A tower type optical thermal mirror field energy flow stability control method based on a physical connection topology

Abstract

The application discloses a tower type optical thermal mirror field energy flow stable control method based on a physical connection topology and belongs to the field of solar thermal power generation. Physical connection attributes of a control row, a communication branch, a power supply branch and the like of a heliostat are acquired, a physical connection topology is established, and a physical control domain is constructed; a target point heat absorber partition energy flow contribution matrix of the heliostat is calculated; in a normal operation stage, a physical control domain dispersion constraint is introduced to limit the energy flow contribution proportion of a single physical control domain to any heat absorber heated partition; when the physical control domain fails, a partition energy flow gap is calculated according to a target point allocation state before the failure, a compensation mirror group is screened from a physically independent non-fault control domain; and compensation control is performed. The application can reduce the risk of a local energy flow sudden drop of the heat absorber caused by the physical connection failure, improve the response speed of the fault compensation and the reliability of the compensation mirror group, guarantee the thermal safety of the heat absorber, and be suitable for large-scale tower type optical thermal mirror fields.

Description

Technical Field

[0001] This invention relates to the field of control technology for tower solar thermal power generation mirror fields, and particularly to a method for stable control of energy flow in tower solar thermal mirror fields based on physical connection topology. Background Technology

[0002] Tower-type solar thermal power generation systems typically include a heliostat field, an absorber tower, absorbers, a heat storage and exchange system, and power generation units. The heliostat field consists of thousands to tens of thousands of heliostats. A control system drives these heliostats to track the sun, reflecting solar radiation onto the absorber's heating surface. This heats the working fluid, generating high-temperature steam for power generation. To achieve a reasonable distribution of energy flux density on the absorber surface, the heliostat control system usually divides the absorber's light-receiving surface into multiple target points or heating zones, assigning a target point to each heliostat. This allows the reflected light spots from each heliostat to superimpose on the absorber, forming the desired energy flux distribution.

[0003] Existing methods for target point allocation and energy flow control in the heliostat field mainly revolve around the following aspects: First, prioritizing the allocation of heliostats to target points with higher reflection efficiency to maximize optical efficiency; second, aiming for uniform energy flow on the receiver surface by optimizing allocation to suppress local energy flow peaks; third, considering the cost of target point switching to minimize frequent adjustments to the heliostat target points; and fourth, combining receiver temperature monitoring to deflect some heliostats to safe target points when local overheating occurs. Furthermore, in the event of cloud shadow disturbances, changes in normal direct irradiance, or changes in grid power demand, existing methods typically employ full-field re-optimization or local adjustment strategies to maintain the stability of the receiver energy flow distribution.

[0004] However, the above methods still have the following shortcomings in practical engineering applications: First, existing target point allocation methods do not fully consider the correlation of physical connection failures between heliostats. Heliostat fields typically employ a hierarchical and zoned control structure, with multiple heliostats potentially sharing the same control row, the same zone control unit, the same communication branch, the same power supply branch, or the same control cabinet. When a failure occurs in any of these physical connection links, all heliostats associated with that link may simultaneously lose their ability to track the sun or adjust their target points. Existing target point optimization methods allocate targets based solely on the spatial location, optical efficiency, or energy flow contribution of the heliostats, without establishing a fault correlation model based on the physical connection topology. This results in the target point allocation scheme lacking energy flow stabilization capabilities when physical connection failures occur.

[0005] Second, heliostats within the same physical control domain may be concentrated in the same heated zone of the receiver. Because existing methods do not limit the contribution percentage of the same control line or communication branch to a local heated zone during the allocation process, it often occurs that heliostats in a certain physical control domain are concentrated on a single panel or zone of the receiver. If this physical control domain fails due to communication interruption, power supply anomaly, or zone control unit malfunction, the energy flow to that heated zone will drop sharply, causing a drastic change in the local heat load of the receiver, and may even trigger tube panel thermal fatigue or over-temperature protection shutdown.

