Failure self-resetting method and system based on thermal power plant main throttle valve feedback

Abstract

The invention discloses a fault self-resetting method and system based on thermal power plant main throttle valve feedback, and relates to the field of thermal power plant steam turbine control system optimizing.The method comprises the steps that a main throttle valve activity test instruction is sent out; the opening degree of the main throttle valve is measured in real time, and a feedback signal is transmitted to the control system; condition judgment and set value adjustment are carried out based on the feedback signal, and first operation is carried out; the control system compares the deviation between the instruction opening degree and the actual feedback opening degree of the main throttle valve in real time, and second operation is carried out; according to the method, the situation that the main throttle valve is suddenly closed due to faults, jamming or other reasons of the main throttle valve in the activity test process of the main throttle valve of the steam turbine can be effectively avoided, large deviation of main throttle valve instructions and feedback is designed to automatically reset fault alarm signals, and operators are reminded to take measures in time. Safe and reliable operation of the steam turbine is guaranteed, and unplanned shutdown accidents of a unit caused by safe and reliable operation of the steam turbine are prevented.

Description

Technical Field

[0001] The invention relates to the field of optimization of steam turbine control systems in thermal power plants, and in particular to a method and system for self-resetting main steam valve feedback faults in thermal power plants. Background Art

[0002] During normal operation of the steam turbine in a thermal power plant, the main steam valve is always in the fully open position. During long-term operation, the valve may become stuck due to dust accumulation, corrosion, mechanical wear, etc. Regular valve activity tests can effectively prevent the valve from getting stuck and ensure that it can be opened or closed quickly and accurately when needed. Therefore, how to improve the reliability of the main steam valve activity test process and ensure that the main steam valve can automatically reset the command when a fault occurs is a topic worth studying.

[0003] At present, the reset conditions for the main steam valve activity test of the steam turbine in a thermal power plant are only used for automatic reset after a certain time has passed since the start of the test or when the steam turbine trips or the generator trips. That is, the main steam valve is reopened a certain time after the main steam valve test command is issued, and there are no other reset conditions. Once the main steam valve becomes stuck or the servo valve fails, causing the main steam valve to close too quickly, it is very easy for the main steam valve to be completely closed, causing a turbine tripping accident. Summary of the invention

[0004] In view of the above-mentioned problems, the present invention is proposed.

[0005] Therefore, the technical problem solved by the present invention is: how to increase the judgment logic of the main steam valve command and feedback to improve the reliability and safety of the main steam valve activity test.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, an embodiment of the present invention provides a method for self-resetting a main steam valve feedback fault in a thermal power plant, comprising:

[0008] Issue the main steam valve activity test command;

[0009] Real-time measurement of the main steam valve opening and transmission of feedback signals to the control system;

[0010] Perform a first operation by making a condition judgment and adjusting a set value based on the feedback signal;

[0011] The control system compares the deviation between the command opening and the actual feedback opening of the main steam valve in real time and performs the second operation.

[0012] As a preferred solution based on the self-reset method of the main steam valve feedback fault of the thermal power plant, wherein:

[0013] The issuing of the main steam valve activity test instruction comprises:

[0014] The main steam valve activity test command is generated through the operation interface, and the gradual closing of the main steam valve is achieved through the actuator.

[0015] As a preferred solution based on the self-reset method of the main steam valve feedback fault of the thermal power plant, wherein:

[0016] The real-time measurement of the main steam valve opening and transmission of the feedback signal to the control system includes:

[0017] The sensor is used to measure the opening of the main steam valve in real time; the sensor converts the measured opening into an electrical signal and transmits it to the control system through a transmission medium.

[0018] As a preferred solution based on the self-reset method of the main steam valve feedback fault of the thermal power plant, wherein:

[0019] The first operation of performing condition judgment and setting value adjustment based on the feedback signal includes:

[0020] If the opening feedback of the main steam valve is less than the preset first threshold value, the control system immediately issues a reset command to reopen the main steam valve to the fully open position.

