Water supply temperature feedforward compensation control method based on fused salt heat storage and related equipment

Abstract

The application belongs to the technical field of control of photo-thermal power turbine, and discloses a feed water temperature feedforward compensation control method based on molten salt heat storage and related equipment; wherein the feed water temperature feedforward compensation control method based on molten salt heat storage comprises inputting current operation parameters into a pre-established feed water temperature prediction model, outputting a feed water temperature drop amplitude prediction value through the feed water temperature prediction model, and the feed water temperature prediction model comprises a high-pressure heater heat balance principle; when a cylinder cutting instruction is received, the feed water temperature drop amplitude prediction value is used to compensate for a feed water heat gap caused by disappearance of high-pressure heater steam extraction, so as to realize feed water temperature feedforward compensation; the application can compensate for the heat gap caused by disappearance of high-pressure heater steam extraction in real time, and solves the problem that the prior art can only passively respond through feedback regulation after actual drop of the feed water temperature, and cannot predict and compensate for the heat gap in advance.

Description

Technical Field

[0001] This invention relates to the field of solar thermal power generation turbine control technology, specifically to a feedforward compensation control method and related equipment for feedwater temperature based on molten salt thermal storage. Background Technology

[0002] With the advancement of the "dual carbon" target and the deepening of the construction of new power systems, the demand for flexible peak-shaving capabilities in the power grid is becoming increasingly urgent. Concentrated solar power (CSP), with its molten salt thermal storage system, can achieve 24-hour continuous power generation and deep peak-shaving, becoming an important regulating power source in the new energy power system. Under deep peak-shaving conditions, zero-output operation of the turbine's high-pressure cylinder (cylinder cut-off) is an effective means to further reduce the unit's minimum technical output. During cylinder cut-off, the main steam enters the reheater after being de-cooled and depressurized by the high-pressure bypass valve; the high-pressure cylinder does not perform work, and the unit's output is mainly provided by the intermediate-pressure and low-pressure cylinders.

[0003] Existing technologies include solutions that regulate feedwater temperature by connecting a bypass in parallel with the high-pressure heater. However, this solution primarily addresses the molten salt solidification problem caused by excessively low feedwater temperature under low-load conditions, without considering the sudden drop in feedwater temperature caused by the disappearance of high-pressure heater extraction during cylinder cut-off and its dynamic compensation. Therefore, existing solutions only address the molten salt anti-condensation problem under steady-state low-load scenarios and cannot cope with the instantaneous changes in feedwater heat deficit caused by the sudden loss of high-pressure heater extraction during cylinder cut-off transitions. Furthermore, they lack a feedforward compensation mechanism based on a predictive model.

[0004] Therefore, the existing technology has the problem that the heat gap in the feedwater caused by the disappearance of high-pressure steam extraction after the cylinder cut-off command is issued cannot be predicted and compensated in advance, and can only be passively responded to through feedback adjustment after the feedwater temperature actually drops. This problem urgently needs to be solved. Summary of the Invention

[0005] The purpose of this invention is to provide a feedforward compensation control method and related equipment for feedwater temperature based on molten salt thermal storage. This invention can actively adjust the speed of the molten salt pump and / or the opening of the molten salt flow regulating valve. By utilizing the characteristic of the rapidly adjustable heat release power of the solar thermal molten salt thermal storage system, the molten salt flow rate can be increased within seconds. This instantly compensates for the heat gap caused by the disappearance of steam extraction from the high-pressure heater from the heat source side. This solves the problem that the existing technology can only passively respond through feedback adjustment after the actual drop in feedwater temperature, and cannot predict and compensate for the heat gap in advance.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a feedforward compensation control method for feedwater temperature based on molten salt thermal storage, comprising the following steps: The actual power of the high-pressure cylinder is monitored in real time. When the actual power drops below the set threshold, it is determined that the high-pressure cylinder has entered the zero-output condition and the steam extraction of the high-pressure heater disappears. Obtain the current operating parameters, including the time when the high-pressure heater steam extraction disappears and the current feedwater flow rate; The current operating parameters are input into a pre-established feedwater temperature prediction model, and the predicted value of the feedwater temperature drop is output through the feedwater temperature prediction model; wherein, the feedwater temperature prediction model includes the heat balance principle of the high-pressure heater. Upon receiving a cylinder cutoff command, the feedwater temperature feedforward compensation is achieved by compensating for the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater based on the predicted value of the feedwater temperature drop.

[0007] In some embodiments, the step of outputting a predicted value of the feedwater temperature drop through a feedwater temperature prediction model specifically includes: The feedwater temperature prediction model is based on the heat balance principle of the high-pressure heater. It calculates and outputs the predicted value of the feedwater temperature drop based on the current feedwater flow rate and the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater. The heat gap for water supply is determined based on the steam extraction flow rate, steam extraction enthalpy, and condensate enthalpy of the high-pressure cylinder before cylinder cut-off.

[0008] In some embodiments, the step of compensating for the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater based on the predicted value of the feedwater temperature drop, and obtaining the molten salt flow command to achieve feedwater temperature feedforward compensation, specifically includes: Based on the predicted value of the feedwater temperature drop, the opening of the molten salt flow regulating valve and / or the speed of the molten salt pump are adjusted to obtain the molten salt flow command. According to the molten salt flow command, the flow of molten salt entering the molten salt-feedwater heat exchanger is increased to improve the heat absorption power on the feedwater side and to compensate for the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater.

[0009] In some embodiments, adjusting the opening of the molten salt flow regulating valve and / or the molten salt pump speed specifically includes: Open the molten salt flow regulating valve installed on the molten salt pipeline to initially increase the molten salt flow rate; When the molten salt flow rate increases to more than 80% of the target flow rate, the speed of the molten salt pump set between the high-temperature molten salt tank and the low-temperature molten salt tank is adjusted to the target speed to achieve molten salt flow rate matching.

