Method for regulating the energy flux density distribution of a concentrated solar furnace device

Abstract

This invention discloses a method for controlling the energy flux density distribution of a concentrating solar furnace device. The method includes: constructing an optical system model of the concentrating solar furnace device; determining an energy flux density distribution control model based on the optical system model, according to the cross-offset parameter within the light focusing point of the reactor, the position parameter of the heat-absorbing platform where the reactor is located, and the curvature parameter of the concentrating mirror; determining control parameters of the concentrating solar furnace device based on the energy flux density distribution control model, according to the set target region size, the peak energy flux control range within the target region, and the range of non-uniformity factors of the energy flux distribution within the target region, combined with the direct normal irradiance (DNI) parameter; the target region is the preset area to be focused by the reflected light; and controlling the operating state of the corresponding components of the concentrating solar furnace device according to the control parameters. This invention solves the problem that existing control methods are insufficient to achieve the desired control of thermochemical reaction products.

Description

Technical Field

[0001] This invention relates to the field of thermochemical technology, and in particular to a method for controlling the energy flux density distribution of a concentrating solar furnace device. Background Technology

[0002] In response to the needs of green and low-carbon transformation, it is essential to conduct research on solar concentrating high-temperature heating technology and develop key technologies for replacing fossil fuels in combination with other industries. However, current concentrating solar devices are characterized by discontinuous energy flow, high heat flow, and non-uniformity.

[0003] Currently, most existing concentrating solar furnace devices consist of a primary plane mirror and a secondary rotating parabolic concentrator. One of the application goals of reflective solar furnaces is to achieve thermochemical reactions. Studying the thermochemical reaction mechanism can provide a theoretical basis for the application of reflective solar furnaces, but thermochemical reactions are extremely sensitive to temperature changes.

[0004] Concentrated solar furnaces are a key piece of equipment in the field of solar thermochemistry, which uses focused solar energy to drive reactors for thermochemical reaction research. The energy flux density distribution characteristics on the reactor surface play a decisive role in the regulation of the thermochemical reaction process and the generation of target products. After testing existing technologies, it was found that existing control methods are difficult to meet the requirements of uniformity and stability of focused energy flux density distribution for solar thermochemical reactions, and thus it is difficult to achieve the purpose of regulating the target products of thermochemical reactions. Summary of the Invention

[0005] This invention provides a method for regulating the energy flux density distribution of a concentrating solar furnace device, which solves the problem that existing regulation methods are difficult to meet the requirements of uniformity and stability of the focused energy flux density distribution for solar thermochemical reactions, and thus difficult to achieve the purpose of regulating the target products of thermochemical reactions.

[0006] A method for controlling the energy flux density distribution of a concentrating solar furnace device includes:

[0007] Construct an optical system model for a concentrating solar furnace device;

[0008] Based on the optical system model, the energy flux density distribution control model is determined according to the cross offset parameter within the light focal point of the reactor, the position parameter of the heat absorption platform where the reactor is located, and the curvature parameter of the condenser lens.

[0009] Based on the energy flux density distribution control model, the control parameters of the concentrating solar furnace device are determined according to the set target area size, the peak energy flux control range within the target area, and the range of non-uniformity factors of energy flux distribution within the target area, combined with the direct normal irradiance (DNI) parameter; the target area is the area to be focused by the preset reflected light.

[0010] The operating status of the corresponding components of the concentrating solar furnace device is adjusted according to the control parameters.

[0011] In one embodiment of the present invention, the construction of the optical system model of the concentrating solar furnace device specifically includes: establishing a solar model, a heliostat reflection model, a concentrating mirror focusing model, and a reactor surface receiving model in a global coordinate system; establishing a reactor surface energy flux density distribution calculation model in a local coordinate system; and constructing the optical system model of the concentrating solar furnace device based on the solar model, the heliostat reflection model, the concentrating mirror focusing model, the reactor surface receiving model, and the reactor surface energy flux density distribution calculation model.

[0012] In one embodiment of the present invention, the optical system model for constructing the concentrating solar furnace device further includes: using the apex O of the secondary concentrator mirror. j Establish a global coordinate system (X) for the origin. j Y j Z j ); where X j The axis points due east, Y j The axis points to the focal point of the condenser lens, Z. j The axis points towards the zenith; based on the north-south orientation of the concentrating solar furnace, the coordinates of the center point of the heliostat in the global coordinate system are represented as (0, Y). j，heliostat ,0), where Y j，heliostat The origin of the global coordinate system and the center point of the heliostat are in the Y-axis. j The distance on the axis; the coordinates of the center point of the heat absorption platform are represented as (0, Y). j，platform ,0),Y j，platform Let the origin of the global coordinate system and the center point of the heat absorption platform be in the Y-axis. j On-axis distance; with the center point of the heat absorption platform (0, Y) j，platform Establish a local coordinate system (X, 0) with the origin as the origin. t Z t ), where X t With X j Same direction, Z t With Z j Same direction.

[0013] In one embodiment of the present invention, the condenser in the focusing model is a four-quadrant adjustable-focus secondary condenser; the heliostat in the reflection model is a primary heliostat used to reflect the solar beam emitted from the solar model; establishing the focusing model specifically includes: the solar beam emitted from the solar model is reflected by the primary heliostat to the secondary condenser; the secondary condensers in each quadrant converge the parallel light reflected by the primary heliostat; the direction vector of the light reflected by the secondary condenser is determined according to the law of specular reflection; and the focusing model of the secondary condenser in each quadrant is determined according to the direction vector.

