CN102736010B - Indoor wide-spectrum wide-visual-angle condensation photovoltaic solar cell testing device - Google Patents

Abstract

The invention provides an indoor wide-spectrum and large-field-of-view concentrating photovoltaic solar cell test device, the main function of which is to realize the test of III-V group concentrating solar cells under different concentrating multiples, including an optical platform, a simulated light source, and a battery fixture And the test system, the simulated light source located on the optical platform emits light, the test system measures the photovoltaic characteristic curve of the solar cell to be tested, it is characterized in that it also includes a concentrating system, and the concentrating system includes focusing mirrors arranged in sequence in the optical path , field lens and collimating lens, the light is focused on the solar cell to be tested through the concentrating system. The invention has the advantages of stably simulating sunlight, adjustable light source intensity, wide spectrum and large viewing angle, and multiple focusing multiples.

Description

An indoor wide-spectrum and large-field-of-view concentrating photovoltaic solar cell testing device

technical field

The invention relates to the field of solar cell testing.

Background technique

Today, as fossil resources are increasingly scarce, solar photovoltaic applications, as a clean and non-polluting energy output method, have very good application prospects. However, due to the limitation of high solar cell production costs, the promotion of photovoltaic applications has been affected. Because the cost of photovoltaic applications is mainly concentrated on photovoltaic cells, the use of concentrated photovoltaic technology can generate greater energy output on smaller solar cells than ordinary solar cells of the same area.

Concentrating photovoltaics directly convert sunlight into electricity through high conversion efficiency photovoltaic cells after concentration, so that part of the cost is transferred from the photovoltaic cells themselves to the focusing system and solar tracking system, which is an effective way to reduce the system cost of photovoltaic applications .

Compared with traditional monocrystalline silicon or polycrystalline silicon cells, concentrating photovoltaics usually use higher-efficiency III-V semiconductor materials as triple-junction cell materials, so that cells can absorb sunlight with a wider spectrum and achieve higher power generation efficiency. The record for the efficiency of this type of triple-junction cell in 2011 has reached 41.4%, and this efficiency has been confirmed by the US Renewable Energy Laboratory.

With the continuous development of concentrated photovoltaic technology, researchers have invented various forms of concentrated solar cells and modules. For example, Chinese patent application No. 200910061751.3 discloses a solar cell parameter testing device, which includes a simulated light source, a parameter tester and a test platform. The simulated light source is located above the test platform, and a cooling device is provided below the test platform. It is not equipped with a concentrating device, which is suitable for the situation where the divergence angle of the simulated light source outlet is small. For the case where the divergence angle of the simulated light source outlet is large, the test effect is not good. In order to test and develop different batteries, a concentrating photovoltaic solar cell testing device that can simulate sunlight and adjust the intensity of the light source, has a wide spectrum, large field of view, and multiple focusing multiples is needed.

Contents of the invention

The technical problem solved by the present invention is to provide an indoor wide-spectrum large-field-angle concentrating photovoltaic solar cell testing device with stable sunlight simulation, adjustable light source intensity, wide-spectrum large field-of-view, and multiple focusing multiples.

In order to solve the above technical problems, the technical solution adopted by the present invention is to provide an indoor wide-spectrum and large-field-of-view concentrating photovoltaic solar cell testing device, including an optical platform, a simulated light source, a battery fixture and a testing system. The simulated light source emits light, and the test system measures the photovoltaic characteristic curve of the solar cell to be tested. It is characterized in that it also includes a concentrating system. The concentrating system focuses the light on the solar cell to be tested.

Further, the focusing mirror is placed at the exit of the simulated light source, the field lens is placed at the focal point of the focusing mirror, and the focal point of the collimating mirror coincides with the focal point of the focusing mirror. The measurement of the focus of the focusing mirror uses green light with a wavelength of 526.1nm.

Further, the test system includes an optical power meter for measuring light intensity and a digital source meter for measuring photovoltaic characteristic curves, and the data obtained by the two measurements are transmitted to the data processing system.

Further, the battery fixture is a temperature-controlled battery fixture.

Furthermore, the temperature-controlled battery fixture includes a vacuum pump at the front and a water-cooled heat exchanger at the rear. Concentrating solar cells are adsorbed on the temperature-controlled cell fixture during the test, and the adsorption force is provided by a vacuum pump.

