Gas turbine unit start-stop process high-pressure feed water pump system protection control method and system

Abstract

This invention discloses a protection and control method and system for a high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit, belonging to the field of intelligent control of gas turbine units. It includes a first subtraction module, a first less than comparison module, a second less than comparison module, a third less than comparison module, a first quality judgment module, a second quality judgment module, a first NOT module, a second NOT module, a third NOT module, a first AND module, a second AND module, a third AND module, a fourth AND module, a first delay module, a second delay module, a third delay module, and a first OR module. The main functions of this invention include: achieving adaptive protection throughout the start-up and shutdown process, multi-system collaborative control, improving the safety and reliability of pump unit operation, reducing the intensity of manual intervention, and adapting to the operational needs of frequent start-up and shutdown and rapid load changes of the unit.

Description

Technical Field

[0001] This invention belongs to the field of intelligent control of gas turbine units, and relates to a protection and control method and system for a high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit. Background Technology

[0002] Gas-fired combined cycle (Gas-Steam) units, due to their rapid start-up and shutdown, flexible peak shaving, and clean and efficient operation, have become the main peak-shaving power source for the power grid. These units frequently participate in deep peak shaving and cold / hot start-up and shutdown. The high-pressure feedwater pump, as the core power equipment of the waste heat boiler feedwater system, is responsible for stably supplying water to the high-pressure steam drum; its operational reliability directly determines the success rate of unit start-up and shutdown and equipment safety. Gas-fired units face typical operational challenges during start-up and shutdown: the start-up and shutdown process requires coordinated operation with the gas turbine, steam turbine, high and low pressure bypasses, and boiler feedwater system, resulting in complex control timing and interlocking logic.

[0003] Therefore, there is an urgent need for a protection and control method and system for the high-pressure feedwater pump system during the start-up and shutdown process of gas turbine units, which is highly targeted, has good coordination and outstanding self-adaptation capabilities, in order to solve problems such as low-flow cavitation, large fluctuations in operating conditions and imperfect interlocking protection, and improve the safety and intelligence level of the unit's start-up and shutdown. Summary of the Invention

[0004] To address the issue of complex control timing and interlocking logic in the start-up and shutdown process, which requires coordinated operation with the gas turbine, steam turbine, high and low pressure bypass, and boiler water supply system, the present invention aims to design a protection and control method and system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit. The main functions include: achieving adaptive protection throughout the start-up and shutdown process, multi-system coordinated control, improving the safety and reliability of pump unit operation, reducing the intensity of manual intervention, and adapting to the operational needs of frequent start-up and shutdown and rapid load changes of the unit.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: The protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of the gas turbine unit includes a first subtraction module, a first less than comparison module, a second less than comparison module, a third less than comparison module, a first quality judgment module, a second quality judgment module, a first NOT module, a second NOT module, a third NOT module, a first AND module, a second AND module, a third AND module, a fourth AND module, a first delay module, a second delay module, a third delay module, and a first OR module; The output of the first subtraction module is connected to the first less than comparison module; the output of the first quality judgment module is connected to the input of the second NOT module; the outputs of the second NOT module and the first less than comparison module are both connected to the second AND module; the output of the second AND module is connected to the fourth AND module; the output of the fourth AND module is connected to the third delay module; the output of the second quality judgment module is connected to the input of the third NOT module; the outputs of the second less than comparison module and the third NOT module are both connected to the third AND module; the output of the third AND module is connected to the first delay module; the output of the third less than comparison module is connected to the input of the second delay module; the output of the first NOT module is connected to the first AND module; the outputs of the third delay module, the first delay module, the second delay module, and the first AND module are all connected to the first OR module; the output of the first OR module is connected to the high-pressure water pump trip protection function.

[0006] A further improvement of the present invention is that it also includes: the selected values ​​of the high-pressure feedwater pump inlet pressure and the boiler low-pressure steam drum pressure are all connected to the first subtraction module.

[0007] A further improvement of the present invention is that it also includes: the inlet pressure of the high-pressure water pump is connected to the first quality judgment module.

[0008] A further improvement of the present invention is that it also includes: the high pressure water pump operating status and the high pressure water pump inlet filter differential pressure are both connected to the fourth module.