[0006] Third, the response speed of the full-field re-optimization method after a fault is slow and the disturbance is large. When a fault occurs in a certain control line or physical control domain, if global target point re-optimization is performed on all available heliostats, it is necessary to recalculate the energy flow contribution and optimal allocation scheme of a large number of heliostats, which is time-consuming and difficult to meet the requirements of real-time control. At the same time, re-optimization may cause the target points of a large number of heliostats to change simultaneously, further aggravating the fluctuation of the receiver's energy flow distribution and increasing the risk of thermal runaway.

[0007] Fourth, existing methods lack preventative mitigation mechanisms before failures occur. Most mirror field control strategies only take remedial measures after overheating, abnormal energy flow, or failures have occurred, failing to proactively limit the upper limit of energy flow contribution from a single physical control domain to any receiver zone during normal operation. This passive approach makes the size and distribution of energy flow gaps after a failure uncontrollable, increasing the difficulty of subsequent compensation.

[0008] Fifth, existing methods do not consider physical independence when selecting fault-compensating heliostats. After a control row or physical control domain fails, a common strategy is to select mirrors with high optical contribution similarity from the remaining heliostats for compensation. However, these selected heliostats may belong to the same communication branch, power supply branch, or area control unit as the fault control domain, posing a risk of secondary failures. If the physical connection of this compensation mirror group experiences another anomaly, it will lead to continuous failures, seriously threatening the thermal safety of the receiver.

[0009] In summary, there is an urgent need to propose a control method that can organically combine physical connection topology with target point allocation, energy flow contribution calculation, fault domain identification, compensation mirror group selection, and staged energy flow recovery, so as to improve the energy flow stability of tower photothermal mirror fields under physical connection faults. Summary of the Invention

[0010] To address the aforementioned technical problems, this invention provides a method for stabilizing energy flow in a tower-type photothermal mirror field based on physical connection topology, aiming to reduce the risk of sudden drops in local energy flow in the receiver caused by physical connection failures and improve the operational reliability and thermal safety of the mirror field.

[0011] To achieve the above objectives, the technical solution of the present invention is as follows: A method for stabilizing energy flow in a tower-type photothermal mirror field based on physically connected topology includes the following steps: Step S1: Obtain the physical connection properties of the heliostats in the tower-type photothermal mirror field, establish the physical connection topology between the heliostats based on the physical connection properties, and construct one or more physical control domains for heliostats that have common fault correlations. Step S2: Establish the set of receiver heating zones and the set of target points, and calculate the energy flow contribution of each heliostat to each receiver heating zone at different target points, forming the heliostat-target point-receiver zone energy flow contribution matrix; Step S3: During the normal operation of the mirror field, the target point allocation scheme is checked or locally adjusted based on the target energy flow distribution of the receiver and the dispersed constraints of the physical control domain; Step S4: When a failure to track the sun is detected in a certain physical control domain, the energy flow contribution originally undertaken by the faulty physical control domain to each receiver heating zone is calculated based on the target point allocation state of each heliostat in the faulty physical control domain before the failure and the energy flow contribution matrix, and is used as the zone energy flow gap. Step S5: Select candidate compensating heliostats from the non-faulty physical control domains. The candidate compensating heliostats must simultaneously meet the following requirements: they have no common fault correlation with the faulty physical control domain, they have an effective energy flow contribution to the receiver heating zone corresponding to the partitioned energy flow gap, and the adjustment does not cause the receiver thermal safety constraint to exceed the limit. Step S6: Determine the compensation mirror group and its compensation target point based on the energy flow contribution, target point adjustment, physical connection correlation and receiver thermal safety margin of the candidate compensation heliostats; Step S7: According to the energy flow ramping constraint and the phased compensation constraint, send the compensation target point phased adjustment command to the compensation mirror group so that the energy flow distribution of each heated zone of the receiver is restored to the allowable deviation range.

[0012] In the above scheme, the physical connection attributes include at least one of the following: control line number, area control unit number, communication branch number, and power supply branch number; the common fault correlation is determined by at least one of the following situations: the same control line, the same area control unit, the same communication branch, the same power supply branch, the same control cabinet, or the same network switching node.

