Online evaluation system and method for degradation effect of power device

Abstract

The invention relates to an online evaluation system and method for a degradation effect of a power device, and relates to the technical field of testing. The system comprises a high-power microwave irradiation device, a transient extreme stress loading device and a semiconductor parameter analyzer, the power device is arranged in the high-power microwave irradiation device and is respectively connected with the transient extreme stress loading device and the semiconductor parameter analyzer; the high-power microwave irradiation device is used for providing high-power microwave irradiation stress for the power device; the transient extreme stress loading device is used for providing transient extreme stress for the power device; and the semiconductor parameter analyzer is used for acquiring the initial electrical parameters of the power device, acquiring the test electrical parameters of the high-power microwave irradiation stress and the transient extreme stress applied to the power device, and determining the online evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters. According to the method, the degradation of the power device under the high-power microwave irradiation stress and the transient extreme stress can be evaluated on line.

Description

Technical Field

[0001] The present application relates to the field of testing technologies, and particularly to an online evaluation system and method for the degradation effect of power devices. Background Art

[0002] With the rapid development of unmanned aerial vehicle (UAV) technology, it has been widely used not only in civilian fields such as disaster rescue, power inspection, mapping, and agricultural plant protection, but also plays an increasingly significant role in military fields.

[0003] Generally, high power microwave (HPM) can interfere with or damage the electronic system of a UAV through high power electromagnetic pulses, inducing high voltage and large current in the electronic system of the UAV, resulting in the degradation or even failure of power devices inside the electronic system of the UAV, causing signal distortion, equipment failure, or functional chaos of the UAV. Therefore, how to accurately test and evaluate the degradation characteristics of power devices under high power microwave irradiation is an urgent problem to be solved. Summary of the Invention

[0004] Based on this, it is necessary to provide an online evaluation system and method for the degradation effect of power devices, which can test and evaluate the electrical parameter degradation characteristics of power devices under high power microwave irradiation stress and transient extreme stress.

[0005] An embodiment of the present application provides an online evaluation system for the degradation effect of power devices, including: a high power microwave irradiation device, a transient extreme stress loading device, and a semiconductor parameter analyzer; the power device is disposed in the high power microwave irradiation device and is respectively connected to the transient extreme stress loading device and the semiconductor parameter analyzer; wherein,

[0006] The high power microwave irradiation device is configured to provide high power microwave irradiation stress to the power device;

[0007] The transient extreme stress loading device is configured to provide transient extreme stress to the power device;

[0008] The semiconductor parameter analyzer is configured to obtain the initial electrical parameters of the power device, obtain the test electrical parameters of the power device when the high power microwave irradiation stress and the transient extreme stress are applied, and determine the online evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters.

[0009] In one embodiment, the transient extreme stress loading device includes:

[0010] A gate drive circuit, connected to the gate of the power device, for providing a gate drive signal;

[0011] A transient extreme stress loading circuit, which is respectively connected to the first pole and the second pole of the power device, is used to provide the transient extreme stress; the transient extreme stress includes at least one of short-circuit current stress, avalanche stress and surge current stress;

[0012] A control circuit, which is respectively connected to the gate drive circuit and the transient extreme stress loading circuit, is used to control the working states of the gate drive circuit and the transient extreme stress loading circuit, so as to provide the transient extreme stress to the power device.

[0013] In one embodiment, the transient extreme stress loading circuit includes a short-circuit current stress loading module, and the short-circuit current stress loading module is used to provide the short-circuit current stress to the power device; wherein,

[0014] The short-circuit current stress loading module includes a first capacitor, a first resistor and a first DC power supply. The first end of the first capacitor is respectively connected to the first end of the first resistor and the second pole of the power device. The second end of the first capacitor is connected to the first pole of the power device, and the second end of the first capacitor is grounded. The second end of the first resistor is grounded through the first DC power supply, and the control end of the first DC power supply is connected to the control circuit.

[0015] In one embodiment, the transient extreme stress loading circuit includes an avalanche stress loading module, and the avalanche stress loading module is used to provide the avalanche stress to the power device; wherein,

[0016] The avalanche stress loading module includes a second capacitor, a first inductor and a second DC power supply; wherein, the first end of the second capacitor is respectively connected to the first end of the first inductor and the first end of the second DC power supply. The second end of the second capacitor is respectively connected to the first pole of the power device and the second end of the second DC power supply. The second end of the second capacitor is grounded. The second end of the first inductor is connected to the second pole of the power device, and the control end of the second DC power supply is connected to the control circuit.

[0017] In one embodiment, the transient extreme stress loading circuit includes a surge current stress loading module, and the surge current stress loading module is used to provide the surge current stress to the power device; wherein,

[0018] The surge current stress loading module includes a rectifier bridge, a switching tube, and a second inductor. Among them, the first end of the rectifier bridge is connected to the first pole of the switching tube, the second end of the rectifier bridge is connected to the second pole of the power device, and the second end of the rectifier bridge is grounded. The control end of the rectifier bridge is connected to the control circuit. The second pole of the switching tube is connected to the first pole of the power device through the second inductor, and the gate of the switching tube is connected to the gate driving circuit.

[0019] In one embodiment, the high-power microwave irradiation device includes;

[0020] A resonant cavity, where the power device is disposed in the resonant cavity;

[0021] A high-power microwave radiation source for providing a high-power microwave signal;

[0022] An excitation probe is disposed in the resonant cavity and connected to the high-power microwave radiation source for generating resonance in the resonant cavity according to the high-power microwave signal and providing the high-power microwave irradiation stress to the power device.

[0023] In one embodiment, the high-power microwave radiation source includes a microwave signal source, a power amplifier, a circulator, and a directional coupler. Among them,

[0024] The microwave signal source is used to provide a microwave signal;

[0025] The power amplifier is connected to the microwave signal source, and the power amplifier is used to perform power amplification processing on the microwave signal and output a high-power microwave signal;

[0026] The circulator is respectively connected to the power amplifier and the directional coupler, and the circulator is used to transmit the high-power microwave signal from the power amplifier to the directional coupler;

[0027] The directional coupler is connected to the excitation probe, and the directional coupler is used to transmit the high-power microwave signal from the circulator to the excitation probe.

[0028] The embodiments of the present application provide a method for on-line evaluation of the degradation effect of a power device. The method includes:

[0029] Obtain the initial electrical parameters of the power device;

[0030] Apply high-power microwave irradiation stress and transient extreme stress to the power device;

[0031] Obtain the test electrical parameters of the power device when the high-power microwave irradiation stress and the transient extreme stress are applied;

[0032] Obtain an online evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters.

[0033] In one embodiment, the obtaining the online evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters includes:

[0034] Judge whether the power device fails according to the initial electrical parameters and the test electrical parameters;

[0035] In the case where the power device does not fail, adjust at least one of the high-power microwave irradiation stress and the transient extreme stress, and perform again the step of obtaining the test electrical parameters of the power device applied with the high-power microwave irradiation stress and the transient extreme stress;

[0036] In the case where the power device fails, obtain an online evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters, and the online evaluation result is used to characterize the failure condition of the power device.

[0037] In one embodiment, applying the high-power microwave irradiation stress and the transient extreme stress to the power device includes:

[0038] Obtain the test condition parameters of the power device; the test condition parameters include high-power microwave irradiation condition parameters and transient extreme stress condition parameters;

[0039] Apply the high-power microwave irradiation stress and the transient extreme stress to the power device according to the test condition parameters.

