WO2015044359A1

WO2015044359A1 - Attachment of a secondary optic on a photovoltaic receiver

Info

Publication number: WO2015044359A1
Application number: PCT/EP2014/070636
Authority: WO
Inventors: Jean- Edouard DE SALINS
Original assignee: Heliotrop
Priority date: 2013-09-27
Filing date: 2014-09-26
Publication date: 2015-04-02
Also published as: FR3011387B1; FR3011387A1

Abstract

The invention relates to an assembly (1) comprising: - a photovoltaic receiver (2) on which is attached a photovoltaic cell (22), - a secondary optic (3), and - a support (4) suitable for positioning and attaching the secondary optic (3) in relation to the photovoltaic cell (22), comprising guide means (52, 38), configured for adding and centring the secondary optic (3) in the space with respect to the cell (22), and means of fixation (46), forming a stop for the secondary optic (3) and configured to lock the secondary optic (3) in an operating position with respect to the cell (22).

Description

Attaching a secondary optic to a

photovoltaic receiver

FIELD OF THE INVENTION

The invention relates to solar photovoltaic concentration technology, and more specifically assemblies comprising an electronic receiver equipped with a photovoltaic cell and surmounted by an optical component for concentrating the light on the cell adapted for use in modules with photovoltaic concentration. , and an associated manufacturing method.

BACKGROUND

A photovoltaic receiver comprises a substrate on which electronic components are fixed, in particular a photovoltaic cell adapted to generate an electric current when exposed to light transmitted by a light concentration system, for example a Fresnel lens. The photovoltaic receiver is itself fixed on a heat sink having a high thermal conductivity.

Many photovoltaic receivers are assembled with a secondary optics, which can be reflective or refractive, in order to improve the concentration of light flux on the cell and to compensate for any misalignment of the focal axis of the concentration system with the sun axis and / or a positioning error of the cell with respect to the focal center of the lens. The secondary optics also makes it possible to homogenize the flow spatially and spectrally on the cell.

The positioning and fixation of the secondary optics are therefore major issues for the performance of the module are satisfactory, whether in ambient temperature or in operation. For this purpose, it is necessary that the following elements are positioned and oriented in space with precision, with a low dimensional tolerance: the input section of the secondary optics, that is to say the part of the secondary optics extending facing the lens and through which the light rays penetrate, with respect to the photovoltaic cell,

the output section of the secondary optics, that is to say the portion of the secondary optics extending opposite the photovoltaic cell and through which the light rays emerge, with respect to the photovoltaic cell, and

- the axis of the secondary optics relative to the normal of the photovoltaic cell.

In operation, the photovoltaic receiver may be subjected to a harsh environment, and in particular to temperatures exceeding 100 ° C due to the flux concentrated by the lenses (whose power density may be greater than 50 W / cm ² ), which may deform the secondary optics when it is metallic or its possible support. In particular, in the case of a secondary reflective optics, it is recommended that the temperature of the secondary optics does not exceed 180 ° C to prevent its constituent material from being degraded, and that it is even less than 100 ° C to limit the risk of component fatigue.

The attachment of the secondary optics to the photovoltaic receiver must also be carried out in such a way as to avoid excessive contact or pressure, so as not to damage the electrical contacts between the photovoltaic cell and the substrate pads, which are very sensitive. Moreover, in case of poor fixation, the fall of a secondary optics calls into question the whole module if it is not detected.

It has therefore been proposed, particularly in document US 201 1/048535, to screw the secondary optics on the receiver sink. The sink being grounded, the screwing therefore puts the secondary optics to the ground as well. However, the potential of the photovoltaic cell can rise to several thousand volts, so that the risk of arcing and breakdown are very important, given the large potential difference. Moreover, fixing the secondary optics is very expensive and time consuming to achieve, in order to avoid possible short circuits when screwing on the heatsink. Finally, its accuracy is not sufficient to ensure proper positioning of the secondary optics relative to the photovoltaic cell. Indeed, the positioning of the secondary optics depends on screwing, which is performed by an operator, and can vary from one receiver to another.

It has also been proposed in document US 2008/087323, an assembly comprising a photovoltaic receiver, a secondary optics and a support, configured to block the secondary optics relative to the receiver. For this, the support comprises U-shaped protuberances which deform elastically to block the secondary optics. However, this system of protuberances does not allow to center accurately the secondary optics relative to the receiver, since it requires to bring the secondary optics along an axis substantially perpendicular to the receiver.

Document GB 2 497 327 in turn describes an assembly comprising a photovoltaic receiver and a secondary optics, fixed with the aid of a clip. However, this type of fixation does not sufficiently stabilize the secondary optics. Moreover, the proposed clip is not adapted to fix with reflexive secondary optics.