[0013] In the above scheme, the physical control domain dispersion constraint refers to limiting the energy flow contribution of the same physical control domain to any receiver heating zone to not exceed a preset threshold, expressed as: ,in, For the first The physical control domain for the first The proportion of energy flow contribution of each heat absorber's heated zone This represents the maximum allowed contribution percentage, i.e., the preset threshold. ; in, For decision variables: ; For heliostats Aim at the target point Heat absorption zone of the heat absorber Energy flow contribution, To prevent extremely small positive numbers with a denominator of zero, M is the total number of target points, and N is the total number of heliostats. For the first One physical control domain.

[0014] In the above scheme, the energy flow contribution matrix is ​​as follows: ; in, Normal direct irradiance, The effective reflective area of ​​the heliostat; For heliostats Aim at the target point Overall optical efficiency at that time; The heliostat's light spot falls into the heat-receiving zone of the receiver. The energy flow distribution coefficient.

[0015] In the above scheme, step S3, the target point for verification or partial adjustment during normal operation is represented as: ; in, Heat absorption zone for heat absorber The target energy flow; This represents the total attitude adjustment amount for switching the target point of the heliostat. Heat absorption zone for heat absorber thermal risk indicators Heat absorption zone for heat absorber The actual energy flow, For the first Each physical control domain controls the heat receiving zone of the receiver. The proportion of energy flow contribution, The maximum allowable contribution percentage, i.e., the preset threshold. , , , These are the weighting coefficients.

[0016] In the above scheme, the calculation method for the zoned energy flow gap is as follows: Heat receiver heating zone The fault energy flow gap is: ; in, Before the malfunction occurred, the heliostat Target point allocation status; For heliostats Aim at the target point Heat absorption zone of the heat absorber Energy flow contribution; If some heliostats are not completely inoperable, but still have some usability Then the heat absorber is heated in a specific zone. The fault energy flow gap is: ; in, Indicates heliostat Fully usable This indicates that the device is completely unavailable. This indicates that some parts are available.

[0017] In the above scheme, the determination of the candidate compensation heliostat is achieved through the following optimization objectives: ; in, For the fault energy flow gap, To compensate for energy flow, This is the heliostat attitude adjustment amount. The thermal risk index after compensation. For the physical connectivity matrix, Indicates heliostat Whether it was selected as a compensating lens and: ; To compensate for the allocation variables: ; , which represents the weighting coefficient; the last term is used to suppress the concentration of compensation mirror clusters in the same physical control domain.

[0018] In the above scheme, the compensating mirror group divides the receiver into zones. The compensation energy flow is: ; in, For the candidate compensation heliostat set, For heliostats Aim at the target point Heat absorption zone of the heat absorber Energy flow contribution.

[0019] In the above scheme, the phased adjustment command for the compensation target point is generated using a fifth-order polynomial trajectory or energy flow ramp control, ensuring that the energy flow change rate of each zone of the receiver does not exceed the preset maximum energy flow change rate. ; in, for Current heat absorber partition The actual energy flow, for Current heat absorber partition The actual energy flow, Zone the heat absorber Maximum permissible rate of change of energy flow.

[0020] In the above scheme, after the faulty physical control domain returns to normal, it is first marked as a recovery observation state. After it meets at least one of the recovery conditions of tracking error, communication quality, and drive response time, the compensation contribution of the compensation mirror group is gradually reduced, and the heliostats in the recovered control domain are gradually reintegrated into the target point allocation. The recovery process also satisfies the energy flow ramp-up constraint and the phased compensation constraint.

[0021] Through the above technical solution, the present invention provides a method for stabilizing energy flow in a tower-type photothermal mirror field based on physical connection topology, which has the following beneficial effects: 1. Reduced the risk of sudden drops in localized energy flow in the receiver due to physical connection failures. This invention introduces physical control domain dispersion constraints during the normal operation of the mirror field, actively limiting the energy flow contribution ratio of the same control line, the same communication branch, or the same power supply branch to any heated zone of the receiver. Even if a physical control domain subsequently fails, the resulting energy flow gap has been pre-distributed to multiple zones or multiple control domains, avoiding sudden drops in local energy flow and significantly improving the thermal safety of the receiver.