[0010] In some embodiments, after implementing feedforward compensation for the feedwater temperature, the following steps are further included: When the deviation between the measured temperature at the water supply outlet and the target temperature exceeds the temperature threshold, the molten salt flow rate is adjusted by the feedback controller to obtain the molten salt flow rate after feedback adjustment. When the high-pressure cylinder is given a command to restore output, the system monitors the recovery of steam extraction from the high-pressure heater in real time and gradually reduces the molten salt flow rate after feedback adjustment according to the set rate. When the deviation between the measured temperature at the feedwater outlet and the target temperature does not exceed the temperature threshold and the steam extraction from the high-pressure heater returns to normal, the system completely exits the molten salt compensation control.

[0011] In some embodiments, the adjustment of the molten salt flow rate via the feedback controller specifically includes: The deviation value exceeding the temperature threshold is sent to the PID controller. The PID controller calculates the additional molten salt flow correction amount based on the magnitude of the deviation value, the cumulative amount of the deviation value over time, and the trend of the deviation value. The molten salt flow correction is superimposed on the molten salt flow command for feedwater temperature feedforward compensation to obtain the final molten salt flow command after feedback adjustment. The final molten salt flow command is then output to the molten salt pump or flow control valve to perform the adjustment action. The measured temperature at the water supply outlet is continuously monitored. When the deviation value does not exceed the temperature threshold, the feedback regulation is stopped, and the current molten salt flow rate after feedback regulation is maintained. When the deviation value exceeds the temperature threshold again, the above feedback regulation process of sending the deviation value exceeding the temperature threshold to the PID controller is restarted.

[0012] In some embodiments, the reduction in the molten salt flow rate after feedback adjustment is positively correlated with the proportion of steam recovery from the high-pressure heater.

[0013] Secondly, the present invention provides a feedwater temperature feedforward compensation control system based on molten salt thermal storage, comprising: The operating condition detection module is used to monitor the actual power of the high-pressure cylinder in real time. When the actual power drops below a set threshold, it is determined that the high-pressure cylinder has entered a zero-output operating condition and the steam extraction of the high-pressure heater has disappeared. The module also acquires the current operating parameters, which include the time when the steam extraction of the high-pressure heater disappears and the current feedwater flow rate. The prediction module is used to input the current operating parameters into a pre-established feedwater temperature prediction model and output the predicted value of the feedwater temperature drop through the feedwater temperature prediction model; wherein, the feedwater temperature prediction model includes the thermal balance principle of the high-pressure heater. The feedforward control module is used to compensate for the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater when a cylinder cut-off command is received, based on the predicted value of the feedwater temperature drop.

[0014] Thirdly, the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described feedwater temperature feedforward compensation control method based on molten salt thermal storage.

[0015] Fourthly, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the above-described feedforward compensation control method for feedwater temperature based on molten salt thermal storage.

[0016] The above technical solution has the following advantages or beneficial effects: Firstly, this invention provides a feedwater temperature feedforward compensation control method based on molten salt thermal storage. Through a feedwater temperature prediction model incorporating the heat balance principle of a high-pressure heater, the method can predict the feedwater temperature drop based on the current feedwater flow rate and high-pressure heater extraction parameters the instant the cylinder cut-off command is issued. Based on the predicted value, it actively adjusts the molten salt pump speed and / or the opening of the molten salt flow regulating valve. Utilizing the rapidly adjustable heat release power of the solar thermal molten salt thermal storage system, the molten salt flow rate is increased within seconds, instantly compensating for the heat gap caused by the disappearance of high-pressure heater extraction from the heat source side. This solves the problem of existing technologies that can only passively respond through feedback adjustment after the actual drop in feedwater temperature, and cannot predict and compensate for the heat gap in advance. Simultaneously, this invention employs a feedforward and feedback coordinated control strategy. The system primarily uses feedforward regulation, supplemented by feedback regulation, to stabilize the feedwater temperature to the target range within 3 minutes, control temperature fluctuations within ±5℃, and minimize the deviation of steam parameters at the steam generator outlet to less than 2%. Compared to traditional uncompensated control (stabilization time exceeding 15 minutes and steam parameter deviation exceeding 5%), this significantly shortens the cylinder switching transition time and avoids thermal shock to the steam generator. Furthermore, when the high-pressure cylinder resumes output, the invention gradually withdraws molten salt compensation at a positive correlation rate based on the high-pressure heater extraction steam recovery ratio, and completely withdraws it when the extraction steam recovers to over 80% and the feedwater temperature stabilizes. This achieves a smooth switch between molten salt compensation and high-pressure heater extraction steam heating, effectively avoiding secondary fluctuations in feedwater temperature and comprehensively improving the safety, stability, and economy of deep peak-shaving operation of solar thermal power plants.

[0017] Secondly, this invention provides a feedwater temperature feedforward compensation control system based on molten salt thermal storage. Through the coordinated work of the operating condition detection module, prediction module and feedforward control module, the system actively compensates for the heat gap based on the predicted value based on the thermal balance principle when the cylinder cut-off command is issued. This transforms passive feedback into active feedforward, solving the problem of sudden drop in feedwater temperature from the source, effectively avoiding thermal shock of the steam generator, and improving the safety of deep peak shaving operation of the solar thermal power plant.

[0018] Thirdly, the present invention provides a computer device that, through a processor executing a specific computer program, can efficiently implement the steps of the method of the present invention. When performing data processing tasks, the computer device can accurately perform numerical calculations and logical judgments, avoiding errors caused by human factors. At the same time, since the computer program has high stability and reliability, it can ensure the accuracy and consistency of the data processing results.

[0019] Fourthly, the present invention provides a computer-readable storage medium. By programming the steps of the method of the present invention into a computer program and storing it on the computer-readable storage medium, users can easily load these programs onto any compatible computer device and execute them without rewriting or converting the code, which greatly improves the convenience and flexibility of program execution. Attached Figure Description

[0020] Figure 1 This is a schematic flowchart of the feedforward compensation control method for feedwater temperature based on molten salt thermal storage, as shown in an embodiment of the present invention. Figure 2 This is a schematic diagram of the feedwater temperature feedforward compensation control system based on molten salt thermal storage, as shown in an embodiment of the present invention. Figure 3 This is a schematic diagram of the control logic for the coordinated operation of the feedforward control module and the feedback control module, as shown in an embodiment of the present invention.

