Fused salt system coupling thermal power generating unit frequency modulation optimization control method and device integrating multi-heat-source heat storage mode

Abstract

The invention discloses a frequency modulation optimization control method and device for a fused salt system coupled thermal power generating unit integrating a multi-heat-source heat storage mode, and relates to the field of thermal power generating unit coupled energy storage, and the method comprises the steps: calculating a real-time load deviation delta P based on a power grid frequency modulation signal instruction; when the real-time load deviation delta P is smaller than 0, load reduction control is carried out according to a load reduction strategy; when the real-time load deviation delta P is equal to 0, the current control state of the thermal power generating unit is kept; and when the real-time load deviation delta P is greater than 0, performing load raising control according to a load raising strategy. According to the method, cooperative operation of the fused salt heat storage system and the thermal power generating unit is intelligently regulated and controlled, the load decreasing / increasing strategy is dynamically switched according to the real-time load deviation, during load decreasing, the variable load rate of the thermal power generating unit and the system heat efficiency are remarkably improved, and the power grid frequency modulation capacity is enhanced; and when the load is increased, the molten salt-water supply heat exchanger is combined with the thermal power generating unit for cooperative control, system interference is decoupled, and a control instruction is quickly responded.

Description

Technical Field

[0001] This application relates to the field of thermal power unit coupled energy storage, and in particular to a frequency regulation optimization control method and equipment for a molten salt system coupled with a multi-heat source thermal storage mode for thermal power units. Background Technology

[0002] Coupling various energy storage technologies to flexibly retrofit coal-fired power units can effectively enhance their regulation and support capabilities. Molten salt thermal energy storage systems utilize nitrates and other materials as heat transfer media, achieving the spatial and temporal migration of unit energy storage through the conversion of the heat energy of the working medium with the internal energy of the molten salt, thereby meeting the peak-shaving requirements of the new power system. Compared with other thermal energy storage technologies, molten salt thermal energy storage has advantages such as large capacity, long lifespan, high safety, and system stability. Integrating molten salt thermal energy storage systems can effectively expand the unit's variable load range, achieve a certain degree of thermoelectric decoupling of the unit, and improve the unit's operational safety and flexibility.

[0003] There are three main methods for molten salt thermal storage in coupled coal-fired power units: electric heating, steam extraction heating, and flue gas heating. Among them, flue gas thermal storage systems have high thermal energy quality and good compatibility with molten salt, but system modification is complex, and there are currently no mature application cases in China; electric heating thermal storage is relatively low-cost and has a fast response speed, but the energy conversion efficiency of "electricity-heat-electricity" conversion is low; steam extraction thermal storage has high heat source quality and low system modification cost, but its response speed is limited by the temperature safety of components.

[0004] In summary, existing thermal power units suffer from problems such as low load change rate, low system thermal efficiency, poor grid frequency regulation capability, and susceptibility to interference. Summary of the Invention

[0005] The purpose of this application is to provide a method and equipment for frequency regulation optimization control of a molten salt system coupled with a multi-heat source thermal storage mode for thermal power units. This method can improve the load change rate and system thermal efficiency of thermal power units and enhance the frequency regulation capability of the power grid when the load is reduced; and decouple system interference and quickly respond to control commands when the load is increased.

[0006] To achieve the above objectives, this application provides the following solution:

[0007] Firstly, this application provides a frequency regulation optimization control method for a molten salt system coupled with a thermal power unit, integrating a multi-heat source thermal storage mode. This method is applied to a multi-heat source molten salt thermal storage system, which includes at least: an extraction steam thermal storage heat exchanger, an electric heating heat exchanger, and a molten salt-feedwater heat exchanger. The control method includes: acquiring a grid frequency regulation signal command; the grid frequency regulation signal command includes: the grid secondary frequency regulation power and the real-time load of the thermal power unit; based on the grid... The frequency modulation signal command calculates the real-time load deviation ΔP; when the real-time load deviation ΔP is less than 0, load reduction control is performed according to the load reduction strategy; the load reduction strategy is a control strategy that controls the combined thermal power unit of extraction steam storage heat exchanger and electric heating heat exchanger to reduce the load in a coordinated manner; when the real-time load deviation ΔP is equal to 0, the current control state of the thermal power unit is maintained; when the real-time load deviation ΔP is greater than 0, load increase control is performed according to the load increase strategy; the load increase strategy is a control strategy that controls the combined thermal power unit of molten salt-feedwater heat exchanger to increase the load in a coordinated manner.

