Diode performance test method and device

Abstract

The invention relates to a diode performance test method and device. The diode performance test method comprises the following steps: carrying out at least one round of pressure impact test on a to-be-tested diode device; and after each round of pressure impact test, detecting whether the diode device is invalid, if the diode device is invalid, determining the compressive strength of the diode device according to the test parameters used in the previous round of pressure impact test, and stopping the next round of pressure impact test, and if the diode device is not invalid, adjusting the test parameters, and if the diode device is not invalid, adjusting the compressive strength of the diode device. The next round of pressure impact test is carried out based on the adjusted test parameters; wherein the pressure impact test comprises the step of applying impact to the diode device by using a heated stamping device. The pressure impact on the diode can be simulated, and the reliability and safety of the diode can be tested.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a diode performance testing method and device. Background Art

[0002] Under certain conditions, the shaded solar cell in the series branch of a photovoltaic module will be treated as a load and consume the energy generated by other illuminated solar cells. The shaded solar cell will heat up at this time, which is the hot spot effect. In practical applications, the hot spot effect is an important factor affecting the quality and safety of photovoltaic modules.

[0003] In order to prevent solar cells from being damaged by the hot spot effect, a bypass diode is usually connected in parallel between the positive and negative electrodes of the solar cell. The bypass diode can act as a bypass when a solar cell in a photovoltaic module cannot generate electricity due to the hot spot effect, allowing the photovoltaic module to continue to generate electricity. Therefore, the long-term reliability and safety of the bypass diode are crucial.

[0004] During the production process of diodes and photovoltaic modules, as well as during the use of diodes, there may be situations where the diodes are impacted, which will affect the safety and reliability of the diodes. Summary of the invention

[0005] Based on this, the present application provides a diode performance testing method and device for simulating the pressure shock on the diode and testing the reliability and safety of the diode.

[0006] In a first aspect, the present application provides a diode performance testing method, the diode performance testing method comprising:

[0007] Perform at least one round of pressure shock test on the diode device to be tested;

[0008] After each round of pressure shock test, check whether the diode device fails. If the diode device fails, determine the compressive strength of the diode device according to the test parameters used in the previous round of pressure shock test, and stop the next round of pressure shock test. If the diode device does not fail, adjust the test parameters, and perform the next round of pressure shock test based on the adjusted test parameters.

[0009] The pressure shock test includes: applying shock to the diode device using a heated stamping device.

[0010] In one embodiment, detecting whether a diode device fails includes:

[0011] Obtaining electrical performance parameters of diode devices;

[0012] Perform thermal runaway test on diode devices and obtain test results;

[0013] Determine whether the diode device is failed based on the electrical performance parameters and test results.

[0014] In one embodiment, determining whether a diode device is failed based on electrical performance parameters and a test junction includes:

[0015] If the diode device is determined to be failed based on the electrical performance parameters, or if the diode device is determined to be failed based on the test results, then the diode device is determined to be failed.

[0016] In one embodiment, the electrical performance parameters include the forward voltage drop V F , reverse breakdown voltage V B and reverse leakage current I R , the diode performance test method also includes:

[0017] Get the forward voltage drop V of the diode device before a round of pressure shock test F1 , and the forward voltage drop V of the diode device after a round of pressure shock test F2 ;

[0018] Obtain the reverse breakdown voltage V of the diode device before a round of pressure shock test B1 , and the reverse breakdown voltage V of the diode device after a round of pressure shock test B2 ;

[0019] Obtain the reverse leakage current I of the diode device before a round of pressure shock test R1 , and the reverse leakage current I of the diode device after a round of pressure shock test R2 ;

[0020] If V F1 and V F2 Does not satisfy |[(V F2 -V F1 ) / V F1 )]|≤10%, or, V B1 and V B2 Does not satisfy |[(V B2 -V B1 ) / V B1 )]|≤10%, or, I R1 and I R2 Not satisfied with I R2 / I R1 ≤2, it is determined that the diode device has failed.

[0021] In one embodiment, detecting whether a diode device fails further includes:

[0022] Conduct working simulation on diode devices;

[0023] Check whether the diode device is failed.

[0024] In one embodiment, performing an operation simulation on a diode device includes:

[0025] A reverse bias voltage is applied to the diode device; and / or, a forward rated current is passed through the diode device; and / or, a forward surge current is passed through the diode device; and / or, a reverse surge current is passed through the diode device.

[0026] In one embodiment, the test parameters include heating temperature, impact pressure, impact time, and impact speed, and the pressure impact test includes:

[0027] Heating the stamping device to a preset heating temperature;

[0028] The stamping device is controlled to continuously impact the diode device according to a preset impact pressure and a preset impact speed, and the duration is a preset impact time.

[0029] In one embodiment, adjusting the test parameters includes:

[0030] Increase at least one or more of the heating temperature, impact pressure, impact time and impact speed in a certain proportion.

[0031] In a second aspect, the present application also provides a diode performance testing device, comprising:

[0032] A failure detection device, used to detect whether the diode device to be tested has failed;

[0033] A stamping device, used to perform a pressure shock test on the diode device to be tested, the pressure shock test comprising applying a shock to the diode device using a heated stamping device;

[0034] A processing device, used for controlling the stamping device to perform at least one round of pressure shock test on the diode device to be tested;

[0035] The processing device is also used to control the failure detection device to detect whether the diode device has failed after each round of pressure shock test. If the diode device has failed, the compressive strength of the diode device is determined according to the test parameters used in the previous round of pressure shock test, and the next round of pressure shock test is stopped. If the diode device has not failed, the test parameters are adjusted, and the stamping device is controlled to perform the next round of pressure shock test based on the adjusted test parameters.

[0036] In one embodiment, the failure detection device includes a thermal runaway failure detection device and an electrical performance parameter failure detection device.

