Preheating control method and device for molten salt groove type heat collector

Abstract

The invention relates to the technical field of heat collector control, in particular to a molten salt groove type heat collector preheating control method and device.The method comprises the steps that before a heat collecting system is started, initial preheating execution parameters of each heat collector are determined on the basis of molten salt injection characteristics, and corresponding heating assemblies are controlled according to the initial preheating execution parameters to conduct initial heating on the heat collectors; in the injection process, state difference vectors corresponding to all the heat collectors are monitored in real time; the state difference vector represents the difference value of each state parameter between the input end and the output end of the heat collector; the state difference vector comprises a temperature difference, a pressure difference and a flow difference; in response to the condition that the difference value of any state parameter exceeds a corresponding preset fluctuation range, inputting the state difference vector into a preset preheating adjustment model to obtain a preheating adjustment factor; and correcting the initial preheating execution parameter based on the preheating regulation factor to obtain a real-time preheating execution parameter, and controlling a corresponding heating assembly to heat the heat collector in real time according to the real-time preheating execution parameter. The system stability can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of collector control, and in particular to a molten salt tank collector preheating control method and device. BACKGROUND

[0002] As a kind of high-efficiency solar thermal utilization equipment, molten salt tank collector plays an important role in solar thermal power generation system. Its working principle is to focus sunlight on the collector, so that the molten salt absorbs heat and converts light energy into heat energy, thereby providing a high-temperature heat source for subsequent power generation or heating process.

[0003] The existing molten salt tank collector preheating control method mostly adopts unified power heating or control mode based on a single temperature threshold, only triggers preheating stop by setting a fixed temperature target (such as 260℃), does not set targeted initial preheating parameters in combination with the structural differences of different collectors, and cannot adjust the heating strategy in real time based on the state parameter fluctuations of the input and output ends when the molten salt is injected, for example, when the collector output end temperature meets the standard but the flow drops sharply due to local blockage, the existing control method is difficult to identify the potential frozen blockage risk in time, thereby causing problems such as local pipe frozen blockage, abnormal pressure rise and valve jamming. SUMMARY

[0004] The present application provides a molten salt tank collector preheating control method and device that can improve system stability and reduce fault risk, which can effectively solve the problems in the background art.

[0005] To achieve the above purpose, in a first aspect, the present application provides a molten salt tank collector preheating control method, comprising: Before the start of the collector system, based on the molten salt injection characteristics, determine the initial preheating execution parameters of each collector, and control the corresponding heating components to initially heat the collector according to the initial preheating execution parameters; During the injection process, real-time monitor the state difference vector of each collector; the state difference vector represents the difference of each state parameter between the input and output ends of the collector; the state difference vector includes temperature difference, pressure difference and flow difference; In response to the difference of any state parameter exceeding the corresponding preset fluctuation range, input the state difference vector into the preset preheating adjustment model to obtain a preheating adjustment factor; Based on the preheating adjustment factor, modify the initial preheating execution parameters to obtain real-time preheating execution parameters, and control the corresponding heating components to heat the collector in real time according to the real-time preheating execution parameters.

[0006] In a possible design, in combination with the first aspect, before the start of the collector system, based on the molten salt injection characteristics, the initial preheating execution parameters of each collector are determined, comprising: obtaining a plurality of groups of heat collector state features, each group of heat collector state features corresponding to a plurality of heat collectors in the heat collection system, wherein each heat collector is configured with a set of heating components; based on the molten salt injection feature and the heat collector state feature of each heat collector, respectively, performing a freeze risk assessment on each heat collector to obtain a freeze risk index corresponding to each heat collector; for each heat collector, according to the corresponding freeze risk index and the performance parameters of the heating components, mapping in a preset preheating strategy library to obtain initial preheating execution parameters corresponding to the heating components.

[0007] In combination with the first aspect, in a possible design, the molten salt injection feature includes molten salt injection temperature, molten salt injection pressure, and molten salt freezing point.

[0008] In combination with the first aspect, in a possible design, the heat collector state feature includes pipe length, pipe inner diameter, and initial pipe temperature.

[0009] In combination with the first aspect, in a possible design, the performance parameters of the heating components include at least maximum heating power, heating efficiency, temperature control accuracy, and response time.

[0010] In combination with the first aspect, in a possible design, the strategies in the preset preheating strategy library include staged preheating strategies, dynamic adjustment preheating strategies, and safety redundancy preheating strategies.

[0011] In combination with the first aspect, in a possible design, the setting of the preset fluctuation range is based on molten salt physical property parameters, heat collector structure and operating parameter limits, historical operation data and experimental verification results, heating component performance, and system safety redundancy.

[0012] In combination with the first aspect, the initial preheating execution parameters include at least heating power, heating voltage, target temperature, and heating duration.

[0013] In combination with the first aspect, the input end and the output end of the heat collector are each provided with a temperature sensor, a flow sensor, and a pressure sensor.

[0014] On the other hand, the application also provides a molten salt tank type heat collector preheating control device, comprising: a support mechanism for insulating and supporting the heat collector metal pipe; an initial preheating execution module for determining initial preheating execution parameters of each heat collector based on molten salt injection features before starting the heat collection system, and controlling the corresponding heating components to initially heat the heat collector according to the initial preheating execution parameters; A state difference monitoring module is configured to collect and calculate a state difference vector between the input end and the output end of each collector in real time during the molten salt injection process, the state difference vector including at least a temperature difference, a pressure difference and a flow difference; A preheating adjustment calculation module is configured to input the state difference vector to a preheating adjustment model and output a preheating adjustment factor when the difference of any state parameter exceeds the corresponding preset fluctuation range. A real-time preheating execution module is configured to correct the initial preheating execution parameter according to the preheating adjustment factor, generate a real-time preheating execution parameter, and control the corresponding heating component to heat the collector in real time.

