Rapid load adjusting system of steam turbine generator unit

Abstract

The invention discloses a rapid load adjusting system of a steam turbine generator unit, and relates to the technical field of control of steam turbine generator units of thermal power plants. The system comprises a condenser, a circulating water input pipeline, a circulating water output pipeline, a steam turbine generator unit, a fin type heat exchanger, a cooling medium storage tank, a cooling medium conveying pipeline, an automatic temperature control flow regulating valve, a first temperature detector, a second temperature detector, a telecontrol terminal unit, a unit actual power detection mechanism and a DCS control device. The fin type heat exchanger is integrated in the circulating water input pipeline, the input end of the cooling medium conveying pipeline is connected with the output end of the cooling medium storage tank, the output end of the cooling medium conveying pipeline is connected with the fin type heat exchanger, and the automatic temperature control flow regulating valve is installed on the cooling medium conveying pipeline. Through the arrangement, the load response speed of the steam turbine generator unit under the severe working condition can be effectively improved on the premise that the complexity and the cost of the system are not obviously increased.

Description

Technical Field

[0001] This application relates to the technical field of control of steam turbine generator sets in thermal power plants, and particularly relates to a rapid load regulation system for steam turbine generator sets. Background Art

[0002] The load regulation of traditional 330MW steam turbine generator sets relies on adjusting the steam flow by the opening of high-pressure governing valves to increase or decrease the load. However, under special environmental conditions (such as high temperature in summer or poor coal quality), the traditional method cannot meet the requirements of the power grid for the load change rate. When the circulating cooling water temperature of the condenser is relatively high, the vacuum degree of the steam turbine decreases, resulting in a reduction in the work efficiency of the low-pressure cylinder and further delaying the load increase speed.

[0003] Currently, to make up for this deficiency, the industry has introduced energy storage methods such as molten salt energy storage, pumped storage, flywheel energy storage, and electric boilers to respond to and meet the requirements of the power grid for increasing the load of steam turbine generator sets. When the power grid demand for load is relatively low, the steam turbine generator sets generate more electricity, and the surplus electric energy except for the power grid demand is stored through molten salt, water collection, etc. When the power grid needs to quickly increase the load, the stored energy is released to meet the rapid load increase demand of the power grid. However, this energy storage method has the defects of high cost, complex system, high maintenance cost, and difficulty in rapid deployment. Summary of the Invention

[0004] This application aims to at least solve one of the technical problems existing in the prior art. For this purpose, this application proposes a rapid load regulation system for steam turbine generator sets, which can effectively improve the load response speed of steam turbine generator sets under harsh working conditions without significantly increasing the system complexity and cost.

[0005] This application provides a rapid load regulation system for steam turbine generator sets, including: a condenser, a circulating water input pipeline, a circulating water output pipeline, a steam turbine generator set, a finned heat exchanger, a cooling medium storage tank, a cooling medium delivery pipeline, an automatic temperature control flow regulating valve, a first temperature detector, a second temperature detector, a remote terminal unit, a unit actual power detection mechanism, and a DCS control device;

[0006] The output end of the condenser is connected to the low-pressure cylinder of the steam turbine generator set through the exhaust port of the low-pressure cylinder of the steam turbine generator set. The output end of the circulating water input pipeline is connected to the circulating water input end of the condenser. The input end of the circulating water output pipeline is connected to the circulating water output end of the condenser. The finned heat exchanger is integrated in the circulating water input pipeline. The input end of the cooling medium delivery pipeline is connected to the output end of the cooling medium storage tank. The output end of the cooling medium delivery pipeline is connected to the finned heat exchanger. The automatic temperature control flow regulating valve is installed on the cooling medium delivery pipeline. The first temperature detector is installed on the circulating water input pipeline between the finned heat exchanger and the input end of the circulating water input pipeline. The second temperature detector is installed on the circulating water input pipeline between the finned heat exchanger and the output end of the circulating water input pipeline. The actual power generation detection mechanism of the unit is installed at the outlet end of the steam turbine generator set. The DCS control device is respectively connected to the automatic temperature control flow regulating valve, the first temperature detector, the second temperature detector, the remote terminal unit, and the actual power generation detection mechanism of the unit;

[0007] The remote terminal unit is used to send an ACG load command to the DCS control device. The actual power generation detection mechanism of the unit is used to detect the actual load of the steam turbine generator set in real time and send the obtained actual load data to the DCS control device. Both the first temperature detector and the second temperature detector are used to send the temperature detection data detected in real time to the DCS control device. The DCS control device is used to judge the magnitude of the load corresponding to the ACG load command and the actual load data, and send a circulating water temperature reduction command to the automatic temperature control flow regulating valve when the ACG load is greater than the actual load. The automatic temperature control flow regulating valve increases the opening of the valve according to the circulating water temperature reduction command.