[0037] In one of the embodiments, the diode performance test device further comprises a limiting device for fixing the diode device to be tested, and the limiting device is also used to be electrically connected to the diode device to be tested;

[0038] The thermal runaway failure detection device comprises a power supply, which is electrically connected to the limit device.

[0039] In one embodiment, the punching device comprises:

[0040] Pressure rod;

[0041] A pressure head fixed at one end of the pressure rod;

[0042] A driving member, used for driving the pressure rod to move, thereby driving the pressure head to exert an impact on the diode device;

[0043] Heating element, used to heat the pressing rod and the pressing head.

[0044] The above-mentioned diode performance test method and device can simulate the situation where the diode device is subjected to pressure shock during actual production and use by impacting the diode device with a stamping device, and detect whether the diode device fails after each round of pressure shock test by performing at least one round of pressure shock test on the diode device. If the diode device fails, the compressive strength of the diode device is output, and the reliability and safety of the diode device are characterized by the compressive strength. If it does not fail, the pressure shock test is continued after adjusting the test parameters until the diode device fails. It can be seen that the present application simulates the pressure shock to which the diode device is subjected during actual production and use by the pressure shock test, and determines the compressive strength of the diode device by the provided diode performance test method, thereby realizing the evaluation of the reliability and safety of the diode device, so that the diode can be better applied according to the test results, which is conducive to improving the safety of photovoltaic modules. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] FIG. 1 is a side view of a module diode in the prior art.

[0046] FIG. 2 is a schematic diagram of the structure of a module diode in the prior art.

[0047] FIG. 3 is a schematic structural diagram of a junction box body in the prior art.

[0048] FIG. 4 is a schematic flow chart of a diode performance testing method provided in an embodiment of the present application.

[0049] FIG5 is a schematic diagram of a diode performance testing device provided in an embodiment of the present application.

[0050] FIG. 6 is another schematic diagram of a diode performance testing device provided in an embodiment of the present application.

[0051] Reference numerals

[0052] 10-diode device; 101-conductive sheet; 102-plastic package; 103-diode chip; 104-metal jumper; 105-positioning hole; 20-junction box body; 201-positioning column; 3-failure detection device; 30-electrical performance parameter failure detection device; 31-thermal runaway failure detection device; 4-diode device; 5-limiting device; 51-limiting member; 311-first power supply; 312-second power supply; 313-first current detection device; 314-second current detection device; 61-pressure rod; 62-pressure head; 621-first pressure head; 622-second pressure head; 63-driving member; 64-heating member; 641-third power supply; 71-temperature sensor; 72-temperature reading device; 73-pressure reading device; 65-sliding member; 8-bracket; 9-laboratory table. DETAILED DESCRIPTION

[0053] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0054] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0055] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0056] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0057] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0058] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0059] When a cell or a group of cells in a photovoltaic module is shaded or damaged, a hot spot effect may occur in the photovoltaic module. In practical applications, the hot spot effect is an important factor affecting the quality and safety of photovoltaic modules. The bypass diode in the junction box of the photovoltaic module is an important component to reduce the risk of fire caused by the hot spot effect, so the long-term reliability and safety of the bypass diode is crucial.

[0060] Figure 1 is a side view of a module diode in the prior art. Figure 2 is a schematic diagram of the structure of a module diode in the prior art. Figure 3 is a schematic diagram of the structure of a junction box body in the prior art.

[0061] In the process of diode production and photovoltaic module production, there will be situations where the diode is impacted. Referring to Figures 1 and 2, the module diode includes a conductive sheet 101, a plastic package 102, a diode chip 103, a metal jumper 104, etc. Since the structure of the diode itself is composed of different materials, the expansion coefficients of different materials are different. After experiencing high and low temperature cycles, the expansion and contraction of each material are different, so it will cause stress impact to the diode chip 103, so that the diode chip 103 has the risk of damage and failure due to stress impact. At the same time, referring to Figures 2 and 3, the photovoltaic module junction box includes a junction box body 20 and a module diode. The module diode is assembled with the junction box body 20 through a cold riveting process, and the four positioning holes 105 of the diode correspond to the four positioning columns 201 of the junction box body 20. In the photovoltaic module junction box assembly process, the cold riveting process will use a certain impact force to impact the conductive sheet 101 of the module diode and the positioning columns of the junction box body 20, thereby completing the assembly. This external force impact has the risk of damaging the diode chip 103. In addition, during the production of photovoltaic modules, the conductive sheet 101 of the module diode is connected to the bus bar by high-temperature welding. The welding process will impact the center of the conductive sheet 101 of the module diode under high temperature conditions, causing the diode chip 103 to be damaged and fail. The above situations will affect the safety and reliability of the module diode.

[0062] However, there is currently no method to test the strength, impact resistance, and stress resistance of diodes, making it impossible to evaluate the performance of diodes in this regard.

[0063] FIG. 4 is a schematic flow chart of a diode performance testing method provided in an embodiment of the present application.

[0064] Referring to FIG. 4 , an embodiment of the present application provides a diode performance testing method, the diode performance testing method comprising:

[0065] S100, performing at least one round of pressure shock test on the diode device to be tested;

[0066] S200, after each round of pressure shock test, detect whether the diode device fails. If the diode device fails, determine the compressive strength of the diode device according to the test parameters used in the previous round of pressure shock test, and stop the next round of pressure shock test. If the diode device does not fail, adjust the test parameters, and perform the next round of pressure shock test based on the adjusted test parameters;

[0067] The pressure shock test includes: applying a shock to the diode device using a heated stamping device. Applying a shock may mean that the stamping device applies a shock pressure to the diode device, the shock pressure is greater than or equal to 500N, and the contact area between the stamping device and the diode device is within a range of 10mm2 -120mm 2 If the impact pressure is less than the compressive strength of the diode device, the diode device will not fail. If the impact pressure is greater than the compressive strength of the diode device, the diode device will fail.