[0015] In combination with the second aspect, the support mechanism includes at least a driving support and a clamp support. The driving support is provided with a first insulation component for realizing insulation between the driving support and the collector metal pipe. The clamp support is provided with a second insulation component for realizing insulation between the clamp support and the collector metal pipe. The first insulation component and the second insulation component are both made of insulation material.

[0016] In combination with the second aspect, the first insulation component includes at least an insulation pad, an insulation bolt sleeve and an insulation gasket. The insulation pad is installed between the support top seat and the support bottom seat of the driving support. The insulation bolt sleeve is adapted to the screw rod of the driving support and is sleeved on the outside of the screw rod. The insulation gasket is arranged on the side of the nut of the driving support.

[0017] In combination with the second aspect, the second insulation component includes at least a heat insulation piece, an insulation sleeve and an insulation sleeve group. The heat insulation piece has the same inner diameter as the outer diameter of the collector metal pipe, and has a width equal to the spacing between two adjacent collector metal pipes, and is fixed to the collector metal pipe through a clamp structure. The insulation sleeve is sleeved on the outside of the latch of the clamp support. The insulation sleeve group is installed at the spring plate of the clamp support.

[0018] The technical solution of the present application can achieve the following technical effects: Before the start of the heat collection system, the initial preheating execution parameters of each heat collector are determined based on the molten salt injection characteristics, and the corresponding heating components are controlled to perform initial heating; the individual differences of the heat collectors are considered, so that the initial preheating is more in line with the actual situation, which helps to improve the preheating effect and efficiency; during the injection process, the state difference vector of each heat collector is monitored in real time, which covers the temperature difference, pressure difference and flow difference between the input end and the output end of the heat collector; by comprehensively monitoring the difference values of these key state parameters, the changes in the running state of the heat collector can be grasped in time; when the difference value of any state parameter exceeds the corresponding preset fluctuation range, the state difference vector is input into the preset preheating adjustment model, so that abnormal conditions such as the sudden drop of flow caused by local blockage of the heat collector output end temperature reaching the standard can be found in time, the potential frozen blockage risk can be effectively identified, and the serious consequences such as local frozen blockage of pipeline, abnormal rise of pressure and valve jam caused by the existing control method difficult to find such problems in time are avoided; the preheating adjustment factor obtained based on the preheating adjustment model is used to modify the initial preheating execution parameters to obtain real-time preheating execution parameters, and the corresponding heating components are controlled to heat the heat collector in real time; so that the heating strategy can be dynamically adjusted according to the actual running state of the heat collector, the flexibility and accuracy of the control are improved, and the heat collector can maintain good preheating effect under different working conditions, ensuring the stable operation of the whole photo-thermal power generation system. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The flowchart of the present application is shown in the figure. Figure 2 The heating circuit diagram of the molten salt tank type heat collector system is shown in the figure. Figure 3 The heating circuit diagram of the molten salt tank type heat collector system is shown in the figure. Figure 4 The structure schematic diagram of the driving support is shown in the figure. Figure 5 The structure schematic diagram of the hoop support is shown in the figure. Figure 6 The structure schematic diagram of the insulation sleeve is shown in the figure. In the figure, 1 is a frame support, 2 is a spring plate, 3 is a bottom support, 4 is a heat pipe hoop fastener, 5 is a heat pipe, 6 is a hoop support plug, 7 is a heat insulation part, 8 is an insulation sleeve, 9 is an insulation sleeve group, 11 is a support top seat, 12 is a support bottom seat, 13 is a transition metal pipe, 14 is a bolt hole, 15 is an insulation pad, 16 is an insulation gasket, and 17 is an insulation bolt sleeve. DETAILED DESCRIPTION

[0020] The present application will be described below in conjunction with the drawings in the present application.

[0021] As Figure 2As shown, the vacuum collector tubes arranged inside the main body of the solar collector focus sunlight to provide a basic heat exchange structure for molten salt heating. The directions of the molten salt inlet and outlet are marked. Molten salt flows into the solar collector from the inlet, is heated and flows out from the outlet, realizing the conversion and transfer of light energy to heat energy. F1 and F2 are flow sensors, T1 and T2 are temperature sensors, and P1 and P2 are pressure sensors; Solar energy is collected by a parabolic trough collector to heat molten salt. Sensors monitor the state parameters of the molten salt in real time, and the operation of the collector is regulated by a control system to ensure that the molten salt circulates at appropriate temperature, flow rate and pressure, providing a stable high-temperature heat source for subsequent power generation or heating processes.

[0022] The solar collector's main body features a rationally arranged array of vacuum collector tubes. By focusing sunlight, it establishes a basic heat exchange structure for molten salt heating, efficiently converting abundant solar energy into thermal energy. The molten salt absorbs this heat, providing a high-temperature heat source for subsequent power generation or heating, thus improving the utilization efficiency of solar energy. The inclusion of flow, temperature, and pressure sensors enables real-time and accurate monitoring of key parameters such as molten salt flow rate, temperature, and pressure. This helps to promptly understand the molten salt's operating status within the collector, providing data support for stable system operation. The control system adjusts the collector's operation based on real-time data from the sensors, ensuring the molten salt circulates at suitable temperature, flow rate, and pressure. This effectively prevents system failures caused by abnormal parameters, ensuring long-term stable operation of the collector and reducing equipment damage risks and maintenance costs. Through this process of photothermal conversion, monitoring, and control, a stable high-temperature heat source is provided for subsequent power generation or heating, guaranteeing the reliability and stability of the solar thermal power generation or heating system and improving the overall quality of energy supply.

[0023] like Figure 3 As shown, the molten salt trough solar collector system includes four collector units. Molten salt enters the collector from a low-temperature pipe, is heated by the vacuum collector tube to become high-temperature molten salt, and flows out from the high-temperature pipe, realizing the conversion and transfer of light energy to heat energy. The collector R is made of stainless steel metal tube. A terminal is led out from the drive bracket in the middle of the collector group and connected to the positive terminal of the DC power supply G. Terminals are led out at both ends of the collector group's heat collection circuit and connected to the negative terminal of the DC power supply, and are simultaneously grounded. By passing DC power to the collector group's heat collection circuit, the heat is generated by the metal's own resistance. At the same time, the main pipeline or other heat collection circuits are shielded by the grounding devices at both ends.