SUMMARY OF THE INVENTION

An object of the invention is to propose a new system for attaching a secondary optic to a photovoltaic receiver, which is simple to produce at a lower cost, which is able to withstand the severe environments that can be experienced in a photovoltaic concentration module by overcoming the problems of breakdown, while improving the positioning of the secondary optics relative to the photovoltaic cell.

For this, the invention proposes an assembly comprising:

a photovoltaic receiver on which is fixed a photovoltaic cell,

- a secondary optics, and a support adapted to position and fix the secondary optics relative to the photovoltaic cell,

wherein the support comprises guide means, configured to center the secondary optics in space with respect to the photovoltaic cell, and securing means, forming a stop for the secondary optics and configured to block the secondary optics in an operating position with respect to the photovoltaic cell.

Some preferred but non-limiting characteristics of the assembly described above are the following:

the support comprises a base fixed on the photovoltaic receiver and two fins extending from the base,

the photovoltaic receiver comprises a substrate on which the photovoltaic cell and the support are fixed,

the base of the support is brazed on the substrate,

the photovoltaic receiver comprises a substrate provided with tracks, the photovoltaic cell being connected to the substrate by means of electrical contacts, and in which the base of the support comprises a peripheral edge which delimits a through opening through which the cell can be exposed; photovoltaic, said electrical contacts, and possibly a part of the substrate areas,

the photovoltaic receiver furthermore comprises an encapsulant adapted to protect the photovoltaic cell, the extension of the encapsulant on the substrate being delimited by the through opening of the base of the support,

the fastening means comprise protuberances, adapted to abut against a lower face of the secondary optics,

the lower face of the secondary optics comprises cutouts adapted to receive the protuberances of the fixing means,

the fins and the secondary optics comprise associated detent elements forming a non-return system so as to form a stop for the secondary optics, the detent elements comprise notches and resilient tongues, the notches being each adapted to receive an elastic tongue,

the guide means comprise guide grooves and associated guide ribs, formed in the fins of the support and in the secondary optics, in order to allow the sliding of the secondary optics and its progressive guidance towards its operating position by the support,

the guide grooves are formed in the fins, while the guide ribs project from the secondary optics,

- the guide ribs are formed by edges of the walls

each fin comprises central walls adapted to come into contact with side walls of the secondary optics in order to participate in the heat dissipation of the secondary optics,

the guide grooves of each fin extend on either side of the central wall,

- The support is made of an aluminum alloy, in bronze, in copper, or in a ceramic covered with a layer of copper, the finish of this layer can be made of nickel with or without gold protection, pewter or in Silver, and

the secondary optics is reflective or refractive,

According to a second aspect, the invention also proposes a support for secondary optics of an assembly as described above, said support being adapted to position and fix the secondary optics relative to a photovoltaic cell of the photovoltaic receiver, and comprising guiding means, configured to set up and center the secondary optics in the space with respect to the photovoltaic cell, and fixing means forming a stop for the secondary optics and configured to block the secondary optics in position by compared to the photovoltaic cell.

According to a third aspect, the invention also proposes secondary optics, adapted to be positioned and fixed on a receiver photovoltaic of an assembly using a support as described above.

According to a preferred but nonlimiting characteristic, the secondary optics comprises means adapted to cooperate with the guide means and the means for fixing the support.

According to a fourth aspect, the invention also proposes a photovoltaic module, comprising:

a bottom wall adapted to fix in position a series of assemblies as described above,

a front face, adapted to fix in position a series of concentration systems, and

- Side walls, connecting the bottom wall and the front face so as to define a closed box.

According to a preferred but nonlimiting characteristic, the support of the photovoltaic module is made of a conductive material, the assemblies being connected electrically in pairs in series through their support.

According to a last aspect, the invention also proposes a method of manufacturing an assembly as described above, in which the secondary optics is fixed on the receiver according to the following successive steps:

- Establishment and centering of the secondary optics in the guide means of the support, then

fixing the secondary optics in its operating position by means of the support fixing means.

Some preferred but nonlimiting features of the process are as follows:

the secondary optics is furthermore fixed by snapping into the means for fixing the support,

the photovoltaic receiver comprises a substrate on which the photovoltaic cell is fixed, and the method also comprises, prior to the steps of placing and centering and fixing the optics secondary, a step during which the support is brazed on the substrate of the photovoltaic receiver,

the support comprises a peripheral edge delimiting a through opening, and during the brazing step, the peripheral edge of the support being fixed around the photovoltaic cell so that the photovoltaic cell is opposite the opening of the base support, and

- The photovoltaic receiver further comprises an encapsulant adapted to protect the photovoltaic cell, and the method further comprising a step in which the encapsulant is applied to the photovoltaic cell and is polymerized.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features, objects and advantages of the present invention will appear better on reading the detailed description which follows, and with reference to the appended drawings given by way of non-limiting examples and in which:

FIG. 1 is a perspective view of an assembly example according to an embodiment of the invention, in which the secondary optics is in the operating position,

FIG. 2 is a perspective view of the secondary optical support of the assembly of FIG. 1,

FIG. 3 is a side view of the secondary optical support of FIG. 2,

FIG. 4 is a front view of the secondary optical support of FIG. 2,

FIG. 5 is a view from above of the secondary optical support of FIG. 2,

FIG. 6 is a detailed view of part of the secondary optical medium of FIG. 5,

FIG. 7 is a perspective view of the secondary optics of FIG. 1, FIG. 8 is a perspective view of a photovoltaic module, part of which of the side walls has been omitted in order to visualize the assemblies and the bottom wall,

FIG. 9 is a view from above of a first exemplary embodiment of a refractive secondary optics,

FIG. 10 is a side view of the refractive secondary optics,

FIG. 11 is a sectional view of an assembly example according to a second embodiment of the invention, in which the secondary optics is in the operating position, and

Figure 12 is a flowchart showing various steps of an exemplary embodiment of the method of manufacturing an assembly according to the invention.

DETAILED DESCRIPTION OF AN EMBODIMENT

In what follows, the invention will be more particularly described and illustrated in the case of a reflective secondary optics 3. This is however not limiting, insofar as the invention applies equally well for fixing and centering a refractive optic 3 '. FIG. 1 illustrates an example of assembly 1 according to a first embodiment of the invention, comprising a photovoltaic receiver 2 on which a secondary optic 3 is fixed. Such an assembly 1 is intended to be fixed by known means on a dissipator 5, then integrated in a bottom wall of a photovoltaic module 10, facing 14 light concentration systems, such as Fresnel lenses.

A photovoltaic receiver 2 comprises a substrate 20 on which electronic components are fixed, in particular a photovoltaic cell 22 adapted to generate an electric current when exposed to light transmitted by a concentration system 14. The photovoltaic cell 22 can be connected to the surfaces 21 of the substrate 20 by means of electrical contacts 23, for example several wires of connection, extending between its peripheral portion 42 (busbar) and said pads 23.

The substrate 20 may for example be made of copper, aluminum or ceramic.

The photovoltaic cell 22 is protected by means of an encapsulant

(Not visible in the figures), which extends over the photovoltaic cell 22 and at least partially covers the electrical contacts 23 or the beaches 21 of the substrate 20. The encapsulant may for example comprise silicon.

The secondary optics 3 may be reflective or refractive, and is adapted to compensate for any misalignment of the focal axis of the concentration system 14 associated with the axis of the sun and / or a positioning error of the cell 22. in relation to the focal center of this concentration system 14.

For example, FIG. 7 illustrates an embodiment of a reflective secondary optics 3 that can be used in the invention. This secondary optic 3 comprises four sidewalls 30-33 connected together at their edges to form a truncated cone. The side walls 30-33 together define an inlet section 34, through which the light rays coming from the concentration systems 14, and an output section 35, through which the light rays emerge in the direction of the photovoltaic cell 22. The facing faces of the side walls 30-33 are active surfaces adapted to concentrate the luminous flux coming from the concentration systems 14 onto the photovoltaic cell 22. Moreover, the input section 34 of the secondary optics 3 is preferably greater than its outlet section 35.

The assembly 1 further comprises a support 4, adapted to position and fix the secondary optics 3 relative to the photovoltaic cell 22. For this, the support 4 comprises guide means 52, configured to center the secondary optics 3 in space with respect to the photovoltaic cell 22, and fixing means 46 forming a stop for the secondary optics 3 and configured to block the secondary optics 3 in position relative to the photovoltaic cell 22. According to one embodiment, the support 4 may further comprise a non-return system 53, to prevent the removal of the secondary optics 3 once it has engaged in the means of fixing 46 of the support 4.

Advantageously, the guide means guide the secondary optics 3 to its operating position in the assembly 1 while preserving the integrity of the secondary optics 3, which is very fragile and whose surface flatness is critical. The fixing means 46 in turn form a Z-stop (that is to say in a normal direction to the general plane of extension of the photovoltaic cell 22), to prevent the secondary optics 3 is not disposed too close to the electrical contacts 23, which could cause a breakdown.

For this, the support 4 may in particular comprise a base 40, which can be fixed on the photovoltaic receiver 2, and two fins 50, extending from the base 40 and adapted to support the secondary optics

3. The base 40 and the fins 50 can be integrally formed in one piece. Alternatively, the fins 50 can be reported on the base

40, and / or the base 40 may be in several parts.

The fins 50 are configured to come into contact with opposite side walls 30-33 of the secondary optics 3 to guide and center them with respect to the photovoltaic cell 22.

It will of course be understood that the support 4 may also comprise a greater number of fins 50, for example four fins 50, configured to each face one of the side walls

30-33 of the secondary optics 3.

