Control system and method for starting time of gas-steam combined cycle unit

Abstract

The invention provides a gas-steam combined cycle unit starting time control system and method.The control system comprises a gas turbine assembly, a ventilation assembly and a steam cycle assembly, and the gas turbine assembly comprises a gas compressor, a combustion chamber, a turbine and a turbine exhaust part which are sequentially connected; the turbine exhaust part is connected with a waste heat boiler drum, the ventilation assembly comprises a ventilation pipeline, the first end of the ventilation pipeline is connected with the turbine exhaust part so as to be used for introducing gas into the turbine exhaust part, and the steam circulation assembly comprises a steam turbine and a condenser which are connected. An inlet of the steam turbine is connected with an outlet of the condenser through a circulating pipeline, and part of the circulating pipeline is arranged in the waste heat boiler drum. According to the control system and method for the starting time of the gas-steam combined cycle unit, the energy consumption in the starting process is reduced, the economical efficiency of the starting process is improved, and meanwhile environmental pollution is reduced.

Description

Technical Field

[0001] This invention relates to the field of power generation equipment technology, and more specifically, to a control system and method for the start-up time of a gas-steam combined cycle unit. Background Technology

[0002] Combined cycle (CCC) power generation equipment boasts advantages such as high efficiency, flexible start-up and shutdown, and low pollutant emissions. In particular, its superior peak-shaving capability effectively enhances the stability and reliability of the power grid. However, during the startup of a CCC unit, the thermal stress of various thick-walled components necessitates a "warm-up" process. The startup process of the waste heat boiler and steam turbine is slower than that of the gas turbine. In other words, the startup time of a CCC unit is primarily limited by the bottom-cycle equipment such as the waste heat boiler and steam turbine. The gas turbine needs to wait or reduce its speed / load increase rate during the processes of waste heat boiler heating and pressurization, steam pipe warm-up, turbine acceleration and speed-up, and load increase. This process lengthens the startup time of the CCC unit, reduces its flexibility, and diminishes the economic efficiency of the startup process. Summary of the Invention

[0003] The present invention aims to at least partially solve one of the technical problems in the related art.

[0004] Therefore, embodiments of the present invention propose a control system and method for the start-up time of a gas-steam combined cycle unit. This control system reduces energy consumption during the start-up process, improves the economy of the start-up process, and reduces environmental pollution.

[0005] A control system for the start-up time of a gas-steam combined cycle unit according to an embodiment of the present invention includes: A gas turbine assembly, comprising a compressor, a combustion chamber, a turbine, and a turbine exhaust section connected in sequence, wherein the turbine exhaust section is connected to the waste heat boiler drum; A ventilation assembly, the ventilation assembly including a ventilation pipe, the first end of the ventilation pipe being connected to the turbine exhaust section for introducing gas into the turbine exhaust section; A steam circulation assembly, comprising a connected steam turbine and a condenser, wherein the inlet of the steam turbine and the outlet of the condenser are connected by a circulation pipeline, and a portion of the circulation pipeline is located inside the waste heat boiler drum.

[0006] The use of a ventilation component in the start-up time control system of the gas-steam combined cycle unit in this embodiment of the invention allows for adjustment of exhaust parameters during gas turbine start-up, reducing the limitations imposed by the waste heat boiler and steam turbine on start-up time, and effectively controlling the start-up time of the combined cycle unit. Specifically, the ventilation component introduces gas into the turbine exhaust section, increasing the gas flow rate that exchanges heat with the steam circulation pipeline, thereby reducing energy consumption during the steam circulation component start-up process and improving the economic efficiency of the start-up process.

[0007] In some embodiments, the turbine exhaust section includes a connected turbine exhaust section and an exhaust diffusion section, the turbine exhaust section is connected to the turbine, the exhaust diffusion section is connected to the waste heat boiler drum, and the first end of the ventilation pipe is connected to the turbine exhaust section.

[0008] In some embodiments, the venting line is provided with a venting control valve, and the second end of the venting line is connected to the compressor. The venting control valve is used to control the gas flow rate from the compressor to the turbine exhaust section.

[0009] In some embodiments, the gas turbine assembly further includes an intake regulating assembly connected to the compressor, the intake regulating assembly being used to regulate the gas flow rate into the compressor.