[0014] In one embodiment of the present invention, determining the energy flux density distribution control model based on the cross-offset parameter within the focal point of the reactor, the position parameter of the heat-absorbing platform where the reactor is located, and the curvature parameter of the condenser mirror specifically includes: optimizing the position parameter of the heat-absorbing platform, the cross-offset parameter within the focal point of the reactor, and the curvature parameter of the condenser mirror in the optical system model of the concentrating solar furnace device. The optimized energy flux density distribution control model is expressed as follows:

[0015] Find X = [YJP or L1 or G1]

[0016]

[0017] stF min ≤F peak ≤F max

[0018] In the formula: X is the control variable matrix of the concentrating solar furnace device; YJP is the heat absorption platform along the Y-axis in the global coordinate system. j The displacement variable matrix in the direction, YJP = [YJP1, YJP2, ..., YJP] k , ..., YJP K L1 is the inner cross offset matrix of the secondary condenser lenses in each quadrant, which is improved by the secondary condenser lens focus point offset strategy and converges in the local coordinate system. L1 = [l1, l2, ..., l k , ..., l K ], where, inner cross offset / inner cross is the equal inner cross offset of the focal points corresponding to the four quadrants of the secondary condenser from the center point of the heat absorption platform to directions of 45°, 135°, 225° and 315° respectively, where L represents the distance, also known as the inner cross offset distance / focal point inner cross offset parameter; G1 is the curvature variable matrix that changes the curvature of the secondary condenser mirror surface in each quadrant through the turntable support, G1=[g1,g2,…,g k , ..., g K F(X) is the non-uniformity factor of the energy flux density distribution within the target region, and serves as the objective function; NDt The number of discrete mesh cells whose center point is within the target region; meshes satisfying this condition are also called target mesh elements i; F Dti The energy flux density value of target grid cell i, in kW / m³. 2 ;F Dta To regulate the average energy flux density within the target area, the unit is kW / m³. 2 ;F peak F represents the peak energy flux within the target region. min With F max The set peak energy flow control range.

[0019] In one embodiment of the present invention, the determination of the control parameters of the concentrating solar furnace device based on the energy flux density distribution control model according to the set target region size, the peak energy flux control range within the target region, and the range of non-uniformity factors of energy flux distribution within the target region, combined with the direct normal irradiance (DNI) parameter, includes: combining the energy flux density distribution control model with a genetic algorithm for parameter optimization, with the minimum objective function F(X) value as the optimization objective, to optimize and solve the system control parameters; wherein, in the genetic algorithm, the fitness function of individual j is:

[0020]

[0021] In the formula: F e For fitness, F(X) j fn is the non-uniformity factor of the energy flux density distribution within the target region corresponding to individual j in the population. one It is the maximum estimate of the objective function value;

[0022] The optimal control parameters for fitness are determined based on the different attributes of the DNI parameters.

[0023] In one embodiment of the present invention, determining the control parameter corresponding to the optimal fitness based on different attributes of the DNI parameter specifically includes: when the DNI parameter is a constant, determining the control parameter corresponding to the minimum non-uniformity factor; when the DNI parameter is a variable, determining the control parameter that meets the non-uniformity factor range constraint and has optimal fitness.

[0024] In one embodiment of the present invention, the energy flux density distribution control model is combined with a genetic algorithm for parameter optimization. The optimization objective is to minimize the value of the objective function F(X). Specifically, this includes: updating the parameters of the energy flux density distribution control model based on the optimal control parameters to obtain an updated parameter solution set and acquiring the current update count. The update includes at least crossover, mutation, and selection operations. A first device control parameter is determined based on the current update count, and a first energy flux density distribution is calculated based on the current update count and the first device control parameter. A corresponding target displacement vector is determined based on the first energy flux density distribution. The target displacement vector is superimposed on the first device control parameter to recalculate a second energy flux density distribution. A corresponding second device control parameter is determined based on the second energy flux density distribution. The second device control parameter is used as the first device control parameter for the next iteration.

[0025] An apparatus for controlling the energy flux density distribution of a concentrating solar furnace device as described above, comprising:

[0026] The optical system model building module is used to build the optical system model of the concentrating solar furnace device;

[0027] The control model construction module is used to determine the energy flux density distribution control model based on the optical system model, according to the cross offset parameter within the light focal point of the reactor, the position parameter of the heat absorption platform where the reactor is located, and the curvature parameter of the condenser lens.

[0028] The control parameter calculation module is used to determine the control parameters of the concentrating solar furnace device based on the energy flux density distribution control model, according to the set target area size, the peak energy flux control range within the target area, and the range of non-uniformity factors of energy flux distribution within the target area, combined with the direct normal irradiance (DNI) parameter; the target area is the area to be focused by the preset reflected light.

[0029] The control module is used to control the working status of corresponding components of the concentrating solar furnace device according to the control parameters.

[0030] An apparatus for controlling the energy flux density distribution of a concentrating solar furnace device as described above, comprising:

[0031] At least one processor; and,

[0032] The memory is communicatively connected to the at least one processor via a bus; wherein,

[0033] The memory stores instructions that can be executed by the at least one processor to implement the method as described in any of the above embodiments.

[0034] This invention provides a method for controlling the energy flux density distribution of a concentrating solar furnace device, which has at least the following beneficial effects:

[0035] 1. The energy flux density control method provided by this invention combines genetic algorithm with ray tracing method, takes into account the changes in DNI during the day, and comprehensively optimizes control parameters such as cross offset within the focal point, position of the heat absorption platform, and mirror curvature of the secondary condenser. This provides control parameters for achieving the set peak range and uniform distribution of energy flux density within the target area, thereby meeting the requirements of solar thermochemical reaction for the uniformity and stability of focused energy flux density distribution, and thus achieving the purpose of controlling the target product of thermochemical reaction.

