Generalized compound parabolic condenser based on reflection light cone matching and design method thereof

Abstract

The invention discloses a generalized compound parabolic condenser based on reflection light cone matching and a design method thereof, and belongs to the technical field of solar photo-thermal utilization. The device comprises a receiving body, a main reflecting mirror located below the receiving body and an auxiliary reflecting mirror located at the bottom of the receiving body. Under the condition of a given receiving half angle, independent geometric control parameters are introduced, rigid constraints of the height and the receiving half angle of a traditional condenser are relieved, and a group of generalized main reflector molded lines enabling edge light rays deviating from the optical axis at the maximum angle to be tangent to the top of a receiver are constructed. By means of the design, the receiving aperture and the geometric condensation ratio of the system can be remarkably improved under the limited structure height, and nondestructive recycling of light of a blind area at the bottom is achieved through the auxiliary reflector based on the macro focus principle. The invention not only solves the problem of compact integration of a high-power condensation system, but also effectively improves the energy flow distribution uniformity on the surface of the receiver, relieves the local hot spot risk, and is suitable for a high-precision tracking type solar condensation system.

Description

Technical Field

[0001] This invention relates to a generalized composite parabolic concentrator based on reflective light cone matching and its design method, belonging to the field of non-imaging optical concentrator technology. Background Technology

[0002] Compound parabolic concentrators (CPCs) are a typical type of non-imaging line focusing concentrator structure. Their design is typically based on the principle of edge rays, generating the mirror profile through a geometric envelope under given receiver half-angle and receiver geometry. Due to their ability to achieve the theoretically maximum concentration ratio, CPCs hold a crucial position in the field of solar thermal utilization. CPCs have become a core component of low-temperature solar thermal collectors and photovoltaic / photothermal coupling systems.

[0003] However, in practical engineering applications, the traditional CPC structure faces serious challenges:

[0004] Lack of design freedom: Under the condition of a circular tubular receiver, the reflector profile of a traditional CPC is uniquely locked by two parameters: the "receiving half-angle" and the "receiving body size". Designers cannot adjust the aspect ratio of the reflector according to engineering requirements (such as wind load resistance and installation space limitations), resulting in rigid structural design.

[0005] The contradiction between structural height and concentration ratio: In the case of tracking with a small receiving half-angle, the height of traditional CPC increases exponentially, resulting in a bulky system and huge wind resistance; while in the case of fixed with a large receiving half-angle, traditional CPC is often too deep, making it difficult to achieve flat integration with the building roof.

[0006] Performance loss due to simple truncation: Existing technologies often use truncation to reduce height, which directly leads to a significant reduction in the effective receiving aperture, and the actual light-gathering capacity of the system is far lower than the theoretical design value.

[0007] Existing improvement schemes typically fail to address the underlying logic of "spatial matching between the reflected light cone and the receiver," lacking a universal design paradigm that can maintain a high interception rate while flexibly adjusting the geometry. For example, some studies have optimized light distribution by introducing secondary mirrors or non-imaging surfaces, but these still do not break through the geometric constraints of traditional CPCs and cannot fundamentally resolve the contradiction between structural compactness and optical performance. Summary of the Invention

[0008] The purpose of this invention is to propose a generalized composite parabolic concentrator based on reflected light cone matching and its design method. By introducing independent geometric control parameters, a family of generalized composite parabolic profiles that satisfy the reflected light cone matching conditions are constructed. This breaks the rigid constraints of traditional concentrator height and receiving half-angle, significantly improving the system's receiving aperture and geometric concentration ratio within a limited structural height. Furthermore, auxiliary mirrors are used to achieve lossless recovery of light from the bottom blind zone, thereby solving the problems of compact integration and thermal safety in high-concentration systems.

