Thermal storage power feed-based fast load variation control method for photo-thermal unit and related equipment

Abstract

This invention belongs to the field of concentrated solar power (CSP) control technology and discloses a rapid load change control method and related equipment for CSP units based on thermal storage power feedforward. The rapid load change control method for CSP units based on thermal storage power feedforward includes calculating the difference between the turbine's demand power sequence and the collector field's output power sequence to obtain a power gap sequence; obtaining a molten salt flow rate adjustment amount through feedforward adjustment based on the sign and magnitude of the power gap sequence; obtaining a molten salt flow rate correction amount through feedback adjustment based on the difference between the turbine's actual output and target output; constraining and limiting the high-temperature molten salt tank level according to a preset liquid level threshold to obtain a liquid level constraint limit amount; and obtaining the final molten salt flow rate command based on the molten salt flow rate adjustment amount, the molten salt flow rate correction amount, and the constraint limit amount, thereby realizing rapid load change control of the CSP unit. This invention avoids the response lag problem caused by feedback control waiting for the actual power deviation to occur before taking action.

Description

Technical Field

[0001] This invention relates to the field of concentrated solar power (CSP) control technology, specifically to a rapid load change control method and related equipment for CSP units based on thermal storage power feedforward. Background Technology

[0002] Concentrated solar power (CSP) technology converts direct solar irradiance into high-temperature heat energy through a concentrating solar collector system. It then utilizes a molten salt thermal storage system to store this heat energy for extended periods and release it on demand. Finally, steam is generated by a steam generator to drive a turbine for power generation. Unlike photovoltaic (PV) and wind power, which have intermittent and random power outputs, CSP plants equipped with large-capacity dual-tank molten salt thermal storage systems (typically with a storage duration of 8 to 15 hours) can achieve continuous and controllable power generation 24 hours a day. Therefore, in my country's new power system, which is dominated by new energy sources, CSP is playing an increasingly important role in peak shaving and frequency regulation.

[0003] Existing concentrated solar power (CSP) systems largely adopt the control architecture of traditional thermal power units, relying primarily on feedback control for load tracking. Under this architecture, the control system uses the deviation between the actual turbine output and the target output as the feedback signal, initiating adjustment only when this deviation occurs. However, a CSP system is a strongly coupled, multi-disturbance system comprising a collector field, a thermal storage system, and a turbine. The output thermal power of the collector field is significantly affected by real-time fluctuations in direct solar irradiance. Meteorological disturbances such as cloud cover can cause a sharp drop in collector field output power within minutes, and this disturbance cannot be actively eliminated through conventional adjustment methods. Furthermore, when the dispatching agency issues a load change command, the control system needs to coordinate the actions of the collector field, thermal storage system, and turbine to complete the power adjustment. When there are irradiation disturbances on the collector side and command changes on the load side, the existing feedback control strategy that relies on actual power deviation can only passively wait for the deviation to occur before making adjustments. There is an unavoidable response lag between the occurrence of the deviation and the completion of the control action. This causes key parameters such as steam temperature and pressure to deviate from the design values ​​during the load transition process, affecting the unit's operating efficiency and equipment safety. It also restricts the ability of solar thermal power units to participate in the grid's rapid frequency regulation and peak shaving, making it difficult to meet the grid's engineering requirements for the unit's rapid load change response rate.

[0004] Therefore, the existing technology has an unavoidable response lag between the generation of deviation and the completion of control action, which urgently needs to be solved. Summary of the Invention

[0005] The purpose of this invention is to provide a rapid load change control method and related equipment for solar thermal power units based on thermal storage power feedforward. This invention can predict the future power shortage trend and actively implement adjustment at the moment the scheduling command is issued through the feedforward control mechanism, avoiding the response lag problem caused by feedback control waiting for the actual power deviation to occur before taking action.

[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 method for rapid load change control of a solar thermal power unit based on thermal storage power feedforward, comprising the following steps: Receive the sequence of scheduling load instructions in the future time domain and convert it into a sequence of turbine demand thermal power based on the unit's thermal model; Obtain the predicted value of direct normal irradiance in the future time domain, and generate the output power sequence of the collector field by combining it with the collector field thermodynamic model; The power gap sequence is obtained by calculating the difference between the turbine demand power sequence and the collector field output power sequence. The molten salt flow rate adjustment amount is obtained through feedforward regulation based on the sign and magnitude of the power gap sequence. The molten salt flow correction is obtained through feedback adjustment based on the difference between the actual output and the target output of the steam turbine. The liquid level in the high-temperature molten salt tank is constrained and limited according to a preset liquid level threshold, and the liquid level constraint limit is obtained. Based on the molten salt flow rate adjustment, molten salt flow rate correction, and constraint limits, the final molten salt flow rate command is obtained, enabling rapid load change control of the solar thermal unit.

[0007] In some embodiments, receiving a sequence of scheduling load instructions in the future time domain, and converting it into a turbine demand thermal power sequence based on the unit's thermal model, specifically includes: Receive the sequence of scheduling load commands within the next 5-30 minutes in the time domain, and obtain the efficiency of the steam generation system, the efficiency of the steam turbine, and the power of the auxiliary equipment; The required thermal power input value of the turbine at each moment is obtained by superimposing the dispatch load command and auxiliary power at each moment, and combining the efficiency of the steam generation system and the turbine efficiency. Arrange the thermal power input values ​​at each moment in chronological order to form the turbine's required thermal power sequence.

[0008] In some embodiments, obtaining the predicted direct normal irradiance value in the future time domain and generating the collector field output power sequence by combining it with the collector field thermodynamic model specifically includes: The direct normal irradiance prediction value for the next 5-30 minutes is obtained, and the total area of ​​the solar collector, the efficiency of the solar collector, and the heat loss parameters of the pipeline are obtained. The efficiency of the solar collector is dynamically determined based on the irradiance and the inlet and outlet temperatures of the molten salt, and the heat loss of the pipeline is determined based on the pipeline length, the insulation material, and the ambient temperature. For each moment, the predicted direct normal irradiance is multiplied by the total area of ​​the collector and the collector efficiency, and then the heat loss in the pipes is subtracted to obtain the output power of the collector field at the current moment. The output power of the heat collection field at each moment is arranged in chronological order to form a sequence of heat collection field output power.

