CN104796087A - Photovoltaic cell concentration test device - Google Patents

Abstract

The present application discloses a photovoltaic cell concentration test device, which includes: a support, including a guide rod extending along the Z-axis direction; Diaphragm, and the lens located below the diaphragm; the mobile platform slides on the guide rod along the Z-axis direction; the workbench includes a first workbench and a second workbench, and the first workbench is along the Y-axis direction slides on the moving platform, the second workbench is located on the first workbench, and is movable along the X-axis direction relative to the first workbench, and the second workbench has a The bearing surface of the battery sheet; the battery sheet fixing device; the secondary uniform light system, located between the lens and the workbench. The aperture is set between the light source and the condenser lens, which can output a large area of uniform parallel light, and by continuously adjusting the area of the aperture of the aperture, the total light energy received by the cell to be tested can be continuously adjusted.

Description

Photovoltaic cell concentration test device

technical field

The present application belongs to the field of photovoltaics, and in particular relates to a photovoltaic cell concentration testing device.

Background technique

In recent years, as a new type of renewable energy, solar cells have attracted more and more attention, and their status in the energy industry has become more and more important. With the continuous development of solar technology and people's continuous in-depth exploration of high-efficiency solar cells, the concentrating solar cell system composed of multiple PN-structured high-efficiency solar cells and concentrating components is bound to become the mainstream of solar cell applications. .

For solar cells with multiple PN junctions, in the actual application process, they often do not work directly under outdoor sunlight, but gather a large area of sunlight to a small cell surface through a concentrating lens, so that The surface unit area of the solar cell receives light intensity several times or even hundreds of times higher than that of ordinary sunlight (depending on the ratio of the lens area to the focal spot size of the lens), so that a solar cell of the same size can produce more High output current (the output current will be proportional to the light concentration multiple) and output voltage, so the output power of the solar cell can be greatly improved.

However, the current-voltage characteristics of solar cells also change under different light intensities and different temperatures. Therefore, it is necessary to test whether a battery with good performance under the condition of 1 standard sunlight (outdoor sunlight) still has excellent current-voltage characteristics under high concentration conditions, and it is hoped to find out at what concentration multiples the battery can Output the highest output power, the highest energy conversion efficiency under the concentrating multiple, etc. The solar cell concentration test system is a system that can test the current and voltage performance of solar cells and effectively record the test data (open circuit voltage, short circuit current, fill factor) under conditions that are several times or hundreds of times higher than ordinary sunlight. , efficiency, series resistance, parallel resistance, etc.) and a complete system of current-voltage curves.

In the current solar cell concentration test field, the concentration test is often achieved by adding a condenser lens or directly replacing the traditional xenon lamp light source with a high-intensity light source. However, due to the existence of scattered light and the loss of light in the propagation path, the condensing power is not linearly proportional to the distance from the condensing lens to the battery surface, so the condensing power cannot be calibrated accurately and quantitatively. In other words, under the condition of a certain light intensity, the existing concentrating test systems using Fresnel lenses can only increase or decrease the concentrating power simply by changing the position of the Fresnel lens, and testers cannot Accurately know the concentration multiple of the light spot irradiated on the surface of the battery.

In addition, the system that uses the spotlight light source to realize the spotlight test, that is, directly replaces the standard light source with a spotlight source with a certain spotlight multiple, and directly tests the battery without adding any spotlight lens. In this way, although a single concentration factor can be determined quantitatively, the non-adjustable concentration factor of the measured spot is a major disadvantage, and the concentrated light source is expensive and difficult to be widely used.

Chinese patent No. 201210558836.4 discloses a solar cell concentration test system, which can adjust the concentration factor by setting a diaphragm, and at the same time, the tester can accurately know the concentration factor of the light spot irradiated on the surface of the battery. However, it sets the diaphragm below the condenser lens, which has the following disadvantages: due to the high energy of the convergent beam after being converged by the lens, the local temperature of the diaphragm will be significantly increased, and the convergent beam with high energy concentration ratio After being scattered by the diaphragm, the temperature of other components near the diaphragm will also increase significantly, thus bringing potential risks to the stability of the system.

Contents of the invention

The object of the present invention is to provide a photovoltaic cell concentration test device to solve the problems in the prior art that the concentration factor cannot be accurately determined, the concentration factor cannot be continuously adjusted in a wide range, and the local temperature of the diaphragm increases significantly.