[0008] Secondly, this application 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 above-described method for frequency regulation optimization control of molten salt system coupled with integrated multi-heat source thermal storage mode for thermal power units.

[0009] According to the specific embodiments provided in this application, the following technical effects are disclosed:

[0010] This application acquires grid frequency regulation signal commands and calculates the real-time load deviation ΔP based on these commands. When the real-time load deviation ΔP is less than 0, load reduction control is implemented according to a load reduction strategy. When the real-time load deviation ΔP equals 0, the current control state of the thermal power unit is maintained. When the real-time load deviation ΔP is greater than 0, load increase control is implemented according to a load increase strategy. This application intelligently regulates the coordinated operation of the molten salt thermal storage system and the thermal power unit, dynamically switching between load reduction and increase strategies based on the real-time load deviation. During load reduction, it fully leverages the dual advantages of fast response speed of the electric heating heat exchanger and high efficiency of the extraction steam thermal storage heat exchanger. By optimizing the power allocation of the two thermal storage methods, it significantly improves the load change rate of the thermal power unit and the system thermal efficiency, enhancing the grid frequency regulation capability. During load increase, through coordinated control of the molten salt-feedwater heat exchanger and the thermal power unit, it distinguishes the power increments of the thermal power unit and the thermal storage system, modifies load commands, decouples system interference, and achieves coordination between the molten salt thermal storage and the thermal power unit, enabling rapid response to control commands. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a flowchart illustrating a frequency regulation optimization control method for a molten salt system coupled with a multi-heat source thermal storage mode, provided in an embodiment of this application.

[0013] Figure 2 The system structure diagram of the multi-molten salt thermal storage system coupled with the thermal power unit provided in the embodiments of this application is shown.

[0014] Figure 3 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application. Detailed Implementation

[0015] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0016] To balance the improvement of load change rate and system energy efficiency of molten salt thermal storage systems coupled with coal-fired power units, flexible adjustment and control strategies can be implemented throughout the entire process of molten salt systems coupled with thermal power units under different thermal storage methods and application scenarios. For control objectives such as rapid load tracking or stable molten salt outlet temperature, the coupling methods are limited to frequency regulation and peak shaving schemes for molten salt thermal storage coupled with coal-fired power units under a single heat source. Research on collaborative control schemes for molten salt thermal storage systems integrating multiple heat source thermal storage modes is scarce. Furthermore, existing control strategies are designed relatively independently, failing to consider the complementary coupling characteristics of the molten salt thermal storage system and the thermal power unit's Coordination Control System (CCS), and lacking a systematic control scheme throughout the entire load increase and decrease process.

[0017] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] Example 1, as Figures 1-2As shown, this embodiment provides a frequency regulation optimization control method for a molten salt system coupled with a thermal power unit that integrates multiple heat source thermal storage modes. The method is applied to a multi-heat source molten salt thermal storage system, which includes at least: a steam extraction thermal storage heat exchanger (steam-molten salt heat exchanger), an electric heating heat exchanger, and a molten salt-feedwater heat exchanger. The control method includes the following steps.

[0019] S1. Obtain the power grid frequency regulation signal instruction; the power grid frequency regulation signal instruction includes: power grid secondary frequency regulation power (power grid secondary frequency regulation signal AGC instruction) and real-time load of thermal power units.

[0020] S2. Calculate the real-time load deviation ΔP based on the power grid frequency regulation signal command.