[0010] In some embodiments, the second end of the ventilation line is located on the side of the compressor adjacent to the intake regulating assembly.

[0011] In some embodiments, the second end of the ventilation pipe has an air inlet, and there are multiple air inlets arranged at intervals along the circumference of the compressor. The first end of the ventilation pipe has an air outlet, and there are multiple air outlets arranged at intervals along the circumference of the turbine exhaust section.

[0012] In some embodiments, the control system for the start-up time of the gas-steam combined cycle unit of the present invention further includes a monitoring component. The monitoring component includes a first monitoring element, which is connected to the turbine exhaust section and located downstream of the first end of the ventilation pipeline. The first monitoring element is used to monitor the gas temperature information in the turbine exhaust section, and is electrically connected to the ventilation control valve so that the ventilation control valve adjusts its opening degree according to the temperature information.

[0013] In some embodiments, the monitoring component further includes a second monitoring element connected to the turbine. The second monitoring element is used to detect the temperature information of the gas discharged from the turbine, and is electrically connected to the ventilation control valve so that the ventilation control valve adjusts its opening degree according to the temperature information.

[0014] The method for controlling the start-up time of a gas-steam combined cycle unit according to embodiments of the present invention is implemented using the control system for the start-up time of a gas-steam combined cycle unit as described in any of the above embodiments, and includes the following steps: Determine the operating conditions of the gas-steam combined cycle unit, dividing the operating conditions into normal operating condition and gas supply operating condition. In the normal operating condition, the ventilation control valve is closed, the gas flow rate of the compressor and the gas temperature discharged from the turbine are monitored, and the start-up time of the steam circulation assembly in the normal operating condition is recorded. In the ventilation working state, the ventilation control valve is in the open state. According to the gas flow rate of the compressor and the gas temperature discharged from the turbine in the normal working state, a portion of the compressor gas is drawn and introduced into the turbine exhaust section. The temperature change within the turbine exhaust section is monitored, and the opening degree of the ventilation control valve is controlled in real time based on the temperature change.

[0015] In some embodiments, during the ventilation operation, the gas flow rate extracted by the compressor per unit time does not exceed 10% of the total flow rate of the compressor, and the temperature difference between the temperature in the turbine exhaust section and the temperature of the gas discharged from the turbine is less than or equal to 50°C. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the control system for the start-up time of a gas-steam combined cycle unit according to an embodiment of the present invention.

[0017] Figure label: 1. Gas turbine assembly; 11. Compressor; 12. Combustion chamber; 13. Turbine; 14. Turbine exhaust section; 141. Turbine exhaust section; 142. Exhaust diffuser section; 15. Inlet regulating assembly; 16. Waste heat boiler drum; 17. Inlet flue; 18. Waste heat boiler chimney. 2. Ventilation assembly; 21. Ventilation piping; 22. Ventilation control valve. 3. Steam circulation components; 31. Steam turbine; 32. Condenser; 33. Circulation piping. 4. Monitoring components, 41. First monitoring element, 42. Second monitoring element. Detailed Implementation

[0018] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0019] The control system for the start-up time of a gas-steam combined cycle unit according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0020] like Figure 1 As shown, the control system for the start-up time of the gas-steam combined cycle unit in this embodiment of the invention includes: a gas turbine assembly 1, a ventilation assembly 2, and a steam cycle assembly 3.

[0021] The gas turbine assembly 1 includes a compressor 11, a combustion chamber 12, a turbine 13, and a turbine exhaust section 14 connected in sequence. The turbine exhaust section 14 is connected to the waste heat boiler drum 16. The ventilation assembly 2 includes a ventilation pipe 21, the first end of which is connected to the turbine exhaust section 14 for introducing gas into the turbine exhaust section 14. The steam circulation assembly 3 includes a steam turbine 31 and a condenser 32 connected in series. The inlet of the steam turbine 31 and the outlet of the condenser 32 are connected by a circulation pipe 33, and a portion of the circulation pipe 33 is located inside the waste heat boiler drum 16.

[0022] Specifically, such as Figure 1 As shown, the compressor 11, combustion chamber 12, turbine 13, and turbine exhaust section 14 are connected in sequence, constituting the main working process of the gas turbine. The compressor 11 is responsible for drawing in air and compressing it. The combustion chamber 12 injects fuel into the compressed air for combustion, generating high-temperature, high-pressure gas that drives the turbine 13 to rotate, thereby generating power. The turbine exhaust section 14 then directs the gas discharged from the turbine 13 to the waste heat boiler.