[0009] In some embodiments, obtaining the molten salt flow rate adjustment amount through feedforward adjustment based on the sign and magnitude of the power gap sequence specifically includes: When the power gap in the power gap sequence is positive, the thermal storage system switches to heat release mode. Based on the size of the power gap, the molten salt flow rate increment is generated as the molten salt flow rate adjustment amount. The power gap and the molten salt flow rate increment are positively correlated. When the power gap in the power gap sequence is negative, the thermal storage system switches to thermal storage mode. Based on the size of the power gap, the reduction in molten salt flow is generated as the molten salt flow adjustment amount. The power gap and the reduction in molten salt flow are negatively correlated. The increase and decrease in molten salt flow rate are determined based on the specific heat capacity of molten salt, the temperature difference between the inlet and outlet of molten salt, and the heat exchange efficiency of the molten salt-steam heat exchanger.

[0010] In some embodiments, obtaining the molten salt flow correction amount through feedback adjustment based on the difference between the actual output and the target output of the steam turbine specifically includes: A PID controller is used, with the output deviation between the actual output and the target output of the steam turbine as input. When the absolute value of the output deviation is greater than the preset output deviation threshold, the PID controller is activated to obtain the molten salt flow correction amount.

[0011] In some embodiments, the step of constraining and limiting the liquid level in the high-temperature molten salt tank according to a preset liquid level threshold to obtain a liquid level constraint limit specifically includes: The liquid level of the high-temperature molten salt tank is monitored in real time. When the liquid level is lower than the sum of the lower limit of the preset liquid level threshold and the safety margin, the upper limit of the molten salt flow rate after constraint is calculated as the liquid level constraint limit, which is used to limit the heat release power. When the liquid level is higher than the difference between the upper limit of the preset liquid level threshold and the safety margin, the lower limit of the molten salt flow rate increment after constraint is calculated and used as the liquid level constraint limit to limit the thermal storage power.

[0012] In some embodiments, obtaining the final molten salt flow command based on the molten salt flow rate adjustment, the molten salt flow rate correction, and the constraint limit specifically includes: The molten salt flow rate adjustment amount and the molten salt flow rate correction amount are added together to form the initial molten salt flow rate command; The initial molten salt flow rate command is verified and corrected sequentially by the liquid level constraint limit, and the final molten salt flow rate command is output.

[0013] Secondly, the present invention provides a rapid load change control system for a solar thermal power unit based on thermal storage power feedforward, comprising: The dispatch instruction receiving module and the load demand forecasting module are used to receive the sequence of dispatch load instructions in the future time domain and convert them into the turbine demand thermal power sequence based on the unit thermal model. The collector field output prediction module is used to obtain the predicted value of direct normal irradiance in the future time domain, and generate the collector field output power sequence by combining it with the collector field thermodynamic model. The power gap calculation module is used to calculate the difference between the turbine's required thermal power sequence and the collector field's output power sequence to obtain the power gap sequence; The feedforward control module is used to obtain the molten salt flow rate adjustment amount through feedforward adjustment based on the sign and magnitude of the power gap sequence. The feedback control module is used to obtain the molten salt flow correction amount through feedback adjustment based on the difference between the actual output and the target output of the steam turbine. The heat storage management module is used to constrain and limit the liquid level of the high-temperature molten salt tank according to the preset liquid level threshold, obtain the liquid level constraint limit, and obtain the final molten salt flow command based on the molten salt flow adjustment amount, molten salt flow correction amount and constraint limit amount, so as to realize the rapid load change control of the solar thermal unit.

[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 method for rapid load change control of a solar thermal power unit based on thermal storage power feedforward.

[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 method for rapid load change control of a solar thermal power unit based on thermal power feedforward.

[0016] The above technical solution has the following advantages or beneficial effects: Firstly, this invention provides a rapid load change control method for solar thermal power units based on thermal storage power feedforward. By receiving a sequence of dispatch load commands and combining it with meteorological forecast data, the method predicts the future demand for thermal power from the turbine and the output power of the solar collector field in the future time domain, thereby calculating a power gap sequence. Based on the sign and magnitude of this power gap sequence, the feedforward controller adjusts the molten salt pump speed in advance, ensuring that the heat release or storage power of the thermal storage system matches the power gap. This feedforward control mechanism can predict the future power gap trend and proactively implement adjustments the instant the dispatch command is issued, fundamentally avoiding the response lag problem caused by traditional feedback control waiting for the actual power deviation to occur before taking action. Simultaneously, this method uses the difference between the actual turbine output and the target output as a feedback signal to finely adjust the molten salt pump speed, forming a composite control architecture of "feedforward + feedback." Feedforward control responds in advance and reduces lag, while feedback control eliminates prediction errors and ensures accuracy. The two work together to effectively shorten the load change response time and reduce the deviation of key parameters such as steam temperature and pressure during the load change transition. Furthermore, this method avoids the risk of premature depletion of heat storage capacity leading to loss of load-changing capability under continuous load increases by monitoring the high-temperature molten salt tank level in real time and constraining the molten salt flow rate according to a preset level threshold. It also avoids the safety risk of tank overflow caused by excessive molten salt tank level under continuous load decrease conditions. Compared to existing technologies, this application significantly improves the rapid and accurate load-changing response capability and grid dispatch tracking performance of solar thermal power units.

[0017] Secondly, this invention provides a rapid load change control system for solar thermal power units based on thermal storage power feedforward. It achieves advance prediction of power shortages through a dispatch command receiving module, a load demand prediction module, and a collector field output prediction module. Rapid and precise adjustment of molten salt flow is achieved through the coordinated operation of the feedforward control module and the feedback control module. Dynamic constraint management of the high-temperature molten salt tank level is achieved through the thermal storage management module. This system has a clear structure and highly efficient inter-module coordination, significantly shortening the load change response time of the solar thermal power unit, improving the accuracy of grid dispatching, and ensuring the operational safety of the thermal storage system.