[0024] The low-temperature molten salt enters the system from the left low-temperature molten salt pipeline, starts to circulate in the system under the regulation of the valve FM1, and sequentially flows through the SCA1, SCA2, SCA3 and SCA4 heat collecting units; in each heat collecting unit, the vacuum heat collecting tube focuses the sunlight to convert the solar energy into heat energy, heats the flowing molten salt, and gradually increases the temperature of the molten salt; after continuous heating of the molten salt by the multiple heat collecting units, the molten salt becomes high-temperature molten salt, and finally flows out of the system from the right high-temperature molten salt pipeline to provide a high-temperature heat source for the subsequent power generation or heat supply process; the molten salt tank type heat collector system monitors the state parameters of the molten salt in real time through sensors, and the control element adjusts the valve opening degree and the heat collecting tube angle according to the parameters to ensure that the molten salt circulates in the best state and improves the light-heat conversion efficiency.

[0025] Among them, T1, T2 are temperature sensors at the beginning and end of the heat collector group circuit, F1, F2 are flow sensors at the beginning and end of the heat collector group circuit, P1, P2 are pressure sensors at the beginning and end of the heat collector group circuit, and each group of sensors comprehensively discriminates the preheating and thawing control for the control circuit. The FM1 and FM6 valves are used to isolate the heat collector from the main pipeline. FM2, FM3, FM4 and FM5 are used for corresponding heat collector group accident salt discharge.

[0026] The system is provided with four heat collecting units, and the low-temperature molten salt sequentially flows through each unit. The vacuum heat collecting tube in the unit can effectively focus the sunlight to efficiently convert solar energy into heat energy, continuously heat the molten salt, and finally output high-temperature molten salt to provide sufficient and stable high-temperature heat source for subsequent power generation or heat supply, greatly improving the utilization efficiency of solar energy; the flow, temperature, pressure and other state parameters of the molten salt are monitored in real time by means of sensors, so that the running condition of the molten salt in the system can be grasped in time and accurately, and reliable data support is provided for the stable operation and accurate control of the system; the control element adjusts the valve opening degree and the heat collecting tube angle in time according to the parameters fed back by the sensor; the molten salt circulates under the best temperature, flow and pressure conditions, effectively avoids system failure caused by abnormal parameters, and ensures long-term stable operation of the system; through the synergistic effect of the three links of light-heat conversion, state monitoring and intelligent control, the system can maintain an efficient and stable operating state under different working conditions, improve the light-heat conversion efficiency, and reduce the operation and maintenance cost.

[0027] As shown in Figure 1 The molten salt tank type heat collector preheating control method of the present application specifically comprises the following steps: S1, before starting the heat collecting system, based on the molten salt injection characteristics, determine the initial preheating execution parameters of each heat collector, and control the corresponding heating components to initially heat the heat collector according to the initial preheating execution parameters; S2, during the injection process, real-time monitor the state difference vectors of each heat collector; the state difference vector represents the difference between the state parameters at the input end and the output end of the heat collector; S3, inputting the state difference vector into a preset preheating adjustment model in response to the difference of any state parameter exceeding a corresponding preset fluctuation range, to obtain a preheating adjustment factor; S4, correcting the initial preheating execution parameter based on the preheating adjustment factor to obtain a real-time preheating execution parameter, and using the real-time preheating execution parameter to control the corresponding heating component to perform real-time heating on the heat collector.

[0028] In the embodiment, before the heat collection system is started, the initial preheating execution parameter of each heat collector is determined based on the molten salt injection feature, and the corresponding heating component is controlled to perform initial heating; the individual differences of the heat collectors are considered, so that the initial preheating is more suitable for the actual situation, which helps to improve the preheating effect and efficiency; During the injection process, the state difference vector of each heat collector is monitored in real time, which includes the temperature difference, pressure difference and flow difference between the input end and the output end of the heat collector; by comprehensively monitoring the difference of these key state parameters, the change of the running state of the heat collector can be grasped in time; When the difference of any state parameter exceeds the corresponding preset fluctuation range, the state difference vector is input into the preset preheating adjustment model, which can timely find abnormal conditions such as the output end temperature of the heat collector meeting the standard but the flow suddenly decreasing due to local blockage, effectively identify the potential frozen blockage risk, and avoid the serious consequences such as local frozen blockage of the pipeline, abnormal increase of pressure and even valve jam caused by the existing control method which is difficult to find such problems in time; The preheating adjustment factor obtained based on the preheating adjustment model is used to correct the initial preheating execution parameter to obtain a real-time preheating execution parameter, and the real-time preheating execution parameter is used to control the corresponding heating component to perform real-time heating on the heat collector; the heating strategy can be dynamically adjusted according to the actual running state of the heat collector, which improves the flexibility and accuracy of the control, ensures that the heat collector can maintain good preheating effect under different working conditions, and guarantees the stable operation of the whole photo-thermal power generation system.