[0008] According to some embodiments of the present application, the steam turbine generator set rapid load regulation system further includes a high-pressure regulating valve. The high-pressure regulating valve is installed on the steam inlet pipeline of the high-pressure cylinder of the steam turbine generator set. The high-pressure regulating valve is connected to the DCS control device.

[0009] According to some embodiments of the present application, one end of the condenser is provided with a circulating water inlet, and the other end of the condenser is provided with a circulating water outlet. The output end of the circulating water input pipeline is connected to the condenser through the circulating water inlet. The input end of the circulating water output pipeline is connected to the condenser through the circulating water outlet.

[0010] According to some embodiments of the present application, the rapid load regulation system of the steam turbine generator set further includes a third temperature detector, which is installed on the circulating water output pipeline, and the DCS control device is connected to the third temperature detector.

[0011] According to some embodiments of the present application, the rapid load regulation system of the steam turbine generator set further includes a heat exchange device. The input end of the circulating water input pipeline is connected to the output end of the heat exchange device, and the output end of the circulating water output pipeline is connected to the input end of the heat exchange device.

[0012] According to some embodiments of the present application, the heat exchange equipment is a cooling tower or an air-cooled tower.

[0013] According to some embodiments of the present application, the finned heat exchanger is internally provided with a multi-channel spiral fin structure, and the manufacturing material of the finned heat exchanger is copper alloy or stainless steel.

[0014] According to some embodiments of the present application, the cooling medium in the cooling medium storage tank is liquid carbon dioxide or liquid nitrogen.

[0015] According to some embodiments of the present application, the rapid load regulation system of the steam turbine generator set further includes a nitrogen recovery tank, a gas discharge pipeline, a vent pipeline, a first gas flow control valve, and a second gas flow control valve. The input end of the gas discharge pipeline is connected to the gas discharge end of the finned heat exchanger, the output end of the gas discharge pipeline is connected to the input end of the nitrogen recovery tank, the input end of the vent pipeline is connected to the gas discharge pipeline, the first gas flow control valve is installed on the vent pipeline, the second gas flow control valve is installed on the gas discharge pipeline between the nitrogen recovery tank and the vent pipeline, and the DCS control device is also respectively connected to the first gas flow control valve and the second gas flow control valve.

[0016] In this application, the remote terminal unit is used to send ACG load commands to the DCS control device. The actual power generation detection mechanism of the unit is used to detect the actual load of the steam turbine generator set in real time and send the obtained actual load data to the DCS control device. Both the first temperature detector and the second temperature detector are used to send the detected temperature data in real time to the DCS control device. The DCS control device is used to judge the magnitudes of the loads corresponding to the ACG load command and the actual load data, and issue a command to open the high-pressure throttle valve wider (traditional regulation) when the ACG load is greater than the actual load. At the same time, it sends a command to reduce the circulating water temperature to the automatic temperature-controlled flow regulating valve. The automatic temperature-controlled flow regulating valve opens the valve to an appropriate opening according to the circulating water temperature reduction command to control the flow rate of the cooling medium. The cooling medium flows into the finned heat exchanger, and heat exchange occurs between the circulating water and the cooling medium in the finned heat exchanger, reducing the temperature of the circulating water transported to the condenser by 1 - 2 °C. After the circulating water temperature is reduced by 1 - 2 °C, it enters the condenser. The reduced circulating water temperature increases the vacuum degree of the condenser, can quickly increase the vacuum degree of the steam turbine generator set, increase the work efficiency of the low-pressure cylinder, increase the output of the generator, form a synergistic effect with the high-pressure throttle valve regulation, and significantly shorten the load increase time. When the load is stable, the DCS closes the temperature control regulating valve; at the same time, it has a high degree of automation, is seamlessly integrated with the unit DCS control device, realizes full-automatic regulation, and does not require additional operators. Through this setting, this application can effectively improve the load response speed of the steam turbine generator set under harsh working conditions without significantly increasing the system complexity and cost.