[0023] The first end of the ventilation line 21 is connected to the turbine exhaust section 14, allowing gas from the compressor 11 or other sources to flow into the turbine exhaust section 14, so that during the gas turbine start-up process, additional gas flow into the turbine exhaust section 14 can be controlled to adjust the exhaust parameters.

[0024] The steam turbine 31 and the condenser 32 are connected by a circulation pipe 33, part of which is located inside the waste heat boiler drum 16. In this way, the steam generated by the waste heat boiler can directly enter the steam turbine 31, while the exhaust steam from the steam turbine 31 enters the condenser 32 for condensation, completing the conversion of thermal energy into mechanical energy.

[0025] Understandably, by using the ventilation pipe 21 to introduce low-temperature gas from the outside into the turbine exhaust section 14 of the turbine 13, the low-temperature gas can be mixed with the high-temperature exhaust gas after the gas turbine assembly 1 is started, thereby increasing the gas flow rate into the waste heat boiler drum 16 and ensuring that the gas flow rate and temperature entering the waste heat boiler drum 16 meet the "warm-up" requirements of the waste heat boiler drum 16 and steam equipment such as the steam turbine.

[0026] In addition, the flow rate of gas entering the turbine exhaust section 14 can be controlled by controlling the opening of the ventilation pipe 21, thereby adjusting the flow rate and temperature of the mixed gas in real time.

[0027] In other words, the use of the ventilation component 2 in the control system for the start-up time of the gas-steam combined cycle unit in this embodiment of the invention can adjust the exhaust parameters during the gas turbine start-up process, reducing the limitations imposed by the waste heat boiler and steam turbine 31 on the start-up time, thus effectively controlling the start-up time of the combined cycle unit. Specifically, by using the ventilation component 2 to introduce gas into the turbine exhaust section 14, the flow rate of the gas exchanging heat with the steam circulation pipeline 33 is increased, thereby reducing the energy consumption during the start-up process of the steam circulation component 3 and improving the economic efficiency of the start-up process.

[0028] It should be noted that the waste heat boiler drum 16 is connected to the turbine exhaust section 14 through the inlet flue 17, and the outlet of the waste heat boiler drum 16 is connected to the waste heat boiler chimney 18 for discharging the flue gas after heat exchange.

[0029] In some embodiments, the turbine exhaust section 14 includes a connected turbine exhaust section 141 and an exhaust diffusion section 142. The turbine exhaust section 141 is connected to the turbine 13, the exhaust diffusion section 142 is connected to the waste heat boiler drum 16, and the first end of the ventilation pipe 21 is connected to the turbine exhaust section 141.

[0030] Specifically, such as Figure 1 As shown, the turbine exhaust section 14 consists of two parts: a turbine exhaust section 141 and an exhaust diffuser section 142. The turbine exhaust section 141 is directly connected to the turbine 13 and receives the high-temperature gas discharged from the turbine 13. The exhaust diffuser section 142 is connected to the waste heat boiler drum 16, and its function is to gradually reduce the gas flow rate while allowing for more complete heat exchange before entering the waste heat boiler. The first end of the ventilation pipe 21 is connected to the turbine exhaust section 141, which allows additional gas to be introduced into the turbine exhaust section 141 through the ventilation pipe 21 during gas turbine startup. This allows the gas flow rate and temperature of the turbine exhaust section 141 to be adjusted as needed to optimize the operating parameters of the gas turbine.

[0031] Understandably, by introducing gas into the turbine exhaust section 141, the exhaust temperature and flow rate of the gas turbine can be effectively controlled, which helps to reduce the risk of thermal stress and vibration during startup. At the same time, it can also reach the temperature and pressure conditions required by the waste heat boiler more quickly, shortening the startup time.

[0032] In some embodiments, the ventilation line 21 is provided with a ventilation control valve 22, and the second end of the ventilation line 21 is connected to the compressor 11. The ventilation control valve 22 is used to control the gas flow rate from the compressor 11 to the turbine exhaust section 141.