[0040] The above-mentioned on-line evaluation system and method for the degradation effect of power devices. The on-line evaluation system for the degradation effect of power devices includes a high-power microwave irradiation device, a transient extreme stress loading device, and a semiconductor parameter analyzer. The power device is arranged in the high-power microwave irradiation device and is respectively connected to the transient extreme stress loading device and the semiconductor parameter analyzer. Among them, the high-power microwave irradiation device is used to provide high-power microwave irradiation stress to the power device; the transient extreme stress loading device is used to provide transient extreme stress to the power device; the semiconductor parameter analyzer is used to obtain the initial electrical parameters of the power device, and obtain the test electrical parameters of the power device under the application of high-power microwave irradiation stress and transient extreme stress, and determine the on-line evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters. This application organically combines a high-power microwave irradiation device, a transient extreme stress loading device, and a semiconductor parameter analyzer, realizing real-time on-line evaluation and accurate and comprehensive evaluation of the degradation effect of power devices under complex working conditions. By combining high-power microwaves with transient extreme stress, it can be closer to the actual working conditions, and based on the changes in electrical parameters, comprehensively analyze and evaluate the degradation behavior and its mechanism of power devices under complex working conditions. This application not only provides new suggestions and references for improving the reliability of power devices, but also provides strong experimental support for the high-power microwave protection of products such as UAV power modules and electric drive modules, and has broad application prospects. Description of the Drawings

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0042] Figure 1 One of the structural schematic diagrams of the on-line evaluation system for the degradation effect of power devices in an embodiment;

[0043] Figure 2 One of the structural schematic diagrams of the on-line evaluation system for the degradation effect of power devices in an embodiment;

[0044] Figure 3 One of the structural schematic diagrams of the on-line evaluation system for the degradation effect of power devices in an embodiment;

[0045] Figure 4 One of the structural schematic diagrams of the on-line evaluation system for the degradation effect of power devices in an embodiment;

[0046] Figure 5 One of the structural schematic diagrams of the on-line evaluation system for the degradation effect of power devices in an embodiment;

[0047] Figure 6 Sixth schematic structural diagram of the online evaluation system for the degradation effect of power devices in an embodiment;

[0048] Figure 7 Seventh schematic structural diagram of the online evaluation system for the degradation effect of power devices in an embodiment;

[0049] Figure 8 Schematic structural diagram of a device fixture in an embodiment;

[0050] Figure 9 Schematic flow diagram of the online evaluation method for the degradation effect of power devices in an embodiment;

[0051] Figure 10 Schematic flow diagram of the online evaluation method for the degradation effect of power devices in another embodiment;

[0052] Figure 11 Schematic flow diagram of the online evaluation method for the degradation effect of power devices in yet another embodiment.

[0053] Description of reference numerals:

[0054] 10. High-power microwave irradiation device; 11. Resonant cavity; 12. High-power microwave radiation source; 121. Microwave signal source; 122. Power amplifier; 123. Circulator; 124. Directional coupler; 1241. First directional coupler; 1242. Second directional coupler; 13. Excitation probe; 20. Transient extreme stress loading device; 21. Gate drive circuit; 211. First gate drive module; 2111. Signal generator; 2112. First gate driver; 212. Second gate drive module; 2121. Second gate driver; 213. Third gate drive module; 2131. Third gate driver; 2132. Fourth gate driver; 22. Transient extreme stress loading circuit; 221. Short-circuit current stress loading module; 222. Avalanche stress loading module; 223. Surge current stress loading module; 2231. Rectifier bridge; 2232. Switching tube; 224. Gating module; 23. Control circuit; 30. Semiconductor parameter analyzer; 31. Dynamic parameter test equipment; 32. Static parameter test equipment; 33. Oscilloscope; 34. Avalanche withstand tester; 40. Power device; 50. Power meter; 60. Device fixture; 61. Fixture body; 611. First fixture body; 612. Second fixture body; 62. Signal terminal. Detailed implementation manners

[0055] To facilitate the understanding of the present application, the present application will be described more comprehensively below with reference to the relevant accompanying drawings. Embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0056] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0057] It can be understood that the terms "first", "second", etc. used in this application can be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first resistor can be called a second resistor, and similarly, a second resistor can be called a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0058] It can be understood that for "connection" in the following embodiments, if there is an electrical signal or data transfer between the connected circuits, modules, units, etc., it should be understood as "electrical connection", "communication connection", etc.

[0059] It can be understood that "at least one" means one or more, and "a plurality" means two or more. "At least part of an element" means part or all of the element.

[0060] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprising", "including" or "having", etc. specify the presence of the stated features, wholes, steps, operations, components, parts or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the related listed items.

[0061] As mentioned in the background art, power devices are prone to degradation or even failure in a high-power microwave environment. Considering the transient extreme stresses that may be faced under actual working conditions such as the climbing and rapid maneuvering of unmanned aerial vehicles, the power devices themselves will be subjected to large currents, high electric fields, hot electron effects, etc. When the power devices operate under extreme working conditions under high-power microwave radiation, they may be more likely to degrade or fail.

[0062] Based on the above, the embodiments of the present application provide an online evaluation system and method for the degradation effect of power devices, which can accurately test and evaluate the degradation law of power devices when experiencing transient extreme stress under high-power microwave irradiation, and provide an important reference basis for the high-power microwave protection design of unmanned aerial vehicles.

[0063] In one embodiment, as Figure 1 shown, an online evaluation system for the degradation effect of power devices includes: a high-power microwave irradiation device 10, a transient extreme stress loading device 20, and a semiconductor parameter analyzer 30.

[0064] The power device 40 is a semiconductor device for processing and controlling the conversion and transmission of electrical energy. In the embodiments of the present application, the power device 40 is the power device 40 to be subjected to the degradation test, which can be denoted as DUT. For example, the power device 40 can be a power device 40 applied in an unmanned aerial vehicle (such as a motor module and / or an electric drive module). The power device 40 can include any one of silicon (Si) devices, silicon carbide (SiC) devices, and gallium nitride (GaN) devices, and the power device 40 can also include at least one of insulated gate bipolar transistors (IGBTs), metal-oxide-semiconductor field-effect transistors (MOSFETs), and thyristors. In applications, the power device 40 to be subjected to the degradation test can be selected according to actual test requirements, and no excessive limitation is made here.

[0065] The power device 40 is arranged inside the high-power microwave irradiation device 10. Among them, the high-power microwave irradiation device 10 is used to provide high-power microwave irradiation stress to the power device 40. During the test, the power device 40 can be arranged inside the high-power microwave irradiation device 10 to apply high-power microwave irradiation stress to the power device 40 inside the high-power microwave irradiation device 10, so as to realize the online evaluation of the degradation effect of the power device 40 under high-power microwave irradiation stress.

[0066] The power device 40 is respectively connected to the transient extreme stress loading device 20 and the semiconductor parameter analyzer 30. Among them, the power device 40 includes a gate, a first pole, and a second pole. For example, if the power device 40 includes a gallium nitride device, the gallium nitride device includes a gate, a source, and a drain. Another example is that if the power device 40 includes an insulated gate bipolar transistor, the insulated gate bipolar transistor includes a gate, a collector, and an emitter. In applications, the corresponding electrodes can be determined according to the type of the power device 40, and no excessive limitation is made here. Among them, the gate, the first pole, and the second pole of the power device 40 are respectively connected to the transient extreme stress loading device 20. The gate, the first pole, and the second pole of the power device 40 are respectively connected to the semiconductor parameter analyzer 30.

[0067] Among them, taking the power device 40 as a gallium nitride device as an example, the first pole of the power device 40 can be the source pole, and the second pole of the power device 40 can be the drain pole. When the power device 40 is other types of devices, such as an IGBT, the first pole of the power device 40 can be the emitter, and the second pole of the power device 40 can be the collector. In applications, the electrodes of the power device 40 can be determined correspondingly according to the specific type of the power device 40, and no excessive limitation is made here.

[0068] The transient extreme stress loading device 20 is used to provide transient extreme stress to the power device 40. Transient extreme stress refers to a high stress state that the power device 40 experiences within a short time and exceeds its normal operating conditions. The transient extreme stress can include at least one of short-circuit current stress, avalanche stress, and surge current stress. The transient extreme stress can be set according to actual test requirements, and no limitation is made here.