[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 a rapid load change control method for a solar thermal power unit based on thermal storage power feedforward, as shown in an embodiment of the present invention. Figure 2 This is a schematic diagram of the rapid load change control system for a solar thermal power unit based on thermal storage power feedforward, 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 feedforward control and feedback control as shown in an embodiment of the present invention; In the diagram, 1. Thermal collector; 2. Steam generator; 3. Steam turbine; 4. High-temperature molten salt tank; 5. Low-temperature molten salt tank; 6. Molten salt pump; 7. Molten salt-steam heat exchanger; 8. Steam bypass valve; 9. Condenser; 10. Dispatch command receiving module; 11. Load demand prediction module; 12. Thermal collector output prediction module; 13. Power deficit calculation module; 14. Feedforward control module; 15. Feedback control module; 16. Heat storage management module; 17. Power sensor; 18. Liquid level sensor; 19. Direct normal irradiance sensor. Detailed Implementation

[0021] 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.

[0022] 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.

[0023] 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.

[0024] Driven by the "dual carbon" goals, dispatchable renewable energy sources, represented by concentrated solar power (CSP), are playing an increasingly important role in peak shaving and frequency regulation in new power systems. Unlike non-dispatchable renewable energy sources such as photovoltaics (PV) and wind power, parabolic trough and tower CSP plants, by configuring large-capacity dual-tank molten salt thermal storage systems (typically with a storage duration of 8-15 hours), can store solar irradiance in the form of high-temperature molten salt thermal energy, releasing it on demand when the grid needs it, achieving 24-hour continuous and controllable power generation. With the rapid growth of CSP installed capacity, grid dispatching agencies have placed higher demands on the load change rate of CSP units, requiring them to complete significant power adjustments within minutes of receiving dispatch instructions to meet the needs of grid load tracking and ancillary services markets. However, the rapid load change control of CSP units faces the technical challenge of strong coupling between the collector field, thermal storage system, and turbine, and existing control methods are insufficient to meet the engineering requirements of rapid and precise load changes.

[0025] The technical challenge of rapid load change in solar thermal power units stems from the strong coupling characteristics among the collector field, the thermal storage system, and the turbine. The output thermal power of the collector field is affected by real-time fluctuations in direct solar irradiance (DNI). Meteorological disturbances such as cloud cover and dust storms can cause a 30% to 50% drop in the collector field's output power within minutes, and this disturbance cannot be actively eliminated through conventional adjustment methods. The molten salt thermal storage system needs to act as a power buffer in real time between the collector field's output and the turbine's load demand: when the load increases, if the collector field's output thermal power is insufficient to meet the increased steam demand of the turbine, the thermal storage system must quickly release heat, pumping high-temperature molten salt to the molten salt-steam heat exchanger to increase the steam thermal power at the turbine inlet; when the load decreases, if the collector field's output exceeds the turbine's reduced steam demand, the thermal storage system must quickly store heat, recovering the excess heat to the high-temperature molten salt tank to prevent deviations in steam parameters. The key actuator in the aforementioned power compensation process is the molten salt pump, whose rotational speed determines the molten salt flow rate, which in turn determines the instantaneous heat release or storage power of the thermal storage system. Because the molten salt pump's rotational speed regulation has mechanical inertia, and the heat exchange process in the molten salt-steam heat exchanger has a time lag, if the control system relies solely on the actual power deviation for feedback regulation, there will inevitably be an unavoidable response lag between the occurrence of the deviation and the completion of the control action. This will cause the steam temperature and pressure parameters to deviate from the design values ​​during load transitions, affecting unit efficiency and equipment safety.

[0026] Several technologies have been explored for thermal energy storage and peak-shaving control in thermal power and solar thermal power plants. Invention application No. 201910313766.8 (Beijing University of Technology) discloses a deep peak-shaving system for thermal power plants. This system utilizes high-temperature molten salt to heat high-pressure feedwater during deep peak-shaving, reducing the steam extraction from the high-pressure turbine cylinder, thereby increasing turbine output and improving the unit's thermal efficiency under low-load conditions. The core idea of ​​this scheme is to optimize the energy configuration of the thermal energy storage system and the thermal system under steady-state conditions, focusing on improving steady-state peak-shaving capabilities. However, it does not establish a predictive and feedforward control mechanism for dynamic load transition processes, and therefore cannot solve the dynamic power mismatch problem that occurs between the output power of the thermal collector and the turbine load demand during load transitions. Invention application No. 202411031322.2 discloses a coal-fired power unit coupled molten salt thermal storage system and control method that balances economic efficiency and rapid load change requirements. By embedding a high-temperature molten salt thermal storage link between the boiler and turbine of the coal-fired power unit, thermal decoupling between the boiler and turbine is achieved. The system switches between thermal storage mode, heat release mode, and isolation mode according to the balance of power supply and demand, improving the load change response rate of the coal-fired power unit. However, this solution is designed for a decoupled scenario at both ends of the boiler and turbine in a coal-fired power unit. The boiler output of a coal-fired power unit can be precisely controlled by adjusting the fuel quantity, and its disturbance sources and control objects are fundamentally different from those of a concentrated solar power (CSP) plant. The output of the solar collector field in a CSP plant is affected by random fluctuations in solar irradiance, making it a complex system with three-terminal coupling. The control architecture of this solution is not suitable for the operating scenario of a CSP plant. Invention application No. 202310041556.4 discloses a turbine-molten salt thermal energy storage parallel deep peak-shaving system. This system simultaneously extracts main steam and reheat steam to heat molten salt, utilizing the sensible heat of the steam to achieve large-capacity energy storage and improve the unit's peak-shaving capacity. However, this scheme focuses on expanding thermal energy storage capacity and increasing peak-shaving depth. It lacks a feedforward control mechanism based on dispatch command prediction, and during load transitions, it still relies on passive feedback adjustment based on actual power deviations, resulting in a response lag problem.

