet steam temperature during the stable operation phase of the unit are obtained, i.e., the temperature deviation standard model, which guides the adjustment and control of the unit's thermal parameters. (See [link to relevant documentation]). Figure 2 .

[0068] According to a second aspect of the embodiments of this application, a monitoring system for the outlet steam temperature of a nuclear power plant steam generator is provided, comprising:

[0069] The data processing module is used to establish a temperature deviation standard model; wherein, the temperature deviation standard model includes standard values ​​of temperature deviation of the outlet steam tube sheet under various reactor power states.

[0070] The monitoring module is used to collect the actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet when the reactor is at a certain power state, and to calculate the average temperature and the maximum deviation between the actual outlet temperature of each heat transfer tube under test and the average temperature based on the actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet.

[0071] The control module is used to determine whether to adjust the thermal parameters of the steam generator so that the maximum deviation value is not greater than the temperature deviation standard value, based on the comparison result between the maximum deviation value and the temperature deviation standard value under a certain power state of the reactor.

[0072] In this embodiment, the monitoring system for the outlet steam temperature of the nuclear power plant steam generator can monitor the temperature at various locations on the outlet steam tube sheet and control the temperature at each location on the outlet steam tube sheet to be uniform.

[0073] According to a third aspect of the embodiments of this application, an electronic device is provided, including a monitoring system for the outlet steam temperature of a nuclear power plant steam generator as described in the second aspect; or,

[0074] The device includes: a processor and a memory;

[0075] The memory is used to store executable instructions for controlling the processor to execute the method for monitoring the outlet steam temperature of a nuclear power plant steam generator according to the first aspect.

[0076] According to a fourth aspect of the present application, a computer storage medium is provided, the storage medium storing computer instructions, which, when executed by a processor, implement the method for monitoring the outlet steam temperature of a nuclear power plant steam generator as described in the first aspect.

[0077] The computer-readable medium may be included in the apparatus, device, or system of the present invention, or it may exist independently.

[0078] The computer-readable storage medium may be any tangible medium that contains or stores a program, and may be an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device. More specific examples include, but are not limited to, electrical connections having one or more wires, portable computer disks, hard disks, optical fibers, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0079] The computer-readable storage medium may also include data signals propagated in baseband or as part of a carrier wave, carrying computer-readable program code, specific examples of which include, but are not limited to, electromagnetic signals, optical signals, or any suitable combination thereof.

[0080] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for monitoring the outlet steam temperature of a nuclear power plant steam generator, characterized in that, Includes the following steps: Step S100: Establish a temperature deviation standard model; wherein, the temperature deviation standard model includes standard values ​​of temperature deviation for the outlet steam tube sheet under various reactor power conditions. Step S200: Under a certain power state of the reactor, the actual outlet temperature of each heat transfer tube to be tested on the outlet steam tube sheet is collected, and the average temperature and the maximum deviation between the actual outlet temperature of each heat transfer tube to be tested and the average temperature are calculated based on the actual outlet temperature of each heat transfer tube to be tested. Step S300: Based on the comparison between the maximum deviation value and the standard temperature deviation value under a certain power state of the reactor, determine whether to adjust the thermal parameters of the steam generator so that the maximum deviation value does not exceed the standard temperature deviation value; wherein, The thermal parameters of the steam generator include the flow rate of helium in the primary loop, the temperature of helium in the primary loop, the flow rate of feedwater in the secondary loop, and the temperature of feedwater in the secondary loop; adjusting the thermal parameters of the steam generator includes adjusting at least one of the flow rate of helium in the primary loop, the temperature of helium in the primary loop, the flow rate of feedwater in the secondary loop, and the temperature of feedwater in the secondary loop. After adjusting the thermal parameters of the steam generator to ensure that the maximum deviation value is not greater than the standard temperature deviation value, the outlet regulation temperature of each heat transfer tube under test on the outlet steam tube sheet is collected, and the regulation deviation value of the outlet steam tube sheet is calculated based on the outlet regulation temperature; the standard temperature deviation model is optimized based on a certain power state of the reactor, the thermal parameters of the steam generator, the outlet regulation temperature, and the regulation deviation value.

2. The method for monitoring the outlet steam temperature of a nuclear power plant steam generator according to claim 1, characterized in that, Collect the actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet, including: A preset number of thermocouples are installed on the outlet steam tube sheet, and each thermocouple corresponds to the outlet of a heat transfer tube to be tested; The actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet is obtained based on the temperature measurement values ​​of each thermocouple.

3. The method for monitoring the outlet steam temperature of a nuclear power plant steam generator according to claim 2, characterized in that, Each heat transfer tube in the steam generator is equipped with a thermocouple at its outlet.

4. The method for monitoring the outlet steam temperature of a nuclear power plant steam generator according to claim 2, characterized in that, The steam generator includes 19 sets of heat exchange components, which are distributed at intervals along a circular plane; each set of heat exchange components includes 5 sub-units, and each sub-unit includes multiple heat transfer tubes. A thermocouple is installed at the outlet of each heat transfer tube of the heat exchange assembly located in the middle of the circular plane; In each sub-unit of each heat exchange component located at the edge of the circular plane, at least one heat transfer tube outlet is provided with a thermocouple.

5. A monitoring system for the outlet steam temperature of a nuclear power plant steam generator, characterized in that, The method for monitoring the outlet steam temperature of a nuclear power plant steam generator as described in any one of claims 1-4, wherein the monitoring system comprises: The data processing module is used to establish a temperature deviation standard model; wherein, the temperature deviation standard model includes standard values ​​of temperature deviation of the outlet steam tube sheet under various reactor power states. The monitoring module is used to collect the actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet when the reactor is at a certain power state, and to calculate the average temperature and the maximum deviation between the actual outlet temperature of each heat transfer tube under test and the average temperature based on the actual outlet temperature of each heat transfer tube under test on the outlet steam tube sheet. The control module is used to determine whether to adjust the thermal parameters of the steam generator so that the maximum deviation value is not greater than the temperature deviation standard value, based on the comparison result between the maximum deviation value and the temperature deviation standard value under a certain power state of the reactor.

6. An electronic device comprising the monitoring system for the outlet steam temperature of a nuclear power plant steam generator as described in claim 5; or, The device includes: Processor and memory; The memory is used to store executable instructions for controlling the processor to execute the method for monitoring the outlet steam temperature of a nuclear power plant steam generator according to any one of claims 1-4.

7. A computer storage medium storing computer instructions, wherein when the computer instructions in the storage medium are executed by a processor, the method for monitoring the outlet steam temperature of a nuclear power plant steam generator as described in any one of claims 1-4 is implemented.

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