[0021] Furthermore, the calculation formula for the real-time load deviation ΔP is as follows.

[0022] ΔP=P ref -P G .

[0023] In the formula, ΔP is the real-time load deviation; P ref P is the secondary frequency regulation power of the power grid; G This represents the real-time load of the thermal power unit.

[0024] S3. When the real-time load deviation ΔP is less than 0, load reduction control is performed according to the load reduction strategy; the load reduction strategy is a control strategy that controls the combined thermal power unit of extraction steam storage heat exchanger and electric heating heat exchanger to reduce the load in a coordinated manner.

[0025] Furthermore, the load reduction strategy specifically includes the following steps.

[0026] When |ΔP|≤P emax At this time (when the capacity of the electric heating heat exchanger can meet the unit's rapid load reduction requirements), the power grid frequency is regulated only through the electric heating heat exchanger. The power control command of the multi-heat source molten salt thermal storage system is as follows.

[0027]

[0028] Among them, P emax P is the rated power of the electric heating heat exchanger. e P represents the real-time power of the electric heating heat exchanger. s This represents the real-time power of the extraction steam heat exchanger.

[0029] When P emax <|ΔP|<P emax +P smaxWhen the AGC command issued by the power grid fluctuates significantly, the power grid frequency is regulated at full load through the electric heating heat exchanger, and the extraction steam storage heat exchanger regulates |ΔP|-P. emax Partial grid frequency regulation is implemented (at this time, the capacity of the single electric heating molten salt energy storage system is insufficient, and the extraction steam heat exchanger reduces the steam flow entering the turbine to do work by rapidly extracting the main steam flow. During this process, the electric heating heat exchanger operates at full load to maximize the unit's load reduction rate). The power control commands for the multi-heat source molten salt thermal energy storage system are as follows.

[0030]

[0031] When |ΔP|≥P emax +P smax At that time, the power grid frequency is regulated at full load through both the electric heating heat exchanger and the extraction steam storage heat exchanger. The power control command of the multi-heat source molten salt thermal storage system is as follows.

[0032]

[0033] When |ΔP| is adjusted to 0, the electric heating heat exchanger and the extraction steam storage heat exchanger gradually shut down, while retaining a margin for the next load reduction action.

[0034] In practical applications, when |ΔP|≥P emax +P smax At this time, the thermal power unit operates according to the original coordinated control system (the main control variables are feedwater flow, main steam valve opening, and coal feed rate). The multi-molten salt thermal storage system compensates for the insufficient capacity of the thermal power unit itself. When the thermal power unit can track the unit load command, the electric heating heat exchanger and the extraction steam thermal storage heat exchanger gradually withdraw, reserving operational margin for the next load reduction command. The main objective of the load reduction strategy is to match different thermal storage systems according to the incremental mode of the AGC command and set the power command P of the electric heating thermal storage system. e Power command P for extraction steam heat exchanger s .

[0035] Optionally, the rated capacity setting process for the electric heating heat exchanger and the extraction steam storage heat exchanger is as follows: the rated power of the electric heating heat exchanger is P. emax The rated power is directly determined by the electric power of the electric heating heat exchanger; the rated power of the extraction steam storage heat exchanger is P. smax This value is determined by the maximum extraction steam flow rate. During the main steam extraction process, excessive steam flow can lead to problems such as reheater temperature exceeding limits and turbine axial thrust imbalance, which can seriously affect the safe operation of the thermal power unit. Therefore, it is necessary to limit the unit's extraction steam flow rate, setting the main steam extraction flow rate to no more than 15% of the rated extraction steam flow rate. The rated power P of the extraction steam heat storage heat exchanger is determined based on the unit load change under the maximum extraction steam flow rate of the thermal power unit.smax .

[0036] Furthermore, the extraction steam heat exchanger affects |ΔP|-P emax Partial grid frequency regulation is implemented, specifically including: the extraction steam heat exchanger uses a proportional-derivative-integral (PID) controller to adjust the opening of the extraction steam valve, thereby controlling the steam flow rate to affect |ΔP|-P. emax Frequency regulation of the power grid is partially implemented.