[0036] 2. The energy flux density control method provided by this invention, which controls the peak energy flux density required to meet the thermochemical reaction field, can improve the direct usable energy ratio and thus improve energy utilization compared to the original solar furnace device. Attached Figure Description

[0037] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0038] Figure 1 A schematic diagram illustrating the steps of a method for controlling the energy flux density distribution of a concentrating solar furnace device according to an embodiment of the present invention;

[0039] Figure 2 A schematic diagram of the optical system model of a concentrating solar furnace device based on a three-dimensional coordinate system provided in an embodiment of the present invention;

[0040] Figure 3 This is a schematic diagram of the grid division on the reactor surface provided in an embodiment of the present invention;

[0041] Figure 4 This is a schematic diagram of the in-focus cross offset and outward expansion offset provided in an embodiment of the present invention;

[0042] Figure 5 A flowchart of energy flow regulation combining ray tracing and genetic algorithms is provided for embodiments of the present invention.

[0043] Figure 6 The DNI provided for this embodiment of the invention is 480W / m 2 Y j，platform A schematic diagram of the adjustment simulation results with a focal length of 5.19m and an inter-point offset of 0.08m.

[0044] Figure 7 The DNI provided for this embodiment of the invention is 800W / m 2 Yj，platform A schematic diagram of the adjustment simulation results with a focal length of 5.22m and an inter-point offset of 0.07m.

[0045] Figure 8 Comparison diagrams before and after optimization for examples provided in embodiments of the present invention;

[0046] Figure 9 A schematic diagram of an energy flux density distribution control device for a concentrating solar furnace provided in an embodiment of the present invention;

[0047] Figure 10 This is a schematic diagram of an energy flux density distribution control device for a concentrating solar furnace provided in an embodiment of the present invention. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described clearly and completely below in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0049] It should be noted that those skilled in the art will understand, explicitly and implicitly, that the embodiments described in this invention can be combined with other embodiments without conflict. Unless otherwise defined, the technical or scientific terms used in this invention should be understood in their ordinary sense by those skilled in the art. The terms "a," "an," "an," "the," etc., used in this invention do not indicate quantity limitation and can represent singular or plural. The terms "comprising," "including," "having," and any variations thereof used in this invention are intended to cover non-exclusive inclusion; the terms "first," "second," "third," etc., used in this invention are merely to distinguish similar objects and do not represent a specific ordering of objects.

[0050] This invention proposes a method for controlling the energy flux density distribution of a concentrating solar furnace device. The details are described below.

[0051] Figure 1 A schematic diagram illustrating the steps of a method for controlling the energy flux density distribution of a concentrating solar furnace device according to an embodiment of the present invention may include the following steps:

[0052] S110: Construct an optical system model for a concentrating solar furnace device.

[0053] In one embodiment of the present invention, constructing an optical system model of a concentrating solar furnace device specifically includes: establishing a solar model, a heliostat reflection model, a concentrating mirror focusing model, and a reactor surface receiving model in a global coordinate system; establishing a reactor surface energy flux density distribution calculation model in a local coordinate system; and constructing the optical system model of the concentrating solar furnace device based on the solar model, the heliostat reflection model, the concentrating mirror focusing model, the reactor surface receiving model, and the reactor surface energy flux density distribution calculation model.

[0054] In one embodiment of the present invention, constructing an optical system model of a concentrating solar furnace device further includes: using the vertex O of a secondary concentrator mirror... j Establish a global coordinate system (X) for the origin. j Y j Z j ); where X j The axis points due east, Y j The axis points to the focal point of the condenser lens, Z. j The axis points towards the zenith; based on the north-south orientation of the concentrating solar furnace, the coordinates of the center point of the heliostat in the global coordinate system are represented as (0, Y). j，heliostat ,0), where Y j，heliostat The origin of the global coordinate system and the center point of the heliostat are in the Y-axis. j The distance on the axis; the coordinates of the center point of the heat absorption platform are represented as (0, Y). j，platform ,0),Y j，platform Let the origin of the global coordinate system and the center point of the heat absorption platform be in the Y-axis. j On-axis distance; with the center point of the heat absorption platform (0, Y) j，platform Establish a local coordinate system (X, 0) with the origin as the origin. t Z t ), where X t With X j Same direction, Z t With Z j Same direction.

[0055] In one embodiment of the present invention, the condenser in the focusing model is a four-quadrant adjustable-focus secondary condenser; the heliostat in the reflection model is a primary heliostat used to reflect the solar beam emitted from the solar model; establishing the focusing model specifically includes: the solar beam emitted from the solar model is reflected by the primary heliostat to the secondary condenser; the secondary condensers in each quadrant converge the parallel light reflected by the primary heliostat; the direction vector of the light reflected by the secondary condenser is determined according to the law of specular reflection; and the focusing model of the secondary condenser in each quadrant is determined according to the direction vector.

[0056] Specifically, such as Figure 2As shown, the optical system model of the solar furnace device is constructed by establishing a solar model, a heliostat reflection model, a condenser focusing model, a reactor surface receiving model in the global coordinate system, and a reactor surface energy flux density distribution calculation model in the local coordinate system. The various models mentioned above are described below.

[0057] (1) Solar Model

[0058] The direction cosine of the incident sunlight can be expressed as:

[0059]

[0060] Since tracking errors are not considered, the direction cosine of the sunlight reflected by the heliostat in the global coordinate system can be expressed as:

[0061]

[0062]

[0063] ψ1=2πε2

[0064] In the formula: ε1 and ε2 are random numbers between 0 and 1; σ max λ1 represents the incident solar cone angle, which is 9.3 mrad; λ1 represents the radial angle of the solar cone, in rad; ψ1 represents the circumferential angle of the solar cone, in rad.