To achieve the above object, the present invention provides the following technical solutions:

The embodiment of the present application discloses a photovoltaic cell concentration test device, including:

A bracket, including a guide rod extending along the Z-axis direction;

A light-condensing system installed on the bracket, the light-condensing system includes a diaphragm with an adjustable aperture, and a lens located below the diaphragm;

The mobile platform slides on the guide rod along the Z-axis direction;

The workbench includes a first workbench and a second workbench, the first workbench slides on the moving platform along the Y-axis direction, the second workbench is located on the first workbench, and is relatively The first workbench is movable along the X-axis direction, and the second workbench has a bearing surface capable of carrying the tested cell;

Cell fixing device;

The secondary homogenization system is located between the lens and the workbench.

Preferably, in the photovoltaic cell concentration testing device above, the mobile platform has an extension, and the worktable can move onto the extension along the Y-axis direction.

Preferably, in the photovoltaic cell concentration testing device described above, the cell fixing device includes at least one reversible elastic sheet, each elastic sheet is provided with a test probe, and the elastic sheet is also provided with a fixing part. A plurality of angle control slots are opened on the fixing part, and the test probes are detachably installed in the angle control slots.

Preferably, in the photovoltaic cell concentration testing device described above, a downwardly protruding presser foot is fixed at the bottom of the end of each elastic piece.

Preferably, in the photovoltaic cell concentration testing device described above, one of the presser feet of the elastic piece includes a heat-conducting contact portion and an insulating portion between the heat-conducting contact portion and the elastic piece, and the heat-conducting contact portion has an accommodating A temperature sensor is provided in the accommodating space, and the presser feet of the rest of the spring pieces are all made of insulating materials.

Preferably, in the photovoltaic cell concentration testing device described above, the cell fixing device includes a motor and a driving part fixed on the output shaft of the motor, the elastic piece is installed on the driving part, and can be positioned relative to the The driving part moves axially.

Preferably, in the above photovoltaic cell concentration test device, it also includes a power device that drives the mobile platform to move along the Z axis, the power device includes a motor and a screw that can be driven by the motor to rotate, the moving Bolts are fixed on the platform, and the bolts have internal threads matching the screw rods.

Preferably, in the photovoltaic cell concentration testing device described above, a heat dissipation space is provided under the bearing surface, and a water-cooling heat dissipation device is provided in the heat dissipation space.

Preferably, in the photovoltaic cell concentration test device above, the secondary uniform light system is a light funnel or a parallel light lens.

Preferably, in the photovoltaic cell concentration testing device above, the secondary uniform light system is installed on a three-dimensional motion platform, and the three-dimensional motion platform is fixed on the guide rod.

Compared with the prior art, the present invention has the advantages of:

1. The aperture is set between the light source and the condenser lens. On the one hand, the light irradiated or passed through the aperture at this time is still a large and uniform parallel light output by the simulated light source. Generally, the energy density is near the intensity of a sun, and the energy The density is much lower than the energy density of the converging beam after the lens converges, which can avoid the local temperature of the diaphragm from rising obviously; The continuous adjustment of the area of the diaphragm aperture can realize the continuous adjustment of the total light energy received by the cell to be tested, that is, the continuous adjustment of the light concentration multiple.

2. The uniform light system uses a light funnel or a trapezoidal prism. On the one hand, it can use the multiple total reflections of the converging beam in the light funnel or trapezoidal prism to achieve the effect of uniform light; on the other hand, because the indoor sunlight simulates the light source, it is different after all. For real sunlight, the uniform light structure in the simulated light source system, etc., such as the commonly used compound eye uniform light structure, will be imaged on the surface of the device under test, resulting in uneven light received by the cell in the light concentration test. Light homogenization systems such as light funnels or trapezoidal prisms can overcome the unevenness of light caused by the lens imaging the light source system; finally, according to the shape of the battery, the bottom plane of the light funnel or trapezoidal prism can be designed to be the same size as the battery shape. In order to match the spot shape of the spotlight with the shape of the battery.

3. The workbench is set to move in three dimensions. On the one hand, after the sample is fixed, the test sample can be quickly moved to the bottom of the light funnel or trapezoidal prism. At the same time, it can cooperate with the three-dimensional movement of the light funnel or trapezoidal prism to realize the maximum irradiation of the converging beam in the On the other hand, when testing different light concentration multiples, the three-dimensional movement of the workbench and the secondary uniform light system can also be used to facilitate the realization of changes in the optical path caused by changing the light concentration multiples. fix.