[0021] In the diagram, 1. Steam generator; 2. High-pressure cylinder of steam turbine; 3. Intermediate-pressure cylinder of steam turbine; 4. Low-pressure cylinder of steam turbine; 5. High-pressure heater; 6. Molten salt-feedwater heat exchanger; 7. High-temperature molten salt tank; 8. Low-temperature molten salt tank; 9. Molten salt pump; 10. Molten salt flow regulating valve; 11. Deaerator; 12. Low-pressure heater; 13. Feedwater pump; 14. Reheater; 15. Condenser; 16. Operating condition monitoring module; 17. Prediction module; 18. Feedforward control module; 19. Feedback control module; 20. Exit control module; 21. Temperature sensor. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for explanation purposes only and are not intended to limit the scope of the invention.

[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0024] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0025] With the advancement of the "dual carbon" target and the deepening of the construction of new power systems, the demand for flexible peak-shaving capabilities in the power grid is becoming increasingly urgent. Concentrated solar power (CSP), with its molten salt thermal storage system, can achieve 24-hour continuous power generation and deep peak-shaving, becoming an important regulating power source in the new energy power system. Under deep peak-shaving conditions, zero-output operation of the turbine's high-pressure cylinder (cylinder cut-off) is an effective means to further reduce the unit's minimum technical output. During cylinder cut-off, the main steam enters the reheater after being de-cooled and depressurized by the high-pressure bypass valve. The high-pressure cylinder does not perform work, and the unit's output is mainly provided by the intermediate-pressure and low-pressure cylinders. However, cylinder cut-off operation causes the high-pressure cylinder to stop extracting steam, the high-pressure heater loses its heat source, and the feedwater temperature typically drops by 30-50°C. This sudden drop in feedwater temperature has a serious impact on the steam generation system of CSP plants. The sudden drop in feedwater temperature entering the steam generator causes rapid cooling of the heat exchanger walls, generating thermal shock and threatening equipment safety; simultaneously, the decrease in feedwater temperature causes the steam parameters (temperature and pressure) at the steam generator outlet to deviate from the design values, affecting unit efficiency and operational stability. The steam generators in solar thermal power plants typically use molten salt-water / steam heat exchangers, and fluctuations in feedwater temperature are more sensitive to the operating conditions of the heat exchangers.

[0026] In existing technologies, some solutions utilize molten salt thermal storage systems to heat high-pressure feedwater under steady-state conditions to reduce turbine steam extraction and increase unit output. However, these solutions focus on the energy optimization configuration of the thermal storage and feedwater systems under steady-state conditions and do not propose control strategies for the dynamic changes in feedwater temperature during cylinder cut-off transition. Another solution regulates feedwater temperature by connecting a bypass in parallel with the high-pressure heater, but this primarily addresses the molten salt solidification problem caused by excessively low feedwater temperature under low-load conditions, without addressing the sudden drop in feedwater temperature caused by the disappearance of high-pressure heater steam extraction during cylinder cut-off and its dynamic compensation. Furthermore, in deep peak-shaving scenarios for coal-fired units, although some solutions utilize thermal storage loops to heat feedwater during bypass high-pressure heater feedwater to reduce the underenthalpy at the water-cooled wall inlet, this solution targets the wet-to-dry transition process of coal-fired units, which is fundamentally different from the technical scenario and control requirements of cylinder cut-off in concentrated solar power plants, and it lacks a feedforward control mechanism based on predictive models. The core deficiency of existing technologies lies in the lack of a feedwater temperature prediction model and active feedforward control strategy for the transition process of solar thermal power plant cylinder cut-off. After the cylinder cut-off command is issued, the feedwater heat gap caused by the disappearance of blast furnace steam extraction cannot be predicted and compensated in advance. The only response is passive adjustment through feedback after the actual drop in feedwater temperature, leading to significant feedwater temperature fluctuations and an inability to effectively prevent thermal shock to the steam generator. Furthermore, existing solutions do not fully utilize the rapidly adjustable heat release power of the solar thermal molten salt storage system, failing to achieve immediate compensation for the heat gap at the moment of cylinder cut-off.

[0027] Therefore, a feedforward control method is needed that can respond instantly when the cylinder cut-off command is issued, predict the trend of feedwater temperature change based on operating parameters, and actively adjust the heat release power of the molten salt thermal storage system to compensate for the heat gap of the high-pressure heater extraction steam. This method can fundamentally solve the problem of steam generator thermal shock and steam parameter deviation caused by the sudden drop in feedwater temperature under cylinder cut-off conditions from the heat source side, and ensure the safety and economy of deep peak shaving operation of solar thermal power plants.

[0028] This invention provides a feedforward compensation control method for feedwater temperature based on molten salt thermal storage, comprising the following steps: Step 1: Monitor the actual power of the high-pressure cylinder in real time. When the actual power drops below the set threshold, it is determined that the high-pressure cylinder has entered the zero-output condition and the steam extraction of the high-pressure heater disappears. Step 2: Obtain the current operating parameters, including the time when the high-pressure heater steam extraction disappears and the current feedwater flow rate; Step 3: Input the current operating parameters into the pre-established feedwater temperature prediction model, and output the predicted value of the feedwater temperature drop through the feedwater temperature prediction model; wherein, the feedwater temperature prediction model includes the heat balance principle of the high-pressure heater. Step 4: Upon receiving the cylinder cut-off command, the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater is compensated based on the predicted value of the feedwater temperature drop, thereby achieving feedwater temperature feedforward compensation.

[0029] Compared with existing technologies, this invention determines the cylinder cut-off condition by real-time monitoring of the high-pressure cylinder power and utilizes a feedwater temperature prediction model based on the thermal balance principle of the high-pressure heater. When the cylinder cut-off command is issued, the feedwater temperature drop can be predicted based on the current feedwater flow rate and high-pressure heater extraction parameters. Based on the predicted value, the heat gap in the feedwater caused by the disappearance of high-pressure heater extraction is actively compensated, transforming passive feedback into active feedforward. This solves the problem that existing technologies cannot predict and compensate for heat gaps in advance. At the same time, this invention fully utilizes the rapidly adjustable heat release power of the solar thermal molten salt storage system to compensate for the heat gap instantly at the moment of cylinder cut-off. This effectively avoids the thermal shock of steam generator 1 and the deviation of steam parameters caused by a sudden drop in feedwater temperature, ensuring the safety and economy of deep peak-shaving operation of the solar thermal power plant.