[0065] (2) Heliostat Reflection Model

[0066] To establish a heliostat reflection model with a tracking strategy, after obtaining the sun's position, the direction vector of the heliostat normal is determined based on the direction vectors of the incident and outgoing rays. Its expression is:

[0067]

[0068]

[0069] In the formula: The vector representing the direction of the central ray of the light cone after reflection by the heliostat. θs is the angle between the heliostat normal and the incident ray.

[0070] According to Y j，heliostat The expression for a single-stage heliostat model is determined as follows:

[0071]

[0072] Taking any intersection point P0 = (x0, y0, z0) between the incident sunlight and the heliostat as an example, the expression for the parametric equation of the reflected beam is:

[0073]

[0074] In the formula: x j，h2c y j，h2c , z j，h2c t1 represents the coordinates of the reflected ray from the heliostat to the secondary condenser; t1 is a parameter.

[0075] (3) Condenser lens focusing model

[0076] The four-quadrant adjustable-focus secondary condenser converges the parallel light reflected from the primary heliostat through the secondary condenser mirrors in each quadrant. Therefore, the surface equations for the secondary condenser mirrors in each quadrant are as follows:

[0077] a i (Xx t，Rei ) 2 +b i (Zz t，Rei ) 2 =4f i Y

[0078] In the formula: a i b i The curvature parameters of the secondary condenser mirrors are changed in each quadrant respectively; x t，Rei , z t，Rei The secondary condenser lenses in each quadrant are focused onto the local plane coordinate system (X). t Z t The positional parameter in ); f i To change the focal length parameter of the secondary condenser surface equation in each quadrant, the unit is m; i takes the values ​​1, 2, 3, and 4, representing the quadrant in which it is located.

[0079] The sunlight beam is reflected by a heliostat to a secondary concentrator. Taking any point P1 = (x1, y1, z1) as an example, the direction vector expression of the normal to point P1 is:

[0080]

[0081] According to the law of specular reflection, the direction vector of light rays after reflection by a secondary condenser mirror can be expressed as:

[0082]

[0083] Finally, the parametric equations for the focusing models of the secondary condenser lenses in each quadrant, i.e., the focused rays, are as follows:

[0084]

[0085] In the formula: x j，c2 y j，c2p , zj，c2p t1 represents the coordinates of the reflected ray from the condenser to the heat-absorbing platform; t2 is a parameter.

[0086] (4) Reactor surface receiving model

[0087] Since the reactor surface is considered as an ideal planar receiving window, the expression for the reactor surface receiving model is as follows:

[0088] Y+Y j，platform =0

[0089] (5) Energy flux density distribution calculation model

[0090] Based on the ray tracing method, the number of rays that finally reach the reactor surface calculation area after reflection by the mirror is counted. To obtain the energy flux density distribution on the reactor surface, the energy I0 carried by each ray must first be calculated, and its expression is:

[0091]

[0092] In the formula: S h The projected area of ​​the heliostat on the cutoff plane of the secondary condenser is expressed in m². 2 η1 is the reflectivity of a primary heliostat; η 2，i Let i be the reflectivity of the secondary condenser lens in each quadrant, where i takes values ​​of 1, 2, 3, and 4; N t ηt represents the total number of rays being traced; η3 represents the cosine loss, which is the reduction in received energy caused by the non-parallelism between the incident direction of sunlight and the normal direction of the mirror aperture. Its expression is:

[0093]

[0094] Secondly, the square planar receiving window of the reactor is discretized into many square grid cells of equal area, such as... Figure 3 As shown, that is: in the local coordinate system (X t Z t In the process of constructing a region, a square region with a side length of D0 is selected centered at the origin of the local coordinate system. This region is then discretized into a square grid (M = N). An array F1(M, N) is defined to store the energy of each grid region, where F1(1, 1) and F1(m, n) represent elements of this array, and D0 is the side length of the reactor. constraint D represents the side length of the focused spot within the divided square region. target This represents the side length of the control target area set within the divided square region, typically D. target ≤D constraint ≤D0.

[0095] The light rays focused by the condenser lens and the reactor surface are aligned in the global coordinate system (X). j Y j Z j The intersection points of the coordinate systems (x, y, z) are as follows. Taking any point P2 = (x2, y2, z2) as an example, the coordinates of this point in the local plane coordinate system (X... t Z t In this context, it is represented as P. t2 =(x t2 , z t2 The grid number to which this point belongs is identified according to the following formula:

[0096]

[0097] When M and N satisfy the above formula, the grid is assigned an energy value F1(M, N) = F1(M, N) + I0. Finally, through the above intersection calculation, subordinate grid region identification, and energy accumulation, and by statistically analyzing the energy received by each grid region on the reactor surface, the energy flux density distribution on the reactor surface is obtained.

[0098] S120: Based on the optical system model, the energy flux density distribution control model is determined according to the cross offset parameters within the light focal point of the reactor, the position parameters of the heat absorption platform where the reactor is located, and the curvature parameters of the condenser lens.

[0099] Specifically, considering that the non-uniformity factor and the direct useful energy ratio are contradictory performance parameters, if both are taken as objective functions, the optimization problem will be a multi-objective optimization problem. However, considering that the reaction area of ​​the thermochemical reaction in the reactor is established within the target region, more emphasis is placed on the uniformity of energy flux density distribution and its sensitivity to temperature. Therefore, the uniformity of energy flux density distribution is taken as the only objective function, while peak regulation is taken as a constraint, thus transforming the multi-objective optimization problem into a single-objective optimization problem and simplifying the mathematical model of optimization.