[0033] Specifically, such as Figure 1 As shown, a ventilation control valve 22 is provided in the ventilation line 21. The main function of the ventilation control valve 22 is to control the gas flow from the compressor 11 to the turbine exhaust section 141, thereby regulating the gas flow and temperature in the turbine exhaust section 141. The second end of the ventilation line 21 is connected to the compressor 11, so that a portion of the compressed air in the compressor 11 can be guided to the turbine exhaust section 141, instead of being used entirely for the combustion process.

[0034] Understandably, the gas flow rate to the turbine exhaust section 141 can be precisely controlled by adjusting the opening of the ventilation control valve 22. During gas turbine startup, this control mechanism can be used to regulate the exhaust temperature to match the heat demand of the waste heat boiler. Precise flow control helps reduce energy loss during startup and also reduces the thermal stress on the gas turbine itself, improving startup reliability and safety.

[0035] Furthermore, the ventilation control valve 22 is primarily opened during the gas turbine start-up and shutdown process. By venting a portion of the interstage air from the compressor 11 to the turbine exhaust section 141, it reduces the risk of compressor surge in the compressor 11, ensuring the safe and stable operation of the unit. During the start-up of the combined cycle unit, by changing the operating mode of the ventilation control valve 22, the venting flow rate of the turbine exhaust section 141 is increased, the flow rate entering the combustion chamber 12 for combustion is reduced, the combustion temperature is increased, the combustion efficiency is improved, and the pollutant emissions from the combustion chamber 12 are reduced.

[0036] In some embodiments, the gas turbine assembly 1 further includes an intake regulating assembly 15, which is connected to the compressor 11 and is used to regulate the gas flow rate into the compressor 11.

[0037] Specifically, such as Figure 1 As shown, the intake regulating assembly 15 is connected to the compressor 11 and can regulate the airflow entering the compressor 11 according to the operating requirements of the gas turbine. The regulating assembly includes adjustable structures, such as variable intake guide vanes, adjustable intake blades, or other flow control mechanisms.

[0038] Understandably, the intake regulating component 15 allows for precise control of the gas flow rate entering the compressor 11, which is particularly important during startup. Initially, the gas turbine may require a lower intake volume to prevent excessive wear or vibration, but once a certain temperature and pressure are reached, the intake volume can be gradually increased to meet operational needs.

[0039] During startup, the intake regulating component 15 can dynamically adjust the intake volume according to the real-time operating parameters of the gas turbine to ensure a smooth transition during startup and reduce the impact on unit components. This allows the gas turbine to better adapt to different operating conditions, maintaining efficient, safe, and environmentally friendly operation both during startup and normal operation.

[0040] In some embodiments, the second end of the ventilation line 21 is located on the side of the compressor 11 adjacent to the intake regulating assembly 15.

[0041] It is understandable that, such as Figure 1 As shown, the second end of the ventilation pipe 21 is located on the side of the compressor 11 adjacent to the intake regulating assembly 15, meaning that the gas drawn from the compressor 11 can directly enter the ventilation pipe 21 after being regulated by the intake regulating assembly 15. This simplifies the pipe layout and reduces airflow resistance.

[0042] In other words, because the second end of the ventilation pipe 21 is close to the intake regulating component 15, it can respond quickly when the intake regulating component 15 adjusts the intake volume, so that the gas flow rate and pressure drawn from the compressor 11 can be adjusted in a timely manner. This improves the responsiveness of the gas turbine to intake regulation, enabling the gas turbine to adapt to changes in external load more quickly and improving the flexibility of the unit.

[0043] In some embodiments, the second end of the ventilation duct 21 has an air inlet, and there are multiple air inlets, which are arranged at intervals along the circumference of the compressor 11. The first end of the ventilation duct 21 has an air outlet, and there are multiple air outlets, which are arranged at intervals along the circumference of the turbine exhaust section 141.

[0044] Understandably, the second end of the vent line 21 has multiple air inlets, which are arranged circumferentially around the compressor 11. This design allows gas to be drawn from multiple locations on the compressor 11 to achieve a uniform distribution of the gas flowing into the turbine exhaust section 141. The first end of the vent line 21 has multiple air outlets, which are arranged circumferentially around the turbine exhaust section 141. This design allows gas to be uniformly discharged from multiple locations on the turbine exhaust section 141, which helps to improve heat exchange efficiency.