[0017] Additional aspects and advantages of the present application will be given in part in the following description, will become apparent in part from the following description, or will be understood through the practice of the present application. Brief Description of the Drawings

[0018] The additional aspects and advantages of the present application will become apparent and be easily understood in conjunction with the description of the embodiments with the following drawings, where:

[0019] Figure 1 is a schematic diagram of the condenser circulating cooling structure of the steam turbine generator set rapid load regulation system provided by the embodiment of the present application;

[0020] Figure 2 is a schematic diagram of the connection relationship of the DCS control device provided by the embodiment of the present application.

[0021] Reference Numerals:

[0022] Condenser 100, circulating water input pipeline 110, finned heat exchanger 111, cooling medium storage tank 112, cooling medium delivery pipeline 113, automatic temperature-controlled flow regulating valve 114, first temperature detector 115, second temperature detector 116;

[0023] Nitrogen recovery tank 120, gas discharge pipeline 121, atmosphere discharge pipeline 122, first gas flow control valve 123, second gas flow control valve 124;

[0024] Circulating water output pipeline 130, third temperature detector 131. Detailed implementation manners

[0025] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present application, and should not be construed as a limitation to the present application.

[0026] In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as up, down, front, back, left, right, etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application.

[0027] In the description of the present application, if the first and second are described only for the purpose of distinguishing technical features, it should not be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence of the indicated technical features.

[0028] In the description of the present application, unless otherwise clearly defined, terms such as setting, installation, and connection should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present application in combination with the specific content of the technical solution.

[0029] The load regulation of the traditional 330MW steam turbine generator set relies on adjusting the steam flow by the opening of the high-pressure throttle valve to increase or decrease the load. However, under special environmental conditions (such as high temperature in summer or poor quality of coal), the traditional method cannot meet the requirements of the power grid for the load change rate. When the circulating cooling water temperature of the condenser is relatively high, the vacuum degree of the steam turbine decreases, resulting in a reduction in the work efficiency of the low-pressure cylinder, further delaying the load increase speed.

[0030] At present, to make up for this deficiency, the industry has introduced energy storage methods such as molten salt energy storage, pumped hydro energy storage, flywheel energy storage, and electric boilers to respond to and meet the requirements of the power grid for increasing the load of steam turbine generator sets. When the power grid demand for load is low, the steam turbine generator sets generate more electricity, and the surplus electric energy except for the power grid demand is stored through molten salt, water collection, etc. When the power grid needs to quickly increase the load, the stored energy is released to meet the demand of the power grid for quickly increasing the load. However, this energy storage method has the defects of high cost, complex system, high maintenance cost, and difficulty in rapid deployment.

[0031] To solve the above problems, the present application proposes a rapid load regulation system for steam turbine generator sets. The following further elaborates on the embodiments of the present application with reference to the accompanying drawings.

[0032] Refer to Figures 1 to 2, an embodiment of the present application provides a fast load regulation system for a steam turbine generator set, including a condenser 100, a circulating water input pipeline 110, a circulating water output pipeline 130, a steam turbine generator set, a finned heat exchanger 111, a cooling medium storage tank 112, a cooling medium delivery pipeline 113, an automatic temperature-controlled flow regulating valve 114, a first temperature detector 115, a second temperature detector 116, a remote terminal unit, a detected mechanism for the actual power generation of the unit, and a DCS control device; the output end of the condenser 100 is connected to the low-pressure cylinder of the steam turbine generator set through the exhaust port of the low-pressure cylinder of the steam turbine generator set, the output end of the circulating water input pipeline 110 is connected to the circulating water input end of the condenser 100, the input end of the circulating water output pipeline 130 is connected to the circulating water output end of the condenser 100, the finned heat exchanger 111 is integrated in the circulating water input pipeline 110, the input end of the cooling medium delivery pipeline 113 is connected to the output end of the cooling medium storage tank 112, the output end of the cooling medium delivery pipeline 113 is connected to the finned heat exchanger 111, the automatic temperature-controlled flow regulating valve 114 is installed on the cooling medium delivery pipeline 113, the first temperature detector 115 is installed on the circulating water input pipeline 110 between the finned heat exchanger 111 and the input end of the circulating water input pipeline 110, the second temperature detector 116 is installed on the circulating water input pipeline 110 between the finned heat exchanger 111 and the output end of the circulating water input pipeline 110, the detected mechanism for the actual power generation of the unit is installed at the outlet end of the steam turbine generator set, and the DCS control device is respectively connected to the automatic temperature-controlled flow regulating valve 114, the first temperature detector 115, the second temperature detector 116, the remote terminal unit, and the detected mechanism for the actual power generation of the unit; the remote terminal unit is used to send an ACG load command to the DCS control device, the detected mechanism for the actual power generation of the unit is used to detect the actual load of the steam turbine generator set in real time and send the obtained actual load data to the DCS control device, both the first temperature detector 115 and the second temperature detector 116 are used to send the detected temperature data in real time to the DCS control device, the DCS control device is used to judge the magnitudes of the loads corresponding to the ACG load command and the actual load data and send a circulating water temperature reduction command to the automatic temperature-controlled flow regulating valve 114 when the ACG load is greater than the actual load, and the automatic temperature-controlled flow regulating valve 114 adjusts the opening degree of the valve according to the circulating water temperature reduction command.