[0029] In some embodiments of the application, for step S1, before the heat collection system is started, the initial preheating execution parameter of each heat collector is determined based on the molten salt injection feature, and the corresponding heating component is controlled to perform initial heating on the heat collector; The molten salt injection feature and the state features of the plurality of heat collectors are obtained; The molten salt injection feature includes the molten salt injection temperature, the molten salt injection pressure and the molten salt freezing point; The molten salt injection temperature reflects the initial thermal state of the molten salt entering the heat collection system; the flow and heat transfer characteristics of molten salt with different temperatures in the heat collector will be different; lower injection temperature means that stronger initial heating is needed to prevent the molten salt from prematurely solidifying in the pipeline, and higher injection temperature reduces the burden of initial heating to a certain extent; The molten salt injection pressure affects the flow speed and distribution of the molten salt in the pipeline; a higher injection pressure can make the molten salt fill the pipeline faster, but at the same time, it will put higher requirements on the sealing and strength of the pipeline; during the preheating process, a suitable injection pressure helps to ensure that the molten salt is uniformly heated, avoiding local overheating or overcooling; The freezing point of the molten salt is the critical temperature at which the molten salt changes from a liquid state to a solid state; in the preheating control, it is necessary to ensure that the temperature in the collector is always higher than the freezing point of the molten salt, so as to prevent the molten salt from freezing and causing the pipeline to be blocked; The collector state features of the plurality of groups correspond to a plurality of collectors in the collector system respectively, and each collector is configured with a set of heating components; the collector state features include the pipeline length, the pipeline inner diameter, and the pipeline initial temperature; The pipeline length means that the longer the pipeline, the longer the time the molten salt stays in the collector, and the more complex the heat transfer process; a longer pipeline requires a longer preheating time and a higher heating power to ensure that the molten salt in the entire pipeline can reach a suitable temperature; The pipeline inner diameter affects the flow cross-sectional area and flow speed of the molten salt; a smaller inner diameter will cause the molten salt to flow faster, but at the same time, it may also increase the flow resistance and affect the heat transfer efficiency; during the preheating process, the heating power needs to be adjusted reasonably according to the pipeline inner diameter to ensure that the molten salt can be uniformly heated; The pipeline initial temperature reflects the thermal state of the collector before starting; if the pipeline initial temperature is low, it means that the collector needs more heat for preheating, and the initial heating power may need to be increased accordingly; on the contrary, if the pipeline initial temperature is high, the initial heating power can be appropriately reduced to save energy.

[0030] Based on the molten salt injection features, the freeze blockage risk of each collector is evaluated by combining the collector state features of each collector respectively, to obtain the freeze blockage risk index corresponding to each collector; The freeze blockage risk evaluation problem is divided into target layer, criterion layer and index layer; the target layer is the freeze blockage risk evaluation; the criterion layer includes two aspects of the molten salt injection features and the collector state features; the index layer is the specific feature parameters; The relative importance weights of each level factor are determined by pairwise comparison; for example, in the criterion layer, the influence degree of the molten salt injection features and the collector state features on the freeze blockage risk is compared, and the corresponding weight is given; in the index layer, each feature parameter is compared pairwise to determine its weight in the corresponding criterion layer; According to the actual values of each feature parameter, it is divided into different evaluation grades, and then the frequency of each feature parameter belonging to each evaluation grade is counted to construct a fuzzy evaluation matrix; The weights and the fuzzy evaluation matrix are combined to obtain the freeze blockage risk index.

[0031] The performance parameters of the heating assembly include at least maximum heating power, heating efficiency, temperature control accuracy, and response time. The maximum heating power represents the maximum heat power that the heating assembly can provide, directly affecting the preheating speed. The heating efficiency represents the efficiency of the heating assembly in converting electrical energy into heat energy, and high efficiency means less energy loss. The temperature control accuracy represents the ability of the heating assembly to accurately control the heating temperature. The response time represents the time from receiving the heating instruction to actually starting heating, and fast response helps to adjust the preheating strategy in time. The preset preheating strategy library includes multiple preheating strategies, each of which is optimized for a specific freeze risk index and heating assembly performance parameter; the strategies in the strategy library include: The staged preheating strategy divides the preheating process into multiple stages according to the freeze risk index, with different heating power and temperature targets set for each stage. The dynamic adjustment preheating strategy dynamically adjusts the heating power and temperature target according to the real-time monitoring of the collector state parameters during the preheating process. The safety redundancy preheating strategy sets higher heating power and temperature margin than normal demand to ensure safe completion of preheating in extreme cases.

[0032] In this embodiment, by accurately evaluating the freeze risk index of each collector, differentiated preheating strategies can be adopted for collectors with different risk levels, effectively avoiding local freezing or overheating caused by uniform preheating parameters, thereby improving the operational safety and reliability of the entire collector system; customizing preheating parameters based on the actual state characteristics and molten salt injection characteristics of the collector ensures that the heating power accurately matches the collector demand, avoiding energy waste; by introducing the performance parameters of the heating assembly, the most suitable preheating strategy can be selected from the preset preheating strategy library, ensuring that the heating assembly operates in the best state, quickly responds to changes in preheating demand, shortens the preheating time, and improves overall preheating efficiency; the preset preheating strategy library contains multiple optimized strategies for different freeze risk indices and heating assembly performance parameters, allowing the system to flexibly adjust the preheating plan according to actual conditions, adapting to preheating demands in different working conditions, and improving the adaptability and flexibility of the system; by accurately controlling the preheating process, equipment damage and maintenance requirements caused by freezing or overheating are reduced, thereby reducing operational and maintenance costs; at the same time, personalized preheating strategies help to extend the service life of equipment, improve the overall economy and reliability of the system.

[0033] In some embodiments of the present application, for step S2, during the injection process, the state difference vector corresponding to each collector is monitored in real time; the state difference vector represents the difference between the state parameters at the input end and the output end of the collector; The state difference vector includes temperature difference, pressure difference, and flow difference. High-precision temperature sensors, flow sensors, and pressure sensors are installed at the input end and the output end of the collector; the temperature, flow, and pressure of the molten salt are accurately measured by the sensors. At the input end of the collector, the temperature sensor captures the temperature of the molten salt entering the collector in real time, the pressure sensor accurately measures the pressure value of the input molten salt, and the flow sensor records the inflow rate of the molten salt; at the output end, the state parameters of the molten salt flowing out of the collector are also monitored by sensors. Taking the temperature parameter as an example, during the molten salt injection process, if the heat transfer inside the collector is normal, there is no local blockage or abnormal heat exchange, the temperature at the input end and the output end should show a reasonable change trend, and the difference between the two should be within a stable range; once there is local blockage, heat transfer is blocked, which may cause the output end temperature to abnormally decrease, and the temperature difference with the input end exceeds the preset fluctuation range; the same is true for the pressure parameter; under normal circumstances, the pressure difference between the two ends of the collector should be maintained within a certain range to ensure the stable flow of the molten salt; if the output end pressure suddenly rises due to blockage or other reasons, the pressure difference exceeds the preset range, which is a warning signal sent by the system; the flow parameter is also critical; when there is a problem inside the collector, the flow at the output end may suddenly decrease, and the difference with the input end flow increases, deviating from the normal fluctuation range. The data of each sensor is collected at regular intervals, and the difference between the corresponding parameters at the input end and the output end is calculated to obtain the state difference vector.