[0037] Furthermore, the load reduction control includes: controlling the extraction steam storage heat exchanger to extract high-temperature main steam based on the load reduction strategy, combining the electric heating heat exchanger to heat the low-temperature molten salt to a first preset temperature and then store it, and adjusting the output of the steam flow of the extraction steam storage heat exchanger to complete the coordinated load reduction control of the high-pressure heater and the electric heating heat exchanger unit.

[0038] Optionally, the first preset temperature is 500℃.

[0039] In practical applications, when the real-time load deviation ΔP is less than 0, it is the heat storage process of the system. The thermal power unit needs to perform load reduction operation. At this time, the unit coordinated control system of extraction steam heat storage heat exchanger and electric heating heat exchanger, and the multi-heat source molten salt heat storage system jointly completes the rapid reduction of the unit's on-grid load by controlling the extraction steam flow and the load of the electric heating heat exchanger.

[0040] Specifically, when a thermal power unit receives a load reduction instruction, the multi-molten salt thermal storage system can, on the one hand, extract some high-temperature main steam to heat the 290°C low-temperature molten salt from the cold salt tank to 500°C and store it in the high-temperature tank, thereby reducing the steam flow entering the turbine to do work and reducing the unit's real-time output; on the other hand, it can divert some electricity to heat the molten salt to reduce the unit's grid-connected electricity consumption. Both thermal storage methods have their advantages. The steam extraction thermal storage scheme has high system efficiency and good economic performance, while the electric heating scheme has a simple system and high flexibility. The integrated method of steam extraction + electric heating can give full play to the advantages of each.

[0041] S4. When the real-time load deviation ΔP is equal to 0, maintain the current control state of the thermal power unit.

[0042] S5. When the real-time load deviation ΔP is greater than 0, load increase control is performed according to the load increase strategy; the load increase strategy is a control strategy for coordinating the increase of load of the molten salt-feedwater heat exchanger and the combined thermal power unit.

[0043] Furthermore, the load increase strategy specifically includes the following steps.

[0044] Obtain the power increment; the power increment is the throttling flow rate D. w The input throttling increment model is used for calculation.

[0045] The frequency regulation power ΔP of the thermal power unit is calculated based on real-time load deviation and power increment. n Thermal power unit frequency regulation power ΔP n The calculation formula is as follows.

[0046] ΔP n =ΔP+ΔN e .

[0047] The feedwater flow rate is adjusted by controlling the real-time power of the molten salt-feedwater heat exchanger, and the load of the thermal power unit is adjusted based on the frequency regulation power of the thermal power unit.

[0048] When ΔP n When the value is 0, the molten salt-feedwater heat exchanger gradually shuts down, while retaining a margin for the next load increase.

[0049] In practical applications, the load increase strategy based on power increment mode is as follows.

[0050] 1) Identification of the throttling power increment model.

[0051] Select operating data of the molten salt thermal storage system under different operating conditions (mainly including throttling flow rate Dw, unit power increment ΔN). e Based on the data, the relationship between power increment and throttling flow rate was fitted, and the throttling power increment model of the molten salt thermal storage system was identified as follows.

[0052] ΔN e =f(D w ).

[0053] In the formula: f(·) represents the relative functional relationship, which can be fitted as a second-order inertial element.

[0054] Optionally, the expression for the throttling increment model is as follows.

[0055]

[0056] 2) Improved acquisition of power command signals for thermal power units.

[0057] The AGC command is issued as a complete load command to the CCS of the thermal power unit, and its feedback command is issued by the real-time load P. G The power increment ΔN calculated by the throttling increment model e This configuration is used to decouple the mutual interference between the molten salt thermal storage system and the boiler-turbine CCS system. The thermal power unit command signal ΔP during load increase... n The calculation is as follows.

[0058] ΔP n =ΔP+ΔN e .

