A power device breakdown voltage parameter testing system and method

Abstract

The present invention provides a power device breakdown voltage parameter testing system and method, wherein a control module is respectively connected to a high-voltage power supply module, a current regulation module, a digital-to-analog conversion module, and an acquisition card; the digital-to-analog conversion module is connected to the current regulation module; the positive terminal of the high-voltage power supply module is connected to the first terminal of the current regulation module, the negative terminal of the high-voltage power supply module is connected to the emitter of the IGBT to be tested, and the second terminal of the current regulation module is connected to the collector of the IGBT to be tested; the acquisition card is connected to the data acquisition module, the data acquisition module is also connected to the collector and emitter of the IGBT to be tested, and the acquisition card is also used to connect to a host computer. By changing the current setting conditions, the current in the power supply circuit of the IGBT to be tested can be correspondingly adjusted, thereby completing the breakdown voltage test under a high-voltage and set current value environment, meeting the needs of testing the breakdown voltage parameters of the IGBT in various test scenarios.

Description

Technical Field

[0001] The present invention relates to the field of chip testing, and in particular to a system and method for testing breakdown voltage parameters of a power device. Background Art

[0002] In today's era of the prevalence of new energy, devices like high-speed rail and new energy vehicles have become indispensable aids in daily life and work, bringing unprecedented convenience to life. Power semiconductor devices play a key role in the widespread use of these devices. As a mainstream new power semiconductor device, the insulated gate bipolar transistor (IGBT) combines the advantages of both MOS and triodes, offering high input impedance, low drive power, simple control circuits, low switching losses, high speed, and high operating frequency.

[0003] However, despite the numerous advantages of IGBTs, the booming market also faces numerous quality and safety challenges. Extreme environments such as high temperature, high humidity, high salt spray, and high altitude can affect the performance of IGBT modules and even cause them to fail. As power system voltage levels continue to rise, IGBT modules must withstand higher voltages. However, improving the IGBT's withstand voltage performance comes at the expense of switching performance.

[0004] In order to ensure the normal operation and safety of the IGBT, the breakdown voltage parameters of the IGBT need to be tested under various test scenarios. How to meet this test requirement has become one of the difficult problems that technical personnel in this field are concerned about. Summary of the Invention

[0005] The object of the present invention is to provide a system and method for testing the breakdown voltage parameters of a power device to improve the above-mentioned problem.

[0006] In order to achieve the above objectives, the technical solutions adopted in the embodiments of the present invention are as follows:

[0007] In a first aspect, an embodiment of the present invention provides a power device breakdown voltage parameter testing system, the testing system comprising: a control module, a high-voltage power supply module, a current regulation module, a digital-to-analog conversion module, a data acquisition module, and an acquisition card; the control module is connected to the high-voltage power supply module, the current regulation module, the digital-to-analog conversion module, and the acquisition card, respectively, and the digital-to-analog conversion module is connected to the current regulation module;

[0008] The positive end of the high-voltage power supply module is connected to the first end of the current regulating module, the negative end of the high-voltage power supply module is connected to the emitter of the IGBT to be tested, and the second end of the current regulating module is connected to the collector of the IGBT to be tested;

[0009] The acquisition card is connected to the data acquisition module, and the data acquisition module is also connected to the collector and emitter of the IGBT to be tested. The acquisition card is also used to connect to a host computer.

[0010] Optionally, when the test is started, the control module is used to send a switch control signal to the high-voltage power supply module to control the high-voltage power supply module to switch to a working state, and send a set current value matching a current setting condition to the digital-to-analog conversion module;

[0011] The digital-to-analog conversion module is used to provide a reference voltage to the current regulation module, and the reference voltage matches the set current value;

[0012] The current regulating module is used to regulate the loop current according to the reference voltage so that the loop current is maintained at the set current value, and the loop current is the current on the power supply circuit of the IGBT to be tested;

[0013] The data acquisition module is used to collect a target voltage according to a set period, where the target voltage is the voltage between the collector and emitter of the IGBT to be tested;

[0014] The control module is further configured to send a trigger instruction to the acquisition card after a preset time period after the test is started;

[0015] The acquisition card is used to perform analog-to-digital conversion on the target voltage according to the set acquisition frequency after obtaining the trigger instruction, and send the conversion result to the host computer so that the host computer can determine the breakdown voltage of the IGBT to be tested under the current setting conditions.