[0033] In some embodiments, the automatic temperature-controlled flow regulating valve 114 is an electric regulating valve, and its full stroke response time does not exceed 10 seconds. The DCS control device uses a fuzzy PID algorithm to dynamically adjust the opening degree of the automatic temperature-controlled regulating valve, controls the flow rate of the cooling medium through the automatic temperature-controlled regulating valve, reduces the circulating water temperature by 1-2°C, and the rate of decrease of the circulating water temperature is 0.5-1°C per minute. Exemplarily, when the opening degree of the automatic temperature-controlled flow regulating valve 114 is adjusted to 30%, after the cooling medium flowing into the finned heat exchanger 111 exchanges heat with the circulating water, the temperature of the condensate water delivered into the condenser 100 is reduced by 1°C.

[0034] In some embodiments, a stop valve is installed on the cooling medium delivery pipeline 113, and the DCS control device is connected to the stop valve. When it is detected that the circulating water temperature drops too fast or there is a pipeline leak, the DCS control device controls the stop valve to cut off the cooling medium supply emergently.

[0035] It should be noted that AGC (Automatic Generation Control) is a technology in which the power grid dispatching system performs real-time automatic adjustment on the output (generated power) of a generator set, aiming to maintain the stability of the power grid frequency and the power balance between regions. When the power grid load demand changes, AGC will send a command (i.e., an AGC command) to the generator set, requiring the unit to quickly adjust its output to meet the power grid demand. For example, when the power grid needs to increase the load, AGC will send a "load increase command" to the steam turbine generator set; the actual power output refers to the actual electrical power output by the steam turbine generator set, that is, the power actually delivered to the power grid by the steam turbine generator set at the current moment. When the power grid needs to quickly increase the load, if the actual power output of the unit is lower than the load target value of the AGC command (i.e., there is a "load gap"), the DCS control device will quickly increase the actual power output to meet the power grid demand by adjusting the opening degree of the high-pressure regulating valve and the circulating water temperature of the condenser 100.

[0036] It should be noted that the flow rate of the cooling medium delivered to the finned heat exchanger 111 is adjusted by the automatic temperature-controlled flow regulating valve 114. The circulating water is dynamically temperature-regulated by the finned heat exchanger 111 and the cooling medium (such as cold water / refrigerant), and the vacuum degree of the condenser 100 is changed, thereby directly affecting the output of the low-pressure cylinder of the steam turbine generator set. When the grid dispatching instruction (AGC load instruction) requires an increase in load, the system reduces the circulating water temperature (increases the flow rate of the cooling medium), increases the vacuum degree of the condenser 100, improves the thermal efficiency of the steam turbine generator set, and rapidly increases the power generation. The temperature difference of the circulating water before and after the heat exchanger is monitored in real time by the first and second temperature detectors 116. Combining with the closed-loop feedback of the DCS control device, the precise adjustment of the cooling medium flow rate is ensured, avoiding energy waste caused by excessive cooling. Only the local circulating water temperature needs to be adjusted (rather than the thermal parameters of the entire system), reducing the linkage delay of multiple links such as boilers and steam turbine generator sets during the traditional load regulation process and reducing energy loss.

[0037] It should be noted that the condenser 100 is a key device in the steam turbine generator set system, which is used to condense the exhausted steam discharged from the low-pressure cylinder into condensate water and maintain a high vacuum degree in the low-pressure cylinder of the steam turbine generator set; the relationship between vacuum and load: the higher the vacuum degree (the lower the pressure), the higher the steam expansion work efficiency of the low-pressure cylinder, and the greater the output of the steam turbine generator set. The condenser 100 is connected to the exhaust port of the low-pressure cylinder of the steam turbine generator set through a pipeline. The main function of the condenser 100 is to condense the exhaust steam of the steam turbine generator set into water and maintain a vacuum state. In this way, the exhaust steam pressure of the steam turbine generator set is reduced, and the thermal efficiency is improved. The circulating water temperature decreases → the temperature difference between the steam and the cooling water in the condenser 100 increases → the steam condensation speed accelerates → the steam pressure (vacuum degree) in the condenser 100 increases, the vacuum degree increases → the exhaust steam pressure of the steam turbine generator set decreases → the effective enthalpy drop (work capacity) of the steam in the steam turbine generator set increases → the output power increases.