[0027] In the field of solar thermal power plant power prediction, invention application CN202110039006.X discloses a method, system, and equipment for predicting the power of solar thermal power plants. It constructs a complete prediction framework including a molten salt thermal storage heat prediction subsystem, a power demand heat prediction subsystem, and a power generation prediction subsystem. Taking into account factors such as changes in meteorological conditions, the efficiency of the heat collection system, the efficiency of the steam generation system, and the efficiency of the turbine power generation system, it can predict the power generation of the solar thermal power plant under different operating conditions. This scheme has certain advantages in power prediction accuracy, but its design is positioned to provide power prediction information for dispatch centers or operators. The prediction results are presented in the form of information output and do not establish a closed-loop coupling with the control execution layer of the thermal storage system. In other words, this scheme achieves the "prediction" function, but the prediction results cannot directly drive the actions of actuators such as molten salt pumps. There is a gap between the prediction information and the control actions, which cannot achieve prediction-based feedforward control and cannot fundamentally eliminate the response lag under varying loads.

[0028] A comprehensive analysis of the existing technologies reveals a common deficiency: they fail to deeply couple the prediction of dispatch load commands, the prediction of collector power output, and the feedforward control actions of the thermal storage system to form a complete "prediction-feedforward" control closed loop. Existing solutions either only focus on steady-state energy optimization, are only applicable to decoupled scenarios at both ends of coal-fired units, only focus on thermal storage capacity and peak-shaving depth without feedforward control, or only achieve power prediction without establishing a prediction-driven control closed loop. These deficiencies result in the solar thermal power unit's control system passively waiting for actual power deviations after receiving dispatch load change commands before initiating feedback regulation. Typical load change response times reach 5-8 minutes, and steam temperature and pressure parameters can deviate by ±8% during load change transitions, severely restricting the solar thermal power unit's ability to participate in rapid frequency regulation and peak shaving in the power grid. Furthermore, existing solutions generally lack a dynamic constraint management mechanism for thermal storage. Under continuous load increases, the high-temperature molten salt tank level may continuously drop below the lower limit, leading to a loss of load change capability; under continuous load decreases, the high-temperature molten salt tank level may exceed the upper limit, posing a safety risk of overflow. Therefore, there is an urgent need for a rapid load change control method for solar thermal power units that can predict power gaps in advance when dispatch instructions are issued, actively adjust the heat release / storage power of the thermal storage system through feedforward control, and take into account the dynamic constraint management of heat storage, so as to fundamentally solve the response lag problem from the control strategy level.

[0029] Based on the above background, this application provides a rapid load change control method for solar thermal power units based on thermal storage power feedforward. This method receives a sequence of dispatch load commands and combines them with meteorological forecast data to predict the future demand for thermal power from the turbine and the output power from the collector field in the future time domain, and calculates the power gap sequence between the two. Based on this, according to the sign and magnitude of the power gap sequence, the feedforward controller actively and proactively adjusts the speed of the molten salt pump in advance, matching the heat release or storage power of the thermal storage system with the power gap. This achieves advance compensation for the power gap, effectively shortens the load change response time, and improves the rapid and accurate load change response capability of the solar thermal power unit.

[0030] Example: This embodiment provides a rapid load change control method for solar thermal power units based on thermal storage power feedforward. (See also...) Figure 1 This includes the following steps: Step 1: Receive the sequence of scheduling load instructions in the future time domain and convert it into a sequence of turbine demand thermal power based on the unit thermal model.

[0031] In some embodiments, see Figure 2 The method of this invention is applied to a concentrated solar power (CSP) system, including a collector field 1, a steam generator 2, a steam turbine 3, and a molten salt thermal storage system. The molten salt thermal storage system includes a high-temperature molten salt tank 4, a low-temperature molten salt tank 5, a molten salt pump 6 connecting the two, and a molten salt-steam heat exchanger 7. The molten salt-steam heat exchanger 7 is installed in the steam pipeline between the steam generator 2 and the steam turbine 3.

[0032] The heat collection field 1 is connected in sequence to the steam generator 2, the molten salt-steam heat exchanger 7, the steam turbine 3, and the condenser 9. A steam bypass valve 8 is installed on the pipeline between the steam turbine 3 and the condenser 9. The steam generator 2 is connected to the molten salt-steam heat exchanger 7 through the low-temperature molten salt tank 5. The high-temperature molten salt tank 4 is connected to the steam generator 2 and the molten salt-steam heat exchanger 7. A molten salt pump 6 is installed on the pipeline between the high-temperature molten salt tank 4 and the molten salt-steam heat exchanger 7.

[0033] In some embodiments, step 1 specifically includes: Step 1.1: Receive the sequence of scheduling load instructions within the next 5-30 minutes in the time domain, and obtain the efficiency of the steam generation system, the efficiency of the steam turbine, and the power of the auxiliary equipment.

[0034] Specifically, the sequence of load dispatching instructions is issued by the power grid dispatching agency and includes the target power generation that the generating units need to achieve at each time point in the future. It is usually given at fixed time intervals (e.g., one point per minute).

[0035] Specifically, the efficiency of the steam generation system reflects the efficiency of the steam generator 2 in transferring the heat energy of molten salt to the feedwater to generate steam; the efficiency of the steam turbine 3 reflects the efficiency of the steam expanding and doing work in the turbine 3, converting it into mechanical energy and then into electrical energy; the auxiliary power refers to the electrical power consumed by the unit in operation other than the power generated by the turbine 3, such as the power consumption of auxiliary equipment like feedwater pumps and circulating pumps. These parameters can be obtained from the unit design data and performance test reports, and can be corrected based on actual operating data within the normal operating range of the unit.

[0036] Step 1.2: The scheduling load command at each moment is superimposed with the auxiliary machine power, and then combined with the efficiency of the steam generation system and the efficiency of turbine 3 to obtain the thermal power input value required by turbine 3 at the corresponding moment.

[0037] Specifically, based on the first law of thermodynamics, the formula for calculating the required thermal power of turbine 3 is as follows: ; In the formula, This represents the thermal power (MW) required by turbine 3 at time t. This represents the load command value (MW) at time t. Indicates auxiliary power (MW); This represents the efficiency of the steam generation system, with a value ranging from 0.85 to 0.95. This represents the efficiency of turbine 3, with a value ranging from 0.35 to 0.45. These efficiency parameters are calibrated based on unit design data and historical operating data, and can be considered constants within the unit's normal operating range.

[0038] Step 1.3: Arrange the thermal power input values ​​at each moment in chronological order to form the thermal power demand sequence of turbine 3.