[0068] Based on this, by impacting the diode device with a punching device, the situation in which the diode device is subjected to pressure shock during actual production and use can be simulated, and since the situation in which the diode device is impacted usually occurs at a certain temperature, using a heated punching device to impact the diode can better simulate the actual situation of the diode device when it is subjected to pressure shock, which is conducive to obtaining a more reliable compressive strength of the diode device. By performing at least one round of pressure shock test on the diode device and detecting whether the diode device fails after each round of pressure shock test, the performance of the diode under continuous pressure shock can be observed while simulating the diode device being subjected to pressure shock. After each round of pressure shock test, if the diode device fails, the compressive strength of the diode device is output, and the reliability and safety of the diode device are characterized by the compressive strength. If it does not fail, the pressure shock test is continued after adjusting the test parameters until the diode device fails. It can be seen that the embodiment of the present application simulates the pressure shock received by the diode device during actual production and use through the pressure shock test, and determines the compressive strength of the diode device through the provided diode performance test method, so as to realize the evaluation of the reliability and safety of the diode device, so that the diode can be better applied according to the test results, which is conducive to improving the safety of the photovoltaic module.

[0069] When failure of the diode device is detected after the first round of pressure shock test, the test is terminated directly without outputting the compressive strength of the diode device.

[0070] In some examples, the pressure shock actually experienced by the diode device includes external pressure shock (hereinafter referred to as external force shock) and internal stress shock. When performing performance testing on the diode device, pressure shock tests can be performed separately on the external force shock and internal stress shock experienced by the diode device to simulate the external force shock and internal stress shock experienced by the diode device, and whether the diode device fails under the external force shock simulation and the internal stress shock simulation can be detected respectively to obtain different compressive strengths.

[0071] Further, referring to Figures 1 and 2, there are mainly two types of external force impacts on the diode device. One is the external force applied to the conductive sheet 101 of the diode device and the positioning columns at the four corners of the junction box body 20 when assembling the photovoltaic module junction box. The other is the external force applied to the conductive sheet 101 of the diode device during welding. Therefore, when performing a simulation test on the external force impact on the diode device, a heated stamping device can be used to apply an impact to the center position of the conductive sheet 101 of the diode device. The internal stress on the diode device is mainly due to the different materials of the conductive sheet 101, the plastic package 102, the diode chip 103 and the metal jumper 104 in the diode device. For example, the material of the diode chip 103 is usually silicon, the material of the conductive sheet 101 and the metal jumper 104 is usually copper, and the material of the plastic package 102 is usually epoxy resin. The thermal expansion coefficients of these three bulk materials are different, and internal stress will be generated in the plastic package 102 during high and low temperature cycles. Therefore, when conducting a simulation test on the internal stress impact on the diode device, a heated stamping device can be used to apply an impact to the center of the plastic package 102 of the diode device.

[0072] In some examples, the diode device may be a module diode or a module diode installed in a photovoltaic module junction box. The specific determination may be based on actual test requirements, and the embodiments of the present application are not limited to this.

[0073] As a possible implementation method, detecting whether a diode device is failed includes:

[0074] Obtaining electrical performance parameters of diode devices;

[0075] Perform thermal runaway test on diode devices and obtain test results;

[0076] Determine whether the diode device is failed based on the electrical performance parameters and test results.

[0077] Based on this, after each round of pressure shock test, when detecting whether the diode device has failed, an electrical performance test can be performed on the diode device to obtain the electrical performance parameters of the diode device, and a thermal runaway test can be performed on the diode device to obtain the test results of the thermal runaway test. Then, based on the obtained electrical performance parameters and thermal runaway test results, it is judged whether the diode device has failed after each round of pressure shock test, and the electrical performance parameters and thermal runaway test results are used to characterize the changes in the electrical performance of the diode device after undergoing pressure shock simulation.

[0078] Exemplarily, the test results of the thermal runaway test include the thermal runaway test passing and the thermal runaway test failing. Furthermore, the thermal runaway test of the diode device may include: passing the forward rated current (IF) to the diode device to be tested, and after a period of time, switching to the reverse voltage, observing the reverse leakage state of the diode device to be tested, if it is in a decreasing state, the thermal runaway test passes, otherwise the thermal runaway test fails. Among them, the forward rated current IF is the calibration value of the diode device to be tested, and the reverse voltage is based on the open circuit voltage V of the photovoltaic module applicable to the diode to be tested. oc The voltage value is randomly selected, and the reverse voltage is at least the open circuit voltage V of the photovoltaic module applicable to the diode to be tested. oc For the same diode device, the reverse voltage selected for each thermal runaway test is the same voltage value.

[0079] Exemplarily, before performing the first pressure shock test on a diode device, an electrical performance test and a thermal runaway test can be performed on the diode device to be tested. Whether the diode device to be tested is intact can be judged based on the electrical performance parameters and thermal runaway test results before the first pressure shock test. If the electrical performance parameters of the diode device to be tested before the first pressure shock test are within the normal range and the thermal runaway test passes, the pressure shock test can be performed on the diode device; otherwise, it indicates that the diode device to be tested is damaged and no pressure shock test is performed.

[0080] In some examples, determining whether a diode device is failed based on electrical performance parameters and a test junction includes:

[0081] If the diode device is determined to be failed based on the electrical performance parameters, or if the diode device is determined to be failed based on the test results, then the diode device is determined to be failed.

[0082] Based on this, after each round of pressure shock test, the diode device is subjected to electrical performance test and thermal runaway test. If one of the electrical performance parameters and thermal runaway test results of the diode device fails, the diode device is judged to have failed, and the performance test of the diode device is terminated. The compressive strength of the diode device is determined based on the test parameters used in the previous round of pressure shock test.