[0009] The generalized composite parabolic concentrator based on reflected light cone matching described in this invention includes: The receiver has a predetermined cross-sectional shape; A primary reflector is disposed in the peripheral area of ​​the receiver, and the primary reflector is a non-imaging reflector. Given a receiving half-angle, the profile of the primary reflector is determined by an edge ray matching rule and an independent geometric control parameter. The edge ray matching rule is configured such that the edge ray with the largest deviation angle from the optical axis in the reflected light cone corresponding to any reflection point on the main reflector forms a predetermined geometric relationship with the predetermined area of ​​the receiver after one reflection. The geometric control parameters are used to adjust the starting position or geometric dimensions of the primary reflector, thereby forming a variety of reflector configurations that satisfy the edge ray matching rules; The profile of the primary reflector is a continuous trajectory generated based on an equal optical path structure, and its geometry is determined by the geometric control parameters.

[0010] The geometric control parameters are integration constants or equivalent initial tangent length parameters used to determine the profile of the primary reflector. These parameters are applied given the receiver radius r and the receiver half-angle θ. a Under certain conditions, the contour trajectory of the primary mirror is uniquely determined. Its value can be obtained through analytical calculation, numerical iteration, or ray tracing, and different values ​​result in different mirror geometries.

[0011] Unlike traditional designs, this invention releases the basic tangent length (or initial phase angle) as an independent geometric shape control parameter. Therefore, the profile of the primary reflector constitutes a family of generalized composite parabolic profiles that satisfy the aforementioned matching rules. The traditional narrow-sense CPC is merely a special case (degenerate form) when this parameter takes a specific value. By adjusting this parameter, the aspect ratio of the primary reflector can be flexibly controlled without changing the receiving half-angle, achieving effective utilization of the unused space at the bottom of the receiver.

[0012] Furthermore, this invention achieves a unified optical design principle for the primary and auxiliary mirrors. Both the primary and auxiliary mirrors are geometrically based on the generalized macro-focal curve, constructed using Fermat's principle (equal optical path principle) or the tethered method. Specifically, the primary mirror corresponds to a first-type macro-focal curve segment with the receiver as the real focus and infinity (or a specific edge ray direction) as the virtual focus; while the auxiliary mirror corresponds to a second-type macro-focal curve segment with the receiver as the real focus and a specific point on the edge of the primary mirror as the virtual focus. Through geometric control parameters, the optical path and boundary conditions are smoothly connected, together forming a closed optical capture system.

[0013] Preferably, the predetermined geometric relationship is as follows: the edge ray with the largest deviation angle from the optical axis in the reflected light cone is tangent to the light-facing surface of the receiver after one reflection.

[0014] Preferably, it also includes an auxiliary reflector, disposed between the bottom region of the receiver and the bottom end of the main reflector; The auxiliary reflector is used to compensate for the optical blind zone formed in the bottom region due to the outward expansion of the main reflector under the adjustment of geometric control parameters, and to guide the light that the main reflector cannot directly project onto the receiver to the receiver.

[0015] Preferably, the contour construction of the auxiliary reflector is associated with the geometric control parameter values ​​of the primary reflector, so as to adapt to the reflection area formed by the primary reflector under the adjustment of the geometric control parameters, where the edge rays no longer directly meet the reachability conditions of the receiver; Preferably, the auxiliary reflector is generated based on the generalized edge ray principle or equal optical path construction method consistent with the main reflector. Its outline is formed by splicing segmented macrofocal curves with specific points on the outline of the main reflector as virtual focal points, which is used to realize the optical path closure of the light in the region.

[0016] Preferably, the profile of the primary reflector is a family of continuous curves that satisfy the reflection cone matching condition, wherein different curves correspond to different values ​​of geometric control parameters; when the geometric control parameters take specific values, the profile of the primary reflector degenerates into the reflector profile of a traditional composite parabolic concentrator (CPC).

[0017] Preferably, the geometric control parameters corresponding to the profile of the primary reflector are configured to keep the height and material usage of the primary reflector within a predetermined range.

[0018] Preferably, the range of the receiving half-angle covers 0.1° to 90°.

[0019] Preferably, the cross-section of the receiver is circular, approximately circular, or tubular; the main reflector is disposed below or to the side of the receiver.

[0020] The design method of the generalized composite parabolic concentrator based on reflected light cone matching described in this invention includes: Determine the parameters of the receiver and the system's receiving half-angle; Select independent geometric shape control parameters; Based on the predetermined geometric relationship between the reflected light cone and the receiver, and combined with the geometric shape control parameters, the profile of the primary reflector is generated. The profile of the primary reflector constitutes a family of generalized composite parabolic profiles that satisfy the above-mentioned predetermined geometric relationship.