[0069] The semiconductor parameter analyzer 30 is used to obtain the initial electrical parameters of the power device 40, obtain the test electrical parameters of the power device 40 when it is subjected to high-power microwave irradiation stress and transient extreme stress, and determine the online evaluation result of the degradation effect of the power device 40 according to the initial electrical parameters and the test electrical parameters. Among them, the online evaluation result is used to represent the degradation characteristics of the power device 40 when it is subjected to high-power microwave irradiation stress and transient extreme stress. The initial electrical parameters refer to the electrical parameters obtained by testing the power device 40 before it is subjected to high-power microwave irradiation stress and transient extreme stress. The test electrical parameters refer to the electrical parameters obtained by testing the power device 40 when it is subjected to high-power microwave irradiation stress and transient extreme stress. The test electrical parameters can include the electrical parameters obtained by testing the power device 40 during the process of being subjected to high-power microwave irradiation stress and transient extreme stress, or can also include the electrical parameters obtained by testing the power device 40 after being subjected to high-power microwave irradiation stress and transient extreme stress, and no limitation is made here.

[0070] In the embodiments of the present application, the electrical parameters, including the initial electrical parameters and the test electrical parameters, are key indicators for describing the electrical performance of the power device 40. The electrical parameters can include at least one of transfer characteristics, output characteristics, and leakage characteristics. Among them, the transfer characteristics describe the relationship between the input voltage and the output current. The output characteristics reflect the voltage-current relationship of the power device 40 under different operating conditions. The leakage characteristic refers to the tiny current passing through the power device 40 in the off state, that is, when no signal is actively applied to turn on the power device 40. In applications, the electrical parameters are not limited to the above types, and can also be other indicators that can evaluate the device degradation degree. For example, the electrical parameters can also include threshold voltage, breakdown voltage, on-resistance, switching time, switching speed, and so on, and no excessive limitation is made here.

[0071] The online evaluation system for the degradation effect of power devices provided by the embodiments of the present application organically combines a high-power microwave irradiation device 10, a transient extreme stress loading device 20, and a semiconductor parameter analyzer 30, realizing real-time online evaluation and accurate and comprehensive evaluation of the degradation effect of power devices 40 under complex working conditions. By combining high-power microwaves with transient extreme stress, the system can be closer to the actual working conditions, and comprehensively analyze and evaluate the degradation behavior and its mechanism of power devices 40 under complex working conditions based on the changes in electrical parameters. The present application not only provides new suggestions and references for improving the reliability of power devices 40, but also provides strong experimental support for the high-power microwave protection of products such as unmanned aerial vehicle power modules and electric drive modules, and has broad application prospects.

[0072] In one embodiment, as Figure 2 shown, the transient extreme stress loading device 20 includes a gate drive circuit 21, a transient extreme stress loading circuit 22, and a control circuit 23.

[0073] The gate drive circuit 21 is connected to the gate of the power device 40. The gate drive circuit 21 is used to provide a gate drive signal. Exemplarily, the gate drive circuit 21 may include a signal source and an auxiliary power supply, where the auxiliary power supply is connected to the signal source, and the auxiliary power supply is used to provide a supply voltage for the signal source, and the signal source is used to provide a gate drive signal under the action of the supply voltage. The gate drive signal may include an enable level and a non-enable level; wherein, the power device 40 can conduct in response to the enable level, and the power device 40 can also turn off in response to the non-enable level. Exemplarily, the gate drive signal may be a square wave signal. The specific type of the gate drive signal can be specifically set according to the gate drive requirements of the power device 40, and no excessive limitation is made here. Thus, through the gate drive signal provided by the gate drive circuit 21, the on-off state of the power device 40 can be effectively controlled. For example, parameters such as the switching frequency and duty cycle of the power device 40 can be controlled to realize the online evaluation of the degradation effect of the power device 40 and meet various test requirements.

[0074] The transient extreme stress loading circuit 22 is respectively connected to the first pole and the second pole of the power device 40. The transient extreme stress loading circuit 22 is used to provide transient extreme stress. The transient extreme stress includes at least one of short-circuit current stress, avalanche stress, and surge current stress. Among them, the short-circuit current stress is the situation where when the circuit has a short circuit, the current flowing through the power device 40 will increase sharply to far exceed the normal operating level. The avalanche stress refers to the self-sustaining discharge phenomenon that occurs when the voltage applied across the power device 40 exceeds its rated breakdown voltage. The surge current stress refers to a sudden and short large current pulse.

[0075] The control circuit 23 is respectively connected to the gate drive circuit 21 and the transient extreme stress loading circuit 22, and is used to control the operating states of the gate drive circuit 21 and the transient extreme stress loading circuit 22, so as to provide transient extreme stress to the power device 40. Among them, the control circuit 23 can respectively control the gate drive circuit 21 and the transient extreme stress loading circuit 22 to be in the operating state, so as to provide transient extreme stress to the power device 40. Among them, the control circuit 23 can control the operating state of the gate drive circuit 21 to control the gate drive signal output by the gate drive circuit 21, so that parameters such as the switching frequency and duty cycle of the power device 40 can be controlled. The control circuit 23 can control the operating state of the transient extreme stress loading circuit 22 to control the type of transient extreme stress provided to the power device 40. Exemplarily, the control circuit 23 can be an FPGA (Field Programmable Gate Array) controller.

[0076] In the above embodiment, the transient extreme stress loading device 20 provides a gate drive signal through the gate drive circuit 21, provides transient extreme stress to the power device 40 through the transient extreme stress loading circuit 22 when the gate drive signal drives the power device 40, and respectively controls the operating states of the gate drive circuit 21 and the transient extreme stress loading circuit 22 through the control circuit 23. In this way, it can provide technical support for providing composite stress, namely high-power microwave irradiation stress and transient extreme stress, to the power device 40, thereby providing the possibility for studying the electrical parameter degradation characteristics of the power device 40 under composite working conditions.

[0077] In one embodiment, as Figure 3 shown, the semiconductor parameter analyzer 30 may include at least one of a dynamic parameter test device 31 and a static parameter test device 32. Among them, the dynamic parameter test device 31 can be used to test the dynamic parameters of the power device 40. For example, the turn-off time, on-resistance, etc. of the power device 40. The dynamic parameter test device 31 may include an oscilloscope 33, which can test the voltage and current of the power device 40 online in real time. The static parameter test device 32 can be used to test the static parameters of the power device 40. For example, the transfer characteristics, output characteristics, leakage characteristics, etc. of the power device 40.

[0078] In one embodiment, as Figure 4 shown, the transient extreme stress loading circuit 22 includes a short-circuit current stress loading module 221. The short-circuit current stress loading module 221 is used to provide short-circuit current stress to the power device 40.

[0079] The short - circuit current stress loading module 221 includes a first capacitor C1, a first resistor R1, and a first DC power supply U1. The first terminal of the first capacitor C1 is respectively connected to the first terminal of the first resistor R1 and the second terminal of the power device 40. The second terminal of the first capacitor C1 is connected to the first terminal of the power device 40, and the second terminal of the first capacitor C1 is grounded. The second terminal of the first resistor R1 is grounded through the first DC power supply U1, and the control terminal of the first DC power supply U1 is connected to the control circuit 23. Taking the power device 40 as a gallium nitride device as an example, the first terminal of the power device 40 can be the source electrode, and the second terminal of the power device 40 can be the drain electrode.

[0080] Among them, the first DC power supply U1 can be a high - voltage DC power supply. The first DC power supply U1 is used to provide a DC voltage, and the specific value of this DC voltage can be set accordingly according to the test requirements for applying short - circuit current stress to the power device 40, and no excessive limitation is made here.

[0081] Exemplarily, the gate driving circuit 21 includes a first gate driving module 211. The first gate driving module 211 is used to provide a first gate driving signal to the gate of the power device 40. The first gate driving module 211 can include a signal generator 2111, a first gate driver 2112, and a first protection resistor Rg1. Among them, the first terminal of the signal generator 2111 is connected to the first input terminal of the first gate driver 2112 through the first protection resistor Rg1, and the second terminal of the signal generator 2111 is connected to the second input terminal of the first gate driver 2112 and grounded.

[0082] The signal generator 2111 is used to generate an initial driving signal. Exemplarily, the initial driving signal can be a square - wave signal. For example, the high level of the initial driving signal is 3.3V, and the low level of the initial driving signal is 0V. In applications, the initial driving signal can be set according to the short - circuit current stress test requirements of the power device 40. Here, for illustrative purposes, it can also be any other suitable signal, and no excessive limitation is made.