[0030] Example 1: This embodiment provides a feedforward compensation control method for feedwater temperature based on molten salt thermal storage. (See also...) Figure 1 This includes the following steps: Step 1: Monitor the actual power of the high-pressure cylinder in real time. When the actual power drops below the set threshold, it is determined that the high-pressure cylinder has entered the zero-output condition and the steam extraction of the high-pressure heater disappears.

[0031] In some embodiments, this method is applied to concentrated solar power (CSP) systems, see [link to relevant documentation]. Figure 2 As shown, the solar thermal power generation system includes a steam generator 1, a high-pressure cylinder 2 of a steam turbine, an intermediate-pressure cylinder 3 of a steam turbine, a low-pressure cylinder 4 of a steam turbine, a high-pressure heater 5, a molten salt-feedwater heat exchanger 6, and a molten salt thermal storage system. The steam generator 1 is sequentially connected to the high-pressure cylinder 2, intermediate-pressure cylinder 3, low-pressure cylinder 4, high-pressure heater 5, and molten salt-feedwater heat exchanger 6. The molten salt thermal storage system includes a high-temperature molten salt tank 7, a low-temperature molten salt tank 8, and a molten salt pump 9. The high-temperature molten salt tank 7 is connected to the low-temperature molten salt tank 8 via the molten salt pump 9. The outlet of the molten salt pump 9 is connected to the molten salt side inlet of the molten salt-feedwater heat exchanger 6 via a molten salt pipeline. A molten salt flow regulating valve 10 is installed on the molten salt pipeline. The feedwater circuit also includes a reheater 14 connected to the steam generator 1, a condenser 15, a low-pressure heater 12, a deaerator 11, and a feedwater pump 13 connected in sequence. Feedwater passes sequentially through the low-pressure heater 12, deaerator 11, feedwater pump 13, high-pressure heater 5, and molten salt-feedwater heat exchanger 6 before entering the steam generator 1. The superheated steam generated by the steam generator 1 enters the high-pressure cylinder 2 to perform work. The exhaust steam from the high-pressure cylinder 2 is heated by the reheater 14 and then enters the intermediate-pressure cylinder 3 and low-pressure cylinder 4 to perform work. The exhaust steam from the low-pressure cylinder 4 enters the condenser 15 for condensation. The steam extracted from the high-pressure cylinder 2 serves as the heat source for the high-pressure heater 5, heating the feedwater to the design temperature.

[0032] In some embodiments, under deep peak shaving conditions, when the high-pressure cylinder 2 needs to be reduced to zero output, the control system receives a zero-output switching command for the high-pressure cylinder. This command can be obtained by monitoring the high-pressure cylinder power command or the actual power measurement value, and the high-pressure cylinder power threshold is set to 5% of the rated power. When the high-pressure cylinder power command is detected to drop below this threshold or the actual power measurement value is close to zero, it is determined that the high-pressure cylinder has entered the zero-output condition. At the same time, the control system monitors the pressure sensor of the extraction steam pipeline of the high-pressure heater 5, and performs double confirmation when the extraction steam pressure is lower than the set lower limit, thereby improving the reliability of the condition judgment. At this time, the main steam no longer enters the high-pressure cylinder 2 to do work, but instead enters the reheater 14 directly through the high-pressure bypass. After the high-pressure cylinder 2 stops doing work, it no longer supplies extraction steam to the high-pressure heater 5, the high-pressure heater 5 loses its heat source, and the feedwater temperature will drop significantly.

[0033] Step 2: Obtain the current operating parameters, which include the time when the steam extraction of the high-pressure heater 5 disappears and the current feedwater flow rate.

[0034] Step 3: Input the current operating parameters into the pre-established feedwater temperature prediction model, and output the predicted value of the feedwater temperature drop through the feedwater temperature prediction model; wherein, the feedwater temperature prediction model includes the heat balance principle of the high-pressure heater 5.

[0035] In some embodiments, the step of outputting a predicted value of the feedwater temperature drop through a feedwater temperature prediction model specifically includes: The feedwater temperature prediction model is based on the heat balance principle of the high-pressure heater 5. It calculates and outputs the predicted value of the feedwater temperature drop based on the current feedwater flow rate and the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater 5. The feedwater heat gap is determined based on the steam extraction flow rate, steam extraction enthalpy, and condensate enthalpy of the high-pressure cylinder before cylinder cut-off.

[0036] In some embodiments, to avoid thermal shock to the steam generator 1 caused by a sudden drop in feedwater temperature, this embodiment establishes a feedwater temperature prediction model based on a mechanistic model. This model is based on the heat balance equation of the high-pressure heater 5 and calculates the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater 5.

[0037] Specifically, the heat balance equation for the high-pressure heater 5 before cylinder cutting is: ; In the formula, This indicates the heat exchange power (kW) of high-pressure heater 5. This indicates the mass flow rate of steam extracted from the high-pressure cylinder (kg / s). This indicates the extraction enthalpy (kJ / kg). Indicates the hydrophobic enthalpy (kJ / kg); Indicates the water supply mass flow rate (kg / s); This indicates the specific heat capacity of the feedwater (kJ / (kg·℃)). This indicates the outlet feedwater temperature (°C) of high-pressure heater 5. This indicates the inlet feedwater temperature (°C) of high-pressure heater 5.

[0038] In some embodiments, the water supply temperature prediction model employs a data-driven model based on a neural network, and the training steps include: The control system collects no fewer than 200 sets of historical cylinder cut-off operating data, including the timing of the cylinder cut-off command trigger. Target load (MW), the moment when the extraction steam of the historical high-pressure heater disappeared. (s) Historical feedwater flow rate during cylinder switching (kg / s) and the corresponding historical decrease in feedwater temperature (°C). Normalize the input data: ; In the formula, Indicates the first One input feature; Indicates the first The minimum value of each input feature; Indicates the first The maximum value of each input feature.