The fixing means 46 of the support 4 may in particular comprise one or more protuberances 46 adapted to form a stop for the secondary optics 3. The protuberances 46 may extend from the base 40 and / or the fins 50, and are configured to form obstacle to moving the secondary optics 3 and prevent it from getting too close to the photovoltaic cell 22.

For example, in the exemplary embodiment illustrated in FIGS. 2 to 6, the fastening means 46 comprise at least two protuberances 46 by fins 50, extending from the base 40 of the support 4 and adapted to receive a lower face ( output section 35) of the secondary optics 3.

The lower face of the secondary optics 3 can in turn comprise cutouts 36 adapted to receive the protuberances 46 when the secondary optics 3 arrive in their operating position facing the photovoltaic cell 22.

Thus, the positioning and configuration of the support 4, which is fixed on the photovoltaic receiver 2, determines the height (Z position) of the secondary optics 3 relative to the photovoltaic cell 22. The guidance means as for them can comprise guide grooves 52 and associated guide ribs 38, formed in the fins 50 of the support 4 and the secondary optics 3, to allow the sliding of the secondary optics 3 and its progressive guidance to its operating position .

Here, the guide grooves 52 are formed in the fins 50, while the guide ribs 38 project from the secondary optics 3. The fins 50 and the guide grooves 52 are then configured so that when the optics secondary 3 is inserted into the support 4, each fin 50 is in contact with one of its side walls 30-33 of the secondary optics 3, while the guide grooves 52 are engaged with guide ribs 38 associated with the secondary optics 3. The secondary optics 3 can slide along the fins 50 in the guide grooves 52, until reaching the protuberances 46 which abut and stop the secondary optics 3 in its operating position .

In the exemplary embodiment illustrated in FIGS. 2 to 6, the fins 50 extend opposite one another and each comprise two guide grooves. 52. This configuration allows the fins 50 to center the secondary optics 3 relative to the photovoltaic cell 22 and thus its positioning in X and Y (that is to say parallel to the plane of the photovoltaic cell 22).

The guide ribs 38 may be attached to the outer (passive) faces of the side walls 30-33 of the secondary optics 3, for example by gluing.

Alternatively, and as illustrated in Figures 1 and 7, the guide ribs 38 may be formed by the edges 38 of the side walls 30-33 of the secondary optics 3. For this, the side walls 30-33 can be fixed together so that two of the side walls 30, 32, said internal, extend between the two other lateral walls 31, 33, said external, secondary optics 3. The edges 38 of the outer side walls 31, 33 are therefore protruding from the surface of the inner side walls 30, 32 and forming the guide ribs 38 capable of penetrating into the associated guide grooves 52 of the fins 50.

The support 4 may further comprise a non-return system 53, 39. Such a non-return system 53, 39 may in particular comprise detent members 53, 39, adapted to cooperate with associated detent members 53, 39 of the secondary optics 3. For example, the detent members 53, 39 may comprise notches 39 and elastic tabs 53, the notches 39 being each adapted to receive a force associated elastic tongue.

Thus, in the exemplary embodiment illustrated in the appended figures, the fins 50 comprise resilient tongues 53 extending towards the secondary optics 3 and configured to cooperate with associated notches 39 formed in the secondary optics 3. More specifically, the notches 39 of the detent members are formed in the guide ribs 38 of the secondary optics 3, here the edges 38 of the lateral walls 30-33 external of the secondary optics 3, while the elastic tongues 53 are formed in the guide grooves 52 of the fins 50.

Once the tabs 53 inserted into the corresponding notches 39, they then return to their rest position by springback and prevent any movement of the secondary optics 3 relative to the support 4, and therefore with respect to the photovoltaic cell 22 .

Preferably, the tongues 53 are oriented so as to prevent the removal of the secondary optics 3 once it is engaged in the fixing means 46 of the support 4. For this, the movable part of the tongues 53 projects in the direction of the base 40 of the support 4. The tongues 53 thus also form a Z stop for the secondary optics 3.

The fins 50 may further comprise a central wall 54, extending between the guide grooves 52, adapted to come into contact with the lateral walls 30, 32 of the secondary optics 3. This central wall 54 makes it possible to improve the heat dissipation of the secondary optics 3, without adding specific polymers that could burn in case of misalignment of the assembly 1 and exposure of the polymer to the concentrated flow of the lenses.