[0021] As a preferred solution based on the self-reset method of the main steam valve feedback fault of the thermal power plant, wherein:

[0022] The control system compares the deviation between the command opening and the actual feedback opening of the main steam valve in real time, and performs the second operation including:

[0023] The control system calculates the deviation between the command opening and the actual feedback opening of the main steam valve in real time, and determines whether the deviation is within an acceptable range based on a preset second threshold value; if the deviation is greater than the preset second threshold value, it is considered that there is a significant deviation between the actual opening and the command opening of the main steam valve, triggering the second operation.

[0024] As a preferred solution based on the self-reset method of the main steam valve feedback fault of the thermal power plant, wherein:

[0025] The second operation includes:

[0026] The control system sends a command to the actuator, requiring it to reset the main steam valve to the fully open or fully closed position.

[0027] As a preferred solution based on the self-reset method of the main steam valve feedback fault of the thermal power plant, wherein:

[0028] The second operation further includes:

[0029] The control system sends out an alarm signal, including an audible alarm and a flashing screen prompt; upon receiving the alarm signal, the operating personnel immediately stops the main steam valve activity test and notifies the maintenance personnel to inspect and repair the main steam valve.

[0030] In a second aspect, an embodiment of the present invention provides a self-resetting system based on a main steam valve feedback fault in a thermal power plant, comprising:

[0031] An instruction generation module is used to issue a main steam valve activity test instruction;

[0032] The opening measurement and feedback module is used to measure the opening of the main steam valve in real time and transmit the feedback signal to the control system;

[0033] A condition judgment and set value adjustment module, used to perform condition judgment and set value adjustment based on the feedback signal to perform a first operation;

[0034] The deviation comparison and operation module is used to compare the deviation between the command opening and the actual feedback opening of the main steam valve in real time through the control system to perform the second operation.

[0035] In a third aspect, an embodiment of the present invention provides a computing device, including:

[0036] Memory and processor;

[0037] The memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions. When the one or more programs are executed by the one or more processors, the one or more processors implement the self-resetting method based on the feedback fault of the main steam valve of a thermal power plant as described in any embodiment of the present invention.

[0038] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, can implement the self-resetting method based on the feedback fault of the main steam valve of a thermal power plant.

[0039] Beneficial effects of the invention: The invention can effectively prevent the main steam valve of the steam turbine from closing suddenly due to main steam valve failure, jamming or other reasons during the activity test of the main steam valve, and is designed to automatically reset the fault alarm signal when the main steam valve command and feedback deviation are large, so as to remind the operating personnel to take measures in time, thereby ensuring the safe and reliable operation of the steam turbine and preventing the occurrence of unplanned shutdown accidents of the unit caused by this. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0041] Figure 1 It is an overall flow chart of the method for self-resetting of main steam valve feedback fault in a thermal power plant described in the first embodiment of the present invention. DETAILED DESCRIPTION

[0042] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0043] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0044] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0045] Example 1

[0046] Reference Figure 1 , which is the first embodiment of the present invention, and provides a method for self-resetting a main steam valve feedback fault in a thermal power plant, comprising:

[0047] S1: Issue the main steam valve activity test command;

[0048] S2: Real-time measurement of the main steam valve opening and transmission of feedback signals to the control system;

[0049] S3: Perform condition judgment and set value adjustment based on the feedback signal and perform the first operation;

[0050] S4: The control system compares the deviation between the command opening and the actual feedback opening of the main steam valve in real time and performs the second operation.

[0051] It should be noted that, during the operation of the steam turbine in a thermal power plant, regular main steam valve activity tests are an important measure to ensure that the main steam valve can be opened or closed quickly and accurately when needed. This embodiment adds two new reset conditions on the original basis through S1-S4 to improve the reliability and safety of the test.

[0052] Example 2

[0053] Reference Figure 1 , which is an embodiment of the present invention, provides a method for self-resetting a main steam valve feedback fault in a thermal power plant based on the previous embodiment, comprising:

[0054] In the embodiment of the present application, issuing a main valve activity test instruction in the above step S1 includes:

[0055] The operator clicks the main steam valve online activity test button on the DEH control system screen to issue a main steam valve closing command;

[0056] After receiving the command, the hydraulic servo module gradually closes the main steam valve.