[0039] A backpropagation (BP) neural network model was trained using the cylinder cut-off command, target load, historical high-pressure heater 5 extraction steam disappearance time, and historical feedwater flow rate as inputs, and the historical feedwater temperature drop rate as output. The BP neural network adopted a 4-12-1 structure (4 input nodes, 12 hidden nodes, and 1 output node), and the ReLU activation function was used. Training parameters: learning rate The maximum number of iterations is 5000, the ratio of training set to test set is 7:3, and the root mean square error of the test set is... When the temperature reaches a certain level (℃), the model training is considered complete. Upon issuing the cylinder cut-off command, the control system inputs the current operating parameters into the trained neural network model to obtain the predicted value of the feedwater temperature drop. Based on this prediction, the speed of the molten salt pump 9 is adjusted forward to achieve feedwater temperature compensation control. After each cylinder cut-off operation, the data from that operation (input parameters and actual feedwater temperature drop) is added to the training dataset, triggering online fine-tuning and updating of the model, with the learning rate reduced to a certain value. The model is iterated 200 times to ensure that it continuously adapts to changes in the unit's operating status.

[0040] Step 4: Upon receiving the cylinder cut-off command, the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater 5 is compensated based on the predicted value of the feedwater temperature drop, thereby achieving feedwater temperature feedforward compensation.

[0041] In some embodiments, step 4 specifically includes: Based on the predicted value of the feedwater temperature drop, the opening of the molten salt flow regulating valve 10 and / or the speed of the molten salt pump 9 are adjusted to obtain the molten salt flow command. According to the molten salt flow command, the flow of molten salt entering the molten salt-feedwater heat exchanger 6 is increased to improve the heat absorption power on the feedwater side and to compensate for the heat gap in the feedwater caused by the disappearance of steam extraction from the high-pressure heater 5.

[0042] In some embodiments, the heat gap in the water supply after cylinder cut-off The calculation formula is: ; In the formula, This indicates the high-pressure cylinder extraction steam flow rate (kg / s) before cylinder cutting. This indicates the enthalpy of the extracted steam before cylinder cutting (kJ / kg). This indicates the enthalpy of condensate before cylinder cut-off (kJ / kg).

[0043] The formula for calculating the required molten salt side compensation power is as follows: ; In the formula, Indicates the required molten salt side compensation power; This indicates the predicted decrease in feedwater temperature (°C).

[0044] Furthermore, the target molten salt flow rate is calculated based on the molten salt side compensation power. : ; In the formula, This indicates the specific heat capacity of molten salt (kJ / (kg·℃)). This indicates the molten salt side inlet temperature (°C) of molten salt-feedwater heat exchanger 6. For reference, the molten salt outlet temperature (°C) is used. Based on the pump similarity law, the target molten salt pump speed is 9. The calculation formula is: ; In the formula, This indicates the rotational speed (r / min) of the molten salt pump 9 before cylinder cutting; This represents the molten salt flow rate (kg / s) before cylinder cut-off. The above derivation chain completely establishes the feedforward calculation path from the disappearance of steam extraction from the high-pressure heater to the target molten salt pump speed, providing the control system with an accurate feedforward control target.

[0045] In some embodiments, at the instant the cylinder cut-off command is issued, the control system adjusts the rotational speed of the molten salt pump 9 based on the predicted decrease in feedwater temperature. Specifically, based on the target molten salt flow rate... Calculate the target molten salt pump speed 9 The control system adjusts the speed of molten salt pump 9 to the target speed, increasing the molten salt flow rate to the target flow rate, and increasing the heat release power on the molten salt side of the molten salt-feed water heat exchanger 6 to the compensated power. This compensates for the heat loss in the feedwater caused by the disappearance of steam extraction from the high-pressure heater 5, thus maintaining a stable feedwater temperature.

[0046] In some embodiments, adjusting the opening of the molten salt flow regulating valve 10 and / or the rotational speed of the molten salt pump 9 specifically includes: Open the molten salt flow regulating valve 10 installed on the molten salt pipeline to initially increase the molten salt flow rate; when the molten salt flow rate increases to more than 80% of the target flow rate, adjust the speed of the molten salt pump 9 installed between the high-temperature molten salt tank 7 and the low-temperature molten salt tank 8 to the target speed to achieve molten salt flow rate matching.

[0047] In some embodiments, molten salt flow rate regulation is achieved by coordinating the rotational speed of the molten salt pump 9 and the opening of the molten salt flow rate regulating valve 10. The molten salt flow rate achievement rate is defined. ,when At that time, it was in the rapid response phase, when The system then switches to the fine-tuning stage. During the rapid response stage, the control system quickly opens the molten salt flow regulating valve 10, with a valve opening adjustment rate of [missing information]. (% / s), the valve opening degree will be increased within 5 seconds. Adjust the opening degree before cylinder cutting to the target opening degree corresponding to 80% of the molten salt flow rate achievement rate. This allows for a rapid initial increase in molten salt flow rate, preventing a significant drop in feedwater temperature. During the fine-tuning phase, the control system slowly adjusts the speed of the molten salt pump 9, with a pump speed adjustment rate of [missing information]. (r / min / s), adjust the speed of molten salt pump 9 from the current speed to the target speed within 30 seconds. Simultaneously, the valve opening is adjusted to a steady-state opening corresponding to the target molten salt flow rate, achieving precise matching of the molten salt flow rate and ensuring that the heat release power on the molten salt side is precisely equal to the compensation power. This coordinated regulation strategy fully leverages the respective advantages of rapid valve response and precise pump speed adjustment, balancing rapid response and fine control to improve control performance.

[0048] Step 5: When the deviation between the measured temperature at the water outlet and the target temperature exceeds the temperature threshold, the molten salt flow rate is adjusted by the feedback controller to obtain the molten salt flow rate after feedback adjustment.

[0049] In some embodiments, step 5 specifically includes: Step 5.1: When the deviation between the measured temperature of the water supply outlet and the target temperature exceeds the temperature threshold, the deviation exceeding the temperature threshold is sent to the PID controller. The PID controller calculates the additional molten salt flow correction amount based on the magnitude of the deviation, the cumulative amount of the deviation over time, and the trend of the deviation.