Furthermore, the cold water used by the water-cooled heat exchanger is provided by a water cooler, and the coil of the water-cooled heat exchanger is a double-helix structure, which can obtain a more stable and uniform temperature distribution.

Furthermore, the cooling water inlet and outlet of the water-cooled heat exchanger and the surface of the battery fixture are provided with temperature probes to transmit temperature measurement data to the data processing system.

Further, the simulated light source is a steady-state simulator of an AM1.5D filter.

Compared with the prior art, the beneficial effect is:

(1) The present invention has a large viewing angle. The existing technology is suitable for the situation where the divergence angle of the exit of the simulated light source is small, but the present invention can be used in the case of a large divergence of the exiting light of the simulated light source through the design of the concentrating system.

(2) The present invention has a wider spectrum (300~1800nm) and smaller dispersion, and is especially suitable for testing III-V multi-junction solar cells.

(3) The present invention has a more uniform temperature control system, combined with a data processing system, the battery temperature can be calculated, and the obtained volt-ampere characteristic curve is more accurate.

Description of drawings

Fig. 1 is the optical path schematic diagram of focusing system of the present invention;

Fig. 2 is a schematic diagram of the device of the present invention;

Fig. 3 is the optical path schematic diagram of the present invention;

4 is a schematic structural view of the battery clamp of the present invention;

Fig. 5 is a schematic diagram of the workflow of the present invention;

Fig. 6 is the simulated light spot analysis figure of the embodiment of the present invention;

Fig. 7 is a spot energy analysis diagram of the embodiment of the present invention;

Among them: 1, optical platform; 2, simulated light source; 3, focusing mirror; 4, field mirror; 5, collimating mirror; 6, digital source meter; 7, battery fixture; 8, optical power meter; 9, data processing system 10, the solar cell to be tested; 11, the vacuum pump; 12, the battery adsorption place; 13, the temperature probe; 14, the electrode; 15, the water cooler; 16, the water-cooled heat exchanger.

Detailed ways

The present invention will be further described below in conjunction with accompanying drawing.

The invention provides an indoor wide-spectrum and large-field-of-view concentrating photovoltaic solar cell testing device, the main function of which is to realize the test of III-V group concentrating solar cells under different concentrating multiples, including an optical platform 1, a simulated light source 2, The battery fixture 7 and the test system, the simulated light source 2 located on the optical platform 1 emits light, and the test system measures the photovoltaic characteristic curve of the solar cell 10 to be tested, and also includes a light concentrating system, which includes sequentially arranged in the light path The focusing lens 3 , the field lens 4 and the collimating lens 5 focus the light on the solar cell 10 to be tested through a concentrating system. Using the steady-state simulator of AM1.5D filter as the simulated light source 2, through different focusing mirrors 3, field mirrors 4 and collimating mirrors 5, different focusing multiples are realized, and the light is gathered and illuminated on the sample battery to be tested 10 on. The focus mirror 3 is placed at the exit of the analog light source 2, the field lens 4 is placed at the focus of the focus mirror 3, and the focus of the collimator mirror 5 coincides with the focus of the focus mirror 3. The measurement of the focal point of the focusing mirror 3 uses green light with a wavelength of 526.1nm.

The solar cell 10 to be tested is adsorbed on the temperature-controlled cell fixture 7, and the electrodes are connected to the digital source meter 6 to scan the volt-ampere characteristic. The electrodes are attracted to the side plates by magnets and can move and rotate freely. The probe is a high-current elastic probe, which is used to compress the electrodes of the solar cell 10 to be tested. Finally, the scanning results are processed to obtain the volt-ampere characteristic curve under standard conditions.

The concentrating system consists of three parts. The first part is the focusing lens 3. The focusing lens 3 should consider three aspects. aberrations. In summary, this embodiment uses a compound lens as the focusing lens 3, and in order to eliminate aberration, fluorite (CaF2) is selected as the positive lens, and optical quartz glass (UV Fused Silica) is used as the negative lens. Considering that the lens group works at a higher temperature, the two lenses are not cemented. Formula (1) is an aberration analysis formula, which is used to optimize the parameters of positive and negative lenses. The selected material can also be fluorite (CaF2) as a positive lens, and optical quartz glass (UV Fused Silica) with a similar refractive index and Abbe number.