[0083] The output terminal of the first gate driver 2112 is connected to the gate of the power device 40. The first gate driver 2112 is used to generate a first gate driving signal according to the first initial driving signal to drive the power device 40. Exemplarily, the first gate driving signal can be a square - wave signal. For example, the high level of the first gate driving signal is 8V, and the low level of the first gate driving signal is - 5V. In this way, it can ensure that the power device 40 is fully turned on and fully turned off, improving the accuracy of the test. In applications, the first gate driving signal can be set according to the short - circuit current stress test requirements of the power device 40. Here, for illustrative purposes, it can also be any other suitable signal, and no excessive limitation is made.

[0084] Exemplarily, the semiconductor parameter analyzer 30 may include an oscilloscope 33, which may be connected to the gate, first electrode, and second electrode of the power device 40, respectively, and may be used to measure the voltage and current of the power device 40; for example, taking the power device 40 as a gallium nitride device, the first electrode of the power device 40 may be a source electrode, and the second electrode of the power device 40 may be a drain electrode.

[0085] The above-mentioned short-circuit current stress loading module 221, through the first capacitor C1, the first resistor R1 and the first DC power supply U1, combined with the first gate driving module 211, can provide technical support for short-circuit current stress to the power device 40, wherein the first DC power supply U1 can provide a DC supply voltage, the first capacitor C1 plays a role of voltage stabilization, and can stabilize the voltage between the first pole and the second pole of the power device 40, and the first resistor R1 plays a protective role, which can improve the stability and reliability of the circuit.

[0086] In one embodiment, Figure 5 As shown, the transient extreme stress loading circuit 22 includes an avalanche stress loading module 222 , and the avalanche stress loading module 222 is used to provide avalanche stress to the power device 40 .

[0087] The avalanche stress loading module 222 includes a second capacitor C2, a first inductor L1 and a second DC power supply U2. The first end of the second capacitor C2 is respectively connected to the first end of the first inductor L1 and the first end of the second DC power supply U2, the second end of the second capacitor C2 is respectively connected to the first pole of the power device 40 and the second end of the second DC power supply U2, the second end of the second capacitor C2 is grounded, the second end of the first inductor L1 is connected to the second pole of the power device 40, and the control end of the second DC power supply U2 is connected to the control circuit 23. Taking the power device 40 as a gallium nitride device as an example, the first pole of the power device 40 can be a source, and the second pole of the power device 40 can be a drain.

[0088] Wherein, the second DC power supply U2 can be a high-voltage DC power supply, and the second DC power supply U2 is used to provide a DC voltage. The specific value of the DC voltage can be set accordingly according to the test requirements of the power device 40 being applied with avalanche stress, and no excessive restrictions are made here. Wherein, the first inductor L1 can be understood as a load inductor, and can be connected to the power device 40, the second capacitor C2, and the second DC power supply U2 respectively through cold pressing terminals. The second DC power supply U2 can be the same high-voltage DC power supply as the aforementioned first DC power supply U1.

[0089] Exemplarily, the gate driving circuit 21 includes a second gate driving module 212, and the second gate driving module 212 is configured to provide a second gate driving signal to the gate of the power device 40. The second gate driving module 212 may include a second gate driver 2121 and a second protection resistor Rg2. Wherein, the first end of the second gate driver 2121 is connected to the gate of the power device 40 through the second protection resistor Rg2, and the second end of the second gate driver 2121 is connected to the first pole of the power device 40 and grounded.

[0090] The second gate driver 2121 is configured to generate a second gate driving signal. Exemplarily, the second gate driving signal may be a square wave signal. For example, the high level of the second gate driving signal is 5V, and the low level of the initial driving signal is 0V. In the application, the second gate driving signal can be set according to the avalanche stress test requirements of the power device 40. For illustrative purposes here, it can also be any other suitable signal, and no excessive limitation is made.

[0091] Exemplarily, the semiconductor parameter analyzer 30 includes a screw coil. The screw coil can be connected in series between the second pole of the power device 40 and the first inductor L1, and the screw coil can be used to measure the current flowing through the second pole of the power device 40. For example, if the power device 40 is a gallium nitride device, the screw coil can be used to measure the drain current Id of the power device 40. In another example, the semiconductor parameter analyzer 30 includes an avalanche tolerance tester 34. The avalanche tolerance tester 34 can be connected to the power device 40, and the avalanche tolerance tester 34 can be used to measure the avalanche breakdown characteristics of the power device 40. In yet another example, the semiconductor parameter analyzer 30 may include an oscilloscope 33. The oscilloscope 33 can be respectively connected to the gate, the first pole, and the second pole of the power device 40, and can be used to measure the voltage and current of the power device 40. For example, taking the power device 40 as a gallium nitride device as an example, the first pole of the power device 40 can be the source electrode, and the second pole of the power device 40 can be the drain electrode, then the oscilloscope 33 can be used to measure the drain-source voltage Vds.

[0092] The above-mentioned avalanche stress loading module 222, through the second capacitor C2, the first inductor L1, and the second DC power supply U2, in combination with the second gate driving module 212, can provide technical support for providing avalanche stress to the power device 40. Among them, the second DC power supply U2 can provide a DC supply voltage, the second capacitor C2 plays a voltage stabilizing role and can stabilize the voltage between the first pole and the second pole of the power device 40, and the first inductor L1 plays a protective role and can improve the stability and reliability of the circuit.

[0093] In one embodiment, as Figure 6As shown, the transient extreme stress loading circuit 22 includes a surge current stress loading module 223, and the surge current stress loading module 223 is used to provide surge current stress to the power device 40.

[0094] Among them, the surge current stress loading module 223 includes a rectifier bridge 2231, a switching transistor 2232, and a second inductor L2. Among them, the first end of the rectifier bridge 2231 is connected to the first pole of the switching transistor 2232, the second end of the rectifier bridge 2231 is connected to the second pole of the power device 40, and the second end of the rectifier bridge 2231 is grounded. The control end of the rectifier bridge 2231 is connected to the control circuit 23. The second pole of the switching transistor 2232 is connected to the first pole of the power device 40 through the second inductor L2, and the gate of the switching transistor 2232 is connected to the gate driving circuit 21.

[0095] The rectifier bridge 2231 is used to provide a direct current signal. Exemplarily, the rectifier bridge 2231 includes an AC source AC, a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4. Among them, the first end of the AC source AC is respectively connected to the anode of the first diode D1 and the cathode of the second diode D2, and the second end of the AC source AC is respectively connected to the anode of the third diode D3 and the cathode of the fourth diode D4. The cathode of the first diode D1 is respectively connected to the cathode of the third diode D3 and the first pole of the switching transistor 2232. The cathode of the second diode D2 is connected to the cathode of the fourth diode D4 and grounded.

[0096] Exemplarily, the surge current stress loading module 223 may further include a third inductor L3, a second resistor R2, and a third resistor R3. Among them, the first end of the rectifier bridge 2231 is connected to the first pole of the switching transistor 2232 through the series-connected third inductor L3 and second resistor R2, and the second pole of the power device 40 is grounded through the third resistor R3. Among them, the third inductor L3 can be understood as a parasitic inductor, and the second resistor R2 can be used to adjust the surge current. The third resistor R3 can be understood as a sampling resistor and can be used to detect the current flowing through the power device 40, such as the drain current Id.

[0097] Exemplarily, the gate driving circuit 21 includes a third gate driving module 213. The third gate driving module 213 is configured to provide a third gate driving signal to the gate of the power device 40 and a fourth gate driving signal to the switching transistor 2232. The third gate driving module 213 may include a third gate driver 2131, a third protection resistor Rg3, and a fourth gate driver 2132. Among them, the second gate driver 2121 is connected to the gate of the power device 40 through the third protection resistor Rg3, and the second gate driver 2121 is configured to generate a third gate driving signal according to the received first control signal. The fourth gate driver 2132 is connected to the gate of the switching transistor 2232, and the fourth gate driver 2132 is configured to generate a fourth gate driving signal according to the received second control signal. Wherein, the third gate driving signal is used to control the on / off state of the power device 40, and the fourth gate driving signal is used to control the on / off state of the switching transistor 2232. In application, the third gate driving signal and the fourth gate driving signal can be respectively set according to the surge current stress test requirements of the power device 40, and no further limitation is made here.