[0057] In the embodiment of the present application, the real-time measurement of the opening of the main steam valve in the above step S2 and the transmission of the feedback signal to the control system include:

[0058] LVDT sensor measurement: Use LVDT (Linear Variable Differential Transformer) sensor to measure the main steam valve opening in real time. LVDT sensor is a high-precision and high-reliability displacement measurement device that can accurately reflect the actual opening of the main steam valve.

[0059] Signal conversion and transmission: The LVDT sensor converts the measured main steam valve opening into a corresponding electrical signal. This electrical signal is then transmitted to the control system via cables or other transmission media to ensure the real-time and accuracy of the data.

[0060] Control system reception and processing: After receiving the electrical signal from the LVDT sensor, the control system performs necessary signal processing and conversion to restore it to the actual opening value of the main steam valve. This step ensures that the control system can accurately grasp the current state of the main steam valve.

[0061] Real-time monitoring and feedback: The control system not only receives and processes the main steam valve opening signal, but also monitors the changes of this signal in real time. By constantly comparing the command opening and the actual feedback opening, the control system can promptly detect any deviation or abnormality, providing an important basis for subsequent control and adjustment.

[0062] It should be noted that the real-time measurement and feedback mechanism is the key link to ensure the smooth progress of the main valve activity test, which relies on the high-precision measurement of the LVDT sensor and the efficient processing of the control system.

[0063] In the embodiment of the present application, in the above step S3, condition judgment and setting value adjustment are performed based on the feedback signal, and the first operation includes:

[0064] Condition judgment: If the opening feedback of the main steam valve is less than the preset first threshold, the control system immediately issues a reset command to reopen the main steam valve to the fully open position;

[0065] The first threshold is modified in real time according to actual conditions.

[0066] In the embodiment of the present application, the initial value of the first threshold is preferably 70%, and the first threshold can be adjusted according to the actual flow characteristic curve of the main steam valve to ensure the effectiveness and safety of the test.

[0067] It should be noted that the main steam valve opening feedback is less than 70% automatic reset, which can ensure that the valve returns to the fully open position immediately after 30% of the movement. The 70% feedback position reset can verify whether the main steam valve action is normal and flexible. At the same time, according to the flow characteristic curve of the main steam valve, it can be seen that when the main steam valve is opened at a large degree, the pressure difference before and after the valve becomes smaller, and the steam flow through the valve is correspondingly smaller, which has little effect on the load change of the unit.

[0068] In another possible implementation manner, the first operation may also include real-time correction of main valve opening feedback:

[0069] When the main steam valve opening feedback is less than the preset threshold (such as 70%), the control system will not only automatically reset the main steam valve to the fully open position, but also correct the feedback signal in real time, eliminate sensor errors or drifts, and ensure the accuracy of the feedback signal.

[0070] It should be noted that this helps to improve the accuracy and reliability of the feedback signal and reduce the impact of errors on the test results.

[0071] In another possible implementation, the first operation may further include adjusting a preset action range:

[0072] According to the test requirements and the actual operation of the equipment, the action range and feedback threshold of the main steam valve are dynamically adjusted. For example, different opening feedback thresholds are set under different operating conditions to adapt to different test requirements.

[0073] It should be noted that this helps to improve the flexibility and adaptability of the test and meet the test requirements under different working conditions.

[0074] In another possible implementation, the first operation may also include real-time data recording and analysis:

[0075] When the main steam valve opening feedback is less than the preset threshold, the relevant data during the test (such as timestamp, opening change curve, etc.) are automatically recorded, and real-time analysis is performed to generate a preliminary diagnosis report.

[0076] It should be noted that this helps provide data support, facilitates subsequent fault diagnosis and performance optimization, and improves test efficiency and reliability.

[0077] In the embodiment of the present application, in the above step S4, the control system compares the deviation between the command opening and the actual feedback opening of the main steam valve in real time, and performs the second operation including:

[0078] Deviation calculation: The control system calculates the deviation between the command opening of the main steam valve and the actual feedback opening in real time. This deviation reflects the difference between the actual position of the current main steam valve and the command position.

[0079] Deviation judgment: The control system judges whether the deviation is within the acceptable range according to the preset deviation threshold. If the deviation is greater than the preset second threshold, it is considered that there is a significant deviation between the actual opening of the main steam valve and the command opening.