The central wall 54 furthermore makes it possible to stabilize the secondary optics 3 in the fins 50, in particular when it is slidably fitted into the guide grooves 52. The base 40 of the support 4 can be fixed on the receiver 2 by This fixing of the support 4 on the substrate 20 is made possible by the particular structure of the support 4, which centers and fixes the secondary optics 3 not by screwing, but by means of fixing (protuberances 46) and guide means (guide grooves 52 and guide ribs 38). The support 4 is indeed less bulky, so that the fixing of the support 4 is no longer limited to the dissipator 5. Moreover, the brazing of the support 4 on the substrate 20 of the receiver 2 makes it possible to put the support 4 and the secondary optics 3 (which are therefore no longer grounded) at the same potential, and thus to avoid the problems of breakdown. due to the formation of electric arcs between the cell 22 and the secondary optics 3.

Alternatively, the base 40 of the support 4 could also be glued to the substrate 20.

Once fixed on the receiver 2, the base 40 of the support 4 extends substantially parallel to the substrate 20 on which the photovoltaic cell 22 is fixed.

The base 40 is perforated and comprises a peripheral rim 42 which delimits an opening 44 through which can be exposed the photovoltaic cell 22, and if appropriate the electrical contacts 23 and 21 of the substrate 21 beaches. of the base 40 makes it possible not to impede the light radiation that can be received by the photovoltaic cell 22, nor to prevent access to the busbar of the photovoltaic cell 22 and to the electrical contacts 23.

For this, the dimensions and the shape of the peripheral edge 42 of the base 40 are chosen in order to allow the photovoltaic cell 22, the electrical contacts 23 and the tracks 21 to be exposed through the opening 44.

Advantageously, the peripheral edge 42 of the base 40 makes it possible to contain the encapsulant prior to its fixation by polymerization on the cell 22. In fact, the encapsulant forms a sheet which tends to spread over the substrate 20 before be frozen by the polymerization step. The surface that can be covered by the encapsulant is therefore delimited by virtue of the peripheral edge 42 of the base 40. In the embodiment illustrated in FIGS. 2 to 6, the central wall 54 and the guide grooves 52 of the fins 50 are formed integrally in one piece with the base 40 of the support 4. Thus, the central wall 54 of the fins 50 extends from the base 40 of the support 4 and forms with the base 40 an angle a substantially equal to the angle between the outlet section 35 and the side wall 30, 32 of the secondary optical 3 corresponding. In this way, the central wall 54 comes into contact with the wall 30, 32 opposite the secondary optics 3 when the latter is inserted into the support 4.

In this embodiment, the protuberances 46 forming the attachment means 46 extend on either side of the central wall 54 of the fins 50, in the form of a local enlargement.

The central wall 54 is further deformed at its two lateral sides, at the right of the protuberances 46, to form the guide grooves 52. The bottom 52a of the guide grooves 52 here extends in a generally parallel plane and offset by relative to that of the central wall 54, to receive the guide ribs 38 of the secondary optics 3, which here correspond to the edges 38 of its outer side walls 31, 33.

Moreover, the walls of the guide grooves 52 intended to come into contact with the guide ribs 38 are provided with tongues 53 which project in the direction of the secondary optics 3.

In the exemplary embodiment illustrated in these figures, each guide groove 52 has a general shape of gutter successively comprising a fixing wall 52b, the bottom wall 52a and an end wall 52c. As can be seen in FIGS. 2 and 6, the elastic tongues 53 therefore extend from the end wall 52c of the grooves 52, their free end being directed towards the outlet section 35 of the secondary optics 3 when this is engaged in support 4.

The fins 50 and the base 40 may be obtained by stamping using a suitable counterfoil to form the protuberances 46, the central wall 54 and the guide grooves 52 in a single step. The tongues 53 and the through opening 44 can then be made by cutting the end wall 52c of the guide grooves 52. When the fins 50 are formed integrally with the base 40 of the support 4, the support 4 can be obtained according to the following steps:

(i) provide a sheet,

(ii) cutting the shape of the fins 50 and protuberances 46 in the sheet,

(iii) stamping the portion of the sheet for forming the fins 50 to form the central wall 54 and the guide grooves 52, and

(iv) folding the fins 50 at their junction with the base 40 so that their central wall 54 forms an angle α with the base 40 substantially equal to the angle between the outlet section 35 and the side wall 30, 32 opposite the secondary optics 3.

Preferably, the support 4 is made of a material that makes it possible to withstand the severe stresses (in particular thermal stresses) experienced by the secondary optics 3 and the photovoltaic receiver 2, in particular because of the concentrated flow coming from the concentration systems 14. In the case of reflective optics, the material constituting the support 4 is preferably heat-conducting, so that the support 4 can participate in the heat dissipation of the secondary optics 3. Preferably, the material constituting the support 4 is also chosen so that its coefficient of expansion is adapted to that of the secondary optics 3, to avoid:

dislodging the secondary optics 3 from the fixing means 46 of the support 4 (which could be the case in the event of significant variations in the thermal coefficients of the secondary optics 3 and the support 4),

modifying the centering of the secondary optics 3 with respect to the photovoltaic cell 22, and

- Mark the secondary optics 3 in case of deformation, which may induce local thermal runaway.