[0022] 2. Improved the speed of compensation response after a fault. This invention pre-establishes a physical connection topology model and an energy flow contribution matrix for the receiver partition at the heliostat target point. When a fault occurs in the physical control domain, the system does not need to perform time-consuming full-field re-optimization. It can quickly calculate the energy flow gap in each partition based on the target point allocation state and energy flow contribution matrix of the heliostat before the fault, which greatly shortens the fault response time and meets the real-time control requirements.

[0023] 3. Improved the reliability of the compensating lens group This invention introduces a physical independence constraint in the selection of compensation mirror groups, requiring that candidate compensation heliostats and faulty physical control domains do not share common fault correlations (e.g., not belonging to the same control line, the same communication branch, the same power supply branch, etc.). This mechanism effectively avoids compensation mirror groups falling into the same fault risk domain, reduces the probability of secondary faults leading to continuous failures, and enhances the robustness of compensation control.

[0024] 4. Reduced energy flow disturbance during target point switching. This invention balances the heliostat attitude adjustment and the receiver thermal safety margin in the compensation optimization objective, and employs a transitional target point sequence, phased compensation rules, or energy flow ramping constraints to execute the compensation target point adjustment. During the compensation process, the energy flow change rate of each zone of the receiver is always controlled within the allowable range, avoiding drastic energy flow fluctuations caused by target point jumps and ensuring the stability of the mirror field operation.

[0025] 5. Comprehensively improved the thermal safety level of the heat absorber. The target point allocation, fault gap compensation, and recovery control processes of this invention all incorporate receiver thermal safety constraints, including upper limits for local peak energy flow, energy flow gradient, temperature, and temperature rise rate. Simultaneously, real-time corrections are performed during the compensation process using closed-loop feedback (infrared temperature, thermocouples, and energy flow estimation). If any risk of exceeding limits is detected, the compensation scheme is re-optimized, effectively preventing thermal safety issues such as receiver tube overheating, thermal fatigue, and temperature shock.

[0026] 6. Suitable for large-scale tower-type photothermal mirror fields This invention uses the physical control domain as the basic unit for fault correlation modeling, avoiding complex calculations based on a single heliostat. The energy flow contribution matrix can be obtained through offline calculation, table lookup, or digital twin methods, and online optimization requires only a small number of integer or continuous variables. Therefore, this invention can efficiently support large-scale mirror field engineering applications with tens of thousands to hundreds of thousands of heliostats.

[0027] 7. Good compatibility with existing mirror field control systems This invention does not require changes to the hardware structure of the heliostat. It only requires adding software modules such as physical connection topology modeling, energy flow contribution matrix calculation, fault identification, and compensation mirror group selection to the main control server or zone control unit of the heliostat field. It can be directly deployed based on the existing heliostat field database, control line number, communication status, power supply status, and receiver temperature measurement data. The modification cost is low and it is easy to promote.

[0028] In summary, this invention, by introducing physical connection topology into the entire process of target point allocation and fault tolerance control, achieves a leap from "passive response" to "active prevention," significantly improving the energy flow stability, thermal safety, and operational reliability of tower-type photothermal mirror fields under physical connection failures. It has outstanding substantive features and significant progress. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0030] Figure 1 This is a schematic diagram of a method for stabilizing energy flow in a tower-type photothermal mirror field based on physical connection topology, as disclosed in an embodiment of the present invention. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0032] This invention provides a method for stabilizing energy flow in a tower-type photothermal mirror field based on physical connection topology, and specific embodiments are as follows: I. System Configuration and Basic Data This embodiment takes a 50MW tower-type concentrated solar power plant as an example. The heliostat field includes 20,000 heliostats, each with an effective reflective area of ​​20 m². 2 The absorber tower is 150 m high, and the absorber is an external cylindrical shape with a light-receiving surface height of 12 m and a circumference of 360°. The heliostat control system includes: one main control server, eight zone control units, 64 control cabinets, a fiber optic ring communication network, and a zoned DC power supply system. Each heliostat is equipped with an independent controller, communicating with the zone control unit via a fieldbus. An infrared thermal imager is installed on the top of the absorber to monitor the surface temperature distribution in real time.