[0039] Step 2: Obtain the predicted value of direct normal irradiance in the future time domain, and generate the output power sequence of collector field 1 by combining it with the collector field thermodynamic model.

[0040] In some embodiments, step 2 specifically includes: Step 2.1: Obtain the predicted value of direct normal irradiance in the time domain for the next 5-30 minutes, and obtain the total area of ​​the solar collector, the efficiency of the solar collector, and the heat loss parameters of the pipeline. The efficiency of the solar collector is dynamically determined based on the irradiance and the inlet and outlet temperatures of the molten salt, and the heat loss of the pipeline is determined based on the pipeline length, the insulation material, and the ambient temperature.

[0041] Step 2.2: For the predicted direct normal irradiance value at each moment, multiply it by the total area of ​​the collector and the collector efficiency, and then subtract the heat loss of the pipes to obtain the output power of the collector field 1 at the current moment.

[0042] Specifically, the formula for calculating the output power of collector field 1 is as follows: ; In the formula, This represents the output power (MW) of collector field 1 at time t. This represents the total area of ​​the solar collector (m²). This represents the predicted value of direct normal irradiance at time t (W / m²). The efficiency of the solar collector is expressed in relation to the direct normal irradiance and the molten salt inlet temperature. and molten salt outlet temperature Related; This represents the heat loss in the pipeline (MW), determined based on the pipeline length, insulation material, and ambient temperature. Collector efficiency. Linear or polynomial models can be used for fitting, with typical values ​​ranging from 0.60 to 0.75.

[0043] Step 2.2: Arrange the output power of the heat collection field 1 at each time in chronological order to form the output power sequence of the heat collection field 1.

[0044] In some embodiments, a thermodynamic model characterizing the conversion relationship between electrical power and thermal power is established based on the unit's design parameters and historical operating data. Using this thermodynamic model, the dispatch load command value at each moment is mapped to the thermal power input value required by turbine 3 to generate that electrical power, thereby obtaining the turbine 3's required thermal power sequence corresponding to the dispatch load command sequence.

[0045] Step 3: Calculate the difference between the demand heat power sequence of turbine 3 and the output power sequence of collector field 1 to obtain the power gap sequence.

[0046] In some embodiments, for each corresponding moment in the future time domain, the power demand of the steam turbine 3 is subtracted from the output power of the collector field 1, and the difference is the power gap at that moment. If the difference is positive, it means that the output of the collector field 1 is insufficient to meet the demand of the steam turbine 3; if the difference is negative, it means that the output of the collector field 1 has a surplus. Arranging the differences at all moments in chronological order forms the power gap sequence.

[0047] In some embodiments, the power gap is: ; In the formula, This represents the power deficit (MW) at time t. When When the output of collector field 1 is insufficient to meet the demand of turbine 3, the thermal storage system should operate in heat release mode; when When the output of collector field 1 exceeds the demand of turbine 3, the thermal storage system should operate in thermal storage mode; when Less than the preset power deficit threshold (Typical value is 1%~2% of rated power) Keep the current speed of molten salt pump 6 unchanged and avoid frequent adjustments.

[0048] Step 4: Based on the sign and magnitude of the power gap sequence, obtain the molten salt flow rate adjustment amount through feedforward adjustment.

[0049] In some embodiments, step 4 specifically includes: Step 4.1: When the power gap in the power gap sequence is positive, the thermal storage system switches to the heat release mode. Based on the size of the power gap, the molten salt flow rate increment is generated as the molten salt flow rate adjustment amount. The power gap and the molten salt flow rate increment are positively correlated.

[0050] Step 4.2: When the power gap in the power gap sequence is negative, the thermal storage system switches to thermal storage mode. Based on the size of the power gap, a reduction in molten salt flow rate is generated as the molten salt flow rate adjustment amount. The power gap and the reduction in molten salt flow rate are negatively correlated. The molten salt flow rate increment and the molten salt flow rate reduction are determined based on the molten salt specific heat capacity, the molten salt inlet and outlet temperature difference, and the heat exchange efficiency of the molten salt-steam heat exchanger 7.

[0051] Specifically, based on the power gap First, calculate the required increase in molten salt flow rate. The heat balance equation for molten salt-steam heat exchanger 7 is: ; In the formula, Indicates the required increment in molten salt flow rate (kg / s); This indicates the heat exchange efficiency of the molten salt-steam heat exchanger 7, with a value ranging from 0.90 to 0.98. This indicates the specific heat capacity of molten salt (kJ / (kg·℃)), with a typical value of 1.52 kJ / (kg·℃). This indicates the molten salt side inlet temperature (°C) of molten salt-steam heat exchanger 7. This indicates the molten salt side outlet temperature (°C) of molten salt-steam heat exchanger 7.

[0052] Based on the similarity law of pumps, the calculation formula for the feedforward adjustment of the molten salt pump speed (molten salt flow rate adjustment) is as follows: ; In the formula, This indicates the target molten salt pump 6 rotation speed (r / min) after feedforward adjustment. This indicates the current rotational speed (r / min) of the molten salt pump 6. This represents the current molten salt flow rate (kg / s). The above formula is based on the similarity law of pumps (flow rate is proportional to speed) and is applicable to the operating conditions of molten salt pump 6 operating within the range of 50% to 120% of rated speed.

[0053] Step 5: Based on the difference between the actual output and the target output of turbine 3, the molten salt flow correction amount is obtained through feedback adjustment.

[0054] In some embodiments, step 5 specifically includes: A PID controller is used, with the output deviation between the actual output of turbine 3 and the target output as input. When the absolute value of the output deviation is greater than the preset output deviation threshold, the PID controller is activated to obtain the molten salt flow correction amount.

[0055] Specifically, based on feedforward control, the difference between the actual output and the target output of turbine 3 is used as the feedback signal, and a PID controller is employed to calculate the speed correction (molten salt flow correction) of molten salt pump 6. The output deviation is defined as: ; In the formula, This represents the output deviation (MW) at time t; Indicates the target output (MW); This indicates the actual output power (MW) of turbine 3.