[0016] Optionally, the current regulating module includes a current limiting protection unit, a gear selection unit and a current preset unit;

[0017] The input end of the current limiting protection unit is connected to the high-voltage power supply module, the output end of the current limiting protection unit is connected to the input end of the gear selection unit, the output end of the gear selection unit is connected to the collector of the IGBT to be tested, and the acquisition end of the gear selection unit is connected to the first input end of the current preset unit;

[0018] The control terminal of the gear selection unit is connected to the control module, the second input terminal of the current preset unit is connected to the digital-to-analog conversion module, and the output terminal of the current preset unit is connected to the first control terminal of the current limiting protection unit. The gear selection unit includes at least two acquisition paths, and the resistance values ​​of the sampling resistors deployed in different acquisition paths are different;

[0019] The control module is used to send a gear position signal to the gear selection unit according to the set current value;

[0020] The gear selection unit is used to switch the target acquisition path to conduction and feed back the path voltage to the current preset unit; wherein the target acquisition path is the acquisition path corresponding to the acquisition gear signal switching, and the path voltage is the voltage across the sampling resistor in the target acquisition path;

[0021] The current preset unit is used to generate an adjustment signal according to the reference voltage and the path voltage, and provide the adjustment signal to the current limiting protection unit;

[0022] The current limiting protection unit is used to adjust its internal resistance according to the adjustment signal, so that the loop current is maintained at the set current value.

[0023] Optionally, the current limiting protection unit is further connected to the control module;

[0024] The control module is further configured to send a current limiting gear signal to the current limiting protection unit;

[0025] The current limiting protection unit is used to determine the maximum adjustment range of the internal resistance according to the current limiting gear signal.

[0026] Optionally, the test system further includes an isolation module;

[0027] The input end of the isolation module is connected to the control module, and the output end of the isolation module is respectively connected to the high-voltage power supply module, the current limiting protection unit, the gear selection unit and the digital-to-analog conversion module.

[0028] Optionally, the high-voltage power supply module includes a high-voltage direct current power supply and a high-voltage switch unit;

[0029] A switch device regulated by the switch control signal is provided between the first end and the second end of the high-voltage switch unit, the first end of the high-voltage switch unit is connected to the positive end of the high-voltage DC power supply, and the second end of the high-voltage switch unit is connected to the input end of the current limiting protection unit;

[0030] The third terminal of the high-voltage switch unit is connected to the negative terminal of the high-voltage DC power supply, and the fourth terminal of the high-voltage switch unit is connected to the emitter of the IGBT to be tested.

[0031] Optionally, the switching device is a relay.

[0032] Optionally, the test system further includes a threshold protection module;

[0033] The threshold protection module is connected to the digital-to-analog conversion module, the data acquisition module and the control module respectively;

[0034] The control module is further configured to send a set voltage value matching the voltage setting condition to the digital-to-analog conversion module;

[0035] The digital-to-analog conversion module is used to provide a threshold voltage to the threshold protection module, and the threshold voltage matches the set voltage value;

[0036] The data acquisition module is used to transmit the acquired target voltage to the threshold protection module;

[0037] The threshold protection module is used to send an alarm prompt to the control module when the target voltage exceeds the threshold voltage, so that the control module stops testing.

[0038] Optionally, the test system further includes a communication module, wherein the communication module is connected to the control module;

[0039] The communication module is used to send the voltage setting conditions and current setting conditions transmitted by the host computer to the control module.

[0040] In a second aspect, an embodiment of the present invention provides a method for testing breakdown voltage parameters of a power device, which is applied to the above-mentioned test system. The method includes:

[0041] When the test is started, the control module sends a switch control signal to the high-voltage power supply module to control the high-voltage power supply module to switch to the working state, and sends a set current value matching the current setting condition to the digital-to-analog conversion module;

[0042] The digital-to-analog conversion module provides a reference voltage to the current regulation module, and the reference voltage matches the set current value;

[0043] The current regulating module regulates the loop current according to the reference voltage so that the loop current is maintained at the set current value, wherein the loop current is the current on the power supply circuit of the IGBT to be tested;

[0044] The data acquisition module acquires a target voltage according to a set period, wherein the target voltage is the voltage between the collector and emitter of the IGBT to be tested;

[0045] The control module sends a trigger instruction to the acquisition card after a preset time after the test is started;

[0046] After receiving the trigger instruction, the acquisition card performs analog-to-digital conversion on the target voltage according to the set acquisition frequency, and sends the conversion result to the host computer so that the host computer can determine the breakdown voltage of the IGBT to be tested under the current setting condition.

