Steam inlet system of steam feed pump of thermal power generating unit

Abstract

The utility model discloses a steam inlet system of a steam feed pump of a thermal power generating unit, which comprises a first steam source conveying pipeline, a second steam source conveying pipeline and a mixed steam source pipeline, and is characterized in that the input end of the first steam source conveying pipeline is connected with the output end of a first steam source providing module; the input end of the second steam source conveying pipeline is connected with the output end of the second steam source providing module, the output end of the first steam source conveying pipeline, the output end of the second steam source conveying pipeline and the input end of the mixed steam source pipeline are connected through a three-way valve, and the output end of the mixed steam source pipeline is connected with the steam feed pump turbine; the second steam source conveying pipeline is provided with a pressure adjusting valve, and the mixed steam source pipeline is provided with a first pressure detection module and a steam inlet adjusting valve. Steam is conveyed to the steam feed pump turbine through the first steam source conveying pipeline and the second steam source conveying pipeline at the same time, the valve opening angle of a pressure adjusting valve on the second steam source conveying pipeline is adjusted, and the pressure of the steam conveyed to the steam feed pump turbine through the mixed steam source pipeline is controlled.

Description

Technical Field

[0001] This utility model belongs to the field of steam-driven feedwater technology, specifically relating to the steam inlet system of the steam-driven feedwater pump for thermal power units. Background Technology

[0002] Thermal power units are generally equipped with electric feedwater pumps and steam-driven feedwater pumps. The feedwater pumps pressurize water and send it into the boiler to ensure normal water-steam circulation and maintain the normal operation of the unit. The steam-driven feedwater pump uses a small steam turbine as the prime mover and the extracted steam from the main steam turbine as the working fluid. The output is adjusted and the speed is controlled by changing the opening of the steam inlet regulating valve of the small steam turbine.

[0003] Currently, steam extracted from the main steam turbine for steam-driven feedwater pumps typically uses a low-pressure steam source (such as four-stage extraction) to deliver the steam to the feedwater pump through a low-pressure steam source pipeline. However, the pressure of the low-pressure steam source varies with load and operating conditions, making it impossible to precisely control the steam delivery volume. For example, when the pressure of the low-pressure steam source decreases for some reason (such as an increase in heating load), the inlet steam pressure of the steam-driven feedwater pump also decreases, resulting in insufficient output of the steam-driven feedwater pump, inability to maintain pump speed, seriously affecting feedwater safety, and even causing the pump to trip.

[0004] Therefore, a steam-driven feedwater pump steam inlet system for thermal power units that continuously provides high-pressure gas is needed. Utility Model Content

[0005] In view of this, the present invention provides a steam inlet system for steam-driven feedwater pumps in thermal power units, the main purpose of which is to solve the problem of low gas pressure in the current steam inlet system for steam-driven feedwater pumps in thermal power units.

[0006] To address the aforementioned problems, this application provides a steam inlet system for a steam-driven feedwater pump in a thermal power unit, comprising a first steam source delivery pipeline, a second steam source delivery pipeline, and a mixing steam source pipeline, wherein...

[0007] The input end of the first steam source delivery pipeline is connected to the output end of the first steam source supply module, the input end of the second steam source delivery pipeline is connected to the output end of the second steam source supply module, the output ends of the first steam source delivery pipeline, the output ends of the second steam source delivery pipeline and the input end of the mixed steam source pipeline are connected by a three-way valve, and the output end of the mixed steam source pipeline is connected to the steam turbine of the steam-driven feedwater pump.

[0008] The second steam source pipeline is equipped with a pressure regulating valve, and the mixed steam source pipeline is equipped with a first pressure detection module and a steam inlet regulating valve.

[0009] In one embodiment of the present invention, optionally, the first pressure detection module is disposed on the pipeline between the input end of the mixed steam source pipeline and the steam inlet regulating valve.

[0010] In one embodiment of the present invention, optionally, an electric valve is provided on the pipeline between the input end of the second steam source delivery pipeline and the pressure regulating valve, and a second pressure detection module and a first temperature detection module are provided on the pipeline between the input end of the second steam source delivery pipeline and the electric valve.