[0083] Furthermore, the electrical performance parameters may include the forward voltage drop V F , reverse breakdown voltage V B and reverse leakage current I R , the diode performance test method also includes:

[0084] Get the forward voltage drop V of the diode device before a round of pressure shock test F1 , and the forward voltage drop V of the diode device after a round of pressure shock testF2 ;

[0085] Obtain the reverse breakdown voltage V of the diode device before a round of pressure shock test B1 , and the reverse breakdown voltage V of the diode device after a round of pressure shock test B2 ;

[0086] Obtain the reverse leakage current I of the diode device before a round of pressure shock test R1 , and the reverse leakage current I of the diode device after a round of pressure shock test R2 ;

[0087] If V F1 and V F2 Does not satisfy |[(V F2 -V F1 ) / V F1 )]|≤10%, or, V B1 and V B2 Does not satisfy |[(V B2 -V B1 ) / V B1 )]|≤10%, or, I R1 and I R2 Not satisfied with I R2 / I R1 ≤2, it is determined that the diode device has failed.

[0088] Among them, the forward voltage drop V F , reverse breakdown voltage V B and reverse leakage current I R It can be used as an electrical performance parameter to evaluate the forward conduction capability and performance stability of the diode device. When performing a performance test on the diode device, the electrical performance parameters can be compared to determine whether the electrical performance parameters are invalid, thereby determining whether the diode device is invalid. Furthermore, before a round of pressure shock test, an electrical performance test can be performed on the diode device to obtain the forward voltage drop V of the diode device before a round of pressure shock test. F1 , reverse breakdown voltage V B1 and reverse leakage current I R1 After a round of pressure shock test, the diode device is tested for electrical performance again to obtain the forward voltage drop V of the diode device after a round of pressure shock test. F2 , reverse breakdown voltage V B2 and reverse leakage current I R2 , compared with the forward voltage drop V F1 and forward voltage drop V F2 , reverse breakdown voltage V B1 and reverse breakdown voltage VB2 , reverse leakage current I R1 and reverse leakage current I R2 , and satisfy |[(V F2 -V F1 ) / V F1 )]|≤10%,|[(V B2 -V B1 ) / V B1 )]|≤10%,I R2 / I R1 ≤2, the electrical performance test is considered to have passed. Otherwise, if |[(V F2 -V F1 ) / V F1 )]|≤10%,|[(V B2 -V B1 ) / V B1 )]|≤10%,I R2 / I R1 If any one of the three criteria is not met, the electrical performance test is considered to have failed, which also means that the diode test has failed.

[0089] It should be noted that between two rounds of pressure shock tests, only one electrical performance test and thermal runaway test is required for the diode device. For the previous round of pressure shock test, the electrical performance parameters obtained from this electrical performance test are the electrical performance parameters obtained after the pressure shock test. For the next round of pressure shock test, the electrical performance parameters obtained from this electrical performance test are the electrical performance parameters obtained before the pressure shock test.

[0090] As a possible implementation method, detecting whether a diode device is failed also includes:

[0091] Conduct working simulation on diode devices;

[0092] Check whether the diode device is failed.

[0093] Based on this, if the test requirement is a standard test requirement, at least one round of pressure shock test can be performed on the diode device to be tested, and after each round of pressure shock test, it is detected whether the diode device has failed; if the test requirement is more stringent, at least one round of pressure shock test and at least one round of work simulation can be performed on the diode device to be tested, and after each round of pressure shock test and each round of work simulation, it is detected whether the diode device has failed, so that the diode performance test method provided in the embodiment of the present application can meet different test requirements and has better applicability.

[0094] In specific implementation, if the test requirements are standard test requirements, the diode performance test method may include: first performing an electrical performance test and a thermal runaway test, judging whether the diode device to be tested is intact based on the obtained electrical performance parameters and thermal runaway test results; if it is intact, performing a round of pressure shock test, and then performing an electrical performance test and a thermal runaway test again; determining whether the diode device has failed based on the thermal runaway test results and the electrical performance parameters before and after the pressure shock test; if it has failed, stopping the test; if it has not failed, adjusting the test parameters and performing the next round of pressure shock test based on the adjusted test parameters; and detecting whether the diode device has failed after each round of pressure shock test; if it has failed, stopping the test, and determining the compressive strength of the diode device based on the test parameters used in the previous round of pressure shock test; if it has not failed, continuing to adjust the test parameters and performing the next round of pressure shock test based on the adjusted test parameters until the diode test fails.

[0095] In specific implementation, if the test requirements are standard test requirements, the diode performance test method may include: first performing an electrical performance test and a thermal runaway test, judging whether the diode device to be tested is intact based on the obtained electrical performance parameters and the thermal runaway test results; if it is intact, performing a round of pressure shock test and working simulation on the diode, and then performing an electrical performance test and a thermal runaway test again; determining whether the diode device has failed based on the thermal runaway test results and the electrical performance parameters before and after the pressure shock test; if it has failed, stopping the test; if it has not failed, adjusting the test parameters and performing the next round of pressure shock test and working simulation based on the adjusted test parameters; and detecting whether the diode device has failed after each round of pressure shock test and working simulation; if it has failed, stopping the test, and determining the compressive strength of the diode device based on the test parameters used in the previous round of pressure shock test; if it has not failed, continuing to adjust the test parameters and performing the next round of pressure shock test and working simulation based on the adjusted test parameters until the diode test fails.

[0096] Exemplarily, the working simulation may be performed before or after the pressure shock test.

[0097] In some examples, performing an operation simulation on a diode device may include:

[0098] A reverse bias voltage is applied to the diode device; and / or, a forward rated current is passed through the diode device; and / or, a forward surge current is passed through the diode device; and / or, a reverse surge current is passed through the diode device.

[0099] Based on this, when the test requirements are relatively strict and it is necessary to perform a working simulation on the diode device, at least one or more of the following can be selected from applying a reverse bias voltage to the diode device, passing a forward rated current to the diode device, passing a forward surge current to the diode device, and passing a reverse surge current to the diode device as a working simulation of the diode device, so as to more comprehensively simulate various working conditions that may be encountered when the diode device is actually working, and then detect whether the diode device fails through a pressure shock test and an electrical performance test and a thermal runaway test after the working simulation, which is conducive to obtaining more accurate test results. Among them, the reverse bias voltage is the calibrated value of the diode device to be tested. How to select the working simulation can be determined according to the actual test requirements, and the embodiments of the present application are not limited to this.