[0047] Compared with the prior art, the embodiment of the present invention provides a power device breakdown voltage parameter testing system and method, the testing system includes: a control module, a high-voltage power supply module, a current regulation module, a digital-to-analog conversion module, a data acquisition module and an acquisition card; the control module is respectively connected to the high-voltage power supply module, the current regulation module, the digital-to-analog conversion module and the acquisition card, and the digital-to-analog conversion module is connected to the current regulation module; the positive end of the high-voltage power supply module is connected to the first end of the current regulation module, the negative end of the high-voltage power supply module is connected to the emitter of the IGBT to be tested, and the second end of the current regulation module is connected to the collector of the IGBT to be tested; the acquisition card is connected to the data acquisition module, the data acquisition module is also connected to the collector and emitter of the IGBT to be tested, and the acquisition card is also used to connect to a host computer. By changing the current setting condition, the current on the power supply circuit of the IGBT to be tested can be correspondingly adjusted, thereby completing the breakdown voltage test under a high-voltage and set current value environment, meeting the needs of testing the breakdown voltage parameters of the IGBT in various test scenarios.

[0048] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0050] Figure 1 This is one of the structural diagrams of the power device breakdown voltage parameter testing system provided by an embodiment of the present invention.

[0051] Figure 2 This is a second structural diagram of a power device breakdown voltage parameter testing system provided by an embodiment of the present invention.

[0052] Figure 3 This is the third structural diagram of the power device breakdown voltage parameter testing system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0054] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0055] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are used only to distinguish the description and should not be understood as indicating or implying relative importance.

[0056] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0057] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limiting the present invention.

[0058] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed" and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, or electrical connections; direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0059] The following embodiments of the present invention are described in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0060] The embodiment of the present invention provides a power device breakdown voltage parameter testing system, which can complete the breakdown voltage test under high voltage and set current value environment. Figure 1 , Figure 1 This is one of the structural diagrams of the power device breakdown voltage parameter testing system provided by an embodiment of the present invention.

[0061] The power device breakdown voltage parameter test system includes: a control module, a high-voltage power supply module, a current regulation module, a digital-to-analog conversion module, a data acquisition module and an acquisition card; the control module is connected to the high-voltage power supply module, the current regulation module, the digital-to-analog conversion module and the acquisition card respectively, and the digital-to-analog conversion module is connected to the current regulation module.

[0062] The positive end of the high-voltage power module is connected to the first end of the current regulation module, the negative end of the high-voltage power module is connected to the emitter of the IGBT to be tested, and the second end of the current regulation module is connected to the collector of the IGBT to be tested.

[0063] The high-voltage power supply module can be a DC high-voltage power supply module, and the output voltage is greater than a preset voltage. The preset voltage can be set according to test requirements and can be, but is not limited to, 1200V.

[0064] The acquisition card is connected to the data acquisition module, and the data acquisition module is also connected to the collector and emitter of the IGBT to be tested. The acquisition card is also used to connect to the host computer.

[0065] In an optional embodiment, when the test is started, the control module is used to send a switch control signal to the high-voltage power supply module to control the high-voltage power supply module to switch to the working state, and send a set current value matching the current setting condition to the digital-to-analog conversion module.

[0066] The current setting condition can be a current transmitted by the communication module to the host computer. When the high-voltage power supply module is switched to the working state, it outputs high-voltage direct current to the back end, and when it is switched to the non-working state, it stops outputting.

[0067] The digital-to-analog conversion module is used to provide a reference voltage to the current regulation module, and the reference voltage matches the set current value.

[0068] The digital-to-analog conversion module can perform digital-to-analog conversion according to the set current value, thereby generating and providing a reference voltage to the current regulation module.

[0069] The current regulation module is used to regulate the loop current according to the reference voltage so that the loop current is maintained at a set current value. The loop current is the current on the power supply circuit of the IGBT to be tested.