[0011] In one embodiment of the present invention, optionally, a third pressure detection module, a second temperature detection module, and a first flow detection module are provided between the output end of the second steam source delivery pipeline and the pressure regulating valve.

[0012] In one embodiment of the present invention, optionally, a third temperature detection module, a fourth pressure detection module, and a second flow detection module are sequentially arranged on the first steam source delivery pipeline.

[0013] In one embodiment of the present invention, optionally, a check valve is provided on the pipeline between the output end of the first steam source delivery pipeline and the second flow detection module.

[0014] In one embodiment of the present invention, optionally, the steam-driven feedwater pump inlet system of the thermal power unit further includes a controller, the input terminal of which is electrically connected to the output terminal of the first pressure detection module, the output terminal of the fourth pressure detection module, and the pressure regulating valve, respectively.

[0015] In one embodiment of the present invention, optionally, the sum of the pressure value detected by the fourth pressure detection module and the preset pressure value is used as the first target pressure value. When the first target pressure value is greater than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve is reduced; when the first target pressure value is less than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve is increased.

[0016] In one embodiment of the present invention, optionally, when the preset second target pressure value is greater than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve is increased; when the second target pressure value is less than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve is decreased.

[0017] The beneficial effects of this application are as follows: The steam inlet system for the steam-driven feedwater pump of the thermal power unit provided by this utility model is configured with a first steam source delivery pipeline and a second steam source delivery pipeline to simultaneously deliver steam to the steam-driven feedwater pump turbine. Based on the pressure of the first pressure detection module on the mixed steam source pipeline, the opening angle of the pressure regulating valve on the second steam source delivery pipeline is adjusted to control the steam pressure delivered to the steam-driven feedwater pump turbine by the mixed steam source pipeline, thereby ensuring a continuous supply of high-pressure steam to the steam-driven feedwater pump turbine and maintaining the speed of the steam-driven feedwater pump turbine.

[0018] The above description is merely an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this utility model more obvious and understandable, specific embodiments of this utility model are given below. Attached Figure Description

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0020] Figure 1 A schematic diagram of the steam inlet system of the steam-driven feedwater pump of a thermal power unit, which is an exemplary embodiment of this utility model;

[0021] Figure 2 Another structural connection diagram of the steam-driven feedwater pump steam inlet system of a thermal power unit, which is an exemplary embodiment of this utility model;

[0022] Figures 1-2 In the diagram, 10-First steam source delivery pipeline; 20-Second steam source delivery pipeline; 30-Mixed steam source delivery pipeline; 40-Three-way valve; 50-First steam source supply module; 60-Second steam source supply module; 70-Steam-driven feedwater pump turbine; 201-Pressure regulating valve; 301-First pressure detection module; 302-Steam inlet regulating valve; 101-Third temperature detection module; 102-Fourth pressure detection module; 103-Second flow detection module; 104-Check valve; 202-Electric valve; 203-First temperature detection module; 204-Second pressure detection module; 205-Third pressure detection module; 206-Second temperature detection module; 207-First flow detection module. Detailed Implementation

[0023] To overcome the deficiencies in the prior art, this utility model provides a steam inlet system for a steam-driven feedwater pump in a thermal power unit. To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions in the preferred embodiments of this utility model will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this utility model. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model. The embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0024] This application provides a steam inlet system for a steam-driven feedwater pump in a thermal power unit. (See also...) Figure 1 It includes a first steam source delivery pipeline 10, a second steam source delivery pipeline 20, and a mixed steam source pipeline 30, wherein,

[0025] The input end of the first steam source delivery pipeline 10 is connected to the output end of the first steam source supply module 50, the input end of the second steam source delivery pipeline 20 is connected to the output end of the second steam source supply module 60, the output ends of the first steam source delivery pipeline 10, the output ends of the second steam source delivery pipeline 20 and the input end of the mixed steam source pipeline 30 are connected through a three-way valve 40, and the output end of the mixed steam source pipeline 30 is connected to the steam-driven feedwater pump turbine 70.

[0026] The second steam source pipeline 20 is equipped with a pressure regulating valve 201, and the mixed steam source pipeline 30 is equipped with a first pressure detection module 301 and a steam inlet regulating valve 302.