[0100] In one embodiment of the present invention, an energy flux density distribution control model is determined based on the cross-offset parameter within the light focal point of the reactor, the position parameter of the heat-absorbing platform where the reactor is located, and the curvature parameter of the condenser mirror. Specifically, this includes optimizing the position parameter of the heat-absorbing platform, the cross-offset parameter within the focal point of the reactor, and the curvature parameter of the condenser mirror in the optical system model of the concentrating solar furnace device. The optimized energy flux density distribution control model is expressed as follows:

[0101] Find X = [YJP or L1 or G1]

[0102]

[0103] stF min ≤F peak ≤Fmax

[0104] In the formula: X is the control variable matrix of the concentrating solar furnace device; YJP is the heat absorption platform along the Y-axis in the global coordinate system. j The displacement variable matrix in the direction, YJP = [YJP1, YJP2, ..., YJP] k , ..., YJP k L1 is the inner cross offset matrix of the secondary condenser lenses in each quadrant, which is improved by the secondary condenser lens focus point offset strategy and converges in the local coordinate system. L1 = [l1, l2, ..., l k , ..., l K ], where, inner cross offset / inner cross is the equal inner cross offset of the focal points corresponding to the four quadrants of the secondary condenser from the center point of the heat absorption platform to directions of 45°, 135°, 225° and 315° respectively, where L represents the distance, also known as the inner cross offset distance / focal point inner cross offset parameter; G1 is the curvature variable matrix that changes the curvature of the secondary condenser mirror surface in each quadrant through the turntable support, G1=[g1,g2,…,g k , ..., g K F(X) is the non-uniformity factor of the energy flux density distribution within the target region, and serves as the objective function; N Dt The number of discrete mesh cells whose center point is within the target region; meshes satisfying this condition are also called target mesh elements i; F Dti The energy flux density value of target grid cell i, in kW / m³. 2 ;F Dta To regulate the average energy flux density within the target area, the unit is kW / m³. 2 ;F peak F represents the peak energy flux within the target region. min With F max The set peak energy flow control range.

[0105] Specifically, an energy flux density distribution control model is constructed based on the cross-offset parameters within the focal point, the position parameters of the heat-absorbing platform, and the curvature parameters of the concentrating mirror. By optimizing the position parameters of the heat-absorbing platform, the cross-offset parameters within the focal point, and the curvature parameters of the mirror in the adjustable coke-type concentrating solar furnace, the target area on the reactor surface is achieved. Figure 3 The side length of the square is D target To homogenize the energy flux density distribution within a region, its optimized mathematical model can be expressed as:

[0106] Find X = [YJP or L1 or G1]

[0107]

[0108] stF min≤F peak ≤F max

[0109] In the formula: X is the decision variable matrix, i.e., the control variables of the concentrated solar furnace; Y j，p The heat absorption platform is along the Y-axis in the global coordinate system. j The displacement variable matrix in the direction, YJP = [YJP1, YJP2, ..., YJP] k , ..., YJP k L1 is the inner cross offset matrix of the secondary condenser lenses in each quadrant, which is improved by the secondary condenser lens focus point offset strategy and converges in the local coordinate system. L1 = [l1, l2, ..., l k , ..., l K G1 is the curvature variable matrix of the secondary condenser lenses in each quadrant, which is changed by the turntable support. G1 = [g1, g2, ..., g...]. k , ..., g K F(X) is the objective function, i.e., the non-uniformity factor of energy flux distribution within the target region; N Dt The center point of the discrete grid is on a side of length D. target The number of grid cells within a square; a grid cell satisfying this condition is also called the target grid cell, F. Dti The energy flux density value of target grid cell i, in kW / m³. 2 ;F Dta To regulate the average energy flux density within the target area, the unit is kW / m³. 2 ;F peak F represents the peak energy flux within the target region. min With F max It is the set peak energy flow control range, which meets F min ≤F peak ≤F max Under these conditions, the parameters YJPk and l of the four-quadrant adjustable focus concentrating solar furnace device can be determined for different DNIs. K and g K The value of (i.e., the value of the optimized control parameter).

[0110] Among them, such as Figure 4 As shown, the inner cross offset is to offset the focal points corresponding to the four quadrants of the secondary condenser lens by equal distances from the center point of the heat absorption platform in the directions of 45°, 135°, 225° and 315° respectively. L represents the distance, also known as the distance / focal point inner cross offset parameter of the inner cross offset.

[0111] S130: Based on the energy flux density distribution control model, the control parameters of the concentrating solar furnace device are determined according to the set target area size, the peak energy flux control range within the target area, and the range of non-uniformity factors of energy flux distribution within the target area, combined with the direct normal irradiance (DNI) parameter. The target area is the area to be focused by the preset reflected light.

[0112] In one embodiment of the present invention, the control parameters of a concentrating solar furnace device are determined based on an energy flux density distribution control model according to the set target region size, the peak energy flux control range within the target region, and the range of non-uniformity factors of energy flux distribution within the target region, combined with the direct normal irradiance (DNI) parameter. This includes: combining the energy flux density distribution control model with a genetic algorithm for parameter optimization, with the minimum objective function F(X) value as the optimization objective, to optimize and solve the system control parameters; wherein, in the genetic algorithm, the fitness function of individual j is:

[0113]

[0114] In the formula: F e For fitness, F(X) j f is the non-uniformity factor of the energy flux density distribution within the target region corresponding to individual j in the population. none It is the maximum estimate of the objective function value;

[0115] The optimal control parameters for fitness are determined based on the different attributes of the DNI parameters.