[0033] II. Specific implementation steps, such as Figure 1 As shown.

[0034] Step S1: Establish the physical connection topology model of the mirror field Obtain the physical connection attributes of each heliostat in the field, including one or more of the following: control line number, area control unit number, communication branch number, power supply branch number, control cabinet number, and switching node number. Establish the physical connection topology between the heliostats based on these attributes. Construct several physical control domains for heliostats with common fault correlations.

[0035] Let the set of field heliostats be: The physical control domain set is as follows: ;in, For the number of heliostats, The number of physical control domains. Indicates the first One physical control domain.

[0036] Definition: If two heliostats share at least one of the following: the same control line, the same zone control unit, the same communication branch, the same power supply branch, or the same control cabinet, then they are considered to have a common fault correlation. A physical connection correlation matrix is ​​established based on this. : ; All heliostats in the field of observation are constructed into several physical control domains. In this embodiment, a total of 202 physical control domains were constructed (including 80 control row level domains, 40 communication branch level domains, 10 power supply branch level domains, 8 zone control unit level domains, and 64 control cabinet level domains).

[0037] Step S2: Establish the target point set and the receiver heating zone. The receiver's light-receiving surface is divided into several heating zones, and a set of target points is set on or near the receiver's light-receiving surface. Target points can be generated based on the receiver panel, tube screen, circumferential angle, height direction, or thermal risk level.

[0038] Let the set of target points be: The heat absorption zone set is as follows: ;in, The number of target points. This represents the number of heating zones in the absorber.

[0039] In this embodiment, the light-receiving surface of the heat absorber is divided into 4 zones along the height direction (bottom layer, lower middle layer, upper middle layer, and top layer) and 8 sectors (one every 45°) along the circumference, forming a total of 32 heating zones. .

[0040] A target point is set at the geometric center of each heated zone, and four defocusing safety target points are set in the safety zones on both sides of the receiver (5 m away from the receiver surface), for a total of 36 target points. .

[0041] Step S3: Calculate the energy flow contribution matrix of the heliostat-target point-supplier zone. For each heliostat Each target point Each heated zone Calculate the energy flow contribution , Indicates heliostat Aim at the target point Heat absorption zone of the heat absorber The energy flow contribution can be obtained through ray tracing, empirical spot models, offline lookup tables, online energy flow inversion, or digital twin models.

[0042] One possible calculation method is: ; in: For the normal direct irradiance, a typical value of 800 W / m is used in this embodiment. 2 (Updated dynamically online); The effective reflective area of ​​the heliostat is 20 m. 2 ; The overall optical efficiency includes specular reflectivity (0.92), atmospheric attenuation efficiency (0.95~0.98), cosine efficiency, and shadow occlusion efficiency. The energy flow distribution coefficient is obtained by integration using the Gaussian spot model and satisfies... If calculated based on power contribution, the unit of this formula is kW; when used for thermal safety verification, it can be divided by the area of ​​the corresponding heated zone to obtain the energy flux density.

[0043] This embodiment uses offline ray tracing software (Soltrace) to pre-calculate all... , forming a size of A three-dimensional energy flow contribution table. It is linearly scaled and corrected at runtime based on real-time DNI and solar position.

[0044] Step S4: During normal operation, target point allocation is performed under topology constraints. Define decision variables: ; For each heliostat that is in a usable state, each usable heliostat satisfies the uniqueness constraint: ; in, This is the set of heliostats that are currently available.

[0045] During normal operation, the heliostat target point allocation scheme is checked or locally adjusted with the goals of satisfying the target energy flow distribution of the receiver, reducing the target point switching amount, controlling local thermal risks and dispersing the contribution of the physical control domain.

[0046] Heat absorber partition The actual energy flow is: ; No. Each physical control domain for partitions The energy flow contribution percentage is: ; in, To prevent extremely small positive numbers with a denominator of zero, in this embodiment, .