[0050] Step 5.2: Add the molten salt flow correction amount to the molten salt flow command for feedwater temperature feedforward compensation to obtain the final molten salt flow command after feedback adjustment. Output the final molten salt flow command to the molten salt pump 9 or the flow regulating valve to perform the adjustment action.

[0051] Step 5.3: Continuously monitor the measured temperature of the water supply outlet. When the deviation value does not exceed the temperature threshold, stop the feedback regulation and maintain the current molten salt flow rate after feedback regulation. When the deviation value exceeds the temperature threshold again, restart the above feedback regulation process of sending the deviation value exceeding the temperature threshold to the PID controller.

[0052] In some embodiments, the control system supplements feedforward regulation with feedback regulation of the water outlet temperature. The feedback controller employs a PID controller, and the temperature deviation is defined as: ; In the formula, Indicates the target feedwater temperature (°C); This represents the measured temperature (°C) at the water supply outlet. The PID control law is as follows: ; In the formula, This indicates the additional molten salt flow rate correction required (kg / s). This indicates the deviation value (the deviation value exceeding the temperature threshold). This is the proportionality coefficient; Indicates the integral coefficient; Represents the differential coefficient; , and The unit is tuned using the Ziegler-Nichols method based on its thermodynamic characteristics.

[0053] Set the water supply temperature deviation threshold ℃, when PID feedback regulation is initiated at the appropriate time; when At this time, the PID control weight is reduced to 0.2, with feedforward control becoming the primary method to avoid control oscillations caused by frequent adjustments. The control system adjusts according to the control input. The speed of the molten salt pump 9 is finely adjusted to compensate for the prediction error caused by the feedforward adjustment, ensuring that the feedwater temperature remains stable within the target temperature range.

[0054] Step 6: Upon receiving the command to restore output of the high-pressure cylinder, monitor the recovery of steam extraction from the high-pressure heater 5 in real time, and gradually reduce the molten salt flow rate after feedback adjustment according to the set rate. When the deviation between the measured temperature at the feedwater outlet and the target temperature does not exceed the temperature threshold, and the steam extraction from the high-pressure heater 5 returns to normal, completely exit the molten salt compensation control.

[0055] In some embodiments, the reduction in the molten salt flow rate after feedback adjustment is positively correlated with the proportion of steam recovery from the high-pressure heater 5.

[0056] In some embodiments, when the high-pressure cylinder resumes output, the control system receives a command to resume output and monitors the recovery status of the extraction steam flow of the high-pressure heater 5. Based on the recovery ratio of the extraction steam flow of the high-pressure heater 5, the control system gradually reduces the molten salt flow rate at a set rate. Molten salt flow rate reduction rate. The calculation formula is: ; In the formula, This indicates the set exit time (s), which is recommended to be 60-120s, determined based on the unit's response characteristics. During the exit process, the adjusted molten salt flow rate is fed back. Decrease gradually according to the following pattern: ; In the formula, This indicates the current steam extraction flow rate (kg / s) of the high-pressure heater 5. This indicates the steam extraction flow rate (kg / s) before cylinder cut-off. Indicates the exit start time (s).

[0057] when and At that time, molten salt compensation is completely discontinued, and the molten salt flow rate is restored to [normal value]. During the shutdown process, the control system simultaneously monitors the feedwater temperature to ensure that the feedwater temperature remains stable within the target temperature range.

[0058] To verify the technical effectiveness of the feedwater temperature feedforward compensation control method based on molten salt thermal storage provided by this invention, a comparative experiment was conducted on a 50MW tower solar thermal power generation unit (including steam generator 1, high-pressure cylinder 2, medium-pressure cylinder 3, low-pressure cylinder 4, etc.).

[0059] The experimental condition was the high-pressure cylinder 2 of the steam turbine being cut off. The rated feedwater temperature of the unit was 240℃ (detected by temperature sensor 21), the rated extraction steam flow rate of the high-pressure heater 5 was 15 kg / s, the feedwater flow rate before cylinder cutoff was 65 kg / s (delivered by feedwater pump 13), and the rated molten salt flow rate of the molten salt-feedwater heat exchanger 6 was 80 kg / s (supplied by the high-temperature molten salt tank 7, driven by the molten salt pump 9, regulated by the molten salt flow regulating valve 10, and finally returned to the low-temperature molten salt tank 8). The molten salt inlet temperature was 390℃. The disappearance of extraction steam from the high-pressure heater 5 resulted in an expected drop in feedwater temperature of 40℃. The comparison object was the traditional uncompensated control method, i.e., after cylinder cutoff, no compensation was used from the molten salt-feedwater heat exchanger 6, and only the steam generator 1 itself was regulated. After the cylinder cut-off command is issued, the operating condition detection module 16 identifies the cylinder cut-off status, the prediction module 17 calculates the feedforward compensation, and the feedforward control module 18 increases the molten salt flow rate from 80 kg / s to 118 kg / s (an increase of approximately 48%) through the molten salt flow rate regulating valve 10, with an adjustment time of approximately 8 seconds. The feedback control module 19 (PID control) starts after t=30s, fine-tuning the molten salt flow rate between 118-122 kg / s through the molten salt flow rate regulating valve 10, and stabilizing the feedwater temperature (feedback from temperature sensor 21) within the range of 239-241℃. The feedwater temperature data (recorded by temperature sensor 21) at different time points during the experiment are shown in the table below: Table 1. Feedwater temperature data at different time points

[0060] Experimental results show that when using the method of this invention, the feedwater temperature stabilizes within the target temperature range within 3 minutes after the cylinder cut-off command is issued, with temperature fluctuations not exceeding ±5℃. The steam parameters at the outlet of steam generator 1 deviate by less than 2%, and no thermal shock occurs. When using the traditional uncompensated control method, the feedwater temperature remains unstable 15 minutes after the cylinder cut-off command is issued, with temperature fluctuations reaching ±20℃. Steam generator 1 experiences significant thermal shock, and steam parameters deviate by more than 5%. Compared to traditional uncompensated control, the method of this application shortens the cylinder cut-off transition time by 80% (from 15 minutes to 3 minutes), reduces steam parameter deviation from more than 5% to less than 2%, and improves unit efficiency by approximately 0.3 percentage points. Comparative experimental results demonstrate that the control method provided in this application can effectively avoid thermal shock to steam generator 1 caused by a sudden drop in feedwater temperature, shorten the feedwater temperature stabilization time, maintain stable steam parameters, and improve the unit's deep peak-shaving capability.