[0038] In some embodiments, the cooling medium storage tank 112 is connected to the finned heat exchanger 111 through a cooling medium delivery pipeline 113 made of stainless steel, and the cooling medium delivery pipeline 113 is provided with a double insulation layer.

[0039] In a possible implementation, the grid AGC command is generated by the grid dispatching center (through its energy management system, EMS) with the aim of dynamically adjusting the output of generator sets to maintain grid frequency stability and power balance. After comprehensive calculations based on grid load demand, generation plan, real-time frequency deviation, etc., the grid dispatching center issues AGC commands (usually in the form of power values, with the unit of MW) to each generator set. The grid dispatching center is connected to the power plant side through a dedicated power communication network (such as a power data network, fiber optic channel, or power carrier). The AGC command is transmitted to the remote terminal unit (RTU) of the power plant through a standard protocol (such as IEC 60870-5-104, IEC 61850, or Modbus TCP). After parsing the AGC command, the remote terminal unit sends it to the AGC interface module of the DCS control device through an in-plant industrial network (such as Ethernet, Profibus, or hardwiring). The DCS control device compares the AGC command with the current actual output power of the unit through a preset control logic (such as a PID algorithm) and generates commands to open the high-pressure throttle valve and reduce the circulating water temperature.

[0040] In some embodiments, the actual output power detection mechanism of the unit includes current transformers, voltage transformers, and power transmitters. The current transformers and voltage transformers are both installed at the outlet of the steam turbine generator set. The power transmitter is respectively connected to the current transformer, voltage transformer, and DCS control device. Three-phase current and voltage signals are collected in real time through the current transformer and voltage transformer, and the detected current and voltage data are transmitted to the power transmitter. The power transmitter calculates the actual active power according to the current and voltage data (the calculation formula is where P represents the actual active power, U represents the voltage data, I represents the current data, represents the phase difference angle between the phase voltage and phase current), and transmits the calculated actual active power to the DCS control device, that is, the actual load data sent by the actual output power detection mechanism of the unit to the DCS control device. By integrating the traditional throttle control and the newly added cooling system in the DCS, a "dual regulation" is formed, shortening the load ramp-up time. Compared with energy storage solutions (such as molten salt, pumped storage), only the circulating water system needs to be transformed, avoiding large-scale infrastructure investment. At the same time, using the existing DCS architecture, there is no need to deploy an additional independent control system, reducing the implementation difficulty.

[0041] It should be noted that by reducing the circulating water temperature by 1-2°C in this application, the vacuum degree of the steam turbine can be quickly increased, the work efficiency of the low-pressure cylinder can be increased, a synergistic effect is formed with the regulation of the high-pressure governing valve, and the load increase time can be significantly shortened; compared with the energy storage system, the investment is relatively low, the system is simple, the maintenance amount is small, and it can be quickly built and put into operation; at the same time, it ensures that the unit meets the requirements of the power grid for the load adjustment rate, avoids assessment deductions, and has the opportunity to obtain power grid reward points, creating significant economic benefits; and it is seamlessly integrated with the unit DCS system to achieve full-automatic regulation without additional operators.

[0042] In this application, the remote terminal unit is used to send an ACG load command to the DCS control device. The actual power generation detection mechanism of the unit is used to detect the actual load of the steam turbine generator set in real time and send the obtained actual load data to the DCS control device. The first temperature detector 115 and the second temperature detector 116 are both used to send the temperature detection data detected in real time to the DCS control device. The DCS control device is used to judge the size of the load corresponding to the ACG load command and the actual load data, and issue an instruction to open the high-pressure governing valve (traditional regulation) when the ACG load is greater than the actual load. At the same time, it sends a circulating water temperature reduction command to the automatic temperature control flow regulating valve 114. The automatic temperature control flow regulating valve 114 opens the valve to an appropriate opening according to the circulating water temperature reduction command to control the flow rate of the cooling medium. The cooling medium flows into the finned heat exchanger 111, and the circulating water exchanges heat with the cooling medium in the finned heat exchanger 111 to reduce the temperature of the circulating water delivered to the condenser 100 by 1-2°C. After the circulating water temperature is reduced by 1-2°C, it enters the condenser 100. The reduced circulating water temperature increases the vacuum degree of the condenser 100, can quickly increase the vacuum degree of the steam turbine generator set, increase the work efficiency of the low-pressure cylinder, increase the output of the generator, form a synergistic effect with the regulation of the high-pressure governing valve, and significantly shorten the load increase time. When the load is stable, the DCS closes the temperature control regulating valve; at the same time, it has a high degree of automation, is seamlessly integrated with the unit DCS control device, and realizes full-automatic regulation without additional operators. Through this setting in this application, the load response speed of the steam turbine generator set under harsh conditions can be effectively improved without significantly increasing the system complexity and cost.