[0047] Introducing distributed constraints in the physical control domain: ; in, For the first The physical control domain for the first The maximum allowable contribution percentage for each receiver heating zone. This constraint is used to avoid excessive concentration of contribution from a single physical control domain to a particular receiver zone. This embodiment sets... That is, the energy flow contribution of any physical control domain to any heated zone shall not exceed 40%. The above energy flow contribution can be the power contribution or the energy flow density contribution after conversion by zone area, but the dimensions should be kept consistent in the same calculation process.

[0048] When using an exact solver, the aforementioned dispersed constraints are treated as hard constraints; when using heuristic or iterative optimization methods, they can be relaxed to... The soft penalty term in the solution is used to improve the flexibility of the solution. Both can be selected according to the actual engineering calculation needs.

[0049] The target points for verification or partial adjustment during normal operation are: ; in, Heat absorption zone for heat absorber Target energy flow (bottom layer 200 kW / m) 2 500 kW / m² in the middle and lower layers 2 500 kW / m² in the middle and upper layers 2 Top floor 350 kW / m 2 (circumferentially uniform) This represents the total attitude adjustment amount for switching the target point of the heliostat. Zone the heat absorber Thermal risk indicators: ; in, The upper limit of energy flow for the zone (800 kW / m²) 2 ); , , , In this embodiment, the weighting coefficient is used. .

[0050] This embodiment adopts a two-stage heuristic verification and local adjustment based on the existing target point scheme: first, the contribution ratio of the physical control domain is verified, and then greedy adjustments and iterative verification are performed on some heliostats in the over-limit physical control domain until all constraints are satisfied.

[0051] Step S5: Identify control line or physical control domain faults The system monitors the status of each physical control domain in real time. Fault determination criteria include (meeting any one of them is sufficient): Communication interruption: No heartbeat signal received for 3 consecutive times; Command timeout: No execution confirmation received within 10 seconds; Tracking deviation: Deviation exceeding 2 mrad and lasting for more than 30 seconds; Power supply abnormality: Current monitoring value is 20% lower than normal value; Fault codes: drive overload, motor stall, etc.

[0052] When a fault occurs, set the fault flag. Record the physical control domain of the fault .

[0053] Step S6: Calculate the partitioned energy flow gap caused by the faulty physical control domain. When physical control domain In the event of a fault, based on the target point allocation scheme and energy flow contribution matrix of the heliostats within the physical control domain before the fault, the energy flow contribution originally borne by each heated zone of the receiver is calculated, and this contribution is used as the energy flow gap for each zone. Receiver Zones The fault energy flow gap is: ; in, Before the malfunction occurred, the heliostat The target point allocation status.

[0054] If partial availability exists Then use: ; in, Indicates heliostat Fully usable This indicates that the device is completely unavailable. This indicates that some parts are available.

[0055] In this embodiment, before the fault control line ROW_A1 fails, it contributes to partitions k_10 and k_11, with gaps of 1200kW and 800kW respectively, and the other partitions contribute a total of 200kW.

[0056] Step S7: Select the group of physically independent compensation lenses Candidate compensated heliostats are selected from the non-faulty physical control domain. Candidate compensated mirror set. The following conditions must be met simultaneously: 1. Not belonging to the fault physical control domain ; 2. with There is no common fault correlation among any given heliostat (i.e.) ); 3. Communication, power supply, and drive status are normal. ); 4. After aligning with the compensation target point, do not exceed the mechanical limit and safety distance; 5. Makes an effective contribution to the region where the energy flow gap is located ( ); 6. The adjustment will not cause thermal safety constraints to exceed the limit (peak energy flow ≤ 800 kW / m). 2 Energy flow gradient ≤ 50 kW / m 2 / m).

[0057] The candidate set of compensated heliostats can be represented as: ; in, Indicates heliostat It meets attitude, safety distance, and thermal safety constraints.

[0058] After screening, 9,500 candidate heliostats were obtained.