[0116] In one embodiment of the present invention, the control parameter corresponding to the optimal fitness is determined according to different attributes of the DNI parameter, specifically including: when the DNI parameter is a constant, determining the control parameter corresponding to the minimum non-uniformity factor; when the DNI parameter is a variable, determining the control parameter that meets the non-uniformity factor range constraint and has the optimal fitness.

[0117] Specifically, such as Figure 5 The flowchart shown illustrates the energy flow regulation process using ray tracing and genetic algorithms. It combines the constructed optimized mathematical model with the genetic algorithm, optimizing parameters with the minimum objective function F(X). In the genetic algorithm, the fitness function of individual j is:

[0118]

[0119] In the formula: F(X) j ) is the non-uniformity factor of energy flux distribution within the target region corresponding to individual j in the population; f none It is the maximum estimate of the objective function value.

[0120] In each iteration of the genetic algorithm, the current fitness is detected, and the current fitness is matched with the historical best fitness of the target energy flux density distribution. That is, when the DNI parameter is set to a fixed value, the control parameter corresponding to the minimum non-uniformity factor (when the fitness is optimal) is determined as the optimal control parameter. When the DNI is set to a variable value, the range of the non-uniformity factor is fixed regardless of how the DNI parameter changes. For example, if the non-uniformity factor is set to be less than 0.1, then the constraint is that the non-uniformity factor value obtained according to the control parameter must be less than 0.1. Based on the above constraints, the optimal fitness value calculated during the matching optimization process is matched, and the control parameter corresponding to the optimal fitness is taken as the optimal control parameter.

[0121] In one embodiment of the present invention, the energy flux density distribution control model is combined with a genetic algorithm for parameter optimization. The optimization objective is to minimize the value of the objective function F(X). Specifically, this includes: updating the parameters of the energy flux density distribution control model based on the optimal control parameters to obtain an updated parameter solution set and acquiring the current update count. The update includes at least crossover, mutation, and selection operations. A first device control parameter is determined based on the current update count, and a first energy flux density distribution is calculated based on the current update count and the first device control parameter. A corresponding target displacement vector is determined based on the first energy flux density distribution. The target displacement vector is superimposed on the first device control parameter to recalculate a second energy flux density distribution. A corresponding second device control parameter is determined based on the second energy flux density distribution. The second device control parameter is used as the first device control parameter for the next iteration.

[0122] For example, if the device parameter to be prioritized for optimization in this iteration is determined to be the heat-absorbing platform position parameter based on the current update count, then the heat-absorbing platform position parameter is used as the first device control parameter. The energy flow density distribution after control is calculated based on the heat-absorbing platform position parameter, and the heat-absorbing platform displacement vector (target displacement vector) is determined. The heat-absorbing platform displacement vector is superimposed on the heat-absorbing platform displacement parameter, indicating that the heat-absorbing platform position parameter of the previous iteration has been optimized. At this time, the energy flow density distribution on the reactor is recalculated to obtain the inner cross offset parameter (second device control parameter).

[0123] Based on the above process, a new iteration is performed. The inner cross offset parameter obtained in the previous iteration is used as the first device control parameter. The energy flux density distribution after control is calculated based on the inner cross offset parameter. The displacement vector of the inner cross offset at the focal point (target displacement vector) is determined. The displacement vector of the inner cross offset at the focal point is superimposed on the inner cross offset parameter, indicating that the inner cross offset parameter of the previous iteration has been optimized. At this time, the energy flux density distribution on the reactor is recalculated as the endothermic platform position parameter (second device control parameter). The endothermic platform position parameter is used as the basis for the next iteration.

[0124] S 140: Adjust the working status of the corresponding components of the concentrating solar furnace device according to the control parameters.

[0125] Specifically, the control object is determined based on the relationship between the energy flux density distribution state data in the target area and the preset expected value of the energy flux density distribution. The control object includes the cross offset parameter within the focal point, the position parameter of the heat absorption platform, or the curvature parameter of the condenser lens. The adjustment range of the control object is determined based on the final energy flux density distribution state data and the energy flux density distribution control model.

[0126] Furthermore, after training the energy flux density distribution control model, the DNI value, the cross-offset parameter within the focal point, the position parameter of the heat absorption platform, and the curvature parameter of the condenser lens are sampled at a certain moment. The DNI value, the cross-offset parameter within the focal point, the position parameter of the heat absorption platform, and the curvature parameter of the condenser lens are then input into the energy flux density distribution control model to obtain the predicted energy flux density distribution within the target area. This allows staff to intuitively see the control effect and facilitates analysis and adjustment.

[0127] The operating status of corresponding components of the solar furnace device is regulated based on the control parameters. According to the set control target, the calculated control parameters can be transmitted to the controller in real time to regulate the system parameters of the concentrating solar furnace device in order to obtain the desired adjustment target.