[0043] It can be understood that the steam turbine generator set fast load regulation system further includes a high-pressure regulating valve. The high-pressure regulating valve is installed on the steam inlet pipeline of the high-pressure cylinder of the steam turbine generator set, and the high-pressure regulating valve is connected to the DCS control device.

[0044] It should be noted that the high-pressure regulating valve is a valve that controls the main steam flow rate entering the high-pressure cylinder of the steam turbine generator set. By opening or closing the opening of the high-pressure regulating valve, the amount of high-temperature and high-pressure steam entering the steam turbine generator set is changed, thereby regulating the output power (load) of the steam turbine generator set. The high-pressure regulating valve is located on the steam inlet pipeline of the high-pressure cylinder of the steam turbine generator set and directly controls the steam flow rate.

[0045] For example, when the DCS control device detects that the actual load is lower than the load target value of the AGC instruction (i.e., there is a "load gap"), the DCS control device quickly increases the actual load to meet the grid demand by adjusting the opening of the high-pressure regulating valve and the circulating water temperature of the condenser 100.

[0046] It should be noted that the high-pressure regulating valve adjusts the steam volume (directly affecting the load), and the vacuum regulation of the condenser 100 improves the efficiency of the low-pressure cylinder (indirectly assists in increasing the load). Through dual regulation (steam volume + vacuum degree), it can still quickly respond to grid demand when the temperature is high or the steam pressure is insufficient, avoiding reliance on high-cost energy storage systems.

[0047] It can be understood that a circulating water inlet is provided at one end of the condenser 100, and a circulating water outlet is provided at the other end of the condenser 100. The output end of the circulating water inlet pipeline 110 is connected to the condenser 100 through the circulating water inlet, and the input end of the circulating water output pipeline 130 is connected to the condenser 100 through the circulating water outlet.

[0048] It should be noted that by arranging the input port and the output port at both ends of the condenser 100, a countercurrent heat exchange design is formed (the circulating water flows in opposite directions to the steam), which can maximize the temperature gradient and improve the heat exchange efficiency. Compared with the parallel flow design, this layout can more efficiently remove the latent heat released by the steam condensation.

[0049] Reference Figure 1 It can be understood that the rapid load adjustment system of the steam turbine generator set also includes a third temperature detector 131 , the third temperature detector 131 is installed on the circulating water output pipeline 130 , and the DCS control device is connected to the third temperature detector 131 .

[0050] It should be noted that the third temperature detector 131 is used to detect the temperature of the circulating water in the circulating water output pipeline 130 in real time, and send the detected temperature data to the DCS control mechanism.

[0051] It is understandable that the rapid load adjustment system of the steam turbine generator set also includes a heat exchange device, the input end of the circulating water input pipeline 110 is connected to the output end of the heat exchange device, and the output end of the circulating water output pipeline 130 is connected to the input end of the heat exchange device.

[0052] It is understandable that the heat exchange hot standby is a cooling tower or an air cooling tower.

[0053] It should be noted that cooling towers (wet cooling towers) dissipate heat through evaporation by direct / indirect contact between water and air; air-cooling towers (dry cooling towers) cool the medium (such as steam or water) through air convection without evaporation.

[0054] It should be noted that the process of the circulating water is as follows: The circulating water flows out of the cooling tower / air-cooled tower, enters the condenser 100 after being pressurized by the circulating water pump, absorbs the heat of the exhaust steam of the steam turbine in the condenser 100, and the heated circulating water returns to the cooling tower / air-cooled tower for cooling. After the temperature of the circulating water drops by 1-2 °C, it enters the condenser 100. The reduced temperature of the circulating water increases the vacuum degree of the condenser 100, improves the work efficiency of the low-pressure cylinder, and increases the output of the steam turbine generator set. When the load is stable, the DCS control device closes the automatic temperature control flow regulating valve 114.