[0059] Define compensation variables: ; The compensation optimization objective is: ; in: To compensate for the effect of mirror array on the absorber partition Compensation energy flow: When the compensation heliostat is adjusted from the original target point to the compensation target point, the compensation amount is preferably the net compensation contribution relative to the target point before adjustment, so as to avoid creating new energy flow gaps in other heated zones; ; Indicates heliostat Whether to be selected as a compensating lens (value 0 or 1): ; The compensated thermal risk index; weighting coefficient: .

[0060] A greedy algorithm was used to solve the problem, and 1500 compensating mirrors were finally selected to participate in small-scale, phased adjustments. Their net compensation power is 800 kW for k_10 and 500 kW for k_11, forming a group of compensating mirrors. .

[0061] Step S8: Perform phased switching of compensation target points and closed-loop correction. For the selected compensation mirror group, instead of directly jumping to the new target point, it is gradually adjusted according to the preset time window, energy flow ramping constraints and transition target point sequence.

[0062] Set switching time window Normalized time The transition target point sequence adopts a fifth-degree polynomial: ; in, For heliostats The original target point or original attitude, To compensate for the target point, This is the normalized switching time. This method is used to form a sequence of transition target points to avoid abrupt changes in energy flow during the compensation process.

[0063] The rate of change of energy flow must meet the following constraints: ; For partitioning The maximum allowable rate of change of energy flow is set in this embodiment. The real-time energy flow estimate is updated every 0.5 seconds, and the switching time is automatically extended if the rate of change exceeds the limit.

[0064] Infrared temperature data is continuously collected during the compensation process. If the local temperature exceeds 550°C or the temperature rise rate exceeds 10°C / s, the compensation mirrors are paused and the scheme is recalculated.

[0065] The compensation is considered complete after the energy flow deviation in each zone meets the following conditions and continues for 30 seconds: ; in, Zone the heat absorber Permissible energy flow deviation.

[0066] Fault recovery implementation: Once the faulty physical control domain returns to normal, it is initially marked as "Recovery Observation State" for 5 minutes. After the standard deviation of the tracking error is < 1 mrad, the command response success rate is > 99%, and the communication delay is < 50 ms, the recovery phase begins. Within 120 seconds, the contribution of the compensation mirror group is gradually reduced, and the heliostats in the recovery control row are re-incorporated into the target point allocation according to the physical control domain dispersion constraints. The recovery process also satisfies the energy flow ramping constraint.

[0067] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for stabilizing energy flow in a tower-type photothermal mirror field based on physically connected topology, characterized in that, Includes the following steps: Step S1: Obtain the physical connection properties of the heliostats in the tower-type photothermal mirror field, establish the physical connection topology between the heliostats based on the physical connection properties, and construct one or more physical control domains for heliostats that have common fault correlations. Step S2: Establish the set of receiver heating zones and the set of target points, and calculate the energy flow contribution of each heliostat to each receiver heating zone at different target points, forming the heliostat-target point-receiver zone energy flow contribution matrix; Step S3: During the normal operation of the mirror field, the target point allocation scheme is checked or locally adjusted based on the target energy flow distribution of the receiver and the dispersed constraints of the physical control domain; Step S4: When a failure to track the sun is detected in a certain physical control domain, the energy flow contribution originally undertaken by the faulty physical control domain to each receiver heating zone is calculated based on the target point allocation state of each heliostat in the faulty physical control domain before the failure and the energy flow contribution matrix, and is used as the zone energy flow gap. Step S5: Select candidate compensating heliostats from the non-faulty physical control domains. The candidate compensating heliostats must simultaneously meet the following requirements: they have no common fault correlation with the faulty physical control domain, they have an effective energy flow contribution to the receiver heating zone corresponding to the partitioned energy flow gap, and the adjustment does not cause the receiver thermal safety constraint to exceed the limit. Step S6: Determine the compensation mirror group and its compensation target point based on the energy flow contribution, target point adjustment, physical connection correlation and receiver thermal safety margin of the candidate compensation heliostats; Step S7: According to the energy flow ramping constraint and the phased compensation constraint, send the compensation target point phased adjustment command to the compensation mirror group so that the energy flow distribution of each heated zone of the receiver is restored to the allowable deviation range.