[0056] The PID control law is: ; In the formula, This indicates the speed correction amount (r / min) for molten salt pump 6. This represents the proportionality coefficient, with a value ranging from 0.1 to 1.0. This represents the integral coefficient, with a value ranging from 0.01 to 0.1. The differential coefficients range from 0.01 to 0.1; all three are tuned using the Ziegler-Nichols method based on the unit's thermodynamic characteristics.

[0057] Set output deviation threshold (Typical value is 1% of rated power), when PID feedback control is activated at the specified time; when At this time, feedforward control is the primary method, and the weight of feedback control is reduced to avoid control oscillations caused by frequent adjustments.

[0058] Step 6: Constrain and limit the liquid level of the high-temperature molten salt tank 4 according to the preset liquid level threshold to obtain the liquid level constraint limit amount.

[0059] In some embodiments, step 6 specifically includes: Step 6.1: Monitor the liquid level of the high-temperature molten salt tank 4 in real time. When the liquid level is lower than the sum of the lower limit of the preset liquid level threshold and the safety margin, calculate the upper limit of the molten salt flow rate increment after constraint and use it as the liquid level constraint limit to limit the heat release power.

[0060] Step 6.2: When the liquid level is higher than the difference between the upper limit of the preset liquid level threshold and the safety margin, calculate the lower limit of the molten salt flow rate increment after constraint and use it as the liquid level constraint limit to limit the thermal storage power.

[0061] Specifically, reduce the speed of molten salt pump 6 to the greater of the current speed and the preset minimum speed; at the same time, open the steam bypass valve 8 to directly introduce the excess steam generated by steam generator 2 into condenser 9, so as to prevent all the excess steam from entering the heat storage system and causing the high-temperature molten salt tank 4 to overflow.

[0062] Specifically, when the high-temperature molten salt tank reaches level 4... Below the lower limit of liquid level When the sum of the molten salt flow rate and the preset safety margin is reached, an upper limit must be imposed on the incremental molten salt flow rate to prevent the heat storage capacity from being depleted. The formula for calculating the upper limit of the molten salt flow rate after the restriction is as follows: ; In the formula, This indicates the upper limit of the molten salt flow rate increment after the restriction (kg / s); This indicates the current liquid level (%) in the high-temperature molten salt tank 4. Indicates the lower limit of liquid level (%); This indicates the effective volume (m³) of the high-temperature molten salt tank 4. This indicates the density of molten salt (kg / m³), with a typical value of 1900 kg / m³. This indicates the preset time domain (s).

[0063] Specifically, the above formula is calculated in a preset time domain. The maximum heat release rate corresponding to the available heat storage capacity is taken as the ratio of this maximum heat release rate to the required molten salt flow rate increment. The smaller value in the range is used as the actual control upper limit to ensure that the stored heat will not be depleted within the preset time domain. The limited value is then used as the upper limit. Substituting the values ​​into the speed calculation formula for feedforward regulation, we obtain the constrained feedforward regulation amount for the speed of the molten salt pump 6.

[0064] Step 7: Based on the molten salt flow rate adjustment, molten salt flow rate correction, and constraint limits, the final molten salt flow rate command is obtained to realize rapid load change control of the solar thermal unit.

[0065] In some embodiments, step 7 specifically includes: Step 7.1: Add the molten salt flow rate adjustment amount and the molten salt flow rate correction amount together to form a preliminary molten salt flow rate command; Step 7.2: The initial molten salt flow rate command is verified and corrected sequentially using the liquid level constraint limit, and the final molten salt flow rate command is output.

[0066] Specifically, preliminary molten salt flow instructions It is the sum of the feedforward adjustment and the feedback correction. .

[0067] Through the coordinated operation of the above steps, the rapid load change control method for solar thermal power units provided in this embodiment utilizes feedforward control to compensate for power shortfalls in advance, uses feedback control to eliminate tracking errors, and uses liquid level constraint management to ensure system safety, thereby achieving rapid, accurate, and safe load change response for solar thermal power units.

[0068] Compared to existing feedback control methods that can only passively respond to actual power deviations, this invention establishes a feedforward control mechanism based on dispatch load commands and output predictions from the solar thermal power plant 1. This enables advance compensation for power gaps, reducing the load change response time from 5-8 minutes to 2-3 minutes and the steam parameter deviation from ±8% to within ±3%. This significantly improves the rapid load change response capability and grid dispatch following performance of the solar thermal power unit. At the same time, by introducing heat storage constraint management, the risk of heat storage depletion or overflow is avoided, ensuring the reliable operation of the control system.

[0069] In one embodiment of the present invention, see Figures 2-3 A rapid load change control system for concentrated solar power (CSP) units based on thermal energy storage power feedforward is provided. This system is also applied to CSP power generation systems, including: The dispatch instruction receiving module 10 is used to receive a sequence of dispatch load instructions in the future time domain. The sequence of dispatch load instructions is issued by the power grid dispatching agency and includes the target power generation of the units to be achieved at each time in the future 5-30 minutes.

[0070] The load demand forecasting module 11, whose input is connected to the output of the dispatching instruction receiving module 10, is used to receive the dispatching load instruction sequence in the future time domain and convert it into the demand thermal power sequence of the steam turbine 3 based on the unit thermal model.

[0071] Specifically, the load demand prediction module 11 internally stores a thermodynamic model characterizing the conversion relationship between electrical power and thermal power. This model includes key parameters such as the efficiency of the steam generation system, the efficiency of the steam turbine 3, and the power of auxiliary equipment. The load demand prediction module 11 substitutes the dispatch load command value at each moment into the thermodynamic model to calculate the corresponding thermal power demand of the steam turbine 3, and arranges the calculation results at each moment in chronological order to form a sequence of thermal power demand of the steam turbine 3.

[0072] The collector field output prediction module 12 is used to obtain the predicted value of direct normal irradiance in the future time domain, and generate the output power sequence of collector field 1 by combining the collector field thermodynamic model.

[0073] Specifically, the predicted direct normal irradiance value can be obtained through the direct normal irradiance sensor 19 connected to the collector field output prediction module 12, or it can be received from the weather forecast system through a communication interface. The collector field output prediction module 12 internally stores a collector field thermodynamic model, which includes parameters such as the total area of ​​the collectors, the collector efficiency, and the heat loss of the pipes. The collector field output prediction module 12 substitutes the predicted direct normal irradiance value at each moment into the collector field thermodynamic model to calculate the corresponding output power of collector field 1, and arranges the calculation results at each moment in chronological order to form the output power sequence of collector field 1.