[0009] A further improvement of the present invention is that it further includes: the three selected values ​​of the boiler low-pressure steam drum water level are respectively connected to the second less-than comparison module and the second quality judgment module.

[0010] A further improvement of the present invention is that it also includes: the selected value of the lubricating oil pressure of the furnace high-pressure feedwater pump is connected to the third less-than comparison module.

[0011] A further improvement of the present invention is that it also includes: the electric gate at the inlet of the high-pressure water pump is opened to the position and connected to the first non-module.

[0012] A further improvement of the present invention is that it also includes: the high-pressure water pump operating status and the high-pressure water pump inlet electric gate being closed are both connected to the first module.

[0013] A further improvement of the present invention is that it also includes: the high-pressure water pump temperature protection action and the high-pressure water pump bearing vibration protection are both connected to the first or second module.

[0014] The protection and control methods for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit include: After the three selected values ​​of the high-pressure feedwater pump inlet pressure and the boiler low-pressure steam drum pressure are judged and calculated by the first subtraction module and the first less than comparison module, when the result is "1", and the high-pressure feedwater pump operating status is "1" and the high pressure difference of the high-pressure feedwater pump inlet filter is "1", then the output of the fourth AND module is "1", and the third delay module must also be "1". After the three-selection value of the boiler low-pressure steam drum water level is judged and calculated by the second less than comparison module, the second quality judgment module, and the third NOT module, if the result is "1", then the third AND module outputs "1", and the first delay module must also be "1". After the three selections of the lubricating oil pressure of the boiler high-pressure feedwater pump, the value must satisfy the condition that the third value is less than the comparison module and the second delay module, respectively. Then the output of the second delay module is "1". When the high-pressure water pump is in operation status "1", the high-pressure water pump inlet electric valve is closed in position "1" and the high-pressure water pump inlet electric valve is open in position "0", then the first AND module output is "1". When the high-pressure feed water pump temperature protection action is "1"; When the vibration level of the high-pressure water pump bearing is "1"; When any one of the above 6 conditions is met and the output is "1", the first OR module output is "1", triggering the high-pressure water pump trip protection function.

[0015] Compared with the prior art, the present invention has at least the following beneficial technical effects: This invention provides a protection and control system for a high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit. The system is designed with redundancy and intelligence, integrating DCS, ETS, and APS systems. Through multi-parameter linkage acquisition, adaptive algorithm adjustment, and dual hardware and software protection, it achieves deep coordination between the high-pressure feedwater pump system and the unit start-up and shutdown process, fundamentally solving technical problems such as low-flow cavitation, delayed protection response, and imperfect interlocking logic.

[0016] This invention provides a protection and control method for a high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit. Based on the core concept of "protection first, control later, strong coordination, and self-adaptation", it constructs a full-process protection and control system that includes "start-up verification - step-by-step control - shutdown protection - emergency response for special operating conditions" to address the characteristics of large fluctuations in feedwater flow, strong parameter coupling, and frequent switching of operating conditions during the start-up and shutdown phases of gas turbine units.

[0017] In summary, the protection and control method and system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit, as described in this invention, is highly targeted, has good coordination, and outstanding adaptive capabilities. It addresses issues such as low-flow cavitation, large fluctuations in operating conditions, and imperfect interlocking protection, thereby improving the safety and intelligence level of the unit's start-up and shutdown. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a protection and control system for a high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit.

[0020] Figure 2 This is a rendering of an embodiment of the present invention.