[0027] Specifically, the first steam source supply module supplies steam to the first steam source delivery pipeline, and the second steam source supply module supplies steam to the second steam source delivery pipeline. The first steam source delivery pipeline supplies low-pressure steam, and the second steam source delivery pipeline supplies high-pressure steam. The first steam source supply module can provide extraction steam for the fourth stage of the main turbine, and the second steam source supply module can provide steam for the reheat cold section of the unit. After being mixed by a three-way valve, the steam from the first and second steam source delivery pipelines enters the mixed steam source pipeline, which then supplies steam to the steam-driven feedwater pump turbine. The mixed steam source pipeline is equipped with a first pressure detection module and an inlet regulating valve, while the second steam source delivery pipeline is equipped with a pressure regulating valve. The pressure regulating valve controls the pressure at the pressure measuring point corresponding to the first pressure detection module, and the inlet regulating valve controls the speed of the steam-driven feedwater pump turbine.

[0028] The speed of the steam-driven feedwater pump is closely related to the inlet steam pressure and flow rate. If the steam pressure detected by the first pressure detection module before the inlet steam regulating valve rises sharply, it may cause the steam flow and pressure entering the steam pump turbine to become uncontrollable, which in turn leads to the inability to stably control the pump speed. This will pose a serious threat to the operational safety of the entire system. Therefore, a pressure regulating valve is needed to prevent this from happening.

[0029] For example, when the gas pressure detected by the first pressure detection module is greater than the pressure setpoint P1, the system determines that the pressure is already high. If the opening of the pressure regulating valve is further increased, more steam will pass through the regulating valve, which may further increase the pressure before the steam inlet regulating valve, thus affecting the steam pump speed control. Therefore, it is forbidden to increase the opening angle of the pressure regulating valve at this time; the current valve opening should be maintained to avoid further pressure rise.

[0030] When the steam inlet regulating valve of the steam-driven feedwater pump turbine is open too wide, it indicates that a significant amount of steam has already entered the turbine. Further increasing the opening of the pressure regulating valve at this point would increase the amount of steam entering the turbine, potentially causing the pump speed to exceed safe limits. Therefore, when the steam inlet regulating valve opening exceeds a certain value, it is forbidden to increase the opening angle of the pressure regulating valve to prevent excessive steam flow and resulting in uncontrolled speed.

[0031] When the pressure detected by the first pressure detection module exceeds the higher pressure setpoint P2 (P2 > P1), it indicates that the pressure has reached a very dangerous level, which may cause serious damage to the equipment or even lead to a safety accident. At this time, the pressure regulating valve takes the most stringent protective measures, remaining completely closed, i.e., completely cutting off steam flow, to quickly reduce the steam pressure before the inlet regulating valve, protecting equipment safety and preventing uncontrollable pump speed due to excessive pressure and a series of potentially serious consequences. Through the above protection logic strategy, the pressure regulating valve can be reasonably controlled under different pressure and valve opening conditions, preventing a sharp increase in steam pressure before the inlet regulating valve due to abnormal situations, thus ensuring the safe and stable operation of the steam-driven feedwater pump and the entire system.

[0032] Compared with the prior art, the steam inlet system for the steam-driven feedwater pump of the thermal power unit provided by this utility model is equipped with a first steam source delivery pipeline and a second steam source delivery pipeline to simultaneously deliver steam to the steam-driven feedwater pump turbine. According to the pressure of the first pressure detection module on the mixed steam source pipeline, the opening angle of the pressure regulating valve on the second steam source delivery pipeline is adjusted, thereby controlling the steam pressure delivered to the steam-driven feedwater pump turbine by the mixed steam source pipeline, ensuring a continuous supply of high-pressure steam to the steam-driven feedwater pump turbine, and maintaining the speed of the steam-driven feedwater pump turbine.

[0033] In one embodiment of the present invention, see Figure 2The first pressure detection module 301 is installed on the pipeline between the input end of the mixed steam source pipeline 30 and the steam inlet regulating valve 302.