(1)

The second part is the field lens 4, which is for the system to obtain a larger field of view. The third part is the collimating mirror 5 . The reason why the field lens 4 is used is that the focusing lens 3 cannot focus the light due to the divergence angle of the exit beam of the simulator (as shown in Figure 1). So with the design of the present invention, this can be overcome effectively.

As shown in FIG. 4 , the temperature-controlled battery fixture 7 includes a vacuum pump 11 at the front and a water-cooled heat exchanger 16 at the rear. The concentrated solar cell 10 is adsorbed on the temperature-controlled cell fixture 7 during the test, and the adsorption force is provided by a vacuum pump 11 . The temperature-controlled battery fixture 7 uses a water-cooled heat exchanger 16 with a double-helix structure coil to obtain higher temperature uniformity. In addition, a temperature probe 13 is embedded to transmit the temperature data to the data processing system 9, and then the battery temperature is calculated by software, so as to obtain a more accurate volt-ampere characteristic curve.

In this embodiment, the simulated light source 2 is selected as a class A light source, the spectrum is AM1.5D, and the divergence angle is 3.4°.

The multiple of light concentration in this embodiment is determined according to the area of the outlet of the simulated light source 2 and the area of the battery sample. In this example, the more common 156×156mm simulated light source output light and 5×5mm III-V triple-junction battery are selected. As an example, a light concentration multiple of 385 times can be achieved. Refer to Figure 3 for the lens parameters of the designed condenser system.

Fig. 5 shows the workflow of the present invention. The light emitted by the simulated light source 2 enters the light concentrating system to focus, and irradiates the solar cell 10 to be tested. The optical power meter 8 moves to the spot position to collect light intensity data. The battery fixture 7 collects temperature data, and the data source table 6 collects I-V data through the test circuit, and collects them together into the data processing system. After calibration, the volt-ampere characteristic curve under standard conditions is obtained.

Fig. 6 is a simulated light spot analysis diagram of the embodiment of the present invention, and Fig. 7 is a light spot energy analysis diagram of the embodiment of the present invention.

Claims (7)

1. An indoor test device for concentrating photovoltaic solar cells with wide spectrum and large field of view, including an optical platform (1), a simulated light source (2), a battery fixture (7) and a test system. The light source (2) emits light, and the test system measures the photovoltaic characteristic curve of the solar cell (10) to be tested. The solar cell (10) to be tested is adsorbed on the battery fixture (7). The condensing system includes a focusing lens (3), a field lens (4) and a collimating lens (5) sequentially arranged in the optical path, and the light is focused on the solar cell (10) to be tested through the condensing system; The focusing lens (3) is a compound lens. In order to eliminate aberration, fluorite is used as a positive lens, and optical quartz glass is used as a negative lens, and the positive and negative lenses are not glued together. The focusing lens (3) is placed on a simulated light source ( 2) At the exit, the field lens (4) is placed at the focus of the focusing lens (3), and the focus of the collimating lens (5) coincides with the focus of the focusing lens (3); The focus of the focusing mirror (3) is measured using green light with a wavelength of 526.1nm, and the parameters are calculated by aberration analysis; the spectral range covers 300~1800nm. 2. The solar cell testing device according to claim 1, characterized in that the testing system includes an optical power meter (8) for measuring light intensity and a digital source meter (6) for measuring photovoltaic characteristic curves, and the obtained The data is transferred to the data processing system (9). 3. The solar battery testing device according to claim 1, characterized in that, the battery fixture (7) is a temperature-controlled battery fixture. 4. The solar cell testing device according to claim 3, characterized in that, the temperature-controlled cell fixture includes a vacuum pump (11) at the front and a water-cooled heat exchanger (16) at the rear. 5. The solar battery testing device according to claim 4, characterized in that the cold water used by the water-cooled heat exchanger (16) is provided by a water cooler (15), and the coil of the water-cooled heat exchanger (16) is double helix structure. 6. The solar battery testing device according to claim 4, characterized in that, the cooling water inlet and outlet of the water-cooled heat exchanger (16) and the surface of the battery fixture (7) are provided with a temperature probe (13), and the temperature The measurement data are transferred to the data processing system (9). 7. The solar cell testing device according to claim 1, characterized in that, the simulated light source (2) is a steady-state simulator of an AM1.5D filter.