[0070] The data acquisition module is used to collect the target voltage according to the set period. The target voltage is the voltage between the collector and emitter of the IGBT to be tested.

[0071] The control module is also used to send a trigger instruction to the acquisition card after a preset time after the test is started.

[0072] The preset duration can be set based on test experience.

[0073] After receiving the trigger instruction, the acquisition card is used to perform analog-to-digital conversion on the target voltage according to the set acquisition frequency, and send the conversion result to the host computer so that the host computer can determine the breakdown voltage of the IGBT to be tested under the current setting conditions.

[0074] In the power device breakdown voltage parameter testing system provided in an embodiment of the present invention, by changing the current setting conditions, the current on the power supply circuit of the IGBT to be tested can be adjusted accordingly, thereby completing the breakdown voltage test under a high voltage and set current value environment, meeting the needs of testing the breakdown voltage parameters of the IGBT in various test scenarios.

[0075] In an optional implementation, the control module or the host computer may further send a voltage adjustment signal to the high-voltage power supply module to enable the high-voltage power supply module to change the output voltage.

[0076] Please continue to refer to Figure 1 In an optional embodiment, the current regulation module includes a current limiting protection unit, a gear selection unit and a current preset unit.

[0077] The input end of the current limiting protection unit (as the first end of the current regulating module) is connected to the high-voltage power supply module (the positive end), the output end of the current limiting protection unit is connected to the input end of the gear selection unit, the output end of the gear selection unit (as the second end of the current regulating module) is connected to the collector of the IGBT to be tested, and the acquisition end of the gear selection unit is connected to the first input end of the current preset unit.

[0078] The control end of the gear selection unit is connected to the control module, the second input end of the current preset unit is connected to the digital-to-analog conversion module, the output end of the current preset unit is connected to the first control end of the current limiting protection unit, and the gear selection unit includes at least two acquisition paths, and the resistance values ​​of the sampling resistors deployed on different acquisition paths are different.

[0079] The control module is used to send a gear position signal to the gear selection unit according to the set current value;

[0080] The gear selection unit is used to switch the target acquisition path to conduction and feed back the path voltage to the current preset unit; wherein, the target acquisition path is the acquisition path corresponding to the acquisition gear signal switching, the path voltage is the voltage across the sampling resistor in the target acquisition path, and the current flowing through the target acquisition path is the loop current.

[0081] The two ends of the target acquisition path are respectively connected to the output end of the current limiting protection unit and the collector of the IGBT to be tested. When the set current value is smaller, it is necessary to select an acquisition path with a larger sampling resistor value. When the set current value is larger, select an acquisition path with a smaller sampling resistor value to ensure the acquisition effect.

[0082] The current preset unit is used to generate an adjustment signal according to the reference voltage (provided by the digital-to-analog conversion module) and the path voltage, and provide the adjustment signal to the current limiting protection unit.

[0083] The current limiting protection unit is used to adjust its internal resistance according to the adjustment signal, so that the loop current is maintained at a set current value.

[0084] Please continue to refer to Figure 1 In an optional embodiment, the second regulating end of the current limiting protection unit is also connected to the control module.

[0085] The control module is further configured to send a current limiting gear position signal to the current limiting protection unit.

[0086] Optionally, the current limiting gear signal corresponds to the output voltage and set current value of the high-voltage power supply module.

[0087] The current limiting protection unit is used to determine the maximum adjustment range of the internal resistance according to the current limiting gear signal, so as to avoid drastic fluctuations in current.

[0088] Please refer to Figure 2 , Figure 2 This is a second structural diagram of a power device breakdown voltage parameter testing system provided by an embodiment of the present invention. The testing system also includes an isolation module.

[0089] The input end of the isolation module is connected to the control module, and the output end of the isolation module is respectively connected to the high-voltage power supply module, the current limiting protection unit, the gear selection unit and the digital-to-analog conversion module. The isolation module is used to forward the signal or value sent by the control module to the corresponding unit or module.

[0090] The isolation module is designed to prevent interference and noise from the subsequent high-voltage circuits from affecting the previous control module circuits, ensuring accurate and stable signal transmission. The high-speed and high-voltage isolation optocoupler TLP293 and digital isolator π141E61Q can be used to isolate input control signals and SPI signals from the output circuits, ensuring secure and stable signal transmission and preventing electromagnetic interference.