[0100] Exemplarily, before a round of pressure shock test is performed on the diode device, any one or more of the following can be selected from applying a reverse bias voltage to the diode device, passing a forward rated current through the diode device, passing a forward surge current through the diode device, and passing a reverse surge current through the diode device to simulate the operation of the diode device, and / or, after a round of pressure shock test is performed on the diode device, any one or more of the following can be selected from applying a reverse bias voltage to the diode device, passing a forward rated current through the diode device, passing a forward surge current through the diode device, and passing a reverse surge current through the diode device to simulate the operation of the diode device.

[0101] As a possible implementation method, the test parameters include heating temperature, impact pressure, impact time, and impact speed. The pressure impact test includes:

[0102] Heating the stamping device to a preset heating temperature;

[0103] The stamping device is controlled to continuously impact the diode device according to a preset impact pressure and a preset impact speed, and the duration is a preset impact time.

[0104] Based on this, the parameters of the pressure shock test can be limited by heating temperature, shock pressure, shock time, and shock speed. When performing a pressure shock test on a diode device, the stamping device can be first heated to a preset heating temperature, and the shock pressure, shock speed, and shock time of the stamping device can be set. Then, the stamping device is controlled to continuously apply pressure to the diode device according to the set shock pressure, and the duration is the set shock time. The diode device is continuously pressed down at the set shock speed within the set shock time to simulate the pressure shock to the diode device under certain temperature conditions. Then, the diode device is subjected to electrical performance tests and thermal runaway tests to detect whether the diode device has failed.

[0105] Among them, taking the example of the stamping device applying impact to the conductive sheet 101 of the diode device, the impact time refers to the time when the stamping device is in contact with the conductive sheet 101 of the diode device. During this period of time, the stamping device continues to press down the conductive sheet 101 of the diode device according to the preset impact pressure and impact speed; taking the example of the stamping device applying pressure to the plastic package 102 of the diode device, the impact time refers to the time when the stamping device is in contact with the plastic package 102 of the diode device. During this period of time, the stamping device continues to press down the plastic package 102 of the diode device according to the preset impact pressure and impact speed.

[0106] It should be noted that after each round of pressure shock test, if the diode device fails, the compressive strength of the diode device determined according to the test parameters used in the previous round of pressure shock test mainly includes the shock pressure used in the previous round of pressure shock test, and may also include the heating temperature, shock time and shock speed used in the previous round of pressure shock test.

[0107] In some examples, test parameters are adjusted, including:

[0108] Increase at least one or more of the heating temperature, impact pressure, impact time and impact speed in a certain proportion.

[0109] Based on this, when adjusting the test parameters, at least one or more of the heating temperature, impact pressure, impact time and impact speed can be increased in a certain proportion according to the actual test requirements, so as to achieve variable control when adjusting the test parameters, which is conducive to improving the accuracy of the test results.

[0110] Among them, when presetting the test parameters for the first pressure shock test, the heating temperature, shock pressure, shock time and shock speed can be set in any order. When adjusting the test parameters in the subsequent pressure shock test, at least one or more of the heating temperature, shock pressure, shock time and shock speed can be adjusted in any order. The embodiments of the present application are not limited to this.

[0111] For example, when the test requirement is a standard test requirement, the adjustment range of the heating temperature can be [25, 400] ° C, the adjustment range of the impact pressure can be (0, 5000] N, the adjustment range of the impact time can be (0, 10] s, and the adjustment range of the impact speed can be (0, 20] mm / min; when the test requirement is more stringent, the adjustment range of the heating temperature can be [25, 460] ° C, the adjustment range of the impact pressure can be (0, 5750] N, the adjustment range of the impact time can be (0, 11.5] s, and the adjustment range of the impact speed can be (0, 23] mm / min; wherein the adjustment range refers to the test parameters preset in the first pressure impact test and the value range of the test parameters after each adjustment of the test parameters.

[0112] For example, when the test requirement is a standard test requirement or the test requirement is relatively strict, the first preset heating temperature can be 25°C, 45°C or 60°C, etc., and each time the test parameters are adjusted, the heating temperature can be controlled to increase in units of 20°C, 25°C or 30°C, etc.; the first preset impact pressure can be 100N, 500N or 1000N, etc., and each time the test parameters are adjusted, the impact pressure can be controlled to increase in units of 100N, 200N or 300N; the first preset impact time can be 2s, 3s or 4s, etc., and each time the test parameters are adjusted, the impact time can be controlled to increase in units of 1s, 2s or 3s; the first preset impact speed can be 1mm / min, 2mm / min or 3mm / min, etc., and each time the test parameters are adjusted, the impact speed can be controlled to increase in units of 1mm / min, 2mm / min or 4mm / min. This is just an example and is not specifically limited.

[0113] For another example, when the test requirements are more stringent, the first preset heating temperature may be 200° C., 250° C., or 300° C., etc. These are merely examples and are not specifically limited.

[0114] It should be noted that when the pressure shock test is to simulate the internal stress shock to the diode device, when the stamping device applies shock to the plastic package 102 of the diode device, the heating temperature can be adjusted in the range of [25,75]°C to prevent the heated stamping device from damaging the plastic package 102 of the diode device due to excessive heating temperature when contacting the plastic package 102 of the diode device.

[0115] Fig. 5 is a schematic diagram of a diode performance test device provided in an embodiment of the present application. Fig. 6 is another schematic diagram of a diode performance test device provided in an embodiment of the present application.