[0034] In this embodiment, a steam inlet regulating valve for the steam-driven feedwater pump turbine is installed on the mixed steam source pipeline. A first pressure detection module is installed in front of the steam inlet regulating valve. When the pressure detected by the first pressure detection module is high, it indicates that high-pressure steam will be delivered to the steam-driven feedwater pump turbine. The pressure regulating valve is used to control the pressure at the pressure measuring point corresponding to the first pressure detection module, and the steam inlet regulating valve is used to control the speed of the steam-driven feedwater pump turbine.

[0035] In one embodiment of the present invention, see Figure 2 An electric valve 202 is installed on the pipeline between the input end of the second steam source delivery pipeline 20 and the pressure regulating valve 201. A second pressure detection module 204 and a first temperature detection module 203 are installed on the pipeline between the input end of the second steam source delivery pipeline 20 and the electric valve 202.

[0036] In this embodiment, an electric valve is installed before the pressure regulating valve on the second steam source delivery pipeline. Temperature and pressure measuring points are installed before the electric valve to detect the temperature, pressure, and flow rate of the first section of the second steam source delivery pipeline. Emergency measures can be taken when the temperature, pressure, or flow rate is too high. Pressure, temperature, and flow measuring points are installed after the pressure regulating valve and before the three-way valve to detect the temperature, pressure, and flow rate of the second section of the second steam source delivery pipeline. Emergency measures can be taken when the temperature, pressure, or flow rate is too high.

[0037] When the turbine feedwater pump trips or the unit experiences a master thermal overload (MFT), the pressure regulating valve quickly and completely closes, immediately cutting off the supply of high-pressure steam and preventing steam from continuing to flow to the turbine or other related equipment. This effectively avoids a series of problems that may be caused by the continued supply of steam, such as preventing the boiler from dry-burning when the feedwater pump trips, and preventing unnecessary energy surges in the system during a unit MFT, thus protecting equipment from damage.

[0038] The electric valve, positioned before the pressure regulating valve, isolates the steam source. After the pressure regulating valve closes, the electric valve also automatically shuts off to further ensure the high-pressure steam source is completely cut off, preventing steam from entering the system through valve leaks or other possible pathways. This dual protection measure increases system safety and reliability, reducing the risk of accidents caused by incomplete steam source cutoff. By automatically shutting off the pressure regulating valve to 0% and the electric valve before the pressure regulating valve in the event of a turbine feedwater pump trip or unit MFT (Main Fuses Over-The-Air) failure, the high-pressure steam source can be quickly and effectively cut off, protecting the unit equipment, preventing major accidents, and ensuring the stability and safety of the entire unit system in emergency situations.

[0039] The opening and closing of the electric valve is linked to the command of the pressure regulating valve. The electric valve is only permitted to open or close when the pressure regulating valve is in the open position. This is because when the pressure regulating valve is fully closed, even if the electric valve opens or closes, no steam will pass through the pressure regulating valve into the downstream system, thus avoiding the risk of accidentally cutting off the high-pressure steam source in use due to misoperation of the electric valve.

[0040] This design logic interlocks the operation of the electric valve with the state of the pressure regulating valve, providing a layer of protection for the safe operation of the unit. It effectively prevents steam supply interruptions that may be caused by operators accidentally activating the electric valve, ensuring the stability and reliability of the high-pressure steam supply system.

[0041] In one embodiment of the present invention, see Figure 2 A third pressure detection module 205, a second temperature detection module 206, and a first flow detection module 207 are provided between the output end of the second steam source delivery pipeline 20 and the pressure regulating valve 201.

[0042] In this embodiment, the third pressure detection module, the second temperature detection module, and the first flow detection module are used to detect the pressure, temperature, and flow rate of the section of the second steam source delivery pipeline that is about to enter the mixed steam source pipeline. When the temperature is too high, the pressure is too high, or the flow rate is too large, emergency measures can be taken.

[0043] In one embodiment of the present invention, see Figure 2 A third temperature detection module 101, a fourth pressure detection module 102, and a second flow detection module 103 are sequentially installed on the first steam source delivery pipeline 10. A check valve 104 is installed on the pipeline between the output end of the first steam source delivery pipeline 10 and the second flow detection module 103.