[0091] Please refer to Figure 3 , Figure 3 This is a third structural diagram of a power device breakdown voltage parameter testing system according to an embodiment of the present invention. The high-voltage power supply module includes a high-voltage DC power supply and a high-voltage switch unit.

[0092] A switching device regulated by a switch control signal is provided between the first and second ends of the high-voltage switch unit. The first end of the high-voltage switch unit is connected to the positive end of the high-voltage DC power supply, and the second end of the high-voltage switch unit (serving as the positive end of the high-voltage power supply module) is connected to the input end of the current limiting protection unit.

[0093] The third terminal of the high-voltage switch unit is connected to the negative terminal of the high-voltage DC power supply, and the fourth terminal of the high-voltage switch unit (as the negative terminal of the high-voltage power supply module) is connected to the emitter of the IGBT to be tested.

[0094] When the switch device is closed, the high-voltage power module switches to a working state, and when the switch device is opened, the high-voltage power module switches to a non-working state.

[0095] In the embodiment diagram of the present invention, the switching device can be, but is not limited to, a relay, and the relay is more suitable for testing the corresponding high-voltage environment.

[0096] Please continue to refer to Figure 1 In an optional embodiment, the test system further includes a threshold protection module.

[0097] The threshold protection module is connected to the digital-to-analog conversion module, the data acquisition module and the control module respectively.

[0098] The control module is further configured to send a set voltage value matching the voltage setting condition to the digital-to-analog conversion module.

[0099] The voltage setting condition may be received by the communication module from the host computer.

[0100] The digital-to-analog conversion module is used to provide a threshold voltage to the threshold protection module, and the threshold voltage matches the set voltage value.

[0101] The digital-to-analog conversion module can perform digital-to-analog conversion according to the set voltage value, thereby generating and providing a threshold voltage to the threshold protection module.

[0102] The data acquisition module is used to transmit the acquired target voltage to the threshold protection module.

[0103] The threshold protection module is used to send an alarm prompt to the control module when the target voltage exceeds the threshold voltage, so that the control module stops testing and plays a role in safety protection.

[0104] In an optional implementation, the test system further includes a communication module, which is connected to the control module.

[0105] The communication module is used to send the voltage setting conditions and current setting conditions transmitted by the host computer to the control module.

[0106] In an optional embodiment, the data acquisition module includes a data acquisition unit and a data processing unit. The data acquisition unit is used to acquire the target voltage, and the data processing unit is used to process the voltage signal acquired by the data acquisition unit and attenuate it to a range that can be acquired by the acquisition card.

[0107] In an optional embodiment, the test system further includes a discharge module, which is respectively connected to the collector and emitter of the IGBT to be tested. The discharge module is used to discharge the entire test system after the test is completed.

[0108] In an optional embodiment, the output terminal of the gear selection unit is connected to the collector signal input terminal CF of the IGBT under test, the negative terminal of the high-voltage power supply module is connected to the emitter signal input terminal EF of the IGBT under test, and the gate signal input terminal GF of the IGBT under test is short-circuited with the emitter measurement terminal ES of the IGBT under test. One terminal of the data acquisition module is connected to the collector measurement terminal CS of the IGBT under test, and the other terminal of the data acquisition module is connected to the emitter measurement terminal ES of the IGBT under test.

[0109] In an optional embodiment, the test system also includes a power supply module, which includes a power supply and an adjustable voltage stabilizing circuit connected to the power supply. The adjustable voltage stabilizing circuit is also connected to the above-mentioned modules in the test system, so as to supply energy to the corresponding modules after voltage conversion.

[0110] An embodiment of the present invention further provides a method for testing breakdown voltage parameters of a power device, which can be applied to, but is not limited to, the above-mentioned test system. The method for testing breakdown voltage parameters of a power device includes: S11 to S16, which are described in detail as follows.

[0111] S11, when the test is started, the control module sends a switch control signal to the high-voltage power supply module to control the high-voltage power supply module to switch to the working state, and sends a set current value matching the current setting condition to the digital-to-analog conversion module.

[0112] S12, the digital-to-analog conversion module provides a reference voltage to the current regulation module, and the reference voltage matches the set current value.