[0034] In this embodiment, the sensors configured at the input end and the output end of the collector collect temperature, pressure, and flow data in real time and calculate the difference, which can directly reflect the flow and heat transfer state of the molten salt in the collector, and realize early identification of potential frozen blockage risks and abnormal working conditions; in view of the characteristics of the molten salt that is prone to solidification and needs to be continuously monitored, by collecting data at regular intervals and calculating the difference, the state change of the molten salt during the flow process can be dynamically tracked, which makes up for the limitations of the prior art which only relies on fixed temperature determination; the state difference vector provides direct input parameters for the subsequent steps; when any difference exceeds the preset range, the adjustment mechanism can be triggered to ensure that the heating strategy can be dynamically adjusted according to the real-time state, avoiding problems such as frozen blockage and pressure abnormalities caused by local abnormalities not being discovered in time, and ensuring the safety and stability of the collector injection process.

[0035] In some embodiments of the present application, for step S3, in response to the difference of any state parameter exceeding the corresponding preset fluctuation range, the state difference vector is input into a preset preheating adjustment model to obtain a preheating adjustment factor; The setting of the preset fluctuation range is based on: The physical characteristic parameters of the molten salt. The molten salt needs to be continuously heated within a certain temperature range, and needs to avoid freezing caused by temperature dropping below the freezing point. Therefore, the preset fluctuation range of the temperature difference needs to be based on the freezing point of the molten salt to ensure that the temperature in the collector is always higher than the freezing point, while considering the influence of the viscosity and flowability of the molten salt at different temperatures on heat transfer and flow; The structural and operating parameter limits of the collector. According to the design parameters of the pipeline of the collector, including the pipeline length, inner diameter, material, etc. The pipeline length and inner diameter determine the flow resistance and residence time of the molten salt in the collector. The pressure loss of a shorter pipeline is smaller, and the fluctuation range of the pressure difference needs to be adapted to its flow characteristics. The normal range of the pressure difference of a longer pipeline needs to be widened to adapt to the natural resistance difference. The design pressure capacity of the collector limits the upper limit of the fluctuation of the pressure difference to avoid leakage or damage caused by excessive pressure difference exceeding the strength of the pipeline; Historical operation data and experimental verification results. Based on the historical operation data of similar collectors under different working conditions, the fluctuation intervals of the temperature difference, pressure difference and flow difference during normal operation are statistically analyzed. During the normal salt injection process without freezing and local blockage, the parameter difference range between the input and output is recorded through a large number of experiments, which is used as the basis for the preset fluctuation range; The performance of the heating assembly and the safety redundancy of the system. The maximum heating power, temperature control accuracy and other performance parameters of the heating assembly are considered. The fluctuation range of the temperature difference needs to be appropriately widened for heating assemblies with lower temperature control accuracy to avoid misjudgment caused by equipment errors. At the same time, safety redundancy is reserved, such as setting the upper limit of the pressure difference to be lower than 80% of the burst pressure of the collector to ensure the safety of the system in extreme conditions; The main task of the preheating adjustment model is to determine the corresponding preheating adjustment factor according to the input state difference vector. The preheating adjustment factor is the correction amount of the initial preheating execution parameter, which helps to optimize the heating strategy; Once the state difference vector is input, the adjustment model will generate a preheating adjustment factor based on the previously trained model. The preheating adjustment factor represents the correction degree of the current collector state. When the state difference is large, the adjustment factor will increase to increase the preheating intensity, ensure more uniform and rapid heating, and avoid the risk of freezing caused by too low temperature or local blockage of the collector.

[0036] In this embodiment, by setting a reasonable preset fluctuation range and adjusting the preheating execution parameters in real time according to the state difference vector, the freezing and blocking phenomenon caused by excessively low temperature or local blockage of the heat collector can be effectively avoided; in particular, by considering the freezing point of the molten salt, the pipeline design of the heat collector and the performance of the heating assembly, the temperature in the heat collector can be ensured to be always within a safe range, avoiding problems such as freezing and blocking, pressure abnormalities, valve jamming and the like caused by excessively low temperature or poor flow, thereby greatly improving the safety of the system; the method dynamically adjusts the heating intensity, making the heating process of the heat collector more uniform and efficient; in the case of large state difference, the adjustment factor will increase, enhancing the heating intensity to ensure that the temperature can quickly rise and remain in an appropriate range; not only helps to avoid the risk of local low temperature, but also improves the heat conversion efficiency of the heat collector, shortens the heating time, and thus improves the overall system efficiency; by combining the physical properties of the heat collector, historical operation data and experimental results, the setting of the fluctuation range can more accurately adapt to the needs of different heat collectors and different working conditions, reducing the misjudgment or response lag caused by fixed temperature threshold or unified control strategy in traditional control methods, effectively avoiding the risk of insufficient heating or excessive heating caused by system errors; considering the maximum heating power, temperature control accuracy and other performance parameters of the heating assembly, and combining the safety redundancy design, the system can maintain high safety in extreme cases; in the case of abnormal fluctuations, the system can respond in time to ensure that the heat collector will not be damaged or broken due to excessive heating or excessive pressure during operation, effectively prolonging the service life of the equipment and reducing the failure rate; this step dynamically adjusts the control system by real-time monitoring of the state difference of the heat collector and according to the preset fluctuation range, making the control system have strong intelligence and self-adaptability; not only can it respond to the state change of the heat collector in real time, but also can continuously optimize according to the historical data and experimental verification results, improving the adaptability of the heat collector and ensuring stable operation under different working conditions; by avoiding local freezing and blocking, pipeline blockage and other problems, the failure frequency and maintenance cost of the equipment are reduced; at the same time, more accurate heating control can improve the heat collection efficiency and reduce energy consumption, thereby optimizing the economic benefits of the entire system, helping to reduce the maintenance and operation cost of the heat collector and improve the economy of the overall system; the implementation of this step dynamically adjusts the preheating strategy by combining multiple factors, which can effectively improve the safety, thermal efficiency, intelligence and system stability of the heat collector, while enhancing the redundancy design to ensure stable and efficient operation of the system under various working conditions; the beneficial effects of this step not only lie in improving the safety and stability of the system, but also help to improve the economic benefits of the system and reduce the failure rate and maintenance cost of the equipment.