[0055] It can be understood that the finned heat exchanger 111 is internally provided with a multi-channel spiral fin structure, and the manufacturing material of the finned heat exchanger 111 is copper alloy or stainless steel.

[0056] In some embodiments, the outside of the finned heat exchanger 111 is connected to the inside of the circulating water input pipeline 110 through a flange, which is convenient for installation and maintenance.

[0057] It should be noted that the multi-channel spiral fin structure can: increase the heat transfer area: The geometric design of the spiral fins significantly expands the effective heat transfer surface area and improves the heat transfer efficiency; enhance the turbulent effect: The spiral channels force the fluid to form a swirl, break the laminar boundary layer, reduce the thermal resistance, and increase the convective heat transfer coefficient; reduce the pressure drop: The multi-channel shunt design can balance the fluid resistance and avoid the problems of too high flow velocity or too large pressure loss caused by a single channel.

[0058] In some embodiments, the finned heat exchanger 111 is made of copper alloy material. The thermal conductivity of copper alloy is much higher than that of ordinary steel, which can quickly transfer heat. At the same time, copper alloy is easy to cast or weld and is suitable for the forming of complex fin structures; In other embodiments, the finned heat exchanger 111 is made of stainless steel material. The high strength of stainless steel can withstand the impact of high-pressure circulating water and reduce the risk of structural deformation.

[0059] It can be understood that the cooling medium in the cooling medium storage tank 112 is liquid carbon dioxide or liquid nitrogen.

[0060] It should be noted that the cooling medium in the cooling medium storage tank 112 can be liquid carbon dioxide or liquid nitrogen, and the embodiments of the present application do not limit this here.

[0061] Refer to Figures 1 to 2, it can be understood that the fast load - regulating system of the steam turbine generator set further includes a nitrogen recovery tank 120, a gas discharge pipeline 121, an exhaust - to - atmosphere pipeline 122, a first gas flow control valve 123, and a second gas flow control valve 124. The input end of the gas discharge pipeline 121 is connected to the gas discharge end of the fin - type heat exchanger 111, the output end of the gas discharge pipeline 121 is connected to the input end of the nitrogen recovery tank 120, the input end of the exhaust - to - atmosphere pipeline 122 is connected to the gas discharge pipeline 121, the first gas flow control valve 123 is installed on the exhaust - to - atmosphere pipeline 122, and the second gas flow control valve 124 is installed on the gas discharge pipeline 121 between the nitrogen recovery tank 120 and the exhaust - to - atmosphere pipeline 122. The DCS control device is also respectively connected to the first gas flow control valve 123 and the second gas flow control valve 124.

[0062] It should be noted that after the liquid cooling medium (such as liquid CO2 or liquid nitrogen) absorbs heat and vaporizes in the fin - type heat exchanger 111, it enters the nitrogen recovery tank 120 through the gas discharge pipeline 121 to recover the vaporized low - temperature gas (CO2 / N2), avoiding waste of resources caused by direct discharge to the atmosphere. At the same time, it provides medium storage conditions for possible subsequent liquefaction and recirculation (through compression and cooling), reducing the operating cost. The exhaust - to - atmosphere pipeline 122 is used as an emergency backup path and is enabled in the following scenarios: when the nitrogen recovery tank 120 is full and unable to process gas in time, when the system suddenly over - pressurizes and needs to quickly relieve pressure, and when maintenance and repair require emptying the pipeline.

[0063] It should be noted that the second gas flow control valve 124 is used to regulate the gas flow entering the nitrogen recovery tank 120 to match the processing capacity of the tank body and avoid overload. The first gas flow control valve 123 serves as the final pressure - relief barrier and directly discharges gas to the atmosphere when the recovery system fails, ensuring the safety of the system.

[0064] Exemplarily, under normal conditions: the second gas flow control valve 124 is opened, and the first gas flow control valve 123 is closed to achieve medium recovery; under emergency conditions: the second gas flow control valve 124 is closed, and the first gas flow control valve 123 is opened to directly relieve pressure.

[0065] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic expressions of the above - mentioned terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0066] The above are the preferred embodiments of the present application. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present application, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present application.