4. The workbench is set as a drawer type. When replacing the battery sheet, the workbench can be moved to the extension along the slide rail to facilitate sample replacement.

5. Different from the general vacuum adsorption fixing method, the present invention adopts the presser foot fixing method with shrapnel, which can ensure the full contact between the cell and the water-cooled control sample stage, thereby facilitating the heat dissipation of the cell to be tested under high-power concentrating.

6. There is a temperature sensor on the shrapnel, which can measure the surface temperature of the cell in real time; a cooling device is installed under the bearing surface, which can control the temperature of the bearing surface in real time; the probe is installed on the shrapnel through the fixed part, and there are multiple There are three angle control grooves, the inclination angle of the probe is adjustable, and each angle control groove makes the probe have different inclination angles. During operation, the inclination angle of the probe can be adjusted according to the needs of different contact forces.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments described in this application. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 shows the schematic diagram of the three-dimensional structure of the photovoltaic cell concentration test device in a specific embodiment of the present invention;

Fig. 2 is a schematic cross-sectional view of a light concentrating system in a specific embodiment of the present invention;

Fig. 3 is a side view of a photovoltaic cell concentration testing device in a specific embodiment of the present invention;

Fig. 4 shows the top view of the clamping device in a specific embodiment of the present invention;

Figure 5 is a cross-sectional view of the clamping device in a specific embodiment of the present invention (without a temperature sensor);

Fig. 6 is a cross-sectional view of the clamping device (with temperature sensor) in a specific embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As shown in Fig. 1, the photovoltaic cell testing device includes a support 10, the support 10 includes a horizontally arranged bottom plate 11 and a top plate 12, the top plate 12 is located directly above the bottom plate 11, and four guide rods 13 are supported between the bottom plate 11 and the top plate 12, Define the X-Y-Z axis coordinate system, the guide rod 13 extends along the Z-axis direction (vertical direction), the bottom plate 11, the top plate 12 and the four guide rods 13 form a working space, and the outside of the working space can also pass through the mask (not shown in the figure) ) for sealing, and an observation window (not shown) formed of glass material may also be provided on the mask.

A concentrating system 20 is fixed on the top plate 12, and the concentrating system 20 receives simulated sunlight emitted by a sun simulation light source and outputs a converging light beam with a certain energy concentrating ratio. As shown in FIG. 2 , the focusing system 20 includes an aperture 21 with an adjustable aperture and a lens 22 located below the aperture 21 .

The diaphragm 21 is set between the light source and the condenser lens 22. On the one hand, the light irradiated or passed through the diaphragm at this time is still a large and uniform parallel light output by the simulated light source. Generally, the energy density is near the intensity of a sun, and the energy The density is much lower than the energy density of the converging beam after the lens converges, which can avoid the local temperature of the diaphragm from rising obviously; The continuous adjustment of the area of the diaphragm aperture can realize the continuous adjustment of the total light energy received by the cell to be tested, that is, the continuous adjustment of the light concentration multiple.

The photovoltaic battery testing device also includes a mobile platform 30 , which is sleeved on four guide rods 13 and can move along the Z-axis direction under the guidance of the guide rods 13 . The mobile platform 30 has an extension portion 31 along the Y-axis direction, and the extension portion 31 is formed outside the working space. The upper surface of the mobile platform 30 is provided with a slide rail 32 along the Y-axis direction, and the slide rail 32 extends to the extension portion 31 .

The photovoltaic battery testing device also includes a power device 40 that drives the mobile platform 30 to move. The power device 40 includes a support frame 41 , a motor 42 and a screw 43 driven by the motor 42 to rotate. The support frame 41 is fixed on the base plate 11, the motor 42 is fixed on the support frame 41, the screw rod 43 is fixed on the output shaft of the motor 42, and the mobile platform 30 is fixed with a bolt 44, and the bolt 44 has an internal thread that cooperates with the external thread of the screw rod 43. . The motor 42 drives the screw rod 43 to rotate, and the rotation of the screw rod 43 drives the bolt 44 to rise or fall, and the bolt 44 further drives the entire mobile platform 30 to move along the Z-axis direction.