[0074] The power gap calculation module 13 has its input terminals connected to the output terminals of the load demand prediction module 11 and the heat collector output prediction module 12, respectively. It is used to calculate the difference between the demand heat power sequence of the steam turbine 3 and the output power sequence of the heat collector 1 to obtain the power gap sequence.

[0075] Specifically, for each moment in the future time domain, the power gap calculation module 13 subtracts the output power of the heat collector field 1 from the required heat power of the steam turbine 3, and the difference is the power gap at that moment. The power gaps at all moments are arranged in chronological order to form a power gap sequence. When the power gap is positive, it indicates that the output of the heat collector field 1 is insufficient to meet the demand of the steam turbine 3, and the system should operate in heat release mode; when the power gap is negative, it indicates that the output of the heat collector field 1 is sufficient, and the system should operate in heat storage mode.

[0076] The feedforward control module 14, whose input is connected to the output of the power gap calculation module 13, is used to obtain the molten salt flow rate adjustment amount through feedforward adjustment based on the sign and magnitude of the power gap sequence.

[0077] Specifically, the feedforward control module 14 calculates the required molten salt flow rate increment based on the size of the power deficit and the heat transfer characteristics of the molten salt-steam heat exchanger 7. When the power deficit is positive, the feedforward control module 14 calculates a positive molten salt flow rate increment, which is used to increase the flow rate of the molten salt pump 6 to improve the heat release power; when the power deficit is negative, the feedforward control module 14 calculates a negative molten salt flow rate increment (i.e., a reduction in molten salt flow rate), which is used to reduce the flow rate of the molten salt pump 6 to reduce the heat release power or switch to the heat storage mode. The molten salt flow rate adjustment is output as a feedforward control signal.

[0078] In some embodiments, the feedback control module 15 has its input terminal connected to the output terminal of the power sensor 17, and is used to receive the actual output signal of the turbine 3 collected by the power sensor 17, and obtain the molten salt flow correction amount through feedback adjustment based on the difference between the actual output of the turbine 3 and the target output.

[0079] Specifically, the feedback control module 15 compares the actual output of the turbine 3 with the current dispatch load command value (target output), calculates the output deviation, and uses this deviation as input to calculate the molten salt flow correction through the internal PID controller. This correction is used to compensate for the power tracking error caused by factors such as model error and prediction deviation in the feedforward control.

[0080] In some embodiments, the heat storage management module 16 has its input end connected to the output end of the liquid level sensor 18, and is used to receive the liquid level signal of the high-temperature molten salt tank 4 collected by the liquid level sensor 18, constrain and limit the liquid level of the high-temperature molten salt tank 4 according to the preset liquid level threshold, obtain the liquid level constraint limit amount, and obtain the final molten salt flow command according to the molten salt flow adjustment amount, the molten salt flow correction amount and the constraint limit amount, so as to realize the rapid load change control of the solar thermal unit.

[0081] Specifically, the heat storage management module 16 internally stores the upper limit, lower limit, and preset safety margin of the liquid level in the high-temperature molten salt tank 4. When the liquid level is lower than the sum of the lower limit and the safety margin, the heat storage management module 16 calculates the upper limit of the limited molten salt flow rate increment as a liquid level constraint limit to limit the heat release power and prevent the stored heat from being depleted too quickly. When the liquid level is higher than the difference between the upper limit and the safety margin, the heat storage management module 16 generates a liquid level constraint limit to limit the heat storage power, for example, by reducing the speed of the molten salt pump 6 and / or opening the steam bypass valve 8 to introduce excess steam into the condenser 9, thus preventing the high-temperature molten salt tank 4 from overflowing.

[0082] Specifically, the outputs of the feedforward control module 14 and the feedback control module 15 are superimposed and connected to the control terminal of the molten salt pump 6. That is, the molten salt flow rate adjustment output by the feedforward control module 14 and the molten salt flow rate correction output by the feedback control module 15 are superimposed to form a preliminary molten salt flow rate command. The output of the heat storage management module 16 is connected to the limit signal input terminal of the feedforward control module 14, and is used to output the liquid level constraint limit to the feedforward control module 14 to verify and correct the preliminary molten salt flow rate command.

[0083] Finally, the feedforward control module 14 obtains the final molten salt flow command based on the molten salt flow adjustment amount, the molten salt flow correction amount output by the feedback control module 15, and the liquid level constraint limit amount output by the heat storage management module 16. The command is then sent to the control terminal of the molten salt pump 6. By adjusting the speed of the molten salt pump 6, the molten salt flow rate is changed, thereby adjusting the heat release power or heat storage power of the heat storage system, thus completing the rapid load change control of the solar thermal unit.

[0084] Through the coordinated operation of the above modules, the solar thermal power unit rapid load change control system based on thermal storage power feedforward provided in this embodiment can adjust the heat release or thermal storage power of the thermal storage system in advance based on predictive information to compensate for the power gap. At the same time, it can eliminate tracking errors through feedback control and ensure system safety through thermal storage management, thereby realizing rapid, accurate and safe load change response of the solar thermal power unit.

[0085] 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 execute related operations of a rapid load change control method for solar thermal power units based on thermal power feedforward.

[0086] 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 rapid load change control method for solar thermal power units based on thermal power feedforward in this embodiment.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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 rapid load change control method for a solar thermal power unit based on thermal storage power feedforward, characterized in that, Includes the following steps: Receive the sequence of scheduling load instructions in the future time domain and convert it into a sequence of turbine demand thermal power based on the unit's thermal model; Obtain the predicted value of direct normal irradiance in the future time domain, and generate the output power sequence of the collector field by combining it with the collector field thermodynamic model; The power gap sequence is obtained by calculating the difference between the turbine demand power sequence and the collector field output power sequence. The molten salt flow rate adjustment amount is obtained through feedforward regulation based on the sign and magnitude of the power gap sequence. The molten salt flow correction is obtained through feedback adjustment based on the difference between the actual output and the target output of the steam turbine. The liquid level in the high-temperature molten salt tank is constrained and limited according to a preset liquid level threshold, and the liquid level constraint limit is obtained. Based on the molten salt flow rate adjustment, molten salt flow rate correction, and constraint limits, the final molten salt flow rate command is obtained, enabling rapid load change control of the solar thermal unit.