[0059] The original command signal for the thermal power unit was ΔP = Pref -P G This patented design aims to decouple the power increment caused by the high-pressure heater throttling as much as possible under increased load conditions. Therefore, the power unit command signal needs to be increased by the power increment ΔN caused by throttling on top of the original ΔP. e .

[0060] Furthermore, the construction process of the throttling increment model is as follows.

[0061] 1) Select historical operating data of the multi-heat source molten salt thermal storage system under different operating conditions; the historical operating data includes: throttling flow rate D w and unit power increment ΔN e .

[0062] 2) For the throttling flow rate D w and unit power increment ΔN e A linear fit was performed on the relationship to obtain the throttling power increment model.

[0063] Furthermore, the throttling power increment model is a second-order inertial element.

[0064] Furthermore, the load increase control includes: controlling the molten salt-feedwater heat exchanger to heat the feedwater to a second preset temperature using high-temperature molten salt based on the load increase strategy, and adjusting the turbine power generation output by controlling the feedwater flow rate, thereby completing the coordinated load increase control of the molten salt-feedwater heat exchanger combined unit.

[0065] The load reduction control (heat release) process is mainly based on a power increment model-based thermal-storage coordinated load optimization control strategy to achieve coordinated control of the molten salt-feedwater heat exchanger and the CCS system. By distinguishing the power increment portion undertaken by the thermal power unit's coordinated control system from the power increment portion undertaken by the molten salt thermal storage system, and then modifying the unit load command signal, the interference of the two systems operating simultaneously is decoupled, maximizing the coordinated regulation effect of both, responding more quickly to grid AGC commands, and eliminating mutual interference between the two control systems.

[0066] In practical applications, the load increase strategy control process is as follows.

[0067] The multi-molten salt thermal energy storage control system changes the output power of the thermal power unit by controlling the feedwater flow through the molten salt thermal energy storage system. The system has good dynamic characteristics, therefore a simple and reliable PI controller is used for feedwater flow control. The controller input is the deviation ΔP between the AGC command and the actual load. In the initial stage of load change, the load deviation is large, and the molten salt thermal energy storage system controls a larger feedwater diversion flow to reduce the steam extraction flow used for heating the feedwater, quickly increasing the unit load. As the load change process progresses, the load deviation gradually decreases, and the feedwater control of the molten salt thermal energy storage system also gradually decreases until the unit load can stably track the AGC command. At this point, the molten salt thermal energy storage system exits control and regains its regulating capacity in preparation for the next frequency regulation operation.

[0068] Optionally, the second preset temperature is 321.8°C.

[0069] In practical applications, when ΔP > 0, it is the heat release process of the system. The thermal power unit needs to perform load increase operation. At this time, the feedwater of the high-pressure heater control diversion section is heated by hot molten salt. The unit coordination control system realizes the rapid increase of the unit's on-grid load.

[0070] Specifically, during the heat release process, the high-temperature molten salt heats a portion of the feedwater at the deaerator outlet to 321.8℃, which then merges with the feedwater from the original high-pressure heater outlet before entering the boiler economizer. Because the multi-molten salt thermal storage system undertakes part of the feedwater heating task, the feedwater flow rate into the high-pressure heater decreases, the feedwater saturation temperature inside the high-pressure heater rises, and the steam-side pressure inside the heater increases. This results in a decrease in the extraction steam differential pressure and a reduction in the extraction steam flow rate, increasing the turbine's power output and thus achieving the goal of rapid load increase. Simultaneously, compared to the traditional high-pressure heater throttling scheme, the molten salt thermal storage system heats the throttled feedwater before merging it into the economizer inlet, reducing the disturbance impact of direct throttling on the boiler-side feedwater.

[0071] In practical applications, multi-heat-source molten salt thermal storage systems utilize the steam from thermal power units (coal-fired units) and the electricity generated by the units as the energy source for low-temperature molten salt. When load reduction is required, the excess heat and electricity inside the thermal power unit are stored as the heat energy of the molten salt to achieve rapid load reduction of the thermal power unit. During the heat release process, the high-temperature molten salt releases its heat by heating part of the deaerator feedwater, while rapidly increasing the output power of the thermal power unit.