A workbench 50 is provided in the working space, and the workbench 50 is located on the mobile platform 30 and can move in the Z-axis direction under the support of the mobile platform 30 . As shown in FIG. 3 , the workbench 50 includes a first workbench 51 and a second workbench 52 sliding on the first workbench 51 along the X-axis direction, and the first workbench 51 slides along the slide rail 32 to move On the platform 30, the second workbench 52 has a bearing surface capable of bearing the battery slices under test.

Under the combined action of the mobile platform 30, the first workbench 51 and the second workbench 52, the bearing surface can realize three-dimensional movement, wherein the mobile platform 30 controls the movement of the bearing surface in the Z-axis direction, and the first workbench 51 moves along the slide rail. 32 movement controls the movement of the bearing surface in the Y-axis direction, and the movement of the second working platform 52 relative to the first working platform 51 controls the movement of the bearing surface in the X-axis direction.

Using such a three-dimensional mobile working method, on the one hand, after the sample is fixed, the test sample can be quickly moved to the bottom of the light funnel or trapezoidal prism, and at the same time cooperate with the three-dimensional movement of the light funnel or trapezoidal prism to realize the maximum irradiation of the converging beam on the battery surface, thereby reducing light loss; on the other hand, when performing tests with different concentration ratios, the three-dimensional movement of the workbench and the secondary homogenization system can also be used to facilitate the correction of changes in the optical path caused by changing the concentration ratio .

The workbench 50 can be moved to the extension part 31 through the slide rail 32, so as to realize the replacement of battery slices.

The movement of the first workbench 51 and the second workbench 52 can be controlled manually or by motors.

A heat dissipation space may also be provided under the carrying surface, and a circulating water-cooling heat dissipation device is preferably provided in the heat dissipation space.

The photovoltaic cell testing device also includes a cell fixing device 60, and the cell fixing device 60 includes two clamping devices 61 symmetrically arranged on both sides of the bearing surface. As shown in Fig. 4, each clamping device 61 includes a motor 611 and a driving part 612 fixed on the output shaft of the motor 611. Two shrapnels 613 are installed on the driving part 612, and the driving part 612 is driven by the motor 611 to rotate, and then The shrapnel 613 can be driven to turn over, and the turning of the shrapnel 613 can realize the clamping and releasing of the battery piece under test.

The material of the shrapnel 613 is preferably a metal with better elasticity. As shown in FIG. 5, in order to avoid electrical contact between the shrapnel 613 and the battery under test, the bottom of the end of the shrapnel 613 is fixed with a downwardly protruding presser foot 614. The presser foot 614 is made of insulating material, preferably polytetrafluoroethylene.

In order to measure the temperature of the cell surface in real time, a temperature sensor is also provided in the presser foot of one of the elastic pieces 613, as shown in FIG. The material of the insulating part 6142 and the contact part 6141 is preferably copper, and the material of the insulating part 6142 is preferably polytetrafluoroethylene. The contact portion 6141 has an accommodating space 6143 , and a temperature sensor (not shown) is disposed in the accommodating space 6143 .

As shown in FIG. 5 , each elastic sheet 613 is also provided with a probe 615 for testing the electrical performance of the cell. The probe 615 is fixed on the elastic piece 613 through the fixing part 616. The fixing part 616 is provided with a plurality of angle control grooves (not shown in the figure), and the probe 615 is detachably installed in the angle control groove. Each angle control groove makes the probe 615 has different inclination angles. During operation, the inclination angle of probe 615 can be adjusted according to the needs of different contact forces.

The battery sheet fixing device 60 can be fixed on the second workbench 52 and is stationary relative to the second workbench 52. The two clamping devices of the battery sheet fixing device 60 can also move relative to each other to realize approaching and moving away, which can be applied to different Clamping of battery slices of different sizes.

The elastic piece 613 is installed on the driving part 612 and is movable in the axial direction of the driving part 612. Specifically, the driving part 612 is provided with a plurality of installation holes in the axial direction, and the elastic piece 613 can be fixed on the installation holes by screws.

The photovoltaic cell testing device also includes a secondary homogenization system 70, which is located above the bearing surface, so that the converging light beam is uniformly irradiated on the tested cell.

The secondary homogenization system 70 is preferably a light funnel, which receives the converging light beam output by the light concentrating system to meet the total reflection condition, and finally makes the converging light beam evenly irradiate the test battery sheet.