[0061] This invention establishes a feedwater temperature prediction model, which can predict the future feedwater temperature drop trend the instant the cylinder cut-off command is issued. Based on the predicted value, the molten salt flow rate of the molten salt-feedwater heat exchanger 6 is increased in a feedforward manner, so that the heat release power on the molten salt side matches the heat gap in the feedwater caused by the disappearance of steam extraction from the high-pressure heater 5. This fundamentally solves the problem of sudden drop in feedwater temperature from the heat source side, avoids thermal shock to the steam generator 1, and protects equipment safety. Compared with the existing technology, which can only passively adjust after the actual drop in feedwater temperature, the feedforward control strategy of this invention can predict and compensate for the heat gap in advance, controlling the feedwater temperature fluctuation within ±5℃. At the same time, it makes full use of the rapid adjustable heat release power of the solar thermal molten salt heat storage system. By adjusting the speed of the molten salt pump 9 or the opening of the molten salt flow regulating valve 10, the heat gap is compensated instantly at the moment of cylinder cut-off, maintaining stable feedwater temperature, reducing the disturbance of the steam parameters at the outlet of the steam generator 1 to cylinder cut-off, ensuring that the steam parameter deviation is less than 2%, meeting the requirements of rapid response, and overcoming the shortcomings of large thermal inertia and slow response of thermal power unit heat storage systems. This application employs a combined feedforward and feedback control system, with feedforward regulation as the primary method and feedback regulation as a secondary method. Feedforward compensates for heat deficits in advance based on a predictive model, while feedback provides fine compensation for prediction errors, ensuring that the feedwater temperature remains stable within the target range. This reduces the stabilization time to less than 3 minutes, significantly accelerating the deep peak-shaving response rate compared to the more than 15 minutes required by traditional uncompensated control, thereby improving the peak-shaving flexibility and economy of the solar thermal power plant. When resuming normal operation after cylinder cut-off, the recovery of steam extraction from the high-pressure heater 5 is monitored, and molten salt compensation is gradually withdrawn at a set rate, achieving a smooth switch between molten salt compensation and high-pressure heater steam extraction heating. This avoids feedwater temperature fluctuations, ensures stable unit operation, and improves the utilization rate of the molten salt thermal storage system and the overall operating efficiency of the solar thermal power plant.

[0062] Example 2: In one embodiment of the present invention, a feedwater temperature feedforward compensation control system based on molten salt thermal storage is provided to implement the feedwater temperature feedforward compensation control method based on molten salt thermal storage described in Embodiment 1. (See also...) Figure 2 and Figure 3 ,include: The operating condition detection module 16 is used to monitor the actual power of the high-pressure cylinder in real time. When the actual power drops to less than a set threshold, it is determined that the high-pressure cylinder has entered a zero-output operating condition and the steam extraction of the high-pressure heater 5 disappears. The module also acquires the current operating parameters, which include the time when the steam extraction of the high-pressure heater 5 disappears and the current feedwater flow rate. Prediction module 17 is used to input the current operating parameters into a pre-established feedwater temperature prediction model and output the predicted value of the feedwater temperature drop through the feedwater temperature prediction model; wherein, the feedwater temperature prediction model includes the heat balance principle of the high-pressure heater 5. Feedforward control module 18 is used to compensate for the feedwater heat gap caused by the disappearance of steam extraction from high-pressure heater 5 when a cylinder cut-off command is received, based on the predicted value of the feedwater temperature drop, thereby realizing feedforward compensation of feedwater temperature.

[0063] The feedback control module 19 is connected to the temperature sensor 21. When the deviation between the measured temperature at the water outlet and the target temperature exceeds the temperature threshold, the feedback controller adjusts the molten salt flow rate to obtain the adjusted molten salt flow rate. The exit control module 20 is used to monitor the steam extraction recovery status of the high-pressure heater 5 in real time when it receives the high-pressure cylinder recovery output command. It gradually reduces the molten salt flow rate after feedback adjustment according to the set rate. When the deviation between the measured temperature of the feedwater outlet and the target temperature does not exceed the temperature threshold and the steam extraction of the high-pressure heater 5 returns to normal, it completely exits the molten salt compensation control.

[0064] In summary, the feedwater temperature feedforward compensation control system based on molten salt thermal storage provided in this embodiment achieves feedforward compensation control of feedwater temperature under cylinder cut-off conditions through the coordinated operation of the operating condition detection module 16, prediction module 17, feedforward control module 18, feedback control module 19, exit control module 20, molten salt pump 9 and / or molten salt flow regulating valve 10, and temperature sensor 21. The operating condition detection module 16 monitors and determines the cylinder cut-off condition in real time, the prediction module 17 predicts the feedwater temperature drop based on the heat balance principle of the high-pressure heater 5, the feedforward control module 18 actively adjusts the molten salt flow to compensate for the heat gap based on the predicted value, the feedback control module 19 makes fine adjustments based on the measured temperature deviation, and the exit control module 20 smoothly exits molten salt compensation when the high-pressure cylinder resumes output. This system fully utilizes the rapid and adjustable heat release power of the solar thermal molten salt thermal storage system to achieve instant compensation of the heat gap at the moment of cylinder cut-off, avoiding thermal shock to the steam generator caused by a sudden drop in feedwater temperature, and ensuring the safety and economy of deep peak-shaving operation of the solar thermal power plant.

[0065] Example 3: This embodiment provides a computer device, which includes a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the memory. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The processor is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in a computer storage medium to achieve a corresponding method flow or corresponding function. The processor described in this embodiment can be used to perform related operations of a feedforward compensation control method for feedwater temperature based on molten salt thermal storage.

