CN115267466A - A test system for studying the characteristics of gallium nitride power devices under dynamic conditions - Google Patents

Abstract

The invention relates to a test system for characteristic research of gallium nitride power devices under dynamic working conditions. The test system is based on a comprehensive research environment model of dynamic resistance of gallium nitride power devices, including temperature, DC-link voltage, current, frequency, switching mode and pulse mode, etc., to investigate and study the switching characteristics and dynamic resistance characteristics of GaN power devices. Among them, the temperature-controlled heating unit can realize the investigation of the tested GaN power devices under different temperature scenarios; the adjustable DC‑ The link voltage can realize different DC-link voltages in the environment model; the load unit can make the tested GaN power device work in different current modes, switching modes, and pulse modes; the adjustable PWM signal is the upper and lower switching transistors Provides switching commands at different frequencies. The test system includes variables in a comprehensive GaN power device dynamic resistance research environment model, which can achieve the purpose of measuring and studying the dynamic working condition characteristics of GaN power devices under different combinations of operating conditions.

Description

A test system for researching the characteristics of GaN power devices under dynamic conditions

technical field

The invention belongs to the technical field of testing characteristics of gallium nitride power devices under dynamic working conditions, and in particular relates to a testing system for researching characteristics of gallium nitride power devices under dynamic working conditions.

Background technique

GaN power devices, with their low on-resistance, low parasitic capacitance and zero reverse recovery charge, have become one of the best candidates for next-generation high-frequency, high-efficiency, and high-power-density converters. There is a big gap between GaN power devices and traditional silicon power devices in terms of material growth, device structure and process manufacturing process. With the new application scenarios of faster switching speed, higher power and higher frequency of GaN power devices , so that this type of device exhibits brand-new dynamic operating characteristics different from silicon power devices under actual dynamic operating conditions. Although the development of GaN power devices has made some progress in recent years, a crucial problem that needs to be solved for the wide application of GaN power devices is the dynamic resistance (Rds,on ) degradation problem, which will not only cause additional energy loss of the power system, but also bring serious hidden dangers to the reliability of devices and even the power system. Based on the traditional silicon power device double-pulse test research method can no longer meet the measurement and research of key characteristic parameters such as dynamic resistance under the dynamic working conditions of GaN power devices, the new dynamic characteristic test technology and corresponding characterization methods of GaN power devices It has become an important force to promote the optimization design iteration of GaN power devices and the rapid development of a new generation of energy