[0021] Preferably, the generation of the main reflector profile is achieved through one or more of analytical calculation, numerical calculation, or ray tracing.

[0022] Compared with existing technologies, the generalized composite parabolic concentrator and its design method based on reflected light cone matching of the present invention exhibit the following beneficial effects in terms of technical performance and practical applications: (1) Breaking through the limitations of engineering height to achieve a leap in light-gathering performance This invention breaks through the geometric constraint that the traditional CPC profile is uniquely locked by the "receiving half-angle". Under given engineering height constraints (such as the wind load resistance limit of the tracking system), by adjusting the geometric control parameters to drive the main reflector to expand outward, the idle space at the bottom of the receiver can be fully utilized, enabling a leapfrog improvement in the system's effective receiving aperture and geometric focusing ratio (simulations show an improvement of more than 3 times). This solves the problem of the significant reduction in focusing ability caused by the forced truncation of traditional CPC.

[0023] (2) Extremely compact design reduces system wind load and cost While achieving the same focusing ratio, the generalized linear structure of this invention can reduce the mirror height by an order of magnitude (e.g., more than 90%) compared to the traditional CPC. This extreme compactness significantly reduces the center of gravity height, material consumption, and windward area of ​​the focusing system, thereby greatly reducing the driving energy consumption of the tracking device and the cost of the support structure, making it possible to use CPC for large-scale engineering applications of high-magnification linear focusing technology.

[0024] (3) Lossless closed-loop optical path, eliminating geometric optical dead zone This invention proposes a synergistic mechanism of "primary mirror edge ray clipping" and "bottom auxiliary mirror macro-focus blind spot filling." The primary mirror is responsible for maximizing light capture, while the auxiliary mirror, through segmented construction of "moving focus" and "fixed focus," precisely blocks the bottom optical blind spot caused by the outward expansion of the primary mirror. This design avoids the energy loss caused by aperture shrinkage in traditional truncated CPC designs and solves the light leakage problem associated with the decoupling of non-imaging optical parameters, achieving theoretically full-ray interception.

[0025] (4) Optimize energy flow distribution and improve thermal safety Thanks to the wide aperture of the generalized primary reflector and the optimized optical path of the auxiliary reflector, this invention significantly reduces the average incident angle of light reaching the receiver surface, thereby reducing Fresnel reflection losses on the glass wall of the vacuum tube. Simultaneously, this structure effectively improves the circumferential energy flux density distribution of the receiver, eliminates the risk of localized hot spots commonly found at the bottom of traditional CPC systems, and significantly enhances the operational safety and service life of the heat collection system. Attached Figure Description

[0026] Figure 1 : A schematic diagram of the overall structure of the generalized composite parabolic concentrator of this invention; Figure 2 : A schematic diagram of the principle of reflected light cone matching in this invention; Figure 3 : Schematic diagram of the main reflector profile family under different geometric control parameters of the present invention; Figure 4 This invention utilizes a bottom auxiliary reflector based on the principle of edge rays to construct an optical path. Figure 5 : Schematic diagram of the application of the concentrator of this invention in tracking concentrating conditions; Figure 6 : A schematic diagram illustrating the geometric relationship and parameter definition of an exemplary reflector of the present invention; Figure 7 : A schematic comparison diagram of the reflected light of the present invention covering the receiver circumferentially; In the figure, (a) is a partial coverage effect diagram of a traditional narrow receiving angle concentrator, and (b) is a diagram of the better circumferential coverage effect achieved by the generalized concentrator of the present invention. Figure 8 Comparison of the optical paths of the generalized concentrator of this invention and the traditional truncated concentrator under the same height constraint; In the figure, (a) is the optical path diagram of the generalized concentrator of the present invention; (b) is the optical path diagram of the conventional cut-off concentrator. Figure 9 The flowchart of the design method of the generalized composite parabolic concentrator based on reflected light cone matching of this invention; In the diagram: 1. Receiver; 2. Primary reflector; 3. Auxiliary reflector. Detailed Implementation