[0098] The above-mentioned surge current stress loading module 223, through the rectifier bridge 2231, the switching transistor 2232, and the second inductor L2, in combination with the third gate driving module 213, can provide technical support for providing surge current stress to the power device 40. Among them, the rectifier bridge 2231 can provide a DC signal, that is, a DC supply voltage. The switching transistor 2232 can control the on / off state of the path between the rectifier bridge 2231 and the power device 40 to achieve accurate and effective control of applying surge current stress to the power device 40. The second inductor L2 can improve the stability and reliability of the circuit.

[0099] Please continue to refer to Figure 2 , in one embodiment, the transient extreme stress loading circuit 22 includes a gating module 224, a short-circuit current stress loading module 221, an avalanche stress loading module 222, and a surge current stress loading module 223. Among them, the first end of the gating module 224 is connected to the second pole of the power device 40, and the three second ends of the gating module 224 are respectively grounded through the short-circuit current stress loading module 221, the avalanche stress loading module 222, and the surge current stress loading module 223. The control end of the gating module 224 is connected to the control circuit 23, and the gating module 224 is configured to select and conduct the paths between the short-circuit current stress loading module 221, the avalanche stress loading module 222, and the surge current stress loading module 223 and the power device 40 respectively under the control of the control circuit 23. Exemplarily, the gating module 224 can be a single-pole triple-throw switch. In this way, by controlling the on / off state of the gating module 224, the type switching of applying transient extreme stress to the power device 40 can be achieved, improving the flexibility and operability of the system.

[0100] In one embodiment, as Figure 2 and Figure 7 shown, the high-power microwave irradiation device 10 includes a resonant cavity 11, a high-power microwave radiation source 12, and an excitation probe 13. Among them, the high-power microwave radiation source 12 is used to provide a high-power microwave signal. The power and frequency of the high-power microwave signal can be set accordingly according to the test requirements.

[0101] The resonant cavity 11 refers to a structure that can store electromagnetic wave energy at a specific frequency. The design of the resonant cavity 11 can determine its resonant frequency by precisely controlling its size and shape. Exemplarily, the resonant cavity 11 is a cavity enclosed by multiple irregular surfaces. For example, the resonant cavity 11 is a cavity formed by removing a wedge-shaped structure from one side of a cuboid. Exemplarily, the frequency of the high-power microwave signal is 2.45 GHz. In some other examples, the frequency of the high-power microwave signal can also be other values, such as 2.35 GHz, 2.4 GHz, 2.5 GHz, 2.55 GHz, etc., which are not limited here. The power device 40 is arranged in the resonant cavity 11. The position of the power device 40 can be set accordingly according to the position of the high-power microwave irradiation stress generated by the resonant cavity 11, which is not limited here.

[0102] The excitation probe 13 is arranged in the resonant cavity 11. Among them, the excitation probe 13 and the power device 40 are arranged at intervals in the resonant cavity 11. The excitation probe 13 is connected to the high-power microwave radiation source 12. The excitation probe 13 is used to generate resonance in the resonant cavity 11 according to the high-power microwave signal and provide high-power microwave irradiation stress to the power device 40. In application, the high-power microwave signal generated by the high-power microwave radiation source 12 is transmitted to the excitation probe 13 and generates an electromagnetic field through resonance in the resonant cavity 11. This electromagnetic field is used to simulate the high-power microwave irradiation stress.

[0103] In the power device degradation effect on-line evaluation system provided by the above embodiment, the high-power microwave irradiation device 10 includes a resonant cavity 11, a high-power microwave radiation source 12, and an excitation probe 13. By respectively arranging the power device 40 and the excitation probe 13 in the resonant cavity 11, and providing a high-power microwave signal through the high-power microwave radiation source 12, and generating resonance in the resonant cavity 11 according to the high-power microwave signal by the excitation probe 13 and providing high-power microwave irradiation stress to the power device 40. In this way, through the combination of the resonant cavity 11, the high-power microwave radiation source 12, and the excitation probe 13, precise control of the high-power microwave irradiation stress can be achieved, including but not limited to parameters such as irradiation power and irradiation time, ensuring the stability and repeatability of the test conditions, providing a test and evaluation platform for the on-line evaluation of the degradation effect of the power device 40 in different application scenarios, and providing technical support and data support for in-depth research on the performance evolution of the power device 40 in a complex electromagnetic environment, improving the reliability of the system.

[0104] As Figure 7 shown, in one embodiment, the high-power microwave radiation source 12 includes a microwave signal source 121, a power amplifier 122, a circulator 123, and a directional coupler 124.

[0105] Among them, the microwave signal source 121 is used to provide microwave signals. Exemplarily, the microwave signal source 121 can be used to provide microwave signals with adjustable power and / or adjustable frequency. In applications, for different types of power devices 40 and different high-power microwave irradiation test requirements, the microwave signal generated by the microwave signal source 121 can be controlled through the microwave signal source 121. In this way, precise regulation can be carried out for different types of power devices 40 and their test conditions, improving the controllability and flexibility of the system.

[0106] The power amplifier 122 is connected to the microwave signal source 121. Among them, the input end of the power amplifier 122 is connected to the microwave signal source 121. The power amplifier 122 is used to perform power amplification processing on the microwave signal from the microwave signal source 121 and output a high-power microwave signal. The power amplifier 122 is designed to amplify the power of the microwave signal to reach the high-power level required for testing. In this way, the power requirement for the microwave signal is reduced, that is, even if the power of the microwave signal is low, a high-power microwave irradiation test environment can be provided, which not only improves the flexibility of the system but also ensures the effective utilization of energy during the test.

[0107] The circulator 123 is respectively connected to the power amplifier 122 and the directional coupler 124. The input end of the circulator 123 is connected to the output end of the power amplifier 122, and the output end of the circulator 123 is connected to the input end of the directional coupler 124. The circulator 123 is used to transmit the high-power microwave signal from the power amplifier 122 to the directional coupler 124. The circulator 123 can unidirectionally transmit the high-power microwave signal from the power amplifier 122 to the directional coupler 124, and at the same time provide necessary isolation protection to prevent reverse signals from damaging sensitive components (such as the microwave signal source 121). In this way, unnecessary interference and losses can be effectively avoided, ensuring the best performance of the signal transmission path.

[0108] The directional coupler 124 is connected to the excitation probe 13. Among them, the DC output end of the directional coupler 124 is connected to the excitation probe 13. The directional coupler 124 is used to transmit the high-power microwave signal from the circulator 123 to the excitation probe 13. The directional coupler 124 helps to monitor and adjust the test process in real time, providing a stable and controllable irradiation stress for the power device 40, thereby improving the reliability and stability of the test results.

[0109] In the on-line evaluation system for the degradation effect of the power device provided by the above embodiments, the high-power microwave radiation source 12 includes a microwave signal source 121, a power amplifier 122, a circulator 123, and a directional coupler 124. The system provides a microwave signal through the microwave signal source 121, performs power amplification processing on the microwave signal from the microwave signal source 121 through the power amplifier 122, and outputs a high-power microwave signal. The high-power microwave signal from the power amplifier 122 is transmitted to the directional coupler 124 through the circulator 123, and the high-power microwave signal from the circulator 123 is transmitted to the excitation probe 13 through the directional coupler 124, so as to be able to provide a high-power microwave signal to provide high-power microwave irradiation stress to the power device 40. In this way, the efficient and accurate test of the power device 40 under high-power microwave irradiation conditions is realized, which is also helpful to improve the technical level of the entire test platform and provides strong support for evaluating and improving the long-term reliability of the power device 40.

[0110] Please continue to refer to Figure 7 , in one embodiment, the on-line evaluation system for the degradation effect of the power device further includes a power meter 50. Among them, the directional coupler 124 includes a first directional coupler 1241 and a second directional coupler 1242.