[0037] In some embodiments of the present application, for step S4, the initial preheating execution parameters are corrected based on the preheating adjustment factor to obtain real-time preheating execution parameters, and the corresponding heating components are controlled to heat the collector in real time according to the real-time preheating execution parameters; The initial preheating execution parameters are determined, and the initial preheating execution parameters include heating power, heating voltage, target temperature, and heating time length; The initial preheating execution parameters are first subjected to boundary check to ensure that they are within the safe operation range of the collector heating system, so as to avoid equipment damage caused by out-of-standard parameters; For the heating power and the heating voltage, the initial values are directly multiplied by the preheating adjustment factor to obtain real-time heating power and voltage, so as to adjust the current passing through the stainless steel metal pipe of the collector and change the heating intensity; for the target temperature, the correction needs to ensure that it is always not lower than the freezing point of the molten salt to prevent the molten salt from freezing in the pipeline, and the target temperature is fine-tuned in combination with the heat loss of the collector; for the heating time length, it is adjusted according to the size of the adjustment factor, if the abnormal situation is more serious, the adjustment factor is larger, the heating time length can be appropriately prolonged to ensure enough time to resolve the potential frozen risk, if the heating is excessive, the adjustment factor is smaller, and the time length is shortened to avoid energy waste; The control cabinet of the corrected real-time preheating execution parameters controls the corresponding heating components to heat the collector in real time, and the state parameters of the input end and the output end of the collector are monitored to ensure that the heating effect meets the expectation and guarantees the safe and stable operation of the collector.

[0038] In this embodiment, boundary check is performed on the initial preheating execution parameters to ensure that the heating power, heating voltage, target temperature and heating duration are always within the safe operation range of the heat collector, avoiding equipment damage or unstable operation due to excessive parameters; the heating intensity is dynamically adjusted through the real-time adjustment of the corrected heating power and heating voltage, adapting to the actual needs of the heat collector under different operating conditions, ensuring that the system is always in the optimal working state, and avoiding energy waste caused by insufficient or excessive heating; the correction of the target temperature can ensure that the temperature is always above the freezing point of the molten salt, avoiding the freezing of the molten salt in the pipeline, thereby avoiding pipeline blockage or freezing and reducing the risk of potential frozen blockage; the heating duration is dynamically adjusted through the adjustment factor, which can be appropriately extended or shortened according to the actual working condition of the heat collector; if an abnormal situation occurs, the heating duration will be appropriately extended to ensure that the molten salt is completely thawed and flows smoothly; on the contrary, if there is no abnormal situation, the heating duration can be appropriately shortened to avoid energy waste; through real-time monitoring and adjustment of the state parameters of the input and output ends of the heat collector, the control system can effectively feedback and adjust to ensure that the heating process meets the expectations, improve the heating effect and safety and stability of the heat collector, and prolong the service life of the equipment; by accurately adjusting each parameter, the problems of overheating or overcooling, uneven heating, etc. are avoided, effectively reducing the risk of failure or damage caused by equipment overload, freezing, blockage, etc.; this step can adjust the preheating execution parameters in real time to ensure the safety of the equipment while improving the operating efficiency and stability of the heat collector, preventing frozen blockage, optimizing energy consumption, and ensuring long-term reliable operation of the heat collector.

[0039] The application also provides a molten salt tank-type heat collector preheating control device, which specifically comprises the following modules: A support mechanism for insulating and supporting the heat collector metal pipe; An initial preheating execution module for determining the initial preheating execution parameters of each heat collector based on the molten salt injection characteristics before the start of the heat collection system, and controlling the corresponding heating components to initially heat the heat collector according to the initial preheating execution parameters; A state difference monitoring module for collecting and calculating the state difference vector between the input end and the output end of each heat collector in real time during the molten salt injection process, wherein the state difference vector at least includes temperature difference, pressure difference and flow difference; A preheating adjustment calculation module for inputting the state difference vector into the preheating adjustment model and outputting a preheating adjustment factor when the difference of any state parameter exceeds the corresponding preset fluctuation range; A real-time preheating execution module for correcting the initial preheating execution parameters according to the preheating adjustment factor, generating real-time preheating execution parameters, and controlling the corresponding heating components to heat the heat collector in real time according to the real-time preheating execution parameters.