[0027] 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. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0028] Example 1: Basic principle description: like Figures 1-2 As shown, the generalized composite parabolic concentrator based on reflected light cone matching of the present invention includes: a receiver 1; and a main reflector 2 disposed in the peripheral area of ​​the receiver 1, wherein the main reflector 2 is a non-imaging reflector. Under a given receiving half-angle condition, the profile of the primary reflector 2 is determined by introducing independent geometric control parameters, so that the far-axis edge light rays in the reflected light cone corresponding to the reflection point on the primary reflector 2 form a predetermined geometric relationship with the predetermined area of ​​the receiver 1 after one reflection. Among them, the profile of the primary reflector 2 constitutes a family of generalized composite parabolic profiles that satisfy the above-mentioned predetermined geometric relationships.

[0029] In this embodiment, the receiver 1 is a circular tube, and the main reflector is located below the receiver 1.

[0030] The contour construction of the primary reflector 2 follows a principle combining "edge ray matching rules" and "independent geometric parameter control." Specifically, this rule requires that the edge ray (i.e., the one with the largest angle of deviation from the optical axis) in the light cone reflected from any point on the primary reflector 2 (i.e., the edge ray) must be the one whose angle of deviation from the optical axis is the largest. Figure 2 Ray2r in the image is tangent to the upper region of the light-facing side of receiver 1 after one reflection.

[0031] Unlike traditional designs, this embodiment introduces a feature independent of the receiving half-angle θ. a The geometric shape control parameters, excluding the receiver radius *r*, can be mathematically described as the initial base tangent length or the distance between the starting points and the center. By adjusting these parameters, a family of generalized profiles with different aspect ratios and aperture sizes can be generated without changing the optical receiving angle. This allows designers to actively balance "structural height constraints" with "receiving aperture size."

[0032] like Figure 3 As shown, with the geometric dimensions and receiving half-angle of receiver 1 remaining unchanged, the present invention can generate a family of generalized profiles that satisfy the above-mentioned far-axis edge ray Ray2r tangent conditions by introducing independent geometric shape control parameters (such as the basic tangent length Lconst).

[0033] Figure 3 The image shows three different curves: Outer dashed line: corresponds to a larger parameter value, close to the traditional narrow definition of CPC, with a high concentration ratio but a bulky structure; Inner solid line: Corresponds to smaller parameter values, which significantly reduces the height of the reflector and achieves an extremely compact structure, making it suitable for scenarios with high wind resistance requirements.

[0034] Through this parametric design, the present invention provides engineering applications with the freedom to flexibly balance between "concentration efficiency" and "structural size".

[0035] To further illustrate a feasible way of constructing the profile of the primary mirror while satisfying the geometric constraint that "the far-axis edge ray (Ray2r) is tangent to the light-facing surface of the receiver", an exemplary geometric description is given below.

[0036] It should be noted that the profile of the primary reflector in this invention is, in essence, a macro-focal curve in geometric optics. It is constructed according to the basic principle of the string method, that is, for any point on the primary reflector, the wavefront of the ray from it to the incident edge (perpendicular to the incident direction θ) is... a The optical path length of the involute curve (CPC) remains constant, as does the sum of the optical path length at that point, through the tangent point on the receiver surface, and wound to a specific reference point on the receiver. Within this framework, the traditional CPC is merely a special case of this family of macrofocal curves when the rope length (i.e., the optical path constant) takes a specific value determined by the complete unfolding of the involute.

[0037] The core of this invention lies in the introduction of geometric shape control parameters, which changes the initial rope length condition in the above-mentioned rope system structure (i.e., changes the optical path integral constant), thereby forming a family of "generalized line families" with different aspect ratios.