[0021] Explanation of reference numerals in the attached figures: 001. High-pressure feedwater pump operating status; 002. High differential pressure at the inlet filter of the high-pressure feedwater pump; 003. Inlet pressure of the high-pressure feedwater pump; 004. Boiler low-pressure steam drum pressure (selected from three options); 005. Boiler low-pressure steam drum water level (selected from three options); 006. Boiler high-pressure feedwater pump lubricating oil pressure (selected from three options); 007. High-pressure feedwater pump inlet electric valve closed; 008. High-pressure feedwater pump inlet electric valve open; 009. High-pressure feedwater pump temperature protection activated; 010. High-pressure feedwater pump bearing vibration high; 011. First subtraction module; 012. First less than comparison. Modules; 013, Second Less Than Comparison Module; 014, Third Less Than Comparison Module; 015, First Quality Judgment Module; 016, Second Quality Judgment Module; 017, First NOT Module; 018, Second NOT Module; 019, Third NOT Module; 020, First AND Module; 021, Second AND Module; 022, Third AND Module; 023, Fourth AND Module; 024, First Delay Module; 025, Second Delay Module; 026, Third Delay Module; 027, First OR Module; 028, High-Pressure Water Pump Trip Protection Function. Detailed Implementation

[0022] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0025] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0026] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0027] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0028] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0029] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0030] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0031] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0032] Example 1 like Figure 1 The diagram shown is a schematic diagram of a protection and control system for a high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit according to the present invention.

[0033] Specifically, it includes: high-pressure feedwater pump operating status 001, high-pressure feedwater pump inlet filter differential pressure high 002, high-pressure feedwater pump inlet pressure 003, boiler low-pressure steam drum pressure (selected value after three steps) 004, boiler low-pressure steam drum water level (selected value after three steps) 005, boiler high-pressure feedwater pump lubricating oil pressure (selected value after three steps) 006, high-pressure feedwater pump inlet electric valve closed 007, high-pressure feedwater pump inlet electric valve open 008, high-pressure feedwater pump temperature protection action 009, high-pressure feedwater pump bearing vibration high 010, first subtraction module 011, first less than Comparison module 012, Second less than comparison module 013, Third less than comparison module 014, First quality judgment module 015, Second quality judgment module 016, First NOT module 017, Second NOT module 018, Third NOT module 019, First AND module 020, Second AND module 021, Third AND module 022, Fourth AND module 023, First delay module 024, Second delay module 025, Third delay module 026, First OR module 027, High-pressure water pump trip protection function 028.

[0034] Figure 1 The schematic diagram includes the following parts: The high-pressure feedwater pump inlet pressure 003 and the selected value 004 of the boiler low-pressure steam drum pressure are both connected to the first subtraction module 011. The output of the first subtraction module 011 is connected to the first less than comparison module 012. The high-pressure feedwater pump inlet pressure 003 is sequentially connected to the first quality judgment module 015 and the second NOT module 018. The output of the second NOT module 018 and the output of the first less than comparison module 012 are both connected to the second AND module 021. The high-pressure feedwater pump operating status 001, the high-pressure feedwater pump inlet filter differential pressure 002, and the output of the second AND module 021 are all connected to the fourth AND module 023. The output of the fourth AND module 023 is connected to the third delay module 026. The selected value 005 of the boiler low-pressure steam drum water level is connected to the second less than comparison module 013. The selected value 005 of the boiler low-pressure steam drum water level is sequentially connected to the second quality judgment module 016 and the third NOT module 019. The output terminals of the first and third non-modules 019 are connected to the third AND module 022, and the output terminal of the third AND module 022 is connected to the first delay module 024; the three-selection value 006 of the high-pressure feedwater pump lubricating oil pressure is connected sequentially to the third less than comparison module 014 and the second delay module 025; the high-pressure feedwater pump inlet electric door open to position 008 is connected to the first non-module 017, and the output terminals of the high-pressure feedwater pump running status 001, the high-pressure feedwater pump inlet electric door closed to position 007, and the first non-module 017 are all connected to the first AND module 020; the output terminals of the third delay module 026, the first delay module 024, the second delay module 025, the first AND module 020, the high-pressure feedwater pump temperature protection action 009, and the high-pressure feedwater pump bearing vibration high 010 are all connected to the first OR module 027, and the output terminal of the first OR module 027 is connected to the high-pressure feedwater pump trip protection function 028.

[0035] This invention needs to be divided into the following steps: The high-pressure feedwater pump inlet pressure 003 and the boiler low-pressure steam drum pressure, after being selected by the three-way selection, are judged and calculated by the first subtraction module 011 and the first less than comparison module 012. When the result is "1", and the high-pressure feedwater pump operating status 001 is "1" and the high pressure feedwater pump inlet filter differential pressure 002 is "1", then the fourth AND module 023 outputs "1", and it is also necessary to satisfy the third delay module 026 being "1".