[0080] Triggering the second operation: When the control system detects that the deviation between the command and the feedback is greater than the preset second threshold, the second operation is triggered. The specific operations include:

[0081] Automatic reset: The control system sends a command to the actuator to reset the main steam valve to the fully open (or fully closed) position. This operation is intended to eliminate deviations and ensure that the main steam valve returns to the expected state.

[0082] Trigger alarm: At the same time, the control system will also trigger sound and light alarm signals to remind the operating personnel to pay attention to the abnormal status of the main steam valve and take corresponding measures.

[0083] Triggering of alarm signal: When the deviation is greater than the preset second threshold, the control system will send out an alarm signal, including an audible alarm and a flashing screen prompt. This helps the operator to find the problem in time and take actions, such as stopping the test and notifying the maintenance personnel to check the main steam valve.

[0084] Operator response: After receiving the alarm signal, the operator should immediately stop the main steam valve activity test and notify the maintenance personnel to inspect and repair the main steam valve to ensure the safe and reliable operation of the equipment.

[0085] In the embodiment of the present application, the initial value of the second threshold is preferably 3%.

[0086] It should be noted that the main steam valve command and feedback deviation is greater than 3% automatic reset, which can prevent the main steam valve from being stuck or the servo valve failure causing the main steam valve to close too quickly, causing the main steam valve to close completely, causing unit load fluctuations, and even causing unit shutdown accidents in severe cases. Under normal circumstances, the main steam valve feedback should be able to respond quickly to the change of the command. The deviation between the command and feedback exceeds 3%, which can indicate that the main steam valve is stuck, or the main steam valve servo valve fails, causing the valve opening to be unable to be maintained.

[0087] In another possible implementation, the control system will record the deviation value, alarm information and other relevant data in this test for subsequent analysis and reference, which helps to optimize the test process and improve the operational stability of the equipment.

[0088] In another possible implementation, the second operation may also include automatic fault diagnosis and repair:

[0089] When the control system detects that the deviation between the command and feedback is greater than the preset threshold (such as 3%), it not only triggers automatic reset and alarm, but also starts the fault diagnosis program, automatically checks possible fault points (such as sensors, servo valves, etc.), and attempts to make preliminary repairs.

[0090] It should be noted that this helps to improve the automatic maintenance capability of the equipment, reduce manual intervention, and shorten fault handling time.

[0091] In another possible implementation, the second operation may further include adjusting the operation strategy:

[0092] When the deviation is greater than the preset threshold, the control system can adjust the operating strategy according to the actual situation, such as reducing the main steam valve closing speed, limiting the maximum closing rate, etc., to reduce the impact on the unit load.

[0093] It should be noted that this helps to enhance the system's adaptive capabilities, reduce the impact of faults on unit operations, and improve operational stability.

[0094] In another possible implementation, the second operation may also include remote monitoring and intervention:

[0095] After the alarm signal is triggered, not only the on-site operating personnel are notified, but the main steam valve status can also be monitored in real time through the remote monitoring system (such as the plant-level monitoring system or external technical support team), and remote intervention or technical support can be carried out.

[0096] It should be noted that this helps to improve the response speed and efficiency of troubleshooting, especially in emergency situations, and can quickly obtain support from external experts.

[0097] Example 3

[0098] The above is a schematic scheme of the method for self-resetting the main steam valve feedback fault of a thermal power plant in this embodiment. It should be noted that the technical scheme based on the self-resetting system for the main steam valve feedback fault of a thermal power plant and the technical scheme based on the method for self-resetting the main steam valve feedback fault of a thermal power plant belong to the same concept. For the details not described in detail in the technical scheme based on the self-resetting system for the main steam valve feedback fault of a thermal power plant in this embodiment, please refer to the description of the technical scheme based on the method for self-resetting the main steam valve feedback fault of a thermal power plant.

[0099] This embodiment also provides a system based on the main steam valve feedback fault self-reset method of a thermal power plant, comprising:

[0100] An instruction generation module is used to issue a main steam valve activity test instruction;

[0101] The opening measurement and feedback module is used to measure the opening of the main steam valve in real time and transmit the feedback signal to the control system;

[0102] A condition judgment and set value adjustment module, used to perform condition judgment and set value adjustment based on the feedback signal to perform a first operation;

[0103] The deviation comparison and operation module is used to compare the deviation between the command opening and the actual feedback opening of the main steam valve in real time through the control system to perform the second operation.