[0038] In one embodiment, the primary reflector can be described by the following trajectory equation. To further illustrate the analytical construction of the primary reflector profile, in conjunction with... Figure 6 The polar coordinate system shown is defined with the center of the receiver circle as the origin and the opposite direction of the optical axis as the polar axis. θ in the diagram... a Let r be the half-angle of the system reception, and r be the equivalent radius of the receiver. The polar angle of the reflection point is represented by ρ, the instantaneous tangent length is represented by PT, and d is the distance from the reflection point to the center of the absorber (d 2 =ρ 2 +r 2 In this coordinate system, an auxiliary constant C is introduced (as a geometric control parameter) to characterize the matching state between the reflected light cone and the receiver:

[0039] The corresponding parametric equation for the mirror profile can be expressed as:

[0040] Where the parameter is angle The range of values ​​for is:

[0041] It should be noted that the parameter C (generalized fundamental chord length parameter) in the above formula has a clear geometric and physical meaning. It corresponds to a specific initial optical path component in the optical path design.

[0042] In the traditional standard CPC construction theory, this parameter is usually fixed to a specific value Cstd (e.g., Cstd = 2r(π / 2 + θ)). a This is determined by the involute unfolding length. The key difference between this invention and existing technologies is that this invention releases parameter C as an independent design variable.

[0043] Parameter adjustment mechanism: By adjusting the value of the auxiliary constant C, a family of mirror profiles with different aspect ratios can be generated, provided that the receiving half-angle constraint is satisfied (e.g., ...). Figure 3 (As shown).

[0044] (1) Compact convergent type (corresponding to smaller parameter values): The profile of the main reflector is contracted inward, which significantly reduces the height of the reflector. It is suitable for scenarios that are extremely sensitive to wind resistance loads and do not have high requirements for light concentration ratio.

[0045] (2) Expanded Enhanced Type (corresponding to larger parameter values): The profile of the primary reflector expands outward, utilizing the unused space at the bottom of the receiver. Under given engineering installation height constraints, this configuration can achieve a larger receiving aperture than the conventional CPC, thereby significantly improving the geometric focusing ratio. This is the preferred form recommended by the present invention in high-precision tracking systems.

[0046] Example 2: A piecewise macro-focus curve construction strategy based on the worst-case scenario principle: To address the non-uniform light leakage area at the bottom of the generalized primary reflector due to its outward expansion design, this embodiment employs a segmented construction strategy to generate the auxiliary reflector 3. For example... Figure 4 As shown, the construction process fully considers the geometric occlusion effect of the receiver 1 on the light, and specifically uses the key geometric feature points on the main reflector (such as the light leakage critical point P0 and the edge endpoint PE) as virtual focal points to generate the trajectory.

[0047] 1. Determining the starting point: First, determine the positions of the primary reflector's edge terminal PE and the light leakage threshold P0 relative to the lowest point of the receiver. If the primary reflector extends too far (e.g., in a high-concentration configuration), causing both PE and P0 to be higher than the bottom of the receiver, then set the starting point Q1 of the auxiliary reflector as the intersection of the backward extension of the paraxial edge ray from point P0 and the Y-axis. This results in the auxiliary reflector having a "V" shape or a pointed bottom structure to penetrate the blind zone and capture light.

[0048] 2. Segmented trajectory generation: The profile of the auxiliary mirror is formed by smoothly splicing two curves that satisfy the principle of constant optical path (string method), and its corresponding virtual focal point evolves with position (see...). Figure 4 (Illustration of the optical path in the diagram) Phase 1 (Moving Focus Segment): Corresponding to Figure 4 Ray B is in the blind transition section at the beginning of the auxiliary mirror. Due to the obstruction of the receiver, the edge of the primary mirror is not visible. At this time, a "moving focus" strategy is adopted, that is, the virtual focus slides outward from the critical point P0 along the contour of the primary mirror. A transition trajectory that adapts to the change in the line of sight in the blind zone is generated using the rope method.

[0049] Second stage (focus segment): Corresponding to Figure 4 Light ray A. When the auxiliary mirror extends until the line of sight passes over the receiver's obstruction, the virtual focus is locked onto the physical terminal P of the primary mirror. E Using this as a fixed focal point, construct a macrofocal curve until the edge of the auxiliary mirror and the boundary of the primary mirror's light cone close together.

[0050] Through the above construction, the auxiliary reflector 3 can theoretically achieve lossless recovery of light from the bottom blind zone.