[0128] In one embodiment of the present invention, under clear weather conditions, the solar furnace device struggles to consistently provide a range of energy flux density distributions due to the daily variation in DNI values ​​over time. However, solar-assisted biomass gasification can stably control the energy flux density between 3000 and 3300 kW / m³. 2 Therefore, taking the parameters of a solar furnace in Yanqing, Beijing (latitude: 40.32°, longitude: 116.01°) as an example, the heliostat mirror has a length and width of 10.50m and the secondary concentrator has a focal length of 5.30m. The DNI simulation curve of the vernal equinox (March 21st) is selected to analyze the energy flow distribution control calculation. A 10cm square aperture is used as the target area. Although the curvature of the secondary concentrator in the solar furnace can be adjusted in real time via a turntable, considering the mechanical delay and the difficulty of actual operation, only the position parameters of the heat absorption platform and the inner cross offset parameters in the control optimization model are considered for dynamic optimization control. That is, G1 is not involved in the optimization solution in this case, with the energy flow density stably controlled at 3000-3300kW / m². 2 To achieve the desired control target, DNI is set at 480-800 W / m. 2 Fluctuating between, and at 20W / m 2 To maintain the energy flux density non-uniformity factor below 0.10, optimization was performed, where the DNI was 480 Wm. 2Y j，paltform The simulation results of the energy flux density distribution when the focal point is 5.22m and the cross offset is 0.07 are shown in the figure below. Figure 6 As shown, when DNI is 800W / m 2 Y j，platform The energy flux density distribution diagram when the focal point cross offset is 0.08 and the focal length is 5.19m is shown in the figure. Figure 7 As shown.

[0129] Furthermore, by comparing it with the original solar furnace without the optimized control strategy when the DNI is 480-800W / m 2 When the DNI fluctuates between these values, the median fluctuation is 640 W / m. 2 Peak hourly energy flow is close to 3300 kW / m 2 The peak fluctuation of the reactor surface energy flux density at point 5.23 is used as a comparison, and the comparison results before and after optimization are as follows: Figure 8 As shown, by incorporating the energy flow regulation method of this invention, the non-uniformity factor of the energy flow density distribution in the target area can be less than 0.10, and the peak fluctuation can be within 10.00%, while the energy flow fluctuation without the addition is 70.00%. At the same time, the optimized regulation parameters can significantly improve the direct usable energy ratio in the target area and improve energy utilization.

[0130] The above describes a method for controlling the energy flux density distribution of a concentrating solar furnace device according to an embodiment of the present invention. Based on the same inventive concept, the present invention also provides a corresponding device that applies the above-described method for controlling the energy flux density distribution of a concentrating solar furnace device, such as... Figure 9 As shown.

[0131] The optical system model construction module 902 is used to construct the optical system model of the concentrating solar furnace device; the control model construction module 904 is used to determine the energy flux density distribution control model based on the optical system model, according to the cross offset parameter within the light focal point of the reactor, the position parameter of the heat absorption platform where the reactor is located, and the curvature parameter of the condenser mirror; the control parameter calculation module 906 is used to determine the control parameters of the concentrating solar furnace device based on the energy flux density distribution control model, according to the set target area size, the peak energy flux control range within the target area, and the non-uniformity factor range of the energy flux distribution within the target area, combined with the direct normal irradiance (DNI) parameter; the target area is the preset area to be focused by the reflected light; the control module 908 is used to control the working state of the corresponding components of the concentrating solar furnace device according to the control parameters.

[0132] This invention also provides a corresponding device for controlling the energy flux density distribution of the above-described concentrating solar furnace device, such as... Figure 10 As shown, it includes:

[0133] The system includes at least one processor 1002, a communication interface 1004, a memory 1006, and a communication bus 1008; wherein the processor 1002, the communication interface 1004, and the memory 1006 communicate with each other through the communication bus 1008; the processor 1002 can call logical instructions stored in the memory 1006 to cause at least one processor 1002 to execute the steps of the above embodiments.

[0134] Based on the same idea, some embodiments of the present invention also provide media corresponding to the above methods.

[0135] Some embodiments of the present invention provide a storage medium storing computer-executable instructions, which are executed by a processor to implement the steps of the various embodiments described above.

[0136] The various embodiments in this invention are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the device and medium embodiments are relatively simple in description because they are fundamentally similar to the method embodiments; relevant parts can be referred to the descriptions in the method embodiments.

[0137] The devices, media, and methods provided in the embodiments of the present invention are one-to-one correspondences. Therefore, the devices and media also have similar beneficial technical effects as their corresponding methods. Since the beneficial technical effects of the methods have been described in detail above, the beneficial technical effects of the devices and media will not be repeated here.

[0138] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process method or product that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process method or product. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process method or product that includes that element.

[0139] The above are merely embodiments of the present invention and are not intended to limit the invention. Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for regulating the energy flux density distribution of a concentrated solar furnace installation, characterized in that, include: Construct an optical system model for a concentrating solar furnace device; Based on the optical system model, the energy flux density distribution control model is determined according to the cross offset parameter within the light focal point of the reactor, the position parameter of the heat absorption platform where the reactor is located, and the curvature parameter of the condenser lens. Based on the energy flux density distribution control model, the control parameters of the concentrating solar furnace device are determined according to the set target area size, the peak energy flux control range within the target area, and the range of non-uniformity factors of energy flux distribution within the target area, combined with the direct normal irradiance (DNI) parameter; the target area is the area to be focused by the preset reflected light. The operating status of the corresponding components of the concentrating solar furnace device is adjusted according to the control parameters. The construction of the optical system model for the concentrating solar furnace device specifically includes: establishing a solar model, a heliostat reflection model, a concentrator focusing model, and a reactor surface receiving model in a global coordinate system; establishing a reactor surface energy flux density distribution calculation model in a local coordinate system; and constructing the optical system model of the concentrating solar furnace device based on the solar model, the heliostat reflection model, the concentrator focusing model, the reactor surface receiving model, and the reactor surface energy flux density distribution calculation model. Based on the energy flux density distribution control model, and according to the set target region size, the peak energy flux control range within the target region, and the range of non-uniformity factors of energy flux distribution within the target region, the control parameters of the concentrating solar furnace device are determined in conjunction with the direct normal irradiance (DNI) parameter. This includes: combining the energy flux density distribution control model with a genetic algorithm for parameter optimization, with the objective function... The optimization objective is to minimize the value, and the optimization solution is used to solve for the system regulation parameters; among them, in the genetic algorithm, the individual The fitness function is: ； In the formula: For fitness, Individuals within a population The corresponding non-uniformity factor of energy flux density distribution within the target region, It is the maximum estimated value of the objective function; the control parameters corresponding to the optimal fitness are determined based on the different attributes of the DNI parameters. The step of determining the control parameter corresponding to the optimal fitness based on different attributes of the DNI parameter specifically includes: when the DNI parameter is a constant, determining the control parameter corresponding to the minimum non-uniformity factor; when the DNI parameter is a variable, determining the control parameter that meets the non-uniformity factor range constraint and has the optimal fitness.