[0036] After the three-selection value 005 of the low-pressure steam drum water level is judged and calculated by the second less than comparison module 013, the second quality judgment module 016, and the third not module 019, when the result is "1", the output of the third AND module 022 is "1", and it is also necessary to satisfy the first delay module 024 being "1".

[0037] After the three-selection value 006 of the high-pressure feedwater pump lubricating oil pressure needs to satisfy the third less than comparison module 014 and the second delay module 025 in sequence, the output of the second delay module 025 is "1".

[0038] When the high-pressure water pump operating status 001 is "1" and the high-pressure water pump inlet electric valve is closed in place 007 is "1" and the high-pressure water pump inlet electric valve is open in place 008 is "0", then the output of the first AND module 020 is "1".

[0039] When the high-pressure water pump temperature protection action 009 is "1".

[0040] When the vibration level of the high-pressure water pump bearing is 010, it is "1".

[0041] When any one of the above 6 conditions is met and the output is "1", the first OR module 027 outputs "1", triggering the high-pressure water pump trip protection function 028.

[0042] Example 2 like Figure 2 As shown, through the implementation and application of the technology of this invention in the unit start-up, operation, and shutdown control process, the optimal flow range is dynamically locked by real-time monitoring of the correlation between flow rate and efficiency, guiding the unit to maintain a high-efficiency state throughout the start-up and stable operation phases. During the start-up phase, the flow rate is rapidly increased to the optimal range; during the operation phase, closed-loop control maintains flow stability; and during the shutdown phase, the flow rate is smoothly reduced to avoid sudden efficiency drops and equipment impact. This avoids inefficient operation under low load and energy loss at high flow rates, significantly reducing energy consumption; simultaneously, it reduces equipment wear caused by deviations from optimal operating conditions, extending the unit's lifespan.

[0043] Example 3 The protection and control system in this embodiment integrates the DCS and ETS systems of the unit, and adopts a redundant configuration of controllers and acquisition modules, including a first subtraction module 011, first to third less than comparison modules 012-014, first to second quality judgment modules 015-016, first to third NOT modules 017-019, first to fourth AND modules 020-023, first to third delay modules 024-026, and a first OR module 027. The input and output terminals of each module are logically configured according to the connection relationship of the claims. At the same time, 10 monitoring parameters, such as the high-pressure water pump operating status 001 and the inlet filter differential pressure high 002, are connected to the designated modules of the system according to the corresponding claims. The logical operation results of all modules are output as digital quantities "0" (condition not met) and "1" (condition met). The delay modules are all set to a fixed delay of 3 seconds to meet the requirements of anti-interference and signal stability judgment in industrial sites.

[0044] In this embodiment, the control system collects the field values ​​of each monitoring parameter in real time and performs logical judgments according to the six conditions described in claim 10. When any condition is met and the output is "1", the first OR module 027 outputs "1", immediately triggering the high-pressure feedwater pump trip protection function 028. The high-pressure feedwater pump performs a trip shutdown action, and at the same time, the unit DCS screen sends a trip alarm signal. The specific execution process is as follows: Condition 1: Abnormal pressure difference between inlet pressure and low-pressure steam drum triggers the test. The high-pressure feedwater pump inlet pressure 003 is the real-time value of the pressure transmitter on site, and the boiler low-pressure steam drum pressure 004 is the effective value of the three pressure transmitters on site after the three-choice logic. Both are simultaneously input into the first subtraction module 011 to complete the difference calculation. The calculation result is input into the first less than comparison module 012. When the difference is less than the set threshold, the first less than comparison module 012 outputs "1". At the same time, the high pressure feed pump inlet pressure 003 is input to the first quality judgment module 015. If the parameter signal is faulty (such as transmitter disconnection or value exceeding range), the first quality judgment module 015 outputs "1", which is then output as "0" after passing through the second non-module 018. The second non-module 018 outputs "1" only when the parameter signal is normal. The two "1" signals mentioned above are input to the second AND module 021, which outputs "1". These signals, along with the high-pressure water pump operating status 001 ("1" - pump unit in operation) and the high-pressure water pump inlet filter differential pressure 002 ("1" - filter blockage), are input to the fourth AND module 023, which outputs "1". If the signal is still "1" after a 0.263s delay by the third delay module, then this condition is met, and "1" is output.