2. The method according to claim 1, characterized in that, The physical connection attributes include at least one of the following: control line number, area control unit number, communication branch number, and power supply branch number; the common fault correlation is determined by at least one of the following: the same control line, the same area control unit, the same communication branch, the same power supply branch, the same control cabinet, or the same network switching node.

3. The method according to claim 1, characterized in that, The physical control domain dispersion constraint refers to limiting the energy flow contribution of the same physical control domain to any receiver heating zone to not exceed a preset threshold, expressed as: ,in, For the first The physical control domain for the first The proportion of energy flow contribution of each heat absorber's heated zone This represents the maximum allowed contribution percentage, i.e., the preset threshold. ； in, For decision variables: ； For heliostats Aim at the target point Heat absorption zone of the heat absorber Energy flow contribution, To prevent extremely small positive numbers with a denominator of zero, M is the total number of target points, and N is the total number of heliostats. For the first One physical control domain.

4. The method according to claim 1, characterized in that, The energy flow contribution matrix is ​​as follows: ； in, Normal direct irradiance, The effective reflective area of ​​the heliostat; For heliostats Aim at the target point Overall optical efficiency at that time; The heliostat's light spot falls into the heat-receiving zone of the receiver. The energy flow distribution coefficient.

5. The method according to claim 1, characterized in that, In step S3, the target point for verification or partial adjustment during normal operation is represented as follows: ； in, Heat absorption zone for heat absorber The target energy flow; This represents the total attitude adjustment amount for switching the target point of the heliostat. Heat absorption zone for heat absorber thermal risk indicators Heat absorption zone for heat absorber The actual energy flow, For the first Each physical control domain controls the heat receiving zone of the receiver. The proportion of energy flow contribution, The maximum allowable contribution percentage, i.e., the preset threshold. , , , These are the weighting coefficients.

6. The method according to claim 1, characterized in that, The calculation method for the energy flow gap in the partition is as follows: Heat receiver heating partition The fault energy flow gap is: ； in, Before the malfunction occurred, the heliostat Target point allocation status; For heliostats Aim at the target point Heat absorption zone of the heat absorber Energy flow contribution; If some heliostats are not completely inoperable, but still have some usability Then the heat absorber is heated in a specific zone. The fault energy flow gap is: ； in, Indicates heliostat Fully usable This indicates that it is completely unavailable. This indicates that some parts are available.

7. The method according to claim 1, characterized in that, The selection of candidate compensation heliostats is achieved through the following optimization objectives: ； in, For the fault energy flow gap, To compensate for energy flow, This is the heliostat attitude adjustment amount. The thermal risk index after compensation. For the physical connectivity matrix, Indicates heliostat Whether it was selected as a compensating lens and: ； To compensate for the allocation variables: ； , which represents the weighting coefficient; the last term is used to suppress the concentration of compensation mirror clusters in the same physical control domain.

8. The method according to claim 7, characterized in that, Compensating mirror group for receiver partitioning The compensation energy flow is: ； in, For the candidate compensation heliostat set, For heliostats Aim at the target point Heat absorption zone of the heat absorber Energy flow contribution.

9. The method according to claim 1, characterized in that, The phased adjustment command for the compensation target point is generated using a fifth-order polynomial trajectory or energy flow ramp control, ensuring that the energy flow change rate of each zone of the receiver does not exceed the preset maximum energy flow change rate. ； in, for Current heat absorber partition The actual energy flow, for Current heat absorber partition The actual energy flow, Zone the heat absorber Maximum permissible rate of change of energy flow.

10. The method according to claim 1, characterized in that, Once the faulty physical control domain returns to normal, it is first marked as a restored observation state. After it meets at least one of the recovery conditions of tracking error, communication quality, and drive response time, the compensation contribution of the compensation mirror group is gradually reduced, and the heliostats in the restored control domain are gradually reintegrated into the target point allocation. The recovery process also satisfies the energy flow ramp-up constraint and the phased compensation constraint.

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