CN103472430A - Solar simulator irradiation non-uniformity and instability test system - Google Patents

Abstract

A solar simulator irradiation non-uniformity and instability test system, including: four calibrated standard photovoltaic cells as light sensors, a data acquisition unit connected to the four standard photovoltaic cells, and a The computer to which the data acquisition unit is connected. One standard photovoltaic cell is fixed on the edge of the effective irradiated surface of the solar simulator under test, and the other three standard photovoltaic cells are arranged in three left and right adjacent equally divided cells on the effective irradiated surface of the solar simulator; Starting from the upper left corner of the effective irradiation surface of the solar simulator, a standard photovoltaic cell is manually moved sequentially with three cells as a unit without overlapping, covering all rows of the effective irradiation surface of the solar simulator. The signal detected by this system is processed to obtain the irradiance non-uniformity value and instability value of the solar simulator, and the grade evaluation is made according to the international standard IEC60904‐9:2007.

Description

Solar Simulator Irradiation Nonuniformity and Instability Test System

technical field

The invention relates to a detection device.

Background technique

The solar simulator is a device that simulates the spectrum and irradiance of natural sunlight. It is widely used in the electrical performance parameters and durability measurement of photovoltaic devices. According to the working mode, it can be divided into two categories: steady-state type and pulse type. The pulse type solar simulator is generally only used for the I-V characteristic measurement of photovoltaic devices, and the steady-state solar simulator can be used for the I-V characteristic measurement and durability measurement of photovoltaic devices. The level of the solar simulator used for the measurement of photovoltaic devices on the ground is evaluated according to the three indicators of spectral distribution, irradiance non-uniformity and irradiance instability.

As more and more solar simulators are put into use in the photovoltaic industry, the performance evaluation of solar simulators has become a hot research direction of current testing technology. Patent 201020577557.9 uses a standard photovoltaic cell as an illumination sensor to collect light, and measures the unevenness of irradiation by manually moving sequentially in the divided cells in the effective irradiation surface. The collected signal is sent to the computer after being converted by AD through a data collector. Using this device for testing cannot avoid the deviation caused by the change of each flash irradiance value of the pulse type solar simulator, which leads to inaccurate test results and cannot evaluate the unevenness index of the solar simulator well.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the prior art, and propose a test system for the unevenness and instability of solar simulator irradiation. The invention can more accurately test the unevenness and instability of solar simulator irradiation. On the basis of photoelectric signal conversion, high-precision and high-sampling-rate independent AD hardware, multiple standard photovoltaic cells are used as light sensors to collect synchronously The data make up for the influence of the solar simulator irradiation instability on the non-uniformity test at different time points. The test system is small in size, easy to carry, and suitable for different types of solar simulators.

In order to achieve the above object, the technical scheme adopted in the present invention is:

The test system of the present invention comprises:

Four calibrated standard photovoltaic cells, which are used as the light sensor of the test system of the present invention;

A data acquisition unit, which is connected with four standard photovoltaic cells, and performs AD conversion on the signals collected by the system;

A computer, which is connected to the data acquisition unit through a USB data cable, and provides data display and processing for the system;

This system is used to test the irradiance non-uniformity and instability value of the solar simulator, and obtain the performance level of this index.

The size of the standard photovoltaic cell is 2cm×2cm, and the material is polycrystalline silicon or monocrystalline silicon. The standard photovoltaic cell has been calibrated and has a stable calibration value. The standard photovoltaic cell is produced in accordance with the provisions of the international standard IEC60904-2:2007.

The data acquisition unit includes a four-channel independent AD data acquisition card and four high-precision standard resistors with a resistance value of 0.1 ohms; the four channels of the data acquisition card are in one-to-one correspondence with the high-precision standard resistors .

The data acquisition card has four channels, each channel includes positive and negative interfaces, and the positive and negative interfaces of each channel are respectively connected to two ends of a corresponding standard resistor. The data acquisition card is used to collect the voltage value at both ends of the resistance, and the collected voltage value signal is converted into a digital signal by the data acquisition card AD and then sent to the computer.

The data acquisition unit includes four input channels and one output channel.

The input channels of the data acquisition unit are connected to standard photovoltaic cells through high-frequency cables, and the four input channels are respectively connected to four standard photovoltaic cells. The output channel is connected to the computer through a high-speed USB data cable with a shielding ring.