[0045] Condition 2: Triggered by low water level in the boiler low-pressure steam drum The value 005 after the three-selection of the boiler low-pressure steam drum water level is the effective value after the three-selection logic is passed from the three water level transmitters on site. This value is simultaneously input into the second less-than comparison module 013 and the second quality judgment module 016. When the value of the low-pressure steam drum water level after three selections is less than the low water level set threshold, the second less-than comparison module 013 outputs "1"; when the water level parameter signal is normal, the second quality judgment module 016 outputs "0", and after passing through the third NOT module 019, it outputs "1". Two "1" signals are input to the third AND module 022. The third AND module 022 outputs "1". After a delay of 3 seconds by the first delay module 024, it is still "1". Therefore, this condition is met, and "1" is output.

[0046] Condition 3: Triggered by low lubricating oil pressure in the boiler high-pressure feedwater pump The value 006 after the three-selection of the lubricating oil pressure of the boiler high-pressure feedwater pump is the effective value after the three-selection logic is applied to the values ​​collected by the three oil pressure transmitters on site. This value is input to the third less-than comparison module 014. When the oil pressure is less than the low oil pressure setting threshold, the third less-than comparison module 014 outputs "1". After the signal is delayed by the second delay module 0253s, it is still "1", then the condition is met, and "1" is output.

[0047] Condition 4: Abnormal status of the entrance electric gate triggered When the high-pressure water pump operating status 001 is "1" (pump unit is running), the high-pressure water pump inlet electric door is closed in position 007 is "1" (door closed), and the high-pressure water pump inlet electric door is open in position 008 is input to the first non-module 017 and outputs "1" (i.e., the open position signal is "0", the door is not open), the three signals are input to the first AND module 020, and the first AND module 020 outputs "1", then this condition is met, and "1" is output.

[0048] Condition 5: High-pressure feed water pump temperature protection activated. When the temperature of the pump body, bearings and other parts of the high-pressure water pump exceeds the limit, the on-site temperature protection switch will activate. The high-pressure water pump temperature protection 009 will directly output "1", then this condition is met and "1" will be output.

[0049] Condition 6: High-pressure feed water pump bearing vibration triggering When the vibration value of the high-pressure water pump bearing exceeds the set threshold, the on-site vibration monitoring device will issue a high alarm signal. If the high-pressure water pump bearing vibration is high 010, it will directly output "1". If this condition is met, it will output "1".

[0050] This embodiment completed full-condition tests on a gas-steam combined cycle unit, including cold start-up, hot start-up and shutdown, and low-load peak shaving. The logic operations of each module of the control system were accurate, parameter acquisition was without delay, and the delay module effectively filtered out field interference signals. No false tripping or failure to trip occurred. When the unit operates at low load, causing an abnormal difference between the inlet pressure of the high-pressure feedwater pump and the pressure of the low-pressure steam drum, the system accurately triggers condition 1 and reliably trips after a 3-second delay to avoid pump cavitation. When the pump is started before the simulated entrance electric gate is opened, the system immediately triggers condition 4 and trips without delay, preventing hard damage to the equipment. During the start-up and shutdown of the unit, under conditions of drastic fluctuations in feedwater flow, pressure, and temperature, all modules work together to trigger a trip only when the parameters reach the protection threshold, thus achieving the core requirement of "protection first, control later".