[0044] In this embodiment, temperature measuring points, pressure measuring points, and flow measuring points are arranged sequentially on the first steam source delivery pipeline to detect the temperature, pressure, and flow of the first steam source delivery pipeline. When the temperature, pressure, or flow is too high, emergency measures can be taken. A check valve is installed on the first steam source delivery pipeline between the three-way valve and the flow detection module to prevent high-pressure steam from the second steam source delivery pipeline from flowing back into the first steam source delivery pipeline.

[0045] In one embodiment of the present invention, the steam-driven feedwater pump steam inlet system of the thermal power unit further includes a controller, the input terminal of which is electrically connected to the output terminal of the first pressure detection module 301, the output terminal of the fourth pressure detection module 102 and the pressure regulating valve 201 respectively.

[0046] In this embodiment, the controller adjusts the opening angle of the pressure regulating valve based on the pressure values ​​detected by the first pressure detection module and the fourth pressure detection module. Preferably, the controller is a PID controller.

[0047] In one embodiment of the present invention, the sum of the pressure value detected by the fourth pressure detection module and the preset pressure value is used as the first target pressure value. When the first target pressure value is greater than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve 201 is reduced; when the first target pressure value is less than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve 201 is increased.

[0048] In this embodiment, the steam-driven feedwater pump inlet system of the thermal power unit adopts a steam blending operation mode. The pressure value detected by the fourth pressure detection module is transmitted to the controller. The controller adds the pressure value detected by the fourth pressure detection module to a preset pressure value and uses the sum as the first target pressure value. The opening angle of the pressure regulating valve is adjusted according to the first target pressure value. When the first target pressure value is greater than the pressure value detected by the first pressure detection module, it indicates that the first steam source is supplying more steam to the mixed steam source pipeline, and the steam supply of the second steam source pipeline needs to be reduced. Therefore, the controller outputs a control command to the pressure regulating valve, causing the opening angle of the pressure regulating valve of the second steam source pipeline to decrease. When the first target pressure value is less than the pressure value detected by the first pressure detection module, it indicates that the first steam source is supplying less steam to the mixed steam source pipeline, and the steam supply of the second steam source pipeline needs to be increased. Therefore, the controller outputs a control command to the pressure regulating valve, causing the opening angle of the pressure regulating valve of the second steam source pipeline to increase. The preset pressure value can be from 0.01MPa to 0.03MPa.

[0049] In one embodiment of the present invention, when the preset second target pressure value is greater than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve 201 is increased; when the second target pressure value is less than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve 201 is decreased.

[0050] In this embodiment, a preset second target pressure value is determined based on the operating parameters of the steam-driven feedwater pump turbine. When the second target pressure value is greater than the pressure value detected by the first pressure detection module, it indicates that the steam supply to the steam-driven feedwater pump turbine is insufficient, and the steam supply volume needs to be increased. Therefore, the controller outputs a control command to the pressure regulating valve, thereby increasing the opening angle of the pressure regulating valve in the second steam supply pipeline. When the second target pressure value is less than the pressure value detected by the first pressure detection module, it indicates that the steam supply to the steam-driven feedwater pump turbine is excessive. To avoid damaging the steam-driven feedwater pump turbine, the steam supply volume needs to be reduced. Therefore, the controller outputs a control command to the pressure regulating valve, thereby decreasing the opening angle of the pressure regulating valve in the second steam supply pipeline.

[0051] In one embodiment of the present invention, the controller obtains the current main steam flow rate of the unit, substitutes the current main steam flow rate into a preset function to obtain a third target pressure value. When the third target pressure value is less than the pressure value detected by the first pressure detection module, it indicates that there is a large amount of steam supply to the steam-driven feedwater pump turbine. The controller outputs a control command to the pressure regulating valve, causing the opening angle of the pressure regulating valve of the second steam source delivery pipeline to be reduced. When the third target pressure value is greater than the pressure value detected by the first pressure detection module, it indicates that there is a small amount of steam supply to the steam-driven feedwater pump turbine. To avoid damaging the steam-driven feedwater pump turbine, it is necessary to increase the steam supply. Therefore, the controller outputs a control command to the pressure regulating valve, causing the opening angle of the pressure regulating valve of the second steam source delivery pipeline to be increased.

[0052] It should be understood that various modifications can be made to the embodiments described herein. Therefore, the above description should not be considered as limiting, but merely as an example of embodiments. Other modifications within the scope and spirit of this application will be apparent to those skilled in the art.