[0113] S13, the current regulating module regulates the loop current according to the reference voltage so that the loop current is maintained at a set current value, where the loop current is the current on the power supply circuit of the IGBT to be tested.

[0114] S14, the data acquisition module acquires the target voltage according to the set period, where the target voltage is the voltage between the collector and emitter of the IGBT to be tested.

[0115] S15, the control module sends a trigger instruction to the acquisition card after a preset time after the test is started.

[0116] S16, after receiving the trigger instruction, the acquisition card performs analog-to-digital conversion on the target voltage according to the set acquisition frequency, and sends the conversion result to the host computer so that the host computer can determine the breakdown voltage of the IGBT to be tested under the current setting condition.

[0117] It should be noted that the power device breakdown voltage parameter testing method provided in this embodiment can perform the functions and uses described in the above-mentioned power device breakdown voltage parameter testing system embodiment to achieve the corresponding technical effects. For the sake of brevity, any parts not mentioned in this embodiment can be referred to the corresponding content in the above-mentioned embodiments.

[0118] In summary, an embodiment of the present invention provides a power device breakdown voltage parameter testing system and method, the testing system includes: a control module, a high-voltage power supply module, a current regulation module, a digital-to-analog conversion module, a data acquisition module and an acquisition card; the control module is respectively connected to the high-voltage power supply module, the current regulation module, the digital-to-analog conversion module and the acquisition card, and the digital-to-analog conversion module is connected to the current regulation module; the positive end of the high-voltage power supply module is connected to the first end of the current regulation module, the negative end of the high-voltage power supply module is connected to the emitter of the IGBT to be tested, and the second end of the current regulation module is connected to the collector of the IGBT to be tested; the acquisition card is connected to the data acquisition module, the data acquisition module is also connected to the collector and emitter of the IGBT to be tested, and the acquisition card is also used to connect to a host computer. By changing the current setting condition, the current on the power supply circuit of the IGBT to be tested can be adjusted accordingly, thereby completing the breakdown voltage test under a high voltage and set current value environment, meeting the needs of testing the breakdown voltage parameters of the IGBT in various test scenarios.

[0119] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

[0120] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A power device breakdown voltage parameter testing system, characterized in that: The test system includes: a control module, a high-voltage power supply module, a current regulation module, a digital-to-analog conversion module, a data acquisition module, and an acquisition card; the control module is connected to the high-voltage power supply module, the current regulation module, the digital-to-analog conversion module, and the acquisition card respectively, and the digital-to-analog conversion module is connected to the current regulation module; The positive end of the high-voltage power supply module is connected to the first end of the current regulating module, the negative end of the high-voltage power supply module is connected to the emitter of the IGBT to be tested, and the second end of the current regulating module is connected to the collector of the IGBT to be tested; The acquisition card is connected to the data acquisition module, the data acquisition module is also connected to the collector and emitter of the IGBT to be tested, and the acquisition card is also used to connect to the host computer; The current regulation module includes a current limiting protection unit, a gear selection unit, and a current preset unit. The input end of the current limiting protection unit is connected to the high-voltage power supply module, the output end of the current limiting protection unit is connected to the input end of the gear selection unit, the output end of the gear selection unit is connected to the collector of the IGBT to be tested, and the acquisition end of the gear selection unit is connected to the first input end of the current preset unit. The control terminal of the gear selection unit is connected to the control module, the second input terminal of the current preset unit is connected to the digital-to-analog conversion module, and the output terminal of the current preset unit is connected to the first control terminal of the current limiting protection unit. The gear selection unit includes at least two acquisition paths, and the resistance values ​​of the sampling resistors deployed in different acquisition paths are different; The control module is used to send a set current value that matches the current setting condition to the digital-to-analog conversion module; the digital-to-analog conversion module is used to provide a reference voltage to the current regulation module, and the reference voltage matches the set current value; The control module is used to send a gear position signal to the gear selection unit according to the set current value; The gear selection unit is used to switch the target acquisition path to conduction and feed back the path voltage to the current preset unit; wherein the target acquisition path is the acquisition path corresponding to the acquisition gear signal, and the path voltage is the voltage across the sampling resistor in the target acquisition path; The current preset unit is used to generate an adjustment signal according to the reference voltage and the path voltage, and provide the adjustment signal to the current limiting protection unit; The current limiting protection unit is used to adjust its internal resistance according to the adjustment signal, so that the loop current is maintained at the set current value.