[0045] In other words, the design of multiple air inlets helps to avoid excessive pressure loss when the gas flows through the ventilation pipe 21, while ensuring uniform gas distribution in the turbine exhaust section 141 and reducing the possibility of local overheating or undercooling. The design of multiple air outlets helps to ensure uniform gas distribution in the turbine exhaust section 141, reduces local impact of airflow on the turbine exhaust section 141, and also benefits the heat exchange efficiency of the waste heat boiler.

[0046] In some embodiments, the control system for the start-up time of the gas-steam combined cycle unit of the present invention further includes a monitoring component 4. The monitoring component 4 includes a first monitoring element 41, which is connected to the turbine exhaust section 141 and located downstream of the first end of the ventilation pipeline 21. The first monitoring element 41 is used to monitor the gas temperature information in the turbine exhaust section 141, and is electrically connected to the ventilation control valve 22 so that the ventilation control valve 22 adjusts the opening degree according to the temperature information.

[0047] Understandably, the first monitoring element 41 of the monitoring component 4 is connected to the turbine exhaust section 141 and is located downstream of the first end of the ventilation pipeline 21. The first monitoring element 41 is used to monitor the gas temperature information within the turbine exhaust section 141. By setting a temperature monitoring point in the turbine exhaust section 141, the temperature data of the exhaust section can be obtained in real time. This is crucial for controlling the opening of the ventilation control valve 22, as the exhaust temperature directly affects the heat exchange efficiency of the waste heat boiler and the operational safety of the entire combined cycle unit.

[0048] In other words, the first monitoring element 41 not only monitors the temperature but is also electrically connected to the ventilation control valve 22, allowing the temperature monitoring data to be directly used to control the opening of the ventilation control valve 22. This design enables real-time feedback control of temperature data, allowing the ventilation control valve 22 to dynamically adjust its opening based on the real-time temperature of the turbine exhaust section 141, thereby maintaining the exhaust temperature within a safe range and optimizing the heat exchange process of the waste heat boiler.

[0049] In some embodiments, the monitoring component 4 further includes a second monitoring element 42, which is connected to the turbine 13. The second monitoring element 42 is used to detect the temperature information of the gas discharged from the turbine 13, and is electrically connected to the ventilation control valve 22 so that the ventilation control valve 22 adjusts the opening degree according to the temperature information.

[0050] Understandably, the second monitoring element 42 is located at turbine 13 and is used to detect the temperature of the gas discharged from turbine 13. This arrangement ensures that the main exhaust temperature of the gas turbine can be monitored in real time, which is crucial for controlling the opening of the ventilation control valve 22. By monitoring the gas temperature discharged from turbine 13, a more comprehensive understanding of the gas turbine's operating status can be obtained, providing more accurate data support for the adjustment of the ventilation control valve 22.

[0051] The second monitoring element 42 is electrically connected to the ventilation control valve 22, meaning that the gas temperature information discharged from the turbine 13 can be directly used to control the opening of the ventilation control valve 22. This achieves real-time feedback control of temperature data, allowing the ventilation control valve 22 to dynamically adjust its opening based on the gas temperature discharged from the turbine 13, thereby maintaining the exhaust temperature within a safe range and optimizing the heat exchange process of the waste heat boiler.

[0052] In other words, the overall performance of the gas-steam combined cycle unit is improved by introducing monitoring component 4. Real-time feedback and control of temperature monitoring data help maintain the unit in optimal operating condition, improve thermal efficiency, reduce emissions, and enhance the unit's responsiveness and flexibility. It also benefits the unit's operating efficiency, has a positive impact on the stability and reliability of the power grid, and meets environmental protection and energy conservation requirements.

[0053] The following describes a method for controlling the start-up time of a gas-steam combined cycle unit according to an embodiment of the present invention.

[0054] The method for controlling the start-up time of a gas-steam combined cycle unit according to an embodiment of the present invention is implemented using the control system for the start-up time of a gas-steam combined cycle unit as described in any of the above embodiments, and includes the following steps: The operating conditions of the gas-steam combined cycle unit are determined and divided into normal operation and ventilated operation. Under normal operation, the ventilated control valve 22 remains closed, and the system operates according to the conventional process. This division of operating conditions facilitates refined management of unit performance under different operating conditions, ensuring that the unit operates at maximum efficiency under normal operation, while allowing for flexible adjustment through the ventilated operation state when rapid start-up is required.