[0053] The accompanying drawings, which are included in and form part of this specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0054] These and other features of this application will become apparent from the following description of preferred forms of embodiments given as non-limiting examples, with reference to the accompanying drawings.

[0055] It should also be understood that although this application has been described with reference to some specific examples, those skilled in the art can certainly implement many other equivalent forms of this application.

[0056] The above and other aspects, features and advantages of this application will become more apparent when taken in conjunction with the accompanying drawings and in view of the following detailed description.

[0057] Specific embodiments of this application are described thereafter with reference to the accompanying drawings; however, it should be understood that the claimed embodiments are merely examples of this application, which can be implemented in various ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that could obscure the application. Therefore, the specific structural and functional details claimed herein are not intended to be limiting, but merely serve as the basis and representative basis for the claims to teach those skilled in the art to use this application in a variety of substantially any suitable detailed structures.

[0058] This specification may use the phrases “in one embodiment,” “in another embodiment,” “in yet another embodiment,” or “in other embodiments,” all of which may refer to one or more of the same or different embodiments according to this application.

[0059] The above embodiments are merely exemplary embodiments of this application and are not intended to limit this application. The scope of protection of this application is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to this application within its substance and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of this application.

Claims

1. A steam inlet system for a steam-driven feedwater pump in a thermal power unit, characterized in that, include: The system includes a first steam source delivery pipeline, a second steam source delivery pipeline, and a mixed steam source pipeline. The input end of the first steam source delivery pipeline is connected to the output end of the first steam source supply module, the input end of the second steam source delivery pipeline is connected to the output end of the second steam source supply module, the output ends of the first steam source delivery pipeline, the output ends of the second steam source delivery pipeline and the input end of the mixed steam source pipeline are connected by a three-way valve, and the output end of the mixed steam source pipeline is connected to the steam turbine of the steam-driven feedwater pump. The second steam source pipeline is equipped with a pressure regulating valve, and the mixed steam source pipeline is equipped with a first pressure detection module and a steam inlet regulating valve. An electric valve is installed on the pipeline between the input end of the second steam source delivery pipeline and the pressure regulating valve, and a second pressure detection module and a first temperature detection module are installed on the pipeline between the input end of the second steam source delivery pipeline and the electric valve.

2. The steam inlet system for the steam-driven feedwater pump of a thermal power unit according to claim 1, characterized in that, The first pressure detection module is installed on the pipeline between the input end of the mixed steam source pipeline and the steam inlet regulating valve.

3. The steam inlet system for the steam-driven feedwater pump of a thermal power unit according to claim 1, characterized in that, A third pressure detection module, a second temperature detection module, and a first flow detection module are provided between the output end of the second steam source delivery pipeline and the pressure regulating valve.

4. The steam inlet system for the steam-driven feedwater pump of a thermal power unit according to claim 2, characterized in that, The first steam source delivery pipeline is sequentially equipped with a third temperature detection module, a fourth pressure detection module, and a second flow detection module.

5. The steam inlet system for the steam-driven feedwater pump of a thermal power unit according to claim 4, characterized in that, A check valve is installed on the pipeline between the output end of the first steam source delivery pipeline and the second flow detection module.

6. The steam inlet system for the steam-driven feedwater pump of a thermal power unit according to claim 4, characterized in that, The steam-driven feedwater pump steam inlet system of the thermal power unit also includes a controller, the input terminal of which is electrically connected to the output terminal of the first pressure detection module, the output terminal of the fourth pressure detection module, and the pressure regulating valve, respectively.

7. The steam inlet system for the steam-driven feedwater pump of a thermal power unit according to claim 6, characterized in that, The sum of the pressure value detected by the fourth pressure detection module and the preset pressure value is used as the first target pressure value. When the first target pressure value is greater than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve is reduced; when the first target pressure value is less than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve is increased.

8. The steam inlet system for the steam-driven feedwater pump of a thermal power unit according to claim 6, characterized in that, When the preset second target pressure value is greater than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve is increased; when the second target pressure value is less than the pressure value detected by the first pressure detection module, the opening angle of the pressure regulating valve is decreased.

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