2. The power device breakdown voltage parameter testing system according to claim 1, characterized in that: When the test is started, the control module is used to send a switch control signal to the high-voltage power supply module to control the high-voltage power supply module to switch to a working state; The current regulating module is used to regulate the loop current according to the reference voltage so that the loop current is maintained at the set current value, and the loop current is the current on the power supply circuit of the IGBT to be tested; The data acquisition module is used to collect a target voltage according to a set period, where the target voltage is the voltage between the collector and emitter of the IGBT to be tested; The control module is further configured to send a trigger instruction to the acquisition card after a preset time period after the test is started; The acquisition card is used to perform analog-to-digital conversion on the target voltage according to the set acquisition frequency after obtaining the trigger instruction, and send the conversion result to the host computer so that the host computer can determine the breakdown voltage of the IGBT to be tested under the current setting conditions.

3. The power device breakdown voltage parameter testing system according to claim 1, wherein: The current limiting protection unit is also connected to the control module; The control module is further configured to send a current limiting gear signal to the current limiting protection unit; The current limiting protection unit is used to determine the maximum adjustment range of the internal resistance according to the current limiting gear signal.

4. The power device breakdown voltage parameter testing system according to claim 3, characterized in that: The test system further includes an isolation module; The input end of the isolation module is connected to the control module, and the output end of the isolation module is respectively connected to the high-voltage power supply module, the current limiting protection unit, the gear selection unit and the digital-to-analog conversion module.

5. The power device breakdown voltage parameter testing system according to claim 3, characterized in that: The high-voltage power supply module includes a high-voltage DC power supply and a high-voltage switch unit; A switch device regulated by a switch control signal is provided between the first end and the second end of the high-voltage switch unit, the first end of the high-voltage switch unit is connected to the positive end of the high-voltage DC power supply, and the second end of the high-voltage switch unit is connected to the input end of the current limiting protection unit; The third terminal of the high-voltage switch unit is connected to the negative terminal of the high-voltage DC power supply, and the fourth terminal of the high-voltage switch unit is connected to the emitter of the IGBT to be tested.

6. The power device breakdown voltage parameter testing system according to claim 5, characterized in that: The switching device is a relay.

7. The power device breakdown voltage parameter testing system according to claim 2, wherein: The test system also includes a threshold protection module; The threshold protection module is connected to the digital-to-analog conversion module, the data acquisition module and the control module respectively; The control module is further configured to send a set voltage value matching the voltage setting condition to the digital-to-analog conversion module; The digital-to-analog conversion module is used to provide a threshold voltage to the threshold protection module, and the threshold voltage matches the set voltage value; The data acquisition module is used to transmit the acquired target voltage to the threshold protection module; The threshold protection module is used to send an alarm prompt to the control module when the target voltage exceeds the threshold voltage, so that the control module stops testing.

8. The power device breakdown voltage parameter testing system according to claim 7, wherein: The test system further includes a communication module, wherein the communication module is connected to the control module; The communication module is used to send the voltage setting conditions and current setting conditions transmitted by the host computer to the control module.

9. A method for testing breakdown voltage parameters of a power device, characterized in that: The test system according to any one of claims 1 to 8, wherein the method comprises: When the test is started, the control module sends a switch control signal to the high-voltage power supply module to control the high-voltage power supply module to switch to the working state, and sends a set current value matching the current setting condition to the digital-to-analog conversion module; The digital-to-analog conversion module provides a reference voltage to the current regulation module, and the reference voltage matches the set current value; The current regulating module regulates the loop current according to the reference voltage so that the loop current is maintained at the set current value, wherein the loop current is the current on the power supply circuit of the IGBT to be tested; The data acquisition module acquires a target voltage according to a set period, wherein the target voltage is the voltage between the collector and emitter of the IGBT to be tested; The control module sends a trigger instruction to the acquisition card after a preset time after the test is started; After receiving the trigger instruction, the acquisition card performs analog-to-digital conversion on the target voltage according to the set acquisition frequency, and sends the conversion result to the host computer so that the host computer can determine the breakdown voltage of the IGBT to be tested under the current setting condition.

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