[0111] The input end of the first directional coupler 1241 is connected to the circulator 123. The input end of the first directional coupler 1241 can receive the high-power microwave signal from the circulator 123. The through output end of the first directional coupler 1241 is connected to the input end of the second directional coupler 1242. The through output end of the first directional coupler 1241 can transmit the high-power microwave signal from the circulator 123 to the second directional coupler 1242. The coupled output end of the first directional coupler 1241 is connected to the first end CH1 of the power meter 50. The first directional coupler 1241 can couple the high-power microwave signal from the circulator 123 and output the first power through the coupled output end.

[0112] The input end of the second directional coupler 1242 can receive the high-power microwave signal from the first directional coupler 1241. The DC output end of the second directional coupler 1242 is connected to the excitation probe 13. The through output end of the second directional coupler 1242 can transmit the high-power microwave signal from the first directional coupler 1241 to the excitation probe 13. The coupled output end of the second directional coupler 1242 is connected to the second end CH2 of the power meter 50. The second directional coupler 1242 can couple the high-power microwave signal from the first directional coupler 1241 and output the second power through the coupled output end.

[0113] The power meter 50 is used to detect the first power coupled and output by the first directional coupler 1241 and the second power coupled and output by the second directional coupler 1242. Among them, the first power coupled and output by the first directional coupler 1241 can be understood as the input power, and the second power coupled and output by the second directional coupler 1242 can be understood as the reflected power.

[0114] In the application, the power difference between the first power and the second power can be calculated, and whether the high-power microwave irradiation device 10 provides stable high-power microwave irradiation stress can be judged according to the power difference. Exemplarily, if the absolute value of the power difference between the first power and the second power is greater than or equal to 20 dBm, it is determined that the high-power microwave irradiation device 10 provides stable high-power microwave irradiation stress. In this way, the input power and the reflected power of the high-power microwave signal source 121 can be detected in real time by the power meter 50, the real-time detection of the high-power microwave irradiation stress can be realized, and stable high-power microwave irradiation stress can be ensured for the power device 40.

[0115] As Figure 8 shown, in one embodiment, the online evaluation system for the power device degradation effect further includes a device fixture 60. The device fixture 60 includes a fixture body 61 and signal terminals 62. Among them, the fixture body 61 is used to carry the power device 40. The power device 40 can be arranged on one side of the fixture body 61. In this way, the power device 40 can be placed in the high-power microwave irradiation device 10 through the fixture body 61 of the device fixture 60 to apply high-power microwave irradiation stress to the power device 40.

[0116] The signal terminals 62 are located on the side of the fixture body 61 away from the power device 40. The signal terminals 62 are arranged outside the high-power microwave irradiation device 10. The signal terminals 62 are used to be connected to the power device 40, the transient extreme stress loading device 20 and the semiconductor parameter analyzer 30 respectively. In this way, the connection between the power device 40 and the transient extreme stress loading device 20 and the semiconductor parameter analyzer 30 can be realized through the signal terminals 62 of the device fixture 60, the connection difficulty between devices is reduced, and technical support is provided for testing the degradation characteristics of the power device 40 under the combined stress, namely high-power microwave irradiation stress and transient extreme stress.

[0117] Exemplarily, the signal terminals 62 include at least three signal terminals 62. For example, the device fixture 60 includes three signal terminals 62, namely the gate signal terminal G, the source signal terminal S, and the drain signal terminal D respectively. Taking the power device 40 as a gallium nitride device as an example, the gate signal terminal S is connected to the gate of the gallium nitride device, the source signal terminal S is connected to the source of the gallium nitride device, and the drain signal terminal D is connected to the drain of the gallium nitride device. Moreover, the three signal terminals 62 are respectively connected to the transient extreme stress loading device 20 and the semiconductor parameter analyzer 30. Also, the number of the signal terminals 62 can be four or more, which can be specifically set according to the test requirements and will not be further limited herein.

[0118] One side of the fixture body 61 close to the power device 40 is arranged inside the high-power microwave irradiation device 10. One side of the fixture body 61 close to the signal terminals 62 is arranged outside the high-power microwave irradiation device 10. Exemplarily, the fixture body 61 includes a first fixture body 611 and a second fixture body 612 located on one side of the first fixture body 611. Among them, the side of the second fixture body 612 away from the first fixture body 611 is used to carry the power device 40, and the second fixture body 612 can be arranged inside the high-power microwave irradiation device 10. Signal terminals 62 are arranged on the side of the first fixture body 611 away from the second fixture body 612, and the second fixture body 612 can be arranged outside the high-power microwave irradiation device 10. Exemplarily, the projection of the second fixture body 612 in the direction from the first fixture body 611 to the power device 40 covers the first fixture body 611. In this way, by arranging the first fixture body 611 and the second fixture body 612, the signal terminals 62 can be arranged outside the high-power microwave irradiation device 10 through the first fixture body 611, and the power device 40 can be arranged inside the high-power microwave irradiation device 10 through the second fixture body 612, thereby providing support for the test and improving the reliability of the system.

[0119] Based on the same inventive concept, an embodiment of the present application provides a method for online evaluation of the degradation effect of power devices. This method can be applied to the power device degradation effect online evaluation system provided in any of the foregoing embodiments. The implementation solutions for solving problems provided by this method are similar to the implementation solutions recorded in the above system. Therefore, the specific limitations in one or more embodiments of the method for online evaluation of the degradation effect of power devices provided below can refer to the limitations on the power device degradation effect online evaluation system in the foregoing text and will not be elaborated herein.

[0120] Combined with Figures 1 to 8 , as Figure 9 shown, a method for online evaluation of the degradation effect of power devices is provided, and this method includes the following steps S902 to step S908.

[0121] S902: Obtain the initial electrical parameters of the power device.

[0122] In the application, the semiconductor parameter analyzer 30 can be connected to the power device 40, and before applying high-power microwave irradiation stress to the power device 40 and when the power device 40 is in the off state, the semiconductor parameter analyzer 30 is used to obtain the initial electrical parameters of the power device 40. For the specific introduction of the semiconductor parameter analyzer 30 and the initial electrical parameters, please refer to the relevant content above and will not be elaborated here.

[0123] S904: Apply high-power microwave irradiation stress and transient extreme stress to the power device.

[0124] In the application, the high-power microwave irradiation device 10 can be used to apply high-power microwave irradiation stress to the power device 40, and the transient extreme stress loading device 20 is used to apply transient extreme stress to the power device 40. For the specific introduction of the high-power microwave irradiation device 10 and the transient extreme stress loading device 20, please refer to the relevant content above and will not be elaborated here.

[0125] S906: Obtain the test electrical parameters of the power device when it is applied with high-power microwave irradiation stress and transient extreme stress.

[0126] In the application, the semiconductor parameter analyzer 30 can be used to obtain the test electrical parameters of the power device 40 when it is applied with high-power microwave irradiation stress and transient extreme stress.

[0127] S908: Obtain the online evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters.

[0128] In the application, the semiconductor parameter analyzer 30 can be used to determine the online evaluation result of the degradation effect of the power device 40 according to the initial electrical parameters and the test electrical parameters.

[0129] For the above online evaluation method of the power device degradation effect, the initial electrical parameters of the power device 40 are obtained, high-power microwave irradiation stress and transient extreme stress are applied to the power device 40, the test electrical parameters of the power device 40 when it is applied with high-power microwave irradiation stress and transient extreme stress are obtained, and the online evaluation result of the degradation effect of the power device 40 is determined according to the initial electrical parameters and the test electrical parameters. This method realizes the degradation test of the power device 40 when it is applied with high-power microwave irradiation stress and transient extreme stress, and can accurately evaluate the electrical parameter degradation characteristics of the power device 40 under transient extreme working conditions when it bears high-power microwave irradiation stress, thus providing strong technical support and data support for the reliability research and protection design of the power device 40 in the high-power microwave irradiation environment, and has broad application prospects.

[0130] In one embodiment, in step S908, an online evaluation result of the degradation effect of the power device is obtained based on the initial electrical parameters and the test electrical parameters, including: determining whether the power device fails according to the initial electrical parameters and the test electrical parameters; in the case where the power device does not fail, adjusting the high-power microwave irradiation stress and / or the transient extreme stress, and re-executing the step of obtaining the test electrical parameters of the power device subjected to the high-power microwave irradiation stress and the transient extreme stress; in the case where the power device fails, obtaining the online evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters, and the online evaluation result is used to characterize the failure condition of the power device.