Finally, when the base 40 is brazed on the receiver 2, the material constituting the support 4 must be chosen so as to allow such brazing. For example, the support 4 may be made of an aluminum alloy sheet, bronze, copper, or in a ceramic covered with a layer of copper, the finish of this layer may be made of nickel with or without Gold, pewter or silver protection, etc.

The fins 50 are preferably deformable in order to allow the secondary optics 3 to be fixed by sliding and, if necessary, by snapping, and to dismantle, if necessary, the secondary optics 3 of the receiver 2, for example in order to perform a quality control of the assembly 1.

An assembly 1 according to the invention can then be manufactured as follows.

During a first step S1, the support 4, which can be obtained by stamping as described above, is fixed on the photovoltaic receiver 2, preferably by soldering on the substrate 20. In order to be able to leave free access to the Photovoltaic cell 22, the electrical contacts 23 and 21 beaches, the support 4 is preferably fixed so that the peripheral edge 42 of the base 20 is around these elements.

The encapsulant can then be applied (step S2) in the through opening 44 of the base 40, so as to cover the photovoltaic cell 22. Advantageously, the fixing of the support 4 on the substrate 20 limits the extension of the encapsulant. The encapsulant is then polymerized (step S3).

The photovoltaic receiver is then ready to receive the secondary optics 3. For this, the secondary optics is inserted into the fins 50 of the support 4, by introducing its guide ribs 38 into the guide grooves 52 of the vanes for sliding (step S4) to its operating position. This installation is done in a fluid and non-degrading manner, which ensures the integrity of the secondary optics during its implementation. When the secondary optics 3 comes into contact with the fixing means 46, that is to say when its cutouts 36 abut against the protuberances 46, it is then in the operating position. This operating position is chosen so as to optimize the luminous flux received by the photovoltaic cell 22, while respecting a minimum distance between the cell 22 and the output section 35 of the secondary optics 3 in order to avoid the risks of breakdown. .

Where appropriate, when the assembly 1 comprises a non-return system, for example by latching, the detent members take position to prevent the withdrawal and movement of the secondary optics 3 relative to the photovoltaic cell 22. Thus in the exemplary embodiment illustrated in FIGS. 1 to 7, the resilient tongues 53 are housed in the notches 39.

The assembly 1 is then ready to be used in a photovoltaic module 10.

In the case of a refractive 3 'secondary optic, the support 4' also comprises means of guide means 52 ', 54' configured to center the secondary optic 3 'in space with respect to the photovoltaic cell 22, and fixing means 46 'forming a stop for the secondary optics 3' and configured to block the secondary optics 3 in position relative to the photovoltaic cell 22.

An example of refractive 3 'secondary optics and associated assembly 1 has been illustrated in FIGS. 9 to 11. Such refractive optics can include:

a base 30 ', adapted to be arranged facing the photovoltaic cell 22, against the encapsulant 24 which serves as an optical link between the photovoltaic cell 22 and the cell 22, and

a dome 34 'whose outer surface is adapted to direct the light rays on the photovoltaic cell 22.

The base 30 'may comprise a substantially planar peripheral contour 31' and have, at its lower surface 35 ', a cap 32 'of concave shape (Figures 9 and 10). In this embodiment, it is therefore the cap 32 'of the base 30' which comes into contact with the encapsulant. Alternatively, the base 30 'could also comprise a lower surface 35' without cap and substantially flat (Figure 1 1).

The base 30 'of the secondary optics may be circular (FIGS.

10) or square (Figure 1 1).

The refractive optic 3 'may for example be made of glass.

Advantageously, the fixing means 46 'form a Z stop, or in the normal direction to the plane of the photovoltaic cell 22, which relieves the encapsulant 24, which furthermore plays the function of mechanical resistance between the refractive secondary optical 3 'and the photovoltaic cell 22. The fixing means may for example be protuberances 46' protruding from the base 40 'of the support 4' and adapted to bear against a lower surface 35 'of the base 30 'of the refractive secondary optics 3'.

In the case of an assembly V comprising a refractive 3 'secondary optic, the support 4' also comprises a base 40 'which can be soldered on the receiver 2, or even the substrate 20 as well as fins 50'.

The structure of the support 4 'is however adapted to the particular shape of the refractive 3' secondary optics. Thus, the fins 50 'may comprise for example:

a first flexible wall 52 'adapted to come into contact with a peripheral edge of the base 30' and form a stop for the secondary optics 3 ', and

a recess 54 ', extending from the first wall, adapted to come into contact with the upper face of the base 30' of the secondary optic 3 '.