[0072] The technical effects of this application are as follows.

[0073] This application addresses the load shifting process of molten salt thermal storage coupled with thermal power units. It designs two strategies: a load-reducing thermal storage control based on AGC command incremental mode matching and a coordinated load-increasing optimization control strategy based on a power increment model (load-reducing strategy and load-increasing strategy). Through intelligent regulation of the coordinated operation of the molten salt thermal storage system and the thermal power unit, the load-reducing / increasing strategies are dynamically switched based on real-time load deviations. This fully leverages the dual advantages of the fast response speed of the electric heating heat exchanger and the high efficiency of the extraction steam thermal storage heat exchanger. When the unit needs to reduce load, the fast response of the electric heating heat exchanger and the large capacity of the extraction steam thermal storage heat exchanger are used to store excess heat and electricity in the molten salt. When the load increases, the molten salt thermal storage system heats the feedwater to release heat, increasing the unit's load change rate. By optimizing the power allocation of the two thermal storage methods, the load change rate of the thermal power unit and the system thermal efficiency are significantly improved, enhancing the grid's frequency regulation capability. Furthermore, the heat release control strategy considering the power increment model can decouple the mutual influence between the thermal power unit's coordinated control system and the molten salt thermal storage system.

[0074] Example 2: This application also provides a computer device, which may be a server or a terminal, and its internal structure diagram may be as follows. Figure 3 As shown, this computer device includes a processor, memory, input / output interfaces (I / O), and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores and processes data. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communicating with external terminals via a network connection. When the computer program is executed by the processor, it implements the methods described above.

[0075] Those skilled in the art will understand that Figure 3 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0076] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0077] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A frequency regulation optimization control method for a molten salt system coupled with a multi-heat source thermal power unit, characterized in that, The frequency regulation optimization control method for a molten salt system coupled with a multi-heat source thermal power unit, integrating a multi-heat source molten salt thermal storage mode, is applied to such a system. The multi-heat source molten salt thermal storage system includes at least: an extraction steam thermal storage heat exchanger, an electric heating heat exchanger, and a molten salt-feedwater heat exchanger. The control method includes: Acquire power grid frequency regulation signal instructions; the power grid frequency regulation signal instructions include: power grid secondary frequency regulation power and real-time load of thermal power units; Calculate the real-time load deviation ΔP based on the power grid frequency regulation signal command; When the real-time load deviation ΔP is less than 0, load reduction control is performed according to the load reduction strategy; the load reduction strategy is a control strategy that controls the extraction steam storage heat exchanger and the electric heating heat exchanger in conjunction with the thermal power unit to reduce the load in a coordinated manner. When the real-time load deviation ΔP is equal to 0, the current control state of the thermal power unit is maintained; When the real-time load deviation ΔP is greater than 0, the load increase control is carried out according to the load increase strategy; the load increase strategy is a control strategy for coordinating the increase of load of the molten salt-feedwater heat exchanger and the thermal power unit.

2. The frequency regulation optimization control method for molten salt systems coupled with thermal power units using integrated multi-heat source thermal storage modes according to claim 1, characterized in that, The formula for calculating the real-time load deviation ΔP is as follows: ΔP=P ref -P G ; In the formula, ΔP is the real-time load deviation; P ref P is the secondary frequency regulation power of the power grid; G This represents the real-time load of the thermal power unit.