[0104] This embodiment further provides a computing device, which is applicable to the case of a method for self-resetting a main steam valve feedback fault in a thermal power plant, and includes:

[0105] Memory and processor; the memory is used to store computer executable instructions, and the processor is used to execute computer executable instructions to implement the self-resetting method based on the feedback fault of the main steam valve of a thermal power plant as proposed in the above embodiment.

[0106] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, the self-resetting method based on the feedback fault of the main steam valve of a thermal power plant proposed in the above embodiment is implemented.

[0107] The storage medium proposed in this embodiment and the self-reset method based on the feedback fault of the main steam valve of a thermal power plant proposed in the above embodiment belong to the same inventive concept. The technical details not described in detail in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0108] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A self-resetting method based on the main steam valve feedback fault of a thermal power plant, characterized in that: include: Issue the main steam valve activity test command; Real-time measurement of the main steam valve opening and transmission of feedback signals to the control system; Perform a first operation by making a condition judgment and adjusting a set value based on the feedback signal; The control system compares the deviation between the command opening and the actual feedback opening of the main steam valve in real time and performs the second operation.

2. The self-resetting method based on the main steam valve feedback fault of a thermal power plant according to claim 1, characterized in that: The issuing of the main steam valve activity test instruction comprises: The main steam valve activity test command is generated through the operation interface, and the gradual closing of the main steam valve is achieved through the actuator.

3. The self-resetting method based on the main steam valve feedback fault of a thermal power plant according to claim 2, characterized in that: The real-time measurement of the main steam valve opening and transmission of the feedback signal to the control system includes: The sensor is used to measure the opening of the main steam valve in real time; the sensor converts the measured opening into an electrical signal and transmits it to the control system through a transmission medium.

4. The self-resetting method based on the main steam valve feedback fault of a thermal power plant according to claim 3 is characterized in that: The first operation of performing condition judgment and setting value adjustment based on the feedback signal includes: If the opening feedback of the main steam valve is less than the preset first threshold value, the control system immediately issues a reset command to reopen the main steam valve to the fully open position.

5. The method for self-resetting main steam valve feedback fault in a thermal power plant according to claim 4, characterized in that: The control system compares the deviation between the command opening and the actual feedback opening of the main steam valve in real time, and performs the second operation including: The control system calculates the deviation between the command opening and the actual feedback opening of the main steam valve in real time, and determines whether the deviation is within an acceptable range based on a preset second threshold value; if the deviation is greater than the preset second threshold value, it is considered that there is a significant deviation between the actual opening and the command opening of the main steam valve, triggering the second operation.

6. The self-resetting method based on the main steam valve feedback fault of a thermal power plant according to claim 5, characterized in that: The second operation includes: The control system sends a command to the actuator, requiring it to reset the main steam valve to the fully open or fully closed position.

7. The method for self-resetting main steam valve feedback fault in a thermal power plant according to claim 6, characterized in that: The second operation further includes: The control system sends out an alarm signal, including an audible alarm and a flashing screen prompt; upon receiving the alarm signal, the operating personnel immediately stops the main steam valve activity test and notifies the maintenance personnel to inspect and repair the main steam valve.

8. A system using the method for self-resetting the main steam valve feedback fault in a thermal power plant according to any one of claims 1 to 7, characterized in that: include: An instruction generation module is used to issue a main steam valve activity test instruction; The opening measurement and feedback module is used to measure the opening of the main steam valve in real time and transmit the feedback signal to the control system; A condition judgment and set value adjustment module, used to perform condition judgment and set value adjustment based on the feedback signal to perform a first operation; The deviation comparison and operation module is used to compare the deviation between the command opening and the actual feedback opening of the main steam valve in real time through the control system to perform the second operation.

9. A computing device comprising: Memory and processor; The memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions. When the computer executable instructions are executed by the processor, the steps of the self-resetting method based on the feedback fault of the main steam valve of a thermal power plant as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the method for self-resetting based on feedback fault of the main steam valve of a thermal power plant as described in any one of claims 1 to 7.

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