[0040] In the embodiment, the device customizes initial preheating execution parameters for each heat collector according to the molten salt injection features and structural differences of each heat collector through the initial preheating execution module, so that the heat collector can be in the most suitable heating state for its own conditions in the initial preheating stage, avoiding the situation of insufficient or excessive preheating of some heat collectors caused by the use of fixed parameters, thereby improving the preheating efficiency; the real-time preheating execution module can correct the initial preheating execution parameters according to the preheating adjustment factor and control the heating assembly to heat the heat collector in real time; during the molten salt injection process, the device can timely adjust the heating power and mode as the internal state of the heat collector changes, so as to always keep the heat collector in the best preheating state; the problem of uneven or insufficient preheating caused by excessive or insufficient heating power in the later preheating stage is avoided, further improving the preheating efficiency; the state difference monitoring module collects and calculates the state difference vector of the input end and the output end of the heat collector in real time during the molten salt injection process, and the state difference vector includes temperature difference, pressure difference and flow difference; when abnormal conditions such as local blockage leading to flow reduction occur, the module can quickly detect the change of flow difference; and the preheating adjustment calculation module inputs the state difference vector into the preheating adjustment model to output the preheating adjustment factor, and then adjusts the heating strategy through the real-time preheating execution module.

[0041] Further, the support mechanism is various types of support structures for fixing and supporting the heat collector metal pipe, including but not limited to driving supports, hoop supports, and other support forms suitable for molten salt tank heat collectors, such as truss supports, cantilever supports, floor supports, etc.; the core function is to bear the weight of the heat collector metal pipe and maintain its spatial position, ensuring the relative fixation of the heat collector metal pipe and the external structure.

[0042] In order to block the conductive path between the heat collector metal pipe and the support mechanism, ensure that the direct current heating circuit only generates heat through the resistance of the heat collector pipe 5 itself, and avoid the risk of electric leakage and short circuit; an insulation structure is provided between all support mechanisms and the heat collector metal pipe.

[0043] The insulation structure is provided at the contact or connection position between the heat collector metal pipe and the support mechanism, such as the metal contact surface, the threaded position of the connecting bolt, the fixing position of the support and the heat collector, etc.; the structure form of the insulation component includes but is not limited to a pad, a bolt sleeve, a gasket, a sleeve, an embedded block, a coating, a set, etc., and the material is a high-temperature-resistant insulating material.

[0044] Specifically, as Figure 4As shown, taking the driving support as an example, the driving support is composed of a support top base 11, a support bottom base 12, a transition metal pipe 13 and a connecting bolt passing through a bolt hole 14; a first insulation assembly is arranged on the driving support, and the first insulation assembly realizes insulation between a metal surface of the driving support and the heat collecting pipe 5 through an insulation pad plate 15, an insulation bolt sleeve 17 and an insulation gasket 16; Specifically, the insulation pad plate 15 can be made of aluminum oxide, zirconium oxide or silicon nitride ceramic, has an area consistent with the size of the lower surface of the support top base 11 and the upper surface of the support bottom base 12, is installed between the metal contact surfaces of the two, and blocks direct conduction; the insulation bolt sleeve 17 is a ceramic tubular structure, has an inner diameter matched with the diameter of the screw rod of the connecting bolt, is sleeved outside the screw rod, has a length covering the exposed section of the screw rod, and avoids contact between the screw rod and the metal hole wall of the support; the insulation gasket 16 is a ceramic disc, has an outer diameter slightly larger than the diameter of the nut, is arranged between the nut and the outer surface of the support top base 11, and enhances the insulation effect at the nut; the connecting bolt passes through the support top base 11, the insulation bolt sleeve 17, the insulation pad plate 15, the support bottom base 12, the insulation gasket 16 and the nut in sequence, forms full-path insulation blocking, and ensures that the driving support and the heat collecting pipe 5 are not in metal conduction.

[0045] More specifically, for the bolt hole 14 of the support bottom base 12, an annular installation groove is arranged on the inner wall of the bolt hole 14, has a groove depth ≥1 / 2 of the depth of the bolt hole 14, and has a groove width matched with the thickness of the insulation material; the insulation material is made of PEEK or other high-temperature-resistant insulation material; the insulation material is processed into an annular embedded block, is tightly embedded in the installation groove, and makes the bolt only contact with the insulation material when passing through, thereby completely blocking the conduction path between the screw rod and the support bottom base 12; the embedded structure avoids displacement of the insulation part during tightening of the bolt, and improves the insulation reliability during long-term use.

[0046] Further, as shown, Figure 5 taking the hoop support as an example, the hoop support is composed of a frame support 1, a spring plate 2, a hoop support plug-in pin 6, a hoop fastener 4 and a bottom support 3, and is used for fixing the heat collecting pipe 5; a second insulation assembly realizes insulation between the hoop and the heat collecting pipe 5 through an insulation sleeve 8, a coating, a heat insulation part 7 and an insulation sleeve group 9 and the like; Specifically, the insulation sleeve 8 is a T-shaped ceramic structure, and the specific structure is shown in Figure 6 The material is aluminum oxide, can resist a temperature ≥300℃, and the horizontal section is sleeved outside the hoop support plug-in pin 6; the inner diameter of the sleeve is matched with the diameter of the plug-in pin, the wall thickness is ≥3mm, the sleeve is fixed through the hoop fastener 4, and the metal contact between the plug-in pin and the frame support 1 is blocked; The heat insulation part 7 is made of high-temperature-resistant aerogel, has an inner diameter consistent with the outer diameter of the heat collecting pipe 5, and has a width equal to the distance between two adjacent heat collecting pipes 5; the heat insulation part 7 is fixed on the frame support 1 through the hoop fastener 4 of the heat collecting pipe 5, thereby realizing heat insulation and insulation between the hoop fastener 4 and the heat collecting pipe 5; The insulating sleeve set 9 is composed of multiple layers of high-temperature-resistant insulating materials, including mica, bakelite, etc., and has a sleeve structure that is suitable for the installation size of the spring plate 2, and is provided with through holes corresponding to the mounting hole positions of the spring plate 2 and used for penetrating the connecting components; the insulating sleeve set 9 is installed at the spring plate 2 of the hoop support, tightly adheres to the surface of the spring plate 2 on the inside, and forms an insulating interval with other metal components of the hoop support on the outside; by arranging the insulating sleeve set 9 at the mounting position of the spring plate 2, the conductive path between the spring plate 2 and the metal structure of the hoop support is blocked, and the insulation between the hoop support and the metal pipe of the heat collector is further strengthened, and in cooperation with the heat insulation piece 7 and the insulating sleeve 8, reliable insulation between the hoop support and the metal pipe of the heat collector is achieved.