[0055] Under normal operating conditions, the ventilation control valve 22 is closed, the gas flow rate of the compressor 11 and the gas temperature discharged from the turbine 13 are monitored, and the start-up time of the steam circulation assembly 3 under normal operating conditions is recorded.

[0056] Under normal operating conditions, it is understandable that monitoring the gas flow rate of compressor 11 and the gas temperature discharged from turbine 13, as well as recording the start-up time of steam cycle assembly 3 under normal operating conditions, is crucial for subsequent start-up time optimization and control. By monitoring and recording operating data under normal operating conditions, a benchmark can be provided for parameter adjustments under ventilated operating conditions, ensuring effective control of the unit's start-up time under ventilated operating conditions.

[0057] In the ventilation operation state, the ventilation control valve 22 is in the open state. Based on the gas flow rate of the compressor 11 in normal operation and the gas temperature discharged from the turbine 13, a portion of the gas from the compressor 11 is drawn and introduced into the turbine exhaust section 141.

[0058] Understandably, during the ventilation operation, the ventilation control valve 22 opens, and based on the gas flow rate of the compressor 11 and the gas temperature discharged from the turbine 13 under normal operating conditions, a portion of the gas from the compressor 11 is drawn and introduced into the turbine exhaust section 141. This step helps to quickly raise the temperature of the turbine exhaust section 141, accelerating the preheating process of the waste heat boiler. By introducing additional gas flow during the ventilation operation, the start-up time of the waste heat boiler and steam circulation equipment can be significantly shortened, improving the unit's start-up speed and flexibility.

[0059] Monitor the temperature change within the turbine exhaust section 141 and control the opening of the ventilation control valve 22 in real time based on the temperature change.

[0060] Understandably, monitoring temperature changes within the turbine exhaust section 141 and adjusting the opening of the ventilation control valve 22 in real time based on these changes ensures that the temperature of the turbine exhaust section 141 reaches the required level quickly and smoothly, while preventing excessively high temperatures from damaging unit components. Real-time control of the ventilation control valve 22 enables refined management of the unit startup process, ensuring both speed and safety during startup, and improving the unit's responsiveness to grid demands.

[0061] In some embodiments, during the ventilation operation, the gas flow rate extracted by the compressor 11 does not exceed 10% of the total flow rate of the compressor 11 per unit time, and the temperature difference between the temperature in the turbine exhaust section 141 and the gas temperature discharged from the turbine 13 is less than or equal to 50°C.

[0062] Understandably, during ventilation operation, the gas flow rate extracted by compressor 11 per unit time shall not exceed 10% of the total flow rate of compressor 11. This limitation aims to ensure that the normal operation of compressor 11 is not affected by ventilation operation, and to avoid affecting the efficiency and stability of compressor 11 due to excessive gas extraction. By limiting the proportion of extracted gas, the stable operation of compressor 11 can be maintained, while ensuring that the exhaust parameters of the gas turbine still meet the requirements of the waste heat boiler during ventilation operation, and preventing the performance degradation of the gas turbine due to excessive extraction.

[0063] Under ventilation operation, the temperature difference between the turbine exhaust section 141 and the gas temperature discharged from the turbine 13 is less than or equal to 50°C. This limitation helps control the rate of temperature rise in the turbine exhaust section 141, preventing excessively rapid temperature changes from damaging the turbine exhaust section 141 and the waste heat boiler. By limiting the temperature difference, it is ensured that the temperature change within the turbine exhaust section 141 is within a controllable range, reducing the generation of thermal stress, protecting unit components from damage, and also improving the heat exchange efficiency of the waste heat boiler.

[0064] In other words, by limiting the gas flow rate extracted by compressor 11 and controlling the temperature difference, the parameters of the ventilation operation are precisely managed, ensuring the safety and stability of the unit while accelerating the start-up process, and also optimizing the heat exchange efficiency of the waste heat boiler. Therefore, while ensuring the normal operation of the gas turbine, the temperature of the turbine exhaust section 141 can be rapidly increased, accelerating the preheating process of the waste heat boiler, thereby effectively shortening the start-up time of the combined cycle unit and improving the unit's economy and grid response capability.

[0065] 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 are not intended to 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.