The recess 54 'thus cooperates with the base 30' of the secondary optics 3 to guide it to its operating position and keep it in position by snapping. In the case of a square base, the support 4 'comprises four fins 50', namely one facing each edge of the base 30 ', to form X and Y stops for the secondary optics 3'. In the case of a generally circular base, the support 4 'may comprise only two fins 50' facing globally curved shape,

Moreover, in a similar manner to the case of the support 4 of the reflective secondary optics 3, the base 40 'of the support 4' of the refractive secondary optic 3 comprises a peripheral rim 42 'which delimits an opening 44' passing through which the cell 22, the electrical contacts 23 and the lands 21 of the substrate 20 may be exposed, in order to allow the passage of the light rays, which may further delimit the extension of the encapsulant.

It will be noted that, in the case of a refractive secondary optic 3 ', the assembly 1' can be manufactured in a similar manner to the case of the secondary reflective optics, with the difference that the encapsulant is polymerized after positioning of the secondary optics 3 'on the encapsulant.

An assembly 1, 1 'according to the invention can then be fixed on a dissipator 5, for example aluminum, then be integrated in a photovoltaic module 10.

For this, the assembly 1, 1 'can be fixed in a bottom wall of the photovoltaic module 10, for example by gluing. Preferably, each photovoltaic module 10 comprises a series of such assemblies 1, 1 ', for example ten, positioned very precisely in the focal center of as many concentration systems 14. For this, the photovoltaic module 10 comprises:

a bottom wall 1 1 adapted to fix in position a series of assemblies 1, 1 ',

a front face 12, adapted to fix in position a series of concentration systems 14, and - Side walls 13, connecting the bottom wall 1 1 and the front face 12 so as to define a closed box.

The support 4 of the secondary optics, when made of a conductive material, can then serve as a connector between two adjacent assembled dissipators 5 of the photovoltaic module 10, in order to put the heatsinks 5 in series two by two, for example at the using a suitable electric cable.

Claims

1. Assembly (1, 1 ') comprising:

a photovoltaic receiver (2) on which a photovoltaic cell (22) is fixed,

a secondary optics (3, 3 '), and

a support (4, 4 '), adapted to position and fix the secondary optics (3) with respect to the photovoltaic cell (22), comprising guiding means (52, 38, 54'), configured to implement place and center the secondary optics (3, 3 ') in the space with respect to the photovoltaic cell (22), and fixing means (46, 46') forming a stop for the secondary optics (3, 3 ') and configured to block the secondary optics (3, 3') in an operating position with respect to the photovoltaic cell (22), the assembly being characterized in that,

the support (4, 4 ') comprises a base (40, 40'), fixed on the photovoltaic receiver (2), and two fins (50), extending from the base (40, 40 '), each fin (50) comprising central walls (54) adapted to engage sidewalls (30, 32) of the secondary optics (3) to participate in the heat dissipation of the secondary optics (3), and

the guide means (52, 38) comprise guide grooves (52) and associated guide ribs (38) formed in the fins (50) of the support (4) and in the secondary optics (3), in order to allow the sliding of the secondary optics (3) and its progressive guidance towards its operating position by the support (4), the guide grooves (52) of each fin (50) extending from both sides other of the central wall (54).

2. Assembly (1, 1 ') according to claim 1, wherein the photovoltaic receiver (2) comprises a substrate (20) on which are fixed the photovoltaic cell (22) and the support (4, 4').

3. The assembly (1, 1 ') according to claim 2, wherein the base (40, 40') of the support (4, 4 ') is brazed to the substrate (20).

4. Assembly (1, 1 ') according to one of claims 1 to 3, wherein the photovoltaic receiver (2) comprises a substrate (20) provided with pads (21), the photovoltaic cell (22) being connected to the substrate (20) via electrical contacts (23), and wherein the base (40, 40 ') of the support (4, 4') comprises a peripheral edge (42, 42 ') defining an opening (44, 44 ') through which can be exposed the photovoltaic cell (22), said electrical contacts (23), and possibly a portion of the pads (21) of the substrate (20).

5. Assembly (1, 1 ') according to claim 4, wherein the photovoltaic receiver (2) further comprises an encapsulant adapted to protect the photovoltaic cell (22), the extension of the encapsulant on the substrate (20) being delimited by the opening (44 ') through the base (40') of the support (4 ').

6. The assembly (1, 1 ') according to one of claims 1 to 5, wherein the fixing means (46, 46') comprise protuberances (46,

46 '), adapted to abut against a lower face (35, 35') of the secondary optics (3, 3 ').

7. The assembly (1, 1 ') according to claim 6, wherein the lower face (35, 35') of the secondary optics (3, 35 ') comprises cutouts.

(36) adapted to receive the protuberances (46) of the fastening means (46).

8. Assembly (1, 1 ') according to one of claims 1 to 7, wherein the fins (50) and the secondary optics (3, 3') comprise detent members (53, 39, 54 '). , 30 ') forming a non-return system so as to form a stop for the secondary optics (3, 3').