[0131] It can be understood that when the power device 40 bears the high-power microwave stress and the transient extreme stress at the same time, the power device 40 is more likely to degenerate and even fail. In this regard, in the application, it can be determined whether the power device 40 fails according to the initial electrical parameters and the test electrical parameters. If the power device 40 does not fail, it indicates that the power device 40 can still be used as the device under test. In this case, an online evaluation result of the degradation effect of the power device 40 can be obtained according to the initial electrical parameters and the test electrical parameters. This online evaluation result is used to represent the degradation condition of the power device 40, or rather, the degradation degree of the power device 40; and, the high-power stress can be adjusted, and / or, the transient extreme stress can be adjusted, and the test electrical parameters of the power device 40 subjected to the adjusted high-power microwave stress and the transient extreme stress can be obtained, and a new online evaluation result of the degradation effect can be obtained according to the initial electrical parameters and the test electrical parameters, so as to provide more test data for the degradation characteristics of the power device 40. If the power device 40 fails, it indicates that the power device 40 is damaged. In this case, the power device 40 cannot continue to be used as the device under test for testing. In this regard, failure analysis can be performed according to the initial electrical parameters and the test electrical parameters, and an online evaluation result can be obtained, and this online evaluation result can characterize the failure condition of the power device 40.

[0132] The above online evaluation method for the degradation effect of power devices determines whether the power device 40 fails according to the initial electrical parameters and the test electrical parameters. When the power device 40 does not fail, the high-power microwave irradiation stress and / or the transient extreme stress are adjusted, and the step of obtaining the test electrical parameters of the power device 40 subjected to the high-power microwave irradiation stress and the transient extreme stress is performed again. When the power device 40 fails, the online evaluation result of the degradation effect of the power device 40 is obtained according to the initial electrical parameters and the test electrical parameters. This online evaluation result is used to characterize the failure condition of the power device 40. In this way, by judging the failure of the power device 40, the test stress can be adjusted to obtain more comprehensive test data when it does not fail, which helps to reduce the test cost. And when it fails, failure analysis can be carried out and the corresponding failure analysis characterization can be obtained, providing technical support and data support for the failure characteristics of the power device 40 after being subjected to the high-power microwave irradiation stress and the transient extreme stress, so as to guide the design and application of the power device 40.

[0133] In one embodiment, step S904 of applying the high-power microwave irradiation stress and the transient extreme stress to the power device includes: obtaining the test condition parameters of the power device, and applying the high-power microwave irradiation stress and the transient extreme stress to the power device according to the test condition parameters. Among them, the test condition parameters include the high-power microwave irradiation condition parameters and the transient extreme stress condition parameters. The high-power microwave irradiation condition parameters are used to represent the relevant parameters for applying the high-power microwave irradiation stress to the power device. For example, the high-power microwave irradiation condition parameters may include the irradiation power and the irradiation time. Among them, the irradiation power refers to the power of the high-power microwave irradiation stress, and the irradiation time refers to the duration of applying the high-power microwave irradiation stress to the power device. The transient extreme stress condition parameters are used to represent the relevant parameters for applying the transient extreme stress to the power device. For example, the transient extreme stress condition parameters may include the type of transient extreme stress, the switching frequency, the duty cycle, etc.

[0134] The online evaluation method for the degradation effect of the power device provided in the above embodiment obtains the test condition parameters of the power device 40, and applies the high-power microwave irradiation stress and the transient extreme stress to the power device 40 according to the test condition parameters. In this way, the test parameters can be accurately controlled according to the test requirements, such as the irradiation power, the irradiation time, and the type of transient extreme stress, etc., to realize the accurate test and evaluation of the electrical parameter degradation characteristics of the power device 40 when it is subjected to the high-power microwave irradiation stress under different transient extreme working conditions, so as to meet various test requirements and provide sufficient data support.

[0135] Please continue to refer to Figures 1 to 8 In one embodiment, an online evaluation method for the degradation effect of a power device is provided, and this method is applied to an online evaluation system for the degradation effect of a power device.

[0136] The system includes a high-power microwave irradiation device 10, a semiconductor parameter analyzer 30, a high-voltage DC power supply, an auxiliary power supply, an FPGA microcontroller, a transient extreme stress loading device 20, control signal cables, power supply cables, test cables, a device fixture 60, a test socket, and a power meter 50.

[0137] The high-power microwave irradiation device 10 applies high-power microwave irradiation stress to the power device 40 through the device fixture 60. The power device 40 is connected to the transient extreme stress loading device 20 through the test socket. The semiconductor parameter analyzer 30 is connected to the power device 40 through the test cable. The high-voltage DC power supply and the auxiliary power supply are connected to the transient extreme stress loading device 20 through the power supply cable. The FPGA microcontroller is connected to the transient extreme stress loading device 20 through the control signal cable.

[0138] The high-power microwave irradiation device 10 includes a microwave signal generator 2111, a solid-state power amplifier 122, a directional coupler 124, a circulator 123, a resonant cavity 11, an excitation probe 13, and a coaxial cable. Among them, the resonant cavity 11 applies high-power microwave irradiation stress to the power device 40 through the device fixture 60. The microwave signal generator 2111, the solid-state power amplifier 122, the directional coupler 124, and the circulator 123 are connected together through the coaxial cable, and their function is to amplify the microwave signal and inject it into the excitation probe 13, and finally generate high-power microwave irradiation stress in the resonant cavity 11. And, the directional coupler 124 is connected to the power meter 50. For its specific structure and introduction, reference can be made to Figure 2 and Figure 7 the relevant content above, which will not be elaborated here.

[0139] The transient extreme stress loading device 20 includes a gate drive circuit 21, a control circuit 23, and a transient extreme stress loading circuit 22. For its specific structure, reference can be made to Figures 1 to 6 the relevant content above, which will not be elaborated here.

[0140] As Figure 10 shown, the online evaluation method for the degradation effect of the power device includes the following steps S1002 to step S1022.

[0141] S1002: Obtain the test condition parameters of the power device, set the power and frequency of the microwave signal source, and connect the microwave signal source, the solid-state power amplifier, the directional coupler, the circulator, the resonant cavity, and the excitation probe through the coaxial cable. Among them, the frequency of the microwave signal source 121 can be set to 2.45 GHz.

[0142] S1004: Set the FPGA controller according to the test condition parameters to set the switching frequency, duty cycle, and target operating state of the power device, and connect the FPGA controller to the corresponding signal port on the transient extreme stress loading device through a control cable. At the same time, connect the auxiliary power supply and the high-voltage DC power supply to the corresponding circuits respectively.

[0143] In the application, the switching frequency, duty cycle, and transient extreme stress mode and conditions of the power device 40 can be set by writing a corresponding computer program such as a Verilog HDL program and downloading it to the FPGA controller, so as to realize the setting of transient extreme stress.

[0144] S1006: Set the semiconductor parameter analyzer according to the test condition parameters.

[0145] In the application, the required test curves can be programmed on the semiconductor parameter analyzer 30.

[0146] S1008: Place the power device in the radiation cavity through the device fixture.

[0147] S1010: Connect the pins of the power device to the transient extreme stress loading device and the semiconductor parameter analyzer respectively through the signal terminals on the device fixture.

[0148] S1012: Turn on the semiconductor parameter analyzer to test the initial parameters of the power device and obtain the initial electrical parameters of the power device.

[0149] S1014: Turn on the output button of the microwave signal source to apply high-power microwave irradiation stress to the power device.

[0150] S1016: Turn on the auxiliary power supply, turn on the high-voltage DC power supply after the gate drive circuit works normally, and after the power supply is stable, apply transient extreme stress to the power device through the FPGA control signal. Among them, the transient extreme stress can include short-circuit current stress, avalanche stress or surge current stress.