3. The frequency regulation optimization control method for molten salt systems coupled with thermal power units using integrated multi-heat source thermal storage modes according to claim 1, characterized in that, The load reduction strategy specifically includes: When |ΔP|≤P emax When the power grid frequency is regulated solely through the electric heating heat exchanger, the power control commands for the multi-heat source molten salt thermal storage system are as follows: Among them, P emax P is the rated power of the electric heating heat exchanger. e P represents the real-time power of the electric heating heat exchanger. s This refers to the real-time power of the extraction steam heat storage heat exchanger. When P emax <|ΔP|<P emax +P smax At that time, the power grid frequency is regulated at full load through the electric heating heat exchanger, and the extraction steam storage heat exchanger is used for |ΔP|-P emax For partial grid frequency regulation, the power control commands for the multi-heat-source molten salt thermal storage system are as follows: When |ΔP|≥P emax +P smax At that time, both the electric heating heat exchanger and the extraction steam storage heat exchanger are operated at full load for grid frequency regulation. The power control commands for the multi-heat source molten salt thermal storage system are as follows: When |ΔP| is adjusted to 0, the electric heating heat exchanger and the extraction steam storage heat exchanger gradually shut down, while retaining a margin for the next load reduction action.

4. The frequency regulation optimization control method for molten salt systems coupled with thermal power units using integrated multi-heat source thermal storage modes according to claim 1, characterized in that, Extraction steam heat exchanger for |ΔP|-P emax Partial grid frequency regulation includes: The extraction steam heat exchanger uses a proportional-derivative-integral controller to adjust the opening of the extraction steam valve, thereby controlling the steam flow rate and affecting |ΔP|-P. emax Frequency regulation of the power grid is partially implemented.

5. The frequency regulation optimization control method for molten salt systems coupled with thermal power units using integrated multi-heat source thermal storage modes according to claim 1, characterized in that, The load increase strategy specifically includes: Obtain the power increment; the power increment is the throttling flow rate D. w Calculated using the input throttling increment model; The frequency regulation power ΔP of the thermal power unit is calculated based on real-time load deviation and power increment. n Thermal power unit frequency regulation power ΔP n The calculation formula is as follows: ΔP n =ΔP+ΔN e ; The feedwater flow rate is adjusted by controlling the real-time power of the molten salt-feedwater heat exchanger, and the load of the thermal power unit is adjusted based on the frequency regulation power of the thermal power unit. When ΔP n When the value is 0, the molten salt-feedwater heat exchanger gradually shuts down, while retaining a margin for the next load increase.

6. The frequency regulation optimization control method for molten salt systems coupled with thermal power units using integrated multi-heat source thermal storage modes according to claim 5, is characterized in that... The process of constructing the throttling increment model is as follows: Historical operating data of the multi-heat-source molten salt thermal storage system under different operating conditions were selected; the historical operating data included: throttling flow rate D. w and unit power increment ΔN e ; For the throttling flow rate D w and unit power increment ΔN e A linear fit was performed on the relationship to obtain the throttling power increment model.

7. The frequency regulation optimization control method for molten salt systems coupled with thermal power units using integrated multi-heat source thermal storage modes according to claim 5, characterized in that, The throttling power increment model is a second-order inertial element.

8. The frequency regulation optimization control method for molten salt systems coupled with thermal power units using integrated multi-heat source thermal storage modes according to claim 1, characterized in that, The load reduction control includes: controlling the extraction steam storage heat exchanger to extract high-temperature main steam based on the load reduction strategy, combining the electric heating heat exchanger to heat the low-temperature molten salt to a first preset temperature and then store it, and adjusting the output of the steam flow of the extraction steam storage heat exchanger to complete the coordinated load reduction control of the high-pressure heater and the electric heating heat exchanger unit.

9. The frequency regulation optimization control method for molten salt systems coupled with thermal power units using integrated multi-heat source thermal storage modes according to claim 1, characterized in that, The load increase control includes: controlling the molten salt-feedwater heat exchanger to heat the feedwater to a second preset temperature using high-temperature molten salt based on the load increase strategy, and adjusting the turbine power generation output by controlling the feedwater flow rate, thereby completing the coordinated load increase control of the molten salt-feedwater heat exchanger unit.

10. A computer device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to implement the frequency regulation optimization control method for molten salt system coupled thermal power unit with integrated multi-heat source thermal storage mode as described in any one of claims 1-9.

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