2. The method of claim 1, wherein, The optical system model for constructing a concentrating solar furnace device also includes: A global coordinate system is established with the vertex of the second condenser as the origin , , , ​ wherein the axis points to the true north, the axis points to the focal point of the condenser, the axis points to the zenith; Based on the north-south orientation of the concentrating solar furnace, the coordinates of the center point of the heliostat in the global coordinate system are represented as (0, 0, 1). ,0), where The origin of the global coordinate system and the center point of the heliostat are at... The distance on the axis; the coordinates of the center point of the heat absorption platform are represented as (0, ...). ,0), The origin of the global coordinate system and the center point of the heat absorption platform are at... Distance on the axis; With the center point of the heat absorption platform (0, Establish a local coordinate system with 0 as the origin ( , ),in and Same direction, and Same direction.

3. The method of claim 1, wherein, The focusing lens in the focusing lens model is a four-quadrant adjustable focusing secondary focusing lens; the heliostat in the reflection model is a primary heliostat, used to reflect the solar beam emitted from the solar model. Establishing a focusing model for a condenser lens specifically includes: The sunlight emitted through the solar model is reflected by a heliostat and reaches a secondary concentrator. The parallel light reflected from the primary heliostat is converged by secondary condensers in each quadrant; the direction vector of the light rays after reflection by the secondary condensers is determined according to the law of specular reflection; and the focusing model of the secondary condensers in each quadrant is determined according to the direction vector.

4. The method of claim 1, wherein, The energy flux density distribution control model, determined based on the cross-offset parameters within the light focal point of the reactor, the position parameters of the heat absorption platform where the reactor is located, and the curvature parameters of the condenser mirror, specifically includes: The position parameters of the heat-absorbing platform, the cross offset parameters within the focal point of the reactor, and the curvature parameters of the condenser mirror in the optical system model of the concentrating solar furnace device are optimized. The optimized energy flux density distribution control model is expressed as follows: ； ； ； In the formula: The control variable matrix for a concentrating solar furnace device; For the heat absorption platform along the global coordinate system Displacement variable matrix in direction, ; This is the inner cross offset matrix in the local coordinate system for the convergence of secondary condenser lenses in each quadrant, improved by a secondary condenser lens focal point offset strategy. In this context, the inner cross offset / inner cross refers to the equal inner cross offset of the focal points corresponding to the four quadrants of the secondary condenser lens from the center point of the heat absorption platform in the directions of 45°, 135°, 225° and 315°, respectively. This represents the distance, also known as the distance / focal point inner cross offset parameter; This is a curvature variable matrix for changing the curvature of the secondary condenser mirror in each quadrant via a turntable support. , The non-uniformity factor of the energy flux density distribution within the target region is used as the objective function; The number of grid cells whose center point is within the target region is called the target grid cell i. For target mesh cells The energy flux density value, in units of ; To regulate the average energy flux density within the target area, the unit is... ; The peak energy flow within the target area; and The set peak energy flow control range.

5. The method of claim 1, wherein, The parameter optimization is performed on the energy flow density distribution regulation model in combination with a genetic algorithm, with a target function The optimization of the system regulation parameters is performed with the minimum value of the target function as the optimization goal, and specifically includes: The parameters of the energy flux density distribution control model are updated based on the optimal control parameters to obtain the updated parameter solution set, and the current corresponding update number is obtained. The update includes at least crossover operation, mutation operation and selection operation. The first device control parameter is determined based on the current update count, and the first energy flow density distribution is calculated based on the current update count and the first device control parameter. The corresponding target displacement vector is determined based on the first energy flow density distribution. The target displacement vector is superimposed on the first device control parameters to recalculate the second energy flow density distribution, and the corresponding second device control parameters are determined based on the second energy flow density distribution. The second device control parameter is used as the first device control parameter for the new iteration.

6. An apparatus for regulating the flux density distribution of a concentrated solar furnace device as claimed in claim 1, characterized in that, include: The optical system model building module is used to build the optical system model of the concentrating solar furnace device; The control model construction module is used to determine the energy flux density distribution control model based on the optical system model, according to the cross offset parameter within the light focal point of the reactor, the position parameter of the heat absorption platform where the reactor is located, and the curvature parameter of the condenser lens. The control parameter calculation module is used to determine the control parameters of the concentrating solar furnace device based on the energy flux density distribution control model, according to the set target area size, the peak energy flux control range within the target area, and the range of non-uniformity factors of energy flux distribution within the target area, combined with the direct normal irradiance (DNI) parameter; the target area is the area to be focused by the preset reflected light. The control module is used to control the working status of corresponding components of the concentrating solar furnace device according to the control parameters.

7. An apparatus for applying a flux density distribution regulation method to a concentrated solar furnace installation, characterized in that it comprises: include: At least one processor; as well as, The memory is communicatively connected to the at least one processor via a bus; wherein, The memory stores instructions executable by the at least one processor, which are executed to implement the method as described in any one of claims 1-5.

Images