[0116] 5 and 6 , an embodiment of the present application further provides a diode performance testing device, including: a failure detection device 3, used to detect whether a diode device 4 to be tested has failed; a stamping device, used to perform a pressure shock test on the diode device 4 to be tested, the pressure shock test including applying shock to the diode device 4 using a heated stamping device; a processing device (not shown in the figure), used to control the stamping device to perform at least one round of pressure shock test on the diode device 4 to be tested; the processing device is also used to control the failure detection device 3 to detect whether the diode device 4 has failed after each round of pressure shock test; if the diode device 4 has failed, the compressive strength of the diode device 4 is determined according to the test parameters used in the previous round of pressure shock test, and the next round of pressure shock test is stopped; if the diode device 4 has not failed, the test parameters are adjusted, and the stamping device is controlled to perform the next round of pressure shock test based on the adjusted test parameters.

[0117] Based on this, in combination with FIG. 5 and FIG. 6 , the diode device 4 can be impacted by a punching device to simulate the situation where the diode device 4 is subjected to pressure impact during actual production and use. Since the impact on the diode device 4 usually occurs at a certain temperature, the use of a heated punching device to impact the diode can better simulate the actual situation of the diode device 4 when it is subjected to pressure impact, which is conducive to obtaining a more reliable compressive strength of the diode device 4. The punching device is controlled by the processing device to perform at least one round of pressure impact test on the diode device 4, and the failure detection device 3 is controlled to detect whether the diode device 4 fails after each round of pressure impact test. While simulating the diode device 4 being subjected to pressure impact, the performance of the diode under continuous pressure impact can be observed. After each round of pressure impact test, if the diode device 4 fails, the compressive strength of the diode device 4 is output, and the compressive strength is used to characterize the reliability and safety of the diode device 4. If it does not fail, the pressure impact test is continued after adjusting the test parameters until the diode device 4 fails. It can be seen that the embodiment of the present application can perform a pressure shock test on the diode device 4 through a stamping device, simulate the pressure shock to which the diode device 4 is subjected during actual production and use, and detect whether the diode device 4 has failed through a failure detection device 3, and finally determine the compressive strength of the diode device 4, thereby realizing an evaluation of the reliability and safety of the diode device 4, so that the diode can be better applied according to the test results, which is beneficial to improving the safety of photovoltaic modules.

[0118] Exemplarily, the processing device may be a processor, a host computer, etc., which are only examples and are not specifically limited. In addition, the functions of the processing device may also be performed manually.

[0119] As a possible implementation, as shown in FIG5 and FIG6, the failure detection device 3 may include a thermal runaway failure detection device 31 and an electrical performance parameter failure detection device 303. Based on this, the thermal runaway device failure detection device 3 may be used to perform a thermal runaway test on the diode device 4 to obtain the thermal runaway test result of the diode device 4, and the electrical performance parameter failure detection device 303 may be used to obtain the electrical performance parameters of the diode device 4, so that it can be determined whether the diode device 4 fails after a round of pressure shock test based on the thermal runaway test result and the electrical performance parameters. In addition, the thermal runaway failure detection device 31 and the electrical performance parameter failure detection device 303 may be used to detect whether the diode device 4 is intact before the first round of pressure shock test.

[0120] Exemplarily, as shown in FIG. 5 and FIG. 6 , the electrical performance parameter failure detection device 303 may be a diode electrical performance testing device. When performing an electrical performance test on the diode device 4 , the diode electrical performance testing device is turned on to perform an electrical performance test on the diode device 4 to obtain electrical performance parameters of the diode device 4 .

[0121] In some examples, as shown in FIG. 5 and FIG. 6 , the diode performance test device further includes a limit device 5 for fixing the diode device 4 to be tested, and the limit device 5 is also used to be electrically connected to the diode device 4 to be tested; the thermal runaway failure detection device 31 includes a power supply, and the power supply is electrically connected to the limit device 5. Based on this, the limit device 5 can fix the diode device 4 to be tested in a predetermined position, and the power supply can be electrically connected to the diode device 4 to be tested through the limit device 5, so that the thermal runaway test of the diode device 4 can be realized. At the same time, the power supply is directly connected to the limit device 5, and then electrically connected to the diode to be tested through the limit device 5. When testing different diode devices 4, there is no need to connect the power supply and the diode device 4 to be tested every time, and only the limit device 5 and the diode device 4 need to be connected.

[0122] Exemplarily, as shown in FIG. 5 and FIG. 6 , the limiting device 5 may include two limiting members 51 , which may respectively fix opposite ends of the diode device 4 to be tested and respectively realize electrical connection with the two conductive sheets 101 of the diode device 4 .

[0123] Exemplarily, as shown in Fig. 5 and Fig. 6, the power supply may include a first power supply 311 and a second power supply 312, wherein the positive and negative electrodes of the first power supply 311 are electrically connected to the two stoppers 51, respectively, and the positive and negative electrodes of the second power supply 312 are electrically connected to the two stoppers 51, respectively. The first power supply 311 has a continuous constant current mode and a single-point current mode, and can provide a constant forward current and a forward pulse current for the diode device 4 to be tested, and the second power supply 312 has a continuous constant voltage mode and a single-point current mode, and can provide a constant reverse voltage and a reverse pulse current for the diode device 4 to be tested. The first power supply 311 and the second power supply 312 can simulate the working environment of the diode device 4. Furthermore, since the diode device 4 has the characteristics of forward conduction and reverse cutoff, when the photovoltaic module has a hot spot effect, the diode device 4 is in a forward conduction state, and a forward current can be passed through the diode device 4 through the first power supply 311 to simulate the working environment of the diode when it is forward conducted; when the photovoltaic module does not have a hot spot effect, the diode is in a reverse cutoff state, and a reverse voltage can be passed through the diode device 4 through the second power supply 312 to simulate the working environment of the diode when it is reverse cutoff.

[0124] Exemplarily, as shown in FIG. 5 and FIG. 6 , the diode electrical performance test device is electrically connected to the two stoppers 51 , and the diode electrical performance test device, the first power supply 311 , and the second power supply 312 may be connected in parallel with each other.