[0047] In the present embodiment, by arranging the insulating components at the bolt fastening position of the driving support and the clamping position of the hoop support, the conductive path between the metal pipe of the heat collector and the support mechanism can be effectively blocked, the direct current heating circuit is ensured to only generate heat through the resistance of the heat collector itself, the risk of electric leakage and short circuit caused by metal contact is avoided, the accurate transmission of the heating current is ensured, and the preheating efficiency and the safety of the system are improved.

[0048] For the above-mentioned embodiments, it should be noted that the materials of the first and second insulating components are not limited to the specific listed insulating materials such as mica, bakelite, ceramic (alumina, zirconia, silicon nitride), PPS (polyphenylene sulfide), PEEK (polyether ether ketone), polyimide, etc., but also include all similar or equivalent insulating materials that can meet the requirements of high-temperature resistance and high insulation performance, and the core is to ensure reliable insulation between the metal pipe of the heat collector and the support mechanism under high-temperature working conditions, and to block the conductive path to ensure the safety and effectiveness of the direct current heating circuit.

[0049] The basic principles, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A preheating control method for a molten salt trough solar collector, characterized in that, include: Before the solar collector system is started, the initial preheating execution parameters of each solar collector are determined based on the molten salt injection characteristics, and the corresponding heating components are used to control the initial heating of the solar collector. During the injection process, the state difference vector corresponding to each collector is monitored in real time; the state difference vector represents the difference of various state parameters between the input and output ends of the collector. In response to any state parameter difference exceeding the corresponding preset fluctuation range, the state difference vector is input into the preset preheating adjustment model to obtain the preheating adjustment factor. The initial preheating execution parameters are corrected based on the preheating adjustment factor to obtain real-time preheating execution parameters, and the corresponding heating components are used to control the real-time heating of the solar collector.

2. The preheating control method for a molten salt trough solar collector according to claim 1, characterized in that, Before starting the solar collector system, based on the molten salt injection characteristics, the initial preheating execution parameters for each collector are determined, including: Acquire molten salt injection characteristics and multiple sets of collector status characteristics; the multiple sets of collector status characteristics correspond to multiple collectors in the solar collector system, wherein each collector is equipped with a set of heating components; Based on the molten salt injection characteristics, and combined with the collector status characteristics of each collector, the freezing and blockage risk assessment of each collector is carried out to obtain the freezing and blockage risk index corresponding to each collector. For each solar collector, the initial preheating execution parameters corresponding to that heating component are obtained by mapping the corresponding freezing and blockage risk index and the performance parameters of its heating component in a preset preheating strategy library.

3. The preheating control method for a molten salt trough solar collector according to claim 2, characterized in that, The molten salt injection characteristics include molten salt injection temperature, molten salt injection pressure, and molten salt freezing point.

4. The preheating control method for a molten salt trough solar collector according to claim 2, characterized in that, The characteristics of the solar collector include pipe length, pipe inner diameter, and initial pipe temperature.

5. The preheating control method for a molten salt trough solar collector according to claim 2, characterized in that, The performance parameters of the heating component include at least the maximum heating power, heating efficiency, temperature control accuracy, and response time.

6. The preheating control method for a molten salt trough solar collector according to claim 2, characterized in that, The preset preheating strategy library includes strategies such as phased preheating strategy, dynamic adjustment preheating strategy, and safety redundancy preheating strategy.

7. A preheating control device for a molten salt trough solar collector, characterized in that, include: Support mechanism, used to provide insulating support for the metal tubes of the solar collector; The initial preheating execution module is used to determine the initial preheating execution parameters of each collector based on the molten salt injection characteristics before the solar collector system is started, and to control the corresponding heating components to perform initial heating on the collector. The state difference monitoring module is used to collect and calculate the state difference vector between the input and output ends of each collector in real time during the molten salt injection process. The state difference vector includes at least temperature difference, pressure difference and flow rate difference. The preheating adjustment calculation module is used to input the state difference vector into the preheating adjustment model and output the preheating adjustment factor when the difference of any state parameter exceeds its corresponding preset fluctuation range. The real-time preheating execution module is used to correct the initial preheating execution parameters according to the preheating adjustment factor, generate real-time preheating execution parameters, and control the corresponding heating components to heat the collector in real time.

8. The preheating control device for a molten salt trough solar collector according to claim 7, characterized in that, The support mechanism includes at least a drive bracket and a clamp bracket; The drive bracket is provided with a first insulating component to achieve insulation between the drive bracket and the metal tube of the solar collector. The clamp bracket is provided with a second insulation component to achieve insulation between the clamp bracket and the metal tube of the solar collector. Both the first insulating component and the second insulating component are made of insulating material.

9. The preheating control device for a molten salt trough solar collector according to claim 8, characterized in that, The first insulating component includes at least an insulating pad, an insulating bolt sleeve, and an insulating gasket; The insulating pad is installed between the top seat of the drive bracket and the base of the bracket; The insulating bolt sleeve is adapted to the screw of the drive bracket and is sleeved on the outside of the screw; The insulating gasket is placed on the nut side of the drive bracket.

10. The preheating control device for a molten salt trough solar collector according to claim 8, characterized in that, The second insulation assembly includes at least a thermal insulation component, an insulating sleeve, and an insulating sleeve group; The inner diameter of the heat insulation component is the same as the outer diameter of the collector metal tube, the width is the distance between two adjacent collector metal tubes, and it is fixed to the collector metal tube by a clamp structure. The insulating sleeve is fitted onto the outside of the pin of the clamp bracket; The insulating sleeve is installed at the spring plate of the clamp bracket.

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