[0066] 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 technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0067] 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 connection that allows communication between them; 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, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0068] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0069] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0070] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A control system for the start-up time of a gas-steam combined cycle unit, characterized in that, include: A gas turbine assembly, comprising a compressor, a combustion chamber, a turbine, and a turbine exhaust section connected in sequence, wherein the turbine exhaust section is connected to the waste heat boiler drum; A ventilation assembly, the ventilation assembly including a ventilation pipe, the first end of the ventilation pipe being connected to the turbine exhaust section for introducing gas into the turbine exhaust section; A steam circulation assembly, comprising a connected steam turbine and a condenser, wherein the inlet of the steam turbine and the outlet of the condenser are connected by a circulation pipeline, and a portion of the circulation pipeline is located inside the waste heat boiler drum.

2. The control system for the start-up time of a gas-steam combined cycle unit according to claim 1, characterized in that, The turbine exhaust section includes a connected turbine exhaust section and an exhaust diffusion section. The turbine exhaust section is connected to the turbine, and the exhaust diffusion section is connected to the waste heat boiler drum. The first end of the ventilation pipe is connected to the turbine exhaust section.

3. The control system for the start-up time of a gas-steam combined cycle unit according to claim 2, characterized in that, The ventilation pipeline is equipped with a ventilation control valve. The second end of the ventilation pipeline is connected to the compressor. The ventilation control valve is used to control the gas flow rate from the compressor to the turbine exhaust section.

4. The control system for the start-up time of a gas-steam combined cycle unit according to claim 3, characterized in that, The gas turbine assembly also includes an intake regulating component connected to the compressor, which is used to regulate the gas flow rate into the compressor.

5. The control system for the start-up time of a gas-steam combined cycle unit according to claim 4, characterized in that, The second end of the ventilation line is located on the side of the compressor adjacent to the intake regulating assembly.

6. The control system for the start-up time of a gas-steam combined cycle unit according to claim 5, characterized in that, The second end of the ventilation pipe has an air inlet, and there are multiple air inlets, which are arranged at intervals along the circumference of the compressor. The first end of the ventilation pipe has an air outlet, and there are multiple air outlets, which are arranged at intervals along the circumference of the turbine exhaust section.

7. The control system for the start-up time of a gas-steam combined cycle unit according to any one of claims 3-6, characterized in that, It also includes a monitoring component, which includes a first monitoring element connected to the turbine exhaust section and located downstream of the first end of the ventilation pipeline. The first monitoring element is used to monitor the gas temperature information in the turbine exhaust section, and is electrically connected to the ventilation control valve so that the ventilation control valve adjusts its opening degree according to the temperature information.

8. The control system for the start-up time of a gas-steam combined cycle unit according to claim 7, characterized in that, The monitoring component further includes a second monitoring element connected to the turbine. The second monitoring element is used to detect the temperature information of the gas discharged from the turbine, and is electrically connected to the ventilation control valve so that the ventilation control valve adjusts its opening degree according to the temperature information.

9. A method for controlling the start-up time of a gas-steam combined cycle unit, wherein the method for controlling the start-up time of the gas-steam combined cycle unit is implemented using the control system for the start-up time of the gas-steam combined cycle unit as described in any one of claims 1-8, characterized in that, Includes the following steps: Determine the operating conditions of the gas-steam combined cycle unit, dividing the operating conditions into normal operating condition and gas supply operating condition. In the normal operating condition, the ventilation control valve is closed, the gas flow rate of the compressor and the gas temperature discharged from the turbine are monitored, and the start-up time of the steam circulation assembly in the normal operating condition is recorded. In the ventilation working state, the ventilation control valve is in the open state. According to the gas flow rate of the compressor and the gas temperature discharged from the turbine in the normal working state, a portion of the compressor gas is drawn and introduced into the turbine exhaust section. The temperature change within the turbine exhaust section is monitored, and the opening degree of the ventilation control valve is controlled in real time based on the temperature change.

10. The method for controlling the start-up time of a gas-steam combined cycle unit according to claim 9, characterized in that, In the ventilation operation state, the gas flow rate extracted by the compressor does not exceed 10% of the total flow rate of the compressor per unit time, and the temperature difference between the exhaust section of the turbine and the exhaust gas temperature is less than or equal to 50°C.

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