The optical funnel is installed on the three-dimensional motion platform 80, through the control of the three-dimensional motion platform, the three-dimensional movement control of the optical funnel can be realized. On the one hand, when the test sample is replaced, the three-dimensional moving mechanism can control the optical funnel to another working position to realize The protection of the optical funnel, on the other hand, can control the flexible adjustment and recovery of the test light path after the test sample is replaced.

The three-dimensional motion platform is installed on the guide rod 13.

In other embodiments, the secondary homogenization system can also be a parallel light lens, which can convert the light converged by the converging lens into parallel light output. The secondary homogenization system can also be designed in the form of a trapezoidal prism secondary homogenizer, so that the converging beam output by the converging lens passes through the secondary homogenizer under the condition of total reflection and then irradiates the device under test.

The uniform light system uses a light funnel or a trapezoidal prism. On the one hand, it can use the multiple total reflections of the converging beam in the light funnel or trapezoidal prism to achieve the effect of uniform light; on the other hand, because the indoor sunlight simulates the light source, it is different from the real Sunlight will image the uniform light structure in the simulated light source system, such as the commonly used compound eye uniform light structure, on the surface of the device to be tested, resulting in uneven light received by the cell in the light concentration test, and the light used in the present invention Homogenization systems such as funnels or trapezoidal prisms can overcome the influence of light inhomogeneity caused by the imaging of the lens on the light source system; finally, according to the shape of the battery, the bottom plane of the light funnel or trapezoidal prism can be designed to be the same size as the battery shape to achieve The shape of the spotlight matches the shape of the battery.

It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is a relationship between these entities or operations. There is no such actual relationship or order between them. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

The above description is only the specific implementation of the present application. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present application, some improvements and modifications can also be made. It should be regarded as the protection scope of this application.

Claims (10)

1. A photovoltaic cell concentration testing device, characterized in that, comprising: A bracket, including a guide rod extending along the Z-axis direction; A light-condensing system installed on the bracket, the light-condensing system includes a diaphragm with an adjustable aperture, and a lens located below the diaphragm; The mobile platform slides on the guide rod along the Z-axis direction; The workbench includes a first workbench and a second workbench, the first workbench slides on the moving platform along the Y-axis direction, the second workbench is located on the first workbench, and is relatively The first workbench is movable along the X-axis direction, and the second workbench has a bearing surface capable of carrying the tested cell; Cell fixing device; The secondary homogenization system is located between the lens and the workbench. 2 . The photovoltaic cell concentration test device according to claim 1 , wherein the mobile platform has an extension, and the worktable can move to the extension along the Y-axis direction. 3 . 3. The photovoltaic cell concentration test device according to claim 1, characterized in that: the cell fixing device includes at least one reversible elastic sheet, each elastic sheet is provided with a test probe, and the elastic sheet is also provided with a test probe. There is a fixed part, and a plurality of angle control grooves are opened on the fixed part, and the test probes are detachably installed in the angle control grooves. 4 . The photovoltaic cell concentration testing device according to claim 3 , wherein a presser foot protruding downward is fixed on the bottom of each elastic piece end. 5 . 5. The photovoltaic cell concentration testing device according to claim 4, wherein the presser foot of one of the elastic pieces includes a heat-conducting contact portion and an insulating portion between the heat-conducting contact portion and the elastic piece, and the heat-conducting contact portion and the elastic piece are insulated. The contact part has an accommodating space, and a temperature sensor is arranged in the accommodating space, and the presser feet of the other elastic pieces are all made of insulating materials. 6. The photovoltaic cell concentrating test device according to claim 3, characterized in that: the cell fixing device includes a motor and a driving part fixed on the output shaft of the motor, and the elastic piece is installed on the driving part and can move axially relative to the driving part. 7. The photovoltaic cell concentration test device according to claim 1, characterized in that: it also includes a power unit that drives the mobile platform to move along the Z axis, and the power unit includes a motor and can be driven by the motor to rotate a screw rod, bolts are fixed on the mobile platform, and the bolts have internal threads matching the screw rods. 8 . The photovoltaic cell concentration test device according to claim 1 , wherein a heat dissipation space is provided under the bearing surface, and a water cooling device is provided in the heat dissipation space. 9 . 9. The photovoltaic cell concentration testing device according to claim 1, characterized in that: the secondary uniform light system is a light funnel or a parallel light lens. 10. The photovoltaic cell concentration testing device according to claim 1, wherein the secondary uniform light system is installed on a three-dimensional motion platform, and the three-dimensional motion platform is fixed on the guide rod.