The computer displays the data curves of the collected signals, and obtains the irradiance uniformity value and instability value of the solar simulator through data processing, and makes grade evaluation according to the international standard IEC60904-9:2007.

Working process of the present invention is:

After determining the size of the effective irradiation surface of the solar simulator under test, the effective irradiation surface is divided into several cells according to the IEC60904-9:2007 international standard. One of the standard photovoltaic cells is fixed on the edge of the effective irradiation surface of the solar simulator under test, and the remaining three standard photovoltaic cells are arranged in three left and right adjacent equal division cells of the effective irradiation surface of the solar simulator. Take the three standard photovoltaic cells to be moved as a whole, start from the upper left corner of the effective irradiation surface of the solar simulator, move from left to right in the first row of cells, and move them manually in a sequence of three cells without overlapping , after covering the cells in the first row, manually move the cells in the second row in the same order, and so on, to cover all the rows of the effective irradiation surface of the solar simulator. If the equally divided cells from left to right are not an integer multiple of three, one or two standard photovoltaic cells can be reduced when moving to the far right to ensure that all cells in the effective irradiation area of the solar simulator are just covered to avoid Multiple tests.

The current signal generated by the standard photovoltaic cell in the equally divided cells of the effective irradiation surface of each solar simulator, together with the current signal generated by the standard photovoltaic cell fixed at the edge of the effective irradiation surface of the solar simulator under test, is passed through the high The frequency cable is sent to the data acquisition unit.

After the standard precision resistance in the data acquisition unit is converted into a voltage signal, it is collected by the data acquisition card, and after being converted by AD, the digital signal is transmitted to the computer through the USB data line.

Through computer processing and analysis of data, the solar simulator's irradiance non-uniformity and instability are respectively obtained, and the performance grade evaluation of this index is made.

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

1. The present invention adopts a standard photovoltaic cell to be fixed on the edge of the effective irradiation surface of the tested solar simulator, and the other three standard photovoltaic cells are manually moved sequentially in the cells divided by the effective irradiation surface of the tested solar simulator. Measure the irradiance value. The irradiance values measured by the three standard photovoltaic cells are compared and corrected with the irradiance values measured by the standard photovoltaic cells fixed at the edge of the effective irradiated surface of the solar simulator under test, and the unevenness of the solar simulator is obtained. It avoids the impact of the instability of the light source on the non-uniformity test caused by the different irradiance values of the pulse-type solar simulator or the steady-state simulator as the test time point changes.

2. The present invention is not only applicable to pulse-type solar simulators, but also to steady-state solar simulators.

3. The present invention uses three standard photovoltaic cells to move simultaneously, which improves the test efficiency and simplifies the test process.

4. The present invention adopts four independent AD data acquisition units, realizes synchronous acquisition of four channels, and improves test accuracy.

5. The present invention adopts a data acquisition unit with a sampling frequency of up to 1M/s, which can increase the number of sampling points within a limited time period, increase the number of data samples collected in a unit time period, and improve the acquisition accuracy.

6. The present invention adopts high-precision standard resistors with stable performance, which improves the data conversion precision.

7. The computer used in the present invention can not only display data, but also automatically process data samples, judge parameter index levels according to calculation results, and automatically generate test reports, which effectively improves test efficiency and saves labor costs.

Description of drawings

Fig. 1 is a schematic structural view of the present invention, in which: No. C11 standard photovoltaic cell, No. C22 standard photovoltaic cell, No. C33 standard photovoltaic cell, and No. C44 standard photovoltaic cell;

Fig. 2 is a schematic diagram of the placement and movement sequence of four standard photovoltaic cells in the present invention;

Fig. 3 adopts the present invention to test the nonuniformity plane view of a certain type of pulsed solar simulator;

Fig. 4 is a curve chart of instability data of a certain type of pulsed solar simulator tested by the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, the solar simulator irradiation unevenness and instability testing system of the present invention includes: No. 1 standard photovoltaic cell C1, No. 2 standard photovoltaic cell C2, No. 3 standard photovoltaic cell C3, and No. 4 standard photovoltaic cell C4. Four standard photovoltaic cells C1, C2, C3, C4 are used as light sensors of the present invention. The size of the standard photovoltaic cell is 2cm×2cm, and the material is polycrystalline silicon or monocrystalline silicon. According to the international standard IEC60904-2:2007, the battery is packaged in an aluminum alloy shell and has a stable calibration value after the calibration test.