[0066] This embodiment provides a computer-readable storage medium, which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space containing the terminal's operating system; and this storage space also contains one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM (Random Access Memory) or non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the feedforward compensation control method for feedwater temperature based on molten salt thermal storage in this embodiment.

[0067] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0068] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0069] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0070] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A feedforward compensation control method for feedwater temperature based on molten salt thermal storage, characterized in that, Includes the following steps: The actual power of the high-pressure cylinder is monitored in real time. When the actual power drops below the set threshold, it is determined that the high-pressure cylinder has entered the zero-output condition and the steam extraction of the high-pressure heater disappears. Obtain the current operating parameters, including the time when the high-pressure heater steam extraction disappears and the current feedwater flow rate; The current operating parameters are input into a pre-established feedwater temperature prediction model, and the predicted value of the feedwater temperature drop is output through the feedwater temperature prediction model; wherein, the feedwater temperature prediction model includes the heat balance principle of the high-pressure heater. Upon receiving a cylinder cutoff command, the feedwater temperature feedforward compensation is achieved by compensating for the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater based on the predicted value of the feedwater temperature drop.

2. The feedwater temperature feedforward compensation control method based on molten salt thermal storage according to claim 1, characterized in that, The step of outputting the predicted value of the feedwater temperature drop through the feedwater temperature prediction model specifically includes: The feedwater temperature prediction model is based on the heat balance principle of the high-pressure heater. It calculates and outputs the predicted value of the feedwater temperature drop based on the current feedwater flow rate and the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater. The heat gap for water supply is determined based on the steam extraction flow rate, steam extraction enthalpy, and condensate enthalpy of the high-pressure cylinder before cylinder cut-off.

3. The feedwater temperature feedforward compensation control method based on molten salt thermal storage according to claim 1, characterized in that, The process of compensating for the feedwater heat deficit caused by the disappearance of steam extraction from the high-pressure heater based on the predicted feedwater temperature drop, and obtaining the molten salt flow command to achieve feedwater temperature feedforward compensation, specifically includes: Based on the predicted value of the feedwater temperature drop, the opening of the molten salt flow regulating valve and / or the speed of the molten salt pump are adjusted to obtain the molten salt flow command. According to the molten salt flow command, the flow of molten salt entering the molten salt-feedwater heat exchanger is increased to improve the heat absorption power on the feedwater side and to compensate for the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater.

4. The feedwater temperature feedforward compensation control method based on molten salt thermal storage according to claim 3, characterized in that, The adjustment of the molten salt flow rate regulating valve opening and / or the molten salt pump speed specifically includes: Open the molten salt flow regulating valve installed on the molten salt pipeline to initially increase the molten salt flow rate; When the molten salt flow rate increases to more than 80% of the target flow rate, the speed of the molten salt pump set between the high-temperature molten salt tank and the low-temperature molten salt tank is adjusted to the target speed to achieve molten salt flow rate matching.

5. The feedwater temperature feedforward compensation control method based on molten salt thermal storage according to claim 1, characterized in that, After implementing feedforward compensation for feedwater temperature, the following steps are also included: When the deviation between the measured temperature at the water supply outlet and the target temperature exceeds the temperature threshold, the molten salt flow rate is adjusted by the feedback controller to obtain the molten salt flow rate after feedback adjustment. When the high-pressure cylinder is given a command to restore output, the system monitors the recovery of steam extraction from the high-pressure heater in real time and gradually reduces the molten salt flow rate after feedback adjustment according to the set rate. When the deviation between the measured temperature at the feedwater outlet and the target temperature does not exceed the temperature threshold and the steam extraction from the high-pressure heater returns to normal, the system completely exits the molten salt compensation control.

6. The feedwater temperature feedforward compensation control method based on molten salt thermal storage according to claim 5, characterized in that, The adjustment of the molten salt flow rate via the feedback controller specifically includes: The deviation value exceeding the temperature threshold is sent to the PID controller. The PID controller calculates the additional molten salt flow correction amount based on the magnitude of the deviation value, the cumulative amount of the deviation value over time, and the trend of the deviation value. The molten salt flow correction is superimposed on the molten salt flow command for feedwater temperature feedforward compensation to obtain the final molten salt flow command after feedback adjustment. The final molten salt flow command is then output to the molten salt pump or flow control valve to perform the adjustment action. The measured temperature at the water supply outlet is continuously monitored. When the deviation value does not exceed the temperature threshold, the feedback regulation is stopped, and the current molten salt flow rate after feedback regulation is maintained. When the deviation value exceeds the temperature threshold again, the above feedback regulation process of sending the deviation value exceeding the temperature threshold to the PID controller is restarted.

7. The feedwater temperature feedforward compensation control method based on molten salt thermal storage according to claim 5, characterized in that, The reduction in the molten salt flow rate after feedback adjustment is positively correlated with the proportion of steam recovery from the high-pressure heater.

8. A feedforward compensation control system for feedwater temperature based on molten salt thermal storage, characterized in that, The feedwater temperature feedforward compensation control method based on molten salt thermal storage as described in any one of claims 1-7 includes: The operating condition detection module is used to monitor the actual power of the high-pressure cylinder in real time. When the actual power drops below a set threshold, it is determined that the high-pressure cylinder has entered a zero-output operating condition and the steam extraction of the high-pressure heater has disappeared. The module also acquires the current operating parameters, which include the time when the steam extraction of the high-pressure heater disappears and the current feedwater flow rate. The prediction module is used to input the current operating parameters into a pre-established feedwater temperature prediction model and output the predicted value of the feedwater temperature drop through the feedwater temperature prediction model; wherein, the feedwater temperature prediction model includes the thermal balance principle of the high-pressure heater. The feedforward control module is used to compensate for the feedwater heat gap caused by the disappearance of steam extraction from the high-pressure heater when a cylinder cut-off command is received, based on the predicted value of the feedwater temperature drop.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the feedforward compensation control method for feedwater temperature based on molten salt thermal storage as described in any one of claims 1-7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the feedforward compensation control method for feedwater temperature based on molten salt thermal storage as described in any one of claims 1-7.

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