[0067] Although the embodiments of the present application have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A fast load regulation system for a steam turbine generator set, characterized in that, Including: a condenser, a circulating water input pipeline, a circulating water output pipeline, a steam turbine generator set, a finned heat exchanger, a cooling medium storage tank, a cooling medium delivery pipeline, an automatic temperature-controlled flow regulating valve, a first temperature detector, a second temperature detector, a remote terminal unit, a unit actual power detection mechanism, and a DCS control device; The output end of the condenser is connected to the low-pressure cylinder of the steam turbine generator set through the exhaust port of the low-pressure cylinder of the steam turbine generator set. The output end of the circulating water input pipeline is connected to the circulating water input end of the condenser. The input end of the circulating water output pipeline is connected to the circulating water output end of the condenser. The finned heat exchanger is integrated in the circulating water input pipeline. The input end of the cooling medium delivery pipeline is connected to the output end of the cooling medium storage tank. The output end of the cooling medium delivery pipeline is connected to the finned heat exchanger. The automatic temperature-controlled flow regulating valve is installed on the cooling medium delivery pipeline. The first temperature detector is installed on the circulating water input pipeline between the finned heat exchanger and the input end of the circulating water input pipeline. The second temperature detector is installed on the circulating water input pipeline between the finned heat exchanger and the output end of the circulating water input pipeline. The unit actual power detection mechanism is installed at the outlet end of the steam turbine generator set. The DCS control device is respectively connected to the automatic temperature-controlled flow regulating valve, the first temperature detector, the second temperature detector, the remote terminal unit, and the unit actual power detection mechanism; The remote terminal unit is used to send an ACG load command to the DCS control device. The unit actual power detection mechanism is used to detect the actual load of the steam turbine generator set in real time and send the obtained actual load data to the DCS control device. Both the first temperature detector and the second temperature detector are used to send the real-time detected temperature detection data to the DCS control device. The DCS control device is used to judge the magnitude of the load corresponding to the ACG load command and the actual load data, and send a circulating water temperature reduction command to the automatic temperature-controlled flow regulating valve when the ACG load is greater than the actual load. The automatic temperature-controlled flow regulating valve adjusts the opening of the valve according to the circulating water temperature reduction command.

2. The fast load regulation system for a steam turbine generator set according to claim 1, characterized in that, The steam turbine generator set rapid load regulation system further includes a high-pressure regulating valve. The high-pressure regulating valve is installed on the steam inlet pipeline of the high-pressure cylinder of the steam turbine generator set. The high-pressure regulating valve is connected to the DCS control device.

3. The fast load regulation system for a steam turbine generator set according to claim 1, wherein One end of the condenser is provided with a circulating water input port, and the other end of the condenser is provided with a circulating water output port. The output end of the circulating water input pipeline is connected to the condenser through the circulating water input port. The input end of the circulating water output pipeline is connected to the condenser through the circulating water output port.

4. The fast load regulation system for a steam turbine generator set according to claim 3, characterized in that, The steam turbine generator set rapid load regulation system further includes a third temperature detector. The third temperature detector is installed on the circulating water output pipeline. The DCS control device is connected to the third temperature detector.

5. The fast load regulation system for a steam turbine generator set according to claim 1, characterized in that, The fast load regulation system of the steam turbine generator set further includes a heat exchange device. The input end of the circulating water input pipeline is connected to the output end of the heat exchange device, and the output end of the circulating water output pipeline is connected to the input end of the heat exchange device.

6. The fast load regulation system for a steam turbine generator set according to claim 5, wherein, The heat exchange standby is a cooling tower or an air-cooled tower.

7. The fast load regulation system for a steam turbine generator set according to claim 1, characterized in that The finned heat exchanger is internally provided with a multi-channel spiral fin structure, and the manufacturing material of the finned heat exchanger is copper alloy or stainless steel.

8. The fast load regulation system for a steam turbine generator set according to claim 1, characterized in that, The cooling medium in the cooling medium storage tank is liquid carbon dioxide or liquid nitrogen.

9. The fast load regulation system for a steam turbine generator set according to claim 1, characterized in that, The fast load regulation system of the steam turbine generator set further includes a nitrogen recovery tank, a gas discharge pipeline, an exhaust pipeline to the atmosphere, a first gas flow control valve, and a second gas flow control valve. The input end of the gas discharge pipeline is connected to the gas discharge end of the finned heat exchanger, the output end of the gas discharge pipeline is connected to the input end of the nitrogen recovery tank, the input end of the exhaust pipeline to the atmosphere is connected to the gas discharge pipeline, the first gas flow control valve is installed on the exhaust pipeline to the atmosphere, the second gas flow control valve is installed on the gas discharge pipeline between the nitrogen recovery tank and the exhaust pipeline to the atmosphere, and the DCS control device is also respectively connected to the first gas flow control valve and the second gas flow control valve.

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