[0151] S1018: After the power device works for the preset irradiation time, turn off the microwave signal source, stop applying high-power microwave irradiation stress, and turn off the high-voltage source and the auxiliary power supply, and the power device stops working.

[0152] S1020: Turn on the semiconductor parameter analyzer to conduct parameter tests and obtain the test electrical parameters of the power device.

[0153] S1022: After the parameter test is completed, export the experimental data. The test data includes the online evaluation results of the degradation effect of the power device.

[0154] Such as Figure 11As shown, in the application, the initial electrical parameters of the power device 40 can be obtained through the semiconductor parameter analyzer 30 first, and then the test condition parameters of the power device 40 are obtained. The high-power microwave conditions are set according to the test condition parameters, and the device steady-state bias is adjusted. In addition, the transient extreme stress mode is selected, and the transient extreme stress conditions are set, so as to apply a combined stress, namely high-power microwave irradiation stress and transient extreme stress, to the power device 40. Then, the test electrical parameters after the combined stress is applied during the power period are obtained, and it is determined whether the power device 40 fails according to the initial electrical parameters and the test electrical parameters. If so, device failure analysis and characterization are carried out; if not, degradation analysis is carried out, test data are obtained, and the high-power microwave radiation conditions and / or transient extreme stress conditions are adjusted, and then the adjusted combined stress is applied to the power device 40 again to obtain more test data.

[0155] The above online evaluation system and method for the degradation effect of power devices organically combines the high-power microwave radiation device, the transient extreme stress loading device 20 and the semiconductor parameter analyzer 30, and realizes the accurate evaluation of the degradation effect of the power device 40 under complex working conditions. By combining high-power microwave with transient extreme stress, the system can be closer to the actual working conditions, and comprehensively analyze and evaluate the degradation behavior and its mechanism of the power device 40 under the above working conditions based on the change of electrical parameters. Moreover, the present application can accurately control the power and time of high-power microwave radiation, and can realize a variety of transient extreme stress tests, including short circuit, avalanche, surge, etc. On this basis, the electrical parameters of the device are tested and characterized by the semiconductor parameter analyzer 30, so as to realize the evaluation of the device degradation effect, and high-power microwave radiation can be applied in real time under the condition that the device experiences transient stress without causing additional influence on the test circuit. In addition, the system is applicable to a variety of power devices 40, including silicon, silicon carbide, gallium nitride, etc., and can provide reliability verification and performance improvement support for the devices widely used at present stage. It not only provides new suggestions and references for improving the reliability of the power device 40, but also provides strong experimental support for the high-power microwave protection of the power supply module and the electric drive module of the unmanned aerial vehicle, and has good application potential and broad market prospects.

[0156] In the description of this specification, the descriptions referring to the terms "some embodiments", "other embodiments", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0157] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0158] The above-described embodiments merely represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation to the scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several variations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the appended claims.

Claims

1. An online evaluation system for the degradation effect of a power device, characterized in that, Comprising: A high-power microwave irradiation device, a transient extreme stress loading device, and a semiconductor parameter analyzer; the power device is disposed within the high-power microwave irradiation device and is respectively connected to the transient extreme stress loading device and the semiconductor parameter analyzer; wherein, The high-power microwave irradiation device is configured to provide high-power microwave irradiation stress to the power device; The transient extreme stress loading device is configured to provide transient extreme stress to the power device; The semiconductor parameter analyzer is configured to obtain the initial electrical parameters of the power device, obtain the test electrical parameters of the power device when the high-power microwave irradiation stress and the transient extreme stress are applied thereto, and determine an online evaluation result of the degradation effect of the power device based on the initial electrical parameters and the test electrical parameters.

2. The system according to claim 1, characterized in that, The transient extreme stress loading device includes: A gate drive circuit connected to the gate of the power device for providing a gate drive signal; A transient extreme stress loading circuit respectively connected to the first and second electrodes of the power device for providing the transient extreme stress; the transient extreme stress includes at least one of short-circuit current stress, avalanche stress, and surge current stress; A control circuit respectively connected to the gate drive circuit and the transient extreme stress loading circuit for controlling the working states of the gate drive circuit and the transient extreme stress loading circuit to provide the transient extreme stress to the power device.

3. The system according to claim 2, wherein The transient extreme stress loading circuit includes a short-circuit current stress loading module for providing the short-circuit current stress to the power device; wherein, The short-circuit current stress loading module includes a first capacitor, a first resistor, and a first DC power supply; a first end of the first capacitor is respectively connected to a first end of the first resistor and the second electrode of the power device, a second end of the first capacitor is connected to the first electrode of the power device, and the second end of the first capacitor is grounded, a second end of the first resistor is grounded through the first DC power supply, and a control end of the first DC power supply is connected to the control circuit.

4. The system according to claim 2, wherein The transient extreme stress loading circuit includes an avalanche stress loading module for providing the avalanche stress to the power device; wherein, The avalanche stress loading module includes a second capacitor, a first inductor, and a second DC power supply; a first end of the second capacitor is respectively connected to a first end of the first inductor and a first end of the second DC power supply, a second end of the second capacitor is respectively connected to the first electrode of the power device and a second end of the second DC power supply, the second end of the second capacitor is grounded, a second end of the first inductor is connected to the second electrode of the power device, and a control end of the second DC power supply is connected to the control circuit.

5. The system according to claim 2, characterized in that, The transient extreme stress loading circuit includes a surge current stress loading module for providing the surge current stress to the power device; wherein, The surge current stress loading module includes a rectifier bridge, a switching transistor, and a second inductor. Among them, the first end of the rectifier bridge is connected to the first pole of the switching transistor, the second end of the rectifier bridge is connected to the second pole of the power device, and the second end of the rectifier bridge is grounded. The control end of the rectifier bridge is connected to the control circuit. The second pole of the switching transistor is connected to the first pole of the power device through the second inductor, and the gate of the switching transistor is connected to the gate drive circuit.

6. The system according to any one of claims 1-5, characterized in that The high-power microwave irradiation device includes: A resonant cavity, where the power device is arranged in the resonant cavity; A high-power microwave radiation source for providing high-power microwave signals; An excitation probe arranged in the resonant cavity and connected to the high-power microwave radiation source, for generating resonance in the resonant cavity according to the high-power microwave signals and providing the high-power microwave irradiation stress to the power device.

7. The system according to claim 6, wherein The high-power microwave radiation source includes a microwave signal source, a power amplifier, a circulator, and a directional coupler. Among them, The microwave signal source is used for providing microwave signals; The power amplifier is connected to the microwave signal source, and the power amplifier is used for performing power amplification processing on the microwave signals and outputting high-power microwave signals; The circulator is respectively connected to the power amplifier and the directional coupler, and the circulator is used for transmitting the high-power microwave signals from the power amplifier to the directional coupler; The directional coupler is connected to the excitation probe, and the directional coupler is used for transmitting the high-power microwave signals from the circulator to the excitation probe.

8. An on-line evaluation method for the degradation effect of a power device, characterized in that, The method includes: Obtaining the initial electrical parameters of the power device; Applying high-power microwave irradiation stress and transient extreme stress to the power device; Obtaining the test electrical parameters of the power device when the high-power microwave irradiation stress and the transient extreme stress are applied to the power device; Obtaining an online evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters.

9. The method according to claim 8, characterized in that, The obtaining the online evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters includes: Judging whether the power device fails according to the initial electrical parameters and the test electrical parameters; When the power device does not fail, adjusting at least one of the high-power microwave irradiation stress and the transient extreme stress, and executing again the step of obtaining the test electrical parameters of the power device when the high-power microwave irradiation stress and the transient extreme stress are applied to the power device; When the power device fails, obtaining an online evaluation result of the degradation effect of the power device according to the initial electrical parameters and the test electrical parameters, and the online evaluation result is used for characterizing the failure condition of the power device.

10. The method according to claim 8, wherein Applying the high-power microwave irradiation stress and the transient extreme stress to the power device includes: Obtaining the test condition parameters of the power device; the test condition parameters include high-power microwave irradiation condition parameters and transient extreme stress condition parameters; Applying the high-power microwave irradiation stress and the transient extreme stress to the power device according to the test condition parameters.

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