9. Assembly (1, 1 ') according to claim 8, wherein the detent members (53, 39) comprise notches (39) and tabs (53) resilient, the notches (39) being each adapted to receive an elastic tongue.

10. The assembly (1, 1 ') according to one of claims 1 to 9, wherein the guide means (52, 38) comprise guide grooves (52) and associated guide ribs (38), formed in the fins (50) of the support (4) and in the secondary optics (3), to allow the sliding of the secondary optics (3) and its progressive guidance to its operating position by the support (4).

1 1. An assembly (1, 1 ') according to claim 10, wherein the guide grooves (52) are formed in the fins (50), while the guide ribs (38) project from the secondary optics (3).

12. The assembly (1, 1 ') according to claim 10, wherein the guide ribs (38) are formed by edges of the side walls (31, 33) of the secondary optics (3).

13. The assembly (1, 1 ') according to one of claims 1 to 12, wherein the support (4, 4') is made of an aluminum alloy, bronze, copper, or in a ceramic covered with a layer of copper, the finish of this layer can be made of nickel with or without gold protection, tin or silver.

14. Assembly (1, 1 ') according to one of claims 1 to 13, wherein the secondary optics (3) is reflective.

15. Support (4) for secondary optics (3) of an assembly (1, 1 ') according to one of claims 1 to 14, said support (4) being adapted for positioning and fixing the secondary optics (3) with respect to a photovoltaic cell (22) of the photovoltaic receiver (2), and comprising guiding means (52, 38), configured to set up and center the secondary optics ( 3) in the space with respect to the photovoltaic cell (22), and fixing means (46) forming a stop for the secondary optics (3) and configured to block the secondary optics (3) in position relative to to the photovoltaic cell (22)

said support being characterized in that it further comprises a base (40, 40 '), fixed on the photovoltaic receiver (2), and two fins (50), extending from the base (40, 40'), each wing (50) comprising central walls (54) adapted to come into contact with side walls (30, 32) of the secondary optics (3) to participate in the heat dissipation of the secondary optics (3), and in that the guide means (52, 38) comprise guide grooves (52) and associated guide ribs (38) formed in the fins (50) of the support (4) and in the secondary optics ( 3), in order to allow the sliding of the secondary optics (3) and its progressive guidance towards its operating position by the support (4), the guide grooves (52) of each fin (50) extending from and other of the central wall (54).

16. Secondary optic (3), characterized in that it is adapted to be positioned and fixed on a photovoltaic receiver (2) of an assembly (1, 1 ') by means of a support (4) according to claim 15.

17. Secondary optic (3) according to claim 16, comprising means adapted to cooperate with the guide means (52, 38) and the fixing means (46) of the support (4).

Photovoltaic module (10), comprising:

- a bottom wall (1 1) adapted to fix in position a series of assemblies (1, 1 ') according to one of claims 1 to 14, a front face (12), adapted to fix in position a series of concentration systems (14), and

- Side walls (13), connecting the bottom wall (1 1) and the front face (12) so as to define a closed box.

19. Photovoltaic module according to claim 18, wherein the support (4) of the assemblies (1, 1 ') is made of a conductive material, the assemblies (1) being connected electrically in pairs in series via their support (4).

20. Manufacturing method (S) of an assembly (1, 1 ') according to one of claims 1 to 14, characterized in that the secondary optics (3) is fixed on the receiver (2) according to the steps following successive

- placing and centering (S4) of the secondary optics (3) in the guide means (52, 38) of the support (4), then

- Fixing (S5) the secondary optics (3) in its operating position by means of the fixing means (46) of the support (4).

21. Manufacturing method (S) according to claim 20, wherein the secondary optics (3) is further snap-fastened (53, 39) in the fastening means (46) of the support (4).

22. Manufacturing method (S) according to one of claims 20 or 21, wherein the photovoltaic receiver (2) comprises a substrate (20) on which is fixed the photovoltaic cell (22),

the method (S) further comprising, prior to the steps of placing and centering (S4) and fixing (S5) of the secondary optics (3), a step (S1) in which the support (4) is soldered to the substrate (20) of the photovoltaic receiver (2).

23. Manufacturing method (S) according to claim 22, wherein the support (4) comprises a peripheral edge (42) defining a opening (44), and during the step (S1) soldering, the peripheral edge (42) of the support (4) being fixed around the photovoltaic cell (22) so that the photovoltaic cell (22) is located facing the opening (44) of the base (40) of the support (4).

24. The manufacturing method (S) according to claim 23, wherein the photovoltaic receiver (2) further comprises an encapsulant adapted to protect the photovoltaic cell (22),

the method (S) further comprising a step in which the encapsulant is applied (S2) to the photovoltaic cell (22) and is polymerized (S3).