The No. 1 standard photovoltaic cell C1 is fixed at the edge of the effective irradiation surface of the solar simulator under test, and the No. 1 standard photovoltaic cell C1 is used as a reference for comparison of irradiance and correction of instability.

The No. 2 standard photovoltaic cell C2, the No. 3 standard photovoltaic cell C3 and the No. 4 standard photovoltaic cell C4 are arranged in three left and right adjacent equal division cells of the solar simulator irradiation surface, and the described No. Three standard photovoltaic cells are used to measure the irradiance value of the solar simulator. The moving method is: take three standard photovoltaic cells to be moved: the No. 2 standard photovoltaic cell C2, the No. 3 standard photovoltaic cell C3 and the No. 4 standard photovoltaic cell C4 as a whole, from the effective irradiation surface of the solar simulator Starting from the upper left corner, move from left to right in the first row of cells, using three cells as a unit, and manually move sequentially without overlapping. After covering the first row of cells, then move in the same order in the second row of cells Move manually, and so on, to cover all rows of the effective irradiation surface of the solar simulator. If the equally divided cells from left to right are not an integer multiple of three, one or two standard photovoltaic cells can be reduced when moving to the far right to ensure that all cells in the effective irradiation area of the solar simulator are just covered to avoid Multiple tests.

The invention also includes a data acquisition unit. The data acquisition unit includes a four-channel independent AD data acquisition card and four high-precision standard resistors R1, R2, R3, and R4 with a resistance value of 0.1 ohms; the four standard photovoltaic cells C1, C2, C3, and C4 Respectively through the corresponding channels of the data acquisition unit and the corresponding standard resistors R1, R2, R3 or R4 to form four closed-loop loops, the four closed-loop loops generate current under light conditions; The data acquisition card has four input channels, and each input channel includes two positive and negative interfaces. The positive and negative interfaces of each channel are respectively connected to the two ends of the corresponding standard resistors R1, R2, R3 or R4, which are used in the acquisition place. The voltage signals at both ends of the four 0.1 ohm high precision standard resistors R1, R2, R3 and R4 mentioned above. After the four voltage signals are converted into digital signals through the AD of the data acquisition card, they are transmitted to the computer through the output channel of the data acquisition unit through the USB data line.

The invention also includes a computer, which is connected with the data acquisition unit through a USB data line, and provides data display and processing for the system. The computer displays the data curves of the collected signals, obtains the irradiance non-uniformity value and instability value of the solar simulator through data processing, and judges the performance level of the indicators according to the international standard IEC60904-9:2007.

The working steps of this system to test the solar simulator are carried out according to the steps described in the international standard IEC60904-9:2007. The present invention uses standard photovoltaic cells as irradiance light sensors, and divides the effective irradiation surface into several test grids according to the size of the effective irradiation surface of the solar simulator. A standard photovoltaic cell is fixed on the edge of the effective irradiation surface as a reference cell, and the other three standard photovoltaic cells are manually moved to measure the irradiance values at different positions. Each standard photovoltaic cell collects the irradiance value of the solar simulator synchronously through four channels of the data acquisition unit, converts it into a digital signal through AD, and transmits it to the computer. It is processed by a computer, and compared with the reference battery, the irradiance correction calculation is performed, and the irradiance non-uniformity value of each test grid in the effective irradiated surface of the solar simulator is calculated.