[0125] Exemplarily, as shown in Figures 5 and 6, the thermal runaway failure detection device 31 may also include a first current detection device 313 and a second current detection device 314, the first current detection device 313 is electrically connected to the first power supply 311, and is used to detect the current value flowing out of the first power supply 311, and the second current detection device 314 is electrically connected to the second power supply 312, and is used to detect the current value flowing out of the second power supply 312.

[0126] In specific implementation, the thermal runaway test of the diode device 4 may include: turning on the first power supply 311 at a preset temperature, passing the forward rated current IF to the diode device 4 to be tested, and after 1 hour, disconnecting the first power supply 311 within 3ms, turning on the second power supply 312, applying a reverse voltage to the diode device 4 to be tested, and observing the reverse leakage state of the diode device 4 to be tested by the second current detection device 314. If it is in a decreasing state, the diode device 4 passes the thermal runaway test, otherwise the thermal runaway test fails. The preset temperature during the thermal runaway test can be room temperature or a higher temperature, such as 60°C, 85°C or 100°C, etc., which is only used as an example here and is not specifically limited.

[0127] In addition, the first power supply 311 and the second power supply 312 can also be used to simulate the operation of the diode device 4. In specific implementation, applying a reverse bias voltage to the diode device 4 may include: turning on the continuous constant voltage mode of the second power supply 312 at room temperature, applying a reverse bias voltage to the diode device 4 for 1 hour; passing a forward rated current to the diode device 4 may include: turning on the continuous constant current mode of the first power supply 311 at room temperature, passing a forward rated current to the diode device 4 for 1 hour; passing a forward surge current to the diode device 4 may include: turning on the single-point current mode of the first power supply 311 at room temperature, passing a sinusoidal half-wave current with a peak current of 600A and a pulse width of 8.3ms to the diode device 4; passing a reverse surge current to the diode device 4 may include: turning on the single-point current mode of the second power supply 312 at room temperature, passing a reverse surge current with a peak current of 4A and a pulse width of 10μs to the diode device 4.

[0128] As a possible implementation, as shown in FIG5 and FIG6, the stamping device includes: a pressure rod 61; a pressure head 62 fixed at one end of the pressure rod 61; a driving member 63, which is used to drive the pressure rod 61 to move, thereby driving the pressure head 62 to apply impact to the diode device 4; and a heating member 64, which is used to heat the pressure rod 61 and the pressure head 62. Based on this, when the pressure impact test is performed on the diode device 4, the pressure rod 61 can be driven to move by the driving member 63, thereby driving the pressure head 62 fixed at one end of the pressure rod 61 to move, so that the pressure head 62 can contact with the diode device 4 and apply impact to the diode device 4 under the drive of the driving member 63. At the same time, the pressure rod 61 and the pressure head 62 can impact the diode device 4 at a certain heating temperature under the heating action of the heating member 64.

[0129] Exemplarily, as shown in FIG5 and FIG6, the pressure head 62 includes a first pressure head 621 and a second pressure head 622, and the first pressure head 621 includes two sub-pressure heads 62 (not shown in the figure). Referring to FIG5, when the pressure shock test simulates the external force impact on the diode device 4, the pressure head 62 can be the first pressure head 621, and the two sub-pressure heads 62 respectively press down the center position of the two conductive sheets 101 of the diode device 4; referring to FIG6, when the pressure shock test simulates the internal stress impact on the diode device 4, the pressure head 62 can be the second pressure head 622, and the second pressure head 622 presses down the center position of the plastic package 102 of the diode device 4.

[0130] Exemplarily, as shown in FIG. 5 and FIG. 6 , the heating element 64 may include a third power source 641 , which is electrically connected to the pressure rod 61 and may provide current to the pressure rod 61 , so that the temperature of the pressure rod 61 and the pressure head 62 rises.

[0131] In addition, if the preset temperature during the thermal runaway test is a higher temperature than the room temperature, the heating element 64 can also heat the pressure rod 61 and the pressure head 62 to the preset temperature to ensure the normal conduct of the thermal runaway test. In specific implementation, the pressure head 62 is in contact with the diode device 4, and the pressure rod 61 and the pressure head 62 are heated to the preset temperature by the heating element 64, and the thermal runaway test is performed at the preset temperature.

[0132] Exemplarily, as shown in Figures 5 and 6, the diode performance testing device may also include a temperature sensor 71 and a temperature reading device 72 connected to each other. The temperature sensor 71 is also connected to the pressure head 62 to monitor the temperature at the pressure head 62. The temperature reading device 72 obtains the temperature value at the pressure head 62 by reading the temperature monitored by the temperature sensor 71.

[0133] Exemplarily, as shown in Fig. 5 and Fig. 6, the diode performance test device may further include a pressure reading device 73, which may be connected to the diode device 4 to read the pressure applied to the diode device 4. In a specific implementation, the pressure reading device 73 may be connected to the driver 63 to read the pressure data at the driver 63, and the pressure data at the driver 63 may be used to represent the pressure applied to the diode device 4.

[0134] In specific implementation, when performing a pressure shock test, heating the stamping device to a preset heating temperature may include: controlling the current of the third power supply 641, and obtaining the temperature value at the pressure head 62 through the temperature sensor 71 and the temperature reading device 72, and heating the temperature at the pressure head 62 to the preset heating temperature; controlling the stamping device to continuously apply shock to the diode device 4 according to a preset shock pressure and a preset shock speed, and the duration is a preset shock time, which may include: controlling the pressure at the pressure head 62 through the driving member 63, and reading the pressure value through the pressure reading device 73, and adjusting the pressure at the pressure head 62 to the preset shock pressure; controlling the duration of the downward pressing of the pressure rod 61 and the pressure head 62 to the preset shock time and the downward pressing speed to the preset shock speed through the driving member 63, and then driving the pressure rod 61 through the driving member 63, driving the pressure head 62 to continuously impact the diode device 4 according to the preset shock pressure and the preset shock speed within the preset shock time.