2. The rapid load change control method for solar thermal power units based on thermal storage power feedforward according to claim 1, characterized in that, The process of receiving a sequence of scheduling load instructions in the future time domain, and converting it into a turbine demand thermal power sequence based on the unit's thermal model, specifically includes: Receive the sequence of scheduling load commands within the next 5-30 minutes in the time domain, and obtain the efficiency of the steam generation system, the efficiency of the steam turbine, and the power of the auxiliary equipment; The required thermal power input value of the turbine at each moment is obtained by superimposing the dispatch load command and auxiliary power at each moment, and combining the efficiency of the steam generation system and the turbine efficiency. Arrange the thermal power input values ​​at each moment in chronological order to form the turbine's required thermal power sequence.

3. The rapid load change control method for solar thermal power units based on thermal storage power feedforward according to claim 1, characterized in that, The process of obtaining the predicted direct normal irradiance value in the future time domain and generating the collector field output power sequence by combining it with the collector field thermodynamic model specifically includes: The direct normal irradiance prediction value for the next 5-30 minutes is obtained, and the total area of ​​the solar collector, the efficiency of the solar collector, and the heat loss parameters of the pipeline are obtained. The efficiency of the solar collector is dynamically determined based on the irradiance and the inlet and outlet temperatures of the molten salt, and the heat loss of the pipeline is determined based on the pipeline length, the insulation material, and the ambient temperature. For each moment, the predicted direct normal irradiance is multiplied by the total area of ​​the collector and the collector efficiency, and then the heat loss in the pipes is subtracted to obtain the output power of the collector field at the current moment. The output power of the heat collection field at each moment is arranged in chronological order to form a sequence of heat collection field output power.

4. The rapid load change control method for solar thermal power units based on thermal storage power feedforward according to claim 1, characterized in that, The process of obtaining the molten salt flow rate adjustment amount through feedforward adjustment based on the sign and magnitude of the power gap sequence specifically includes: When the power gap in the power gap sequence is positive, the thermal storage system switches to heat release mode. Based on the size of the power gap, the molten salt flow rate increment is generated as the molten salt flow rate adjustment amount. The power gap and the molten salt flow rate increment are positively correlated. When the power gap in the power gap sequence is negative, the thermal storage system switches to thermal storage mode. Based on the size of the power gap, the reduction in molten salt flow is generated as the molten salt flow adjustment amount. The power gap and the reduction in molten salt flow are negatively correlated. The increase and decrease in molten salt flow rate are determined based on the specific heat capacity of molten salt, the temperature difference between the inlet and outlet of molten salt, and the heat exchange efficiency of the molten salt-steam heat exchanger.

5. The rapid load change control method for solar thermal power units based on thermal storage power feedforward according to claim 1, characterized in that, The step of obtaining the molten salt flow correction amount through feedback adjustment based on the difference between the actual output and the target output of the steam turbine specifically includes: A PID controller is used, with the output deviation between the actual output and the target output of the steam turbine as input. When the absolute value of the output deviation is greater than the preset output deviation threshold, the PID controller is activated to obtain the molten salt flow correction amount.

6. The rapid load change control method for a solar thermal power unit based on thermal storage power feedforward according to claim 1, characterized in that, The step of constraining and limiting the liquid level in the high-temperature molten salt tank according to a preset liquid level threshold to obtain a liquid level constraint limit specifically includes: The liquid level of the high-temperature molten salt tank is monitored in real time. When the liquid level is lower than the sum of the lower limit of the preset liquid level threshold and the safety margin, the upper limit of the molten salt flow rate after constraint is calculated as the liquid level constraint limit, which is used to limit the heat release power. When the liquid level is higher than the difference between the upper limit of the preset liquid level threshold and the safety margin, the lower limit of the molten salt flow rate increment after constraint is calculated and used as the liquid level constraint limit to limit the thermal storage power.

7. The rapid load change control method for solar thermal power units based on thermal storage power feedforward according to claim 1, characterized in that, The process of obtaining the final molten salt flow command based on the molten salt flow adjustment amount, the molten salt flow correction amount, and the constraint limit amount specifically includes: The molten salt flow rate adjustment amount and the molten salt flow rate correction amount are added together to form the initial molten salt flow rate command; The initial molten salt flow rate command is verified and corrected sequentially by the liquid level constraint limit, and the final molten salt flow rate command is output.

8. A rapid load change control system for a solar thermal power unit based on thermal storage power feedforward, characterized in that, The method for rapid load change control of a solar thermal power unit based on thermal storage power feedforward as described in any one of claims 1-7 includes: The dispatch instruction receiving module and the load demand forecasting module are used to receive the sequence of dispatch load instructions in the future time domain and convert them into the turbine demand thermal power sequence based on the unit thermal model. The collector field output prediction module is used to obtain the predicted value of direct normal irradiance in the future time domain, and generate the collector field output power sequence by combining it with the collector field thermodynamic model. The power gap calculation module is used to calculate the difference between the turbine's required thermal power sequence and the collector field's output power sequence to obtain the power gap sequence; The feedforward control module is used to obtain the molten salt flow rate adjustment amount through feedforward adjustment based on the sign and magnitude of the power gap sequence. The feedback control module is used to obtain the molten salt flow correction amount through feedback adjustment based on the difference between the actual output and the target output of the steam turbine. The heat storage management module is used to constrain and limit the liquid level of the high-temperature molten salt tank according to the preset liquid level threshold, obtain the liquid level constraint limit, and obtain the final molten salt flow command based on the molten salt flow adjustment amount, molten salt flow correction amount and constraint limit amount, so as to realize the rapid load change control of the solar thermal unit.

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 rapid load change control method for solar thermal power units based on thermal storage power feedforward 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 rapid load change control method for solar thermal power units based on thermal storage power feedforward as described in any one of claims 1-7.

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