[0051] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0052] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit, characterized in that, It includes a first subtraction module (011), a first less than comparison module (012), a second less than comparison module (013), a third less than comparison module (014), a first quality judgment module (015), a second quality judgment module (016), a first NOT module (017), a second NOT module (018), a third NOT module (019), a first AND module (020), a second AND module (021), a third AND module (022), a fourth AND module (023), a first delay module (024), a second delay module (025), a third delay module (026), and a first OR module (027); The output of the first subtraction module (011) is connected to the first less than comparison module (012). The output of the first quality judgment module (015) is connected to the input of the second NOT module (018). The outputs of the second NOT module (018) and the first less than comparison module (012) are both connected to the second AND module (021). The output of the second AND module (021) is connected to the fourth AND module (023). The output of the fourth AND module (023) is connected to the third delay module (026). The output of the second quality judgment module (016) is connected to the input of the third NOT module (019). The outputs of the second less than comparison module (013) and the third NOT module (019) are connected to the input of the second less than comparison module (015). The output terminals of block (019) are all connected to the third AND module (022), and the output terminal of the third AND module (022) is connected to the first delay module (024); the output terminal of the third less than comparison module (014) is connected to the input terminal of the second delay module (025); the output terminal of the first NOT module (017) is connected to the first AND module (020); the output terminals of the third delay module (026), the first delay module (024), the second delay module (025), and the first AND module (020) are all connected to the first OR module (027), and the output terminal of the first OR module (027) is connected to the high-pressure water pump trip protection function (028).

2. The protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit according to claim 1, characterized in that, Also includes: The high-pressure feedwater pump inlet pressure (003) and the selected value of the boiler low-pressure steam drum pressure (004) are both connected to the first subtraction module (011).

3. The protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit according to claim 2, characterized in that, Also includes: The inlet pressure of the high-pressure water pump (003) is connected to the first quality judgment module (015).

4. The protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit according to claim 3, characterized in that, Also includes: The high pressure water pump operating status (001) and the high pressure water pump inlet filter differential pressure (002) are both connected to the fourth module (023).

5. The protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit according to claim 4, characterized in that, Also includes: The three-selection value (005) of the boiler low-pressure steam drum water level is connected to the second less-than comparison module (013) and the second quality judgment module (016), respectively.

6. The protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit according to claim 5, characterized in that, Also includes: The selected value of the lubricating oil pressure of the boiler high-pressure feed water pump (006) is connected to the third less-than comparison module (014).

7. The protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit according to claim 6, characterized in that, Also includes: The high-pressure water pump inlet electric door is opened to the position (008) and connected to the first non-module (017).

8. The protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit according to claim 7, characterized in that, Also includes: The high-pressure water pump operating status (001) and the high-pressure water pump inlet electric gate closed (007) are both connected to the first module (020).

9. The protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit according to claim 8, characterized in that, Also includes: The high pressure water pump temperature protection action (009) and the high pressure water pump bearing vibration (010) are both connected to the first or module (027).

10. A protection and control method for a high-pressure feedwater pump system during the start-up and shutdown process of a gas turbine unit, characterized in that, This method is based on the protection and control system for the high-pressure feedwater pump system during the start-up and shutdown process of the gas turbine unit as described in claim 9, and includes: The high pressure feedwater pump inlet pressure (003) and the boiler low pressure steam drum pressure after three selections (004) are judged and calculated by the first subtraction module (011) and the first less than comparison module (012). When the result is "1", and the high pressure feedwater pump operating status (001) is "1" and the high pressure feedwater pump inlet filter differential pressure (002) is "1", then the fourth AND module (023) outputs "1", and the third delay module (026) needs to be "1". After the three-selection value (005) of the boiler low-pressure steam drum water level is judged and calculated by the second less than comparison module (013), the second quality judgment module (016), and the third not module (019), when the result is "1", the third AND module (022) outputs "1", and the first delay module (024) must be "1"; The selected value of the lubricating oil pressure of the boiler high pressure feed water pump (006) needs to satisfy the third less than comparison module (014) and the second delay module (025) in sequence. Then the output of the second delay module (025) is "1". When the high-pressure water pump operating status (001) is "1", the high-pressure water pump inlet electric door is closed (007) "1", and the high-pressure water pump inlet electric door is open (008) "0", then the first AND module (020) outputs "1". When the high-pressure feed water pump temperature protection action (009) is "1"; When the high-pressure water pump bearing vibration level (010) is "1"; When any one of the above 6 conditions is met and the output is "1", the first OR module (027) outputs "1", triggering the high-pressure water pump trip protection function (028).

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