1. Irradiation unevenness test

Example: The effective irradiation surface of a pulsed solar simulator is 200cm×100cm. Dividing this area by 64 gives 312.5 cm ² . Since this value is less than 400cm ² , the maximum size of a standard photovoltaic cell cannot exceed 312.5cm ² , and at least 64 squares must be divided into the effective irradiation surface. If it is divided into eight rows and nine columns with a total of 72 squares for testing, four standard photovoltaic cells are used as light sensors for measurement. One of them, as a reference cell, is placed at the edge of the effective irradiation surface. The other three pieces are used as mobile batteries, which are sequentially arranged in three left and right adjacent equally divided cells in the effective irradiation surface of the solar simulator. The three standard photovoltaic batteries to be moved are taken as a whole, starting from the upper left of the effective irradiation surface. Starting from the corner, from left to right, manually move three times in the first row of cells in a unit of three cells without overlapping. After covering the first row of cells, then manually move in the second row of cells in the same order , and so on, a total of 24 manual moves in sequence to ensure that all 72 cells in the effective irradiation surface of the solar simulator are just covered, as shown in Figure 2. The data acquisition unit synchronously collects the test signals of four standard photovoltaic cells and sends them to the computer for processing. The irradiance value collected by the solar simulator is corrected with the value collected by the reference battery, and the corrected irradiance value is obtained as the effective irradiance value of each test square.

The inhomogeneity matrix data of the pulsed solar simulator is shown in Table 1, and the inhomogeneity plane is shown in Fig. 3.

Table 1 Non-uniformity matrix

997.16 999.35 1015.84 1017.70 997.46 1007.32 1022.28 1029.79 1033.34 997.61 1001.21 1009.65 997.57 999.12 1009.78 1022.47 1029.55 1028.25 998.02 1003.58 999.74 1002.53 1001.12 1014.52 1028.04 1030.74 1027.98 997.18 1012.95 1002.75 998.25 1006.29 1014.97 1027.52 1026.35 1029.61 1006.26 999.91 1001.84 1004.94 1003.40 1019.13 1024.96 1028.35 1035.97 1003.73 1001.20 1004.91 1006.00 1009.46 1012.47 1024.50 1033.48 1035.45 997.66 1003.01 1007.24 1000.97 1011.50 1015.83 1025.33 1036.17 1030.86 998.19 1003.72 1008.81 999.88 1004.62 1017.16 1020.13 1029.58 1020.13

Irradiation unevenness is calculated using formula (1):

The maximum irradiance and minimum irradiance refer to the measured value of a standard photovoltaic cell at any specified point within the effective test plane.

2. Irradiation instability test

Example: For a certain pulsed solar simulator with an effective irradiated surface of 200cm×100cm, the instability is related to the irradiance change within the data collection time. In the previous non-uniformity test embodiment, the data collected by the standard photovoltaic cell located at the center point of the effective irradiation surface of the solar simulator, such as the fourth row and the fifth column, is analyzed and calculated, and the instability data curve is shown in Figure 4 shown.

According to the formula (2) to calculate the degree of instability.

The maximum irradiance and minimum irradiance here are determined by the use of the solar simulator. If it is a solar simulator for durability radiation measurement, the maximum irradiance and minimum irradiance refer to the irradiance value measured by the detector at any point in the test plane during the irradiation time period.

Claims (3)

1. a solar simulator irradiation nonuniformity and instability test macro, is characterized in that, described test macro comprises:

Four standard photovoltaic cells (C1, C2, C3, C4) through demarcating, as the optical sensor of described test macro;

A data collecting unit, four input channels of this data acquisition unit are connected with four standard photovoltaic cells (C1, C2, C3, C4), and the signal that described test macro is gathered carries out the AD conversion;

A computing machine, this computing machine is connected by the usb data line with data acquisition unit, to described test macro, provides data process and show.

2. solar simulator irradiation nonuniformity according to claim 1 and instability test macro, it is characterized in that, comprise a four-way independence AD data collecting card and four measuring resistances (R1, R2, R3, R4) that resistance is 0.1 ohm in described data acquisition unit; The positive and negative interface of each passage of described data collecting card connects respectively the two ends of corresponding measuring resistance.

3. solar simulator irradiation nonuniformity according to claim 1 and instability test macro, it is characterized in that, in described four standard photovoltaic cells, a standard photovoltaic cell (C1) is fixed on the edge of tested solar simulator effective irradiation face, in the adjacent decile cell in three left and right that its excess-three piece standard photovoltaic cell (C2, C3, C4) is arranged in solar simulator effective irradiation face successively; With three standard photovoltaic cells (C2, C3, C4), do as a whole, from the upper left corner of solar simulator effective irradiation face, from left to right in the first row cell, take three cells as a unit manual ordinal shift overlappingly not, after having covered the first row cell, then with same order, at the second row cell, manually move, the like, all row of covering solar simulator effective irradiation face.

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