[0051] Example 3: High-performance tracking focusing applications (ultimate optimized version): This embodiment demonstrates the invention's application at small receiving angles (such as θ). a The application value of a high-concentration photovoltaic system (=0.5°). To simulate the need for low-profile installation in areas with strong winds, we strictly limited the system installation height to 0.24% of the total height according to the classic CPC theory.

[0052] 1. Comparison of geometric configuration and light-gathering performance (based on...) Figure 8 ); Under these stringent height restrictions, such as Figure 8 As shown in (b), the traditional CPC is forced to undergo a significant truncation, resulting in a severe contraction of its receiving aperture and a geometric concentration ratio of only about 10.7.

[0053] In comparison, such as Figure 8As shown in (a), the generalized concentrator of this invention drives the primary reflector to expand significantly outward by adjusting geometric control parameters. A comparison shows that, at the same height, the receiving aperture of this invention is significantly wider than that of the conventional structure. Simultaneously, the bottom blind zone created by the outward expansion of the primary reflector is precisely sealed by the "V"-shaped auxiliary reflector, ensuring that all edge light rays are converged to the receiver without optical leakage.

[0054] Simulation results show that the geometric focusing ratio of this structure at the same height is increased to 44.1, an improvement of up to 310%. Considering the actual working condition of specular reflectivity (ρ=0.94), the effective optical focusing ratio of this invention is still as high as 41.26, far exceeding the 10.11 of the traditional structure.

[0055] 2. Ray convergence in tracking mode (based on) Figure 5 ); like Figure 5 As shown, this embodiment further demonstrates the light-gathering state of the concentrator during dynamic tracking. Thanks to the wide aperture characteristics of the primary mirror and the cooperation of the auxiliary mirror, even at an extremely small receiving angle of 0.5°, the incident light can still be efficiently collected and focused onto the receiver, verifying its optical stability in the tracking system.

[0056] 3. Energy flow distribution and thermal safety (based on) Figure 7 ); like Figure 7 As shown, the light coverage effects of the two structures are compared. Figure 7 Image (a) shows that the light from a traditional narrow-aperture concentrator is mainly concentrated at the bottom of the receiver, which easily forms localized hot spots and threatens operational safety. Figure 7 As shown in Figure (b), thanks to the wide-angle reflected light path of this invention, the light coverage around the receiver exhibits a uniform bimodal distribution, effectively eliminating the risk of localized high energy flux density at the bottom. This not only improves power generation / heat collection efficiency but also significantly extends the service life of the receiver.

[0057] Example 4: Design Methodology: like Figure 9 As shown, this embodiment provides a design method for a generalized composite parabolic concentrator based on reflected light cone matching. The specific steps are as follows: Determine basic parameters: Based on the application requirements of the focusing system, determine the cross-sectional shape of receiver 1, with a diameter equal to the half-angle of the system's receiving angle.

[0058] Select control parameters: Select the height of the primary reflector 2 as the geometric control parameter.

[0059] Generating the profile of the primary reflector: Based on the geometric relationship that the far-axis edge rays are tangent to the light-facing surface of receiver 1, the profile equation of the primary reflector 2 is solved using analytical calculation, numerical calculation, or ray tracing. Through iterative calculation, a generalized composite parabolic profile that meets the height requirements is obtained. The primary reflector 2 corresponding to this profile can effectively reflect light within the receiving half-angle range to receiver 1.

[0060] Auxiliary reflector design: Based on the contour of the main reflector 2, it is determined that there is a risk of light leakage between its bottom end and the bottom area of ​​the receiver 1. Therefore, an auxiliary reflector 3 is designed. Taking the bottom end of the main reflector 2 as the virtual focal point, the contour of the auxiliary reflector 3 is constructed based on the principle of edge rays to ensure that the light from the leakage area is captured by the receiver 1 after being reflected by the auxiliary reflector 3.

[0061] This embodiment achieves extreme compactness of the concentrator while ensuring high performance through parametric design and optical optimization, providing a cost-effective concentrating solution for quasi-static distributed photovoltaic systems.

[0062] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A generalized composite parabolic concentrator based on reflected light cone matching, characterized in that, include: The receiver (1) has a predetermined cross-sectional shape; The main reflector (2) is disposed in the peripheral area of ​​the receiver (1), and the main reflector (2) is a non-imaging reflector; Under a given receiving half-angle condition, the profile of the primary reflector (2) is determined by the edge ray matching rule and an independent geometric control parameter. The edge ray matching rule is configured such that the edge ray with the largest deviation angle from the optical axis in the reflected light cone corresponding to any reflection point on the main reflector (2) forms a predetermined geometric relationship with the predetermined area of ​​the receiver (1) after one reflection. The geometric control parameters are used to adjust the starting position or geometric scale of the primary reflector (2), thereby forming a variety of reflector configurations that satisfy the edge ray matching rules; The outline of the primary reflector (2) is a continuous trajectory generated based on the equal optical path structure, and its geometry is determined by the geometric control parameters.

2. The generalized composite parabolic concentrator based on reflected light cone matching according to claim 1, characterized in that: The predetermined geometric relationship is as follows: after one reflection, the far-axis edge light rays in the reflected light cone form a tangential relationship with the light-facing side surface of the receiver (1).

3. The generalized composite parabolic concentrator based on reflected light cone matching according to claim 1, characterized in that: It also includes an auxiliary reflector (3), which is disposed between the bottom region of the receiver (1) and the bottom end of the main reflector (2); The auxiliary reflector (3) is used to compensate for the optical blind zone formed in the bottom region due to the outward expansion of the main reflector (2) under the adjustment of geometric control parameters, and to guide the light that the main reflector (2) cannot directly project onto the receiver (1) to the receiver (1).

4. The generalized composite parabolic concentrator based on reflected light cone matching according to claim 3, characterized in that: The contour construction of the auxiliary reflector (3) is related to the geometric control parameter values ​​of the main reflector (2) to adapt to the reflection area formed by the main reflector (2) under the adjustment of the geometric control parameters, where the edge rays no longer directly meet the reachability conditions of the receiver; The auxiliary reflector (3) is generated based on the generalized edge ray principle or equal optical path construction method consistent with the main reflector (2). Its outline is formed by splicing segmented macrofocal curves with specific points on the outline of the main reflector (2) as virtual focal points, and is used to realize the optical path closure of the light in the region.

5. The generalized composite parabolic concentrator based on reflected light cone matching according to claim 1, characterized in that: The profile of the primary reflector (2) is a family of continuous curves that satisfy the matching condition of the reflected light cone, wherein different curves correspond to different values ​​of geometric control parameters; when the geometric control parameters take a specific value, the profile of the primary reflector (2) degenerates into the reflector profile of a traditional composite parabolic concentrator (CPC).

6. The generalized composite parabolic concentrator based on reflected light cone matching according to claim 1 or 5, characterized in that: The geometric control parameters corresponding to the profile of the primary reflector (2) are configured to keep the height and material usage of the primary reflector (2) within a predetermined range.

7. The generalized composite parabolic concentrator based on reflected light cone matching according to claim 1, characterized in that: The range of the receiving half-angle is from 0.1° to 90°.

8. The generalized composite parabolic concentrator based on reflected light cone matching according to claim 1, characterized in that: The receiver (1) has a circular, approximately circular or tubular cross-section; the main reflector (2) is located below or to the side of the receiver (1).

9. A design method for a generalized composite parabolic concentrator based on reflected light cone matching as described in any one of claims 1-8, characterized in that, include: Determine the parameters of receiver (1) and the system receiving half-angle; Select independent geometric shape control parameters; Based on the predetermined geometric relationship between the reflected light cone and the receiver (1), and combined with the geometric shape control parameters, the outline of the main reflector (2) is generated. The outline of the main reflector (2) constitutes a family of generalized composite parabolic profiles that satisfy the above-mentioned predetermined geometric relationship.

10. The design method of the generalized composite parabolic concentrator based on reflected light cone matching according to claim 9, characterized in that: The profile of the primary reflector (2) is generated by one or more of the following methods: analytical calculation, numerical calculation, or ray tracing.

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