[0135] Exemplarily, as shown in Figures 5 and 6, the stamping device may also include a sliding member 65 fixedly mounted on the outer periphery of the pressure rod 61, and the sliding member 65 is connected to the driving member 63. When performing a pressure impact test, the sliding member 65 is driven by the driving member 63 to move, driving the pressure rod 61 and the pressure head 62 to move, so that the pressure head 62 can contact the diode device 4 and apply an impact to the diode device 4 under the drive of the driving member 63. At the same time, the pressure rod 61 and the pressure head 62 can impact the diode device 4 at a certain heating temperature under the heating action of the heating member 64.

[0136] Exemplarily, the driving member 63 may include a cylinder, a hydraulic cylinder, or a motor, etc., which are only given as examples and are not specifically limited.

[0137] 5 and 6 , the diode performance test device may further include a bracket 8 , which may at least be used to fix and press the rod 61 and the pressure head 62 . When the impact device further includes a sliding member 65 , the bracket 8 may also be used to fix the sliding member 65 .

[0138] Exemplarily, as shown in FIG5 and FIG6, the diode performance test device can be placed on a horizontal experimental table 9. The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0139] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A diode performance testing method, characterized in that: The diode performance testing method comprises: Perform at least one round of pressure shock test on the diode device to be tested; After each round of pressure shock test, detect whether the diode device fails. If the diode device fails, determine the compressive strength of the diode device according to the test parameters used in the previous round of pressure shock test, and stop the next round of pressure shock test. If the diode device does not fail, adjust the test parameters, and perform the next round of pressure shock test based on the adjusted test parameters; Wherein, the pressure shock test comprises: applying shock to the diode device by using a heated stamping device.

2. The diode performance testing method according to claim 1, characterized in that: The detecting whether the diode device fails comprises: Obtaining electrical performance parameters of the diode device; Performing a thermal runaway test on the diode device to obtain a test result; Determine whether the diode device fails according to the electrical performance parameter and the test result.

3. The diode performance testing method according to claim 2, characterized in that: Determining whether the diode device fails according to the electrical performance parameter and the test node includes: If it is determined that the diode device has failed based on the electrical performance parameter, or if it is determined that the diode device has failed based on the test result, then it is determined that the diode device has failed.

4. The diode performance testing method according to claim 2, characterized in that: The electrical performance parameters include forward voltage drop V F , reverse breakdown voltage V B and reverse leakage current I R , the diode performance testing method further includes: Obtain the forward voltage drop V of the diode device before a round of pressure shock test F1 , and the forward voltage drop V of the diode device after a round of pressure shock test F2 ; Obtain the reverse breakdown voltage V of the diode device before a round of pressure shock test B1 , and the reverse breakdown voltage V of the diode device after a round of pressure shock test B2 ; Obtain the reverse leakage current I of the diode device before a round of pressure shock test R1 , and the reverse leakage current I of the diode device after a round of pressure shock test R2 ; If the V F1 and the V F2 Does not satisfy |[(V F2 -V F1 ) / V F1 )]|≤10%, or, the V B1 and the V B2 Does not satisfy |[(V B2 -V B1 ) / V B1 )]|≤10%, or, the I R1 and the I R2 Not satisfied with I R2 / I R1 ≤2, it is determined that the diode device has failed.

5. The diode performance testing method according to claim 1, characterized in that: Detecting whether the diode device fails also includes: Performing a working simulation on the diode device; Detect whether the diode device fails.

6. The diode performance testing method according to claim 5, characterized in that: Performing a working simulation on the diode device includes: A reverse bias voltage is applied to the diode device; and / or a forward rated current is passed through the diode device; and / or a forward surge current is passed through the diode device; and / or a reverse surge current is passed through the diode device.

7. The diode performance testing method according to claim 1, characterized in that: The test parameters include heating temperature, impact pressure, impact time, and impact speed. The pressure impact test includes: Heating the stamping device to a preset heating temperature; The punching device is controlled to continuously impact the diode device according to a preset impact pressure and a preset impact speed, and the duration is a preset impact time.

8. The diode performance testing method according to claim 7, characterized in that: Adjust test parameters, including: At least one or more of the heating temperature, the impact pressure, the impact time and the impact speed are increased in a certain proportion.

9. A diode performance testing device, characterized in that: include: A failure detection device, used to detect whether the diode device to be tested has failed; A stamping device, used for performing a pressure shock test on a diode device to be tested, wherein the pressure shock test comprises applying a shock to the diode device using a heated stamping device; A processing device, used for controlling the stamping device to perform at least one round of pressure shock test on the diode device to be tested; The processing device is also used to control the failure detection device to detect whether the diode device has failed after each round of pressure shock test. If the diode device has failed, the compressive strength of the diode device is determined according to the test parameters used in the previous round of pressure shock test, and the next round of pressure shock test is stopped. If the diode device has not failed, the test parameters are adjusted, and the stamping device is controlled to perform the next round of pressure shock test based on the adjusted test parameters.

10. The diode performance testing device according to claim 9, characterized in that: The failure detection device includes a thermal runaway failure detection device and an electrical performance parameter failure detection device.

11. The diode performance testing device according to claim 10, characterized in that: The diode performance testing device further comprises a limiting device for fixing the diode device to be tested, and the limiting device is also used to be electrically connected to the diode device to be tested; The thermal runaway failure detection device comprises a power supply, and the power supply is electrically connected to the limiting device.

12. The diode performance testing device according to claim 9, characterized in that: The punching device comprises: Pressure rod; A pressure head fixed at one end of the pressure rod; A driving member, used for driving the pressing rod to move, thereby driving the pressing head to impact the diode device; A heating element is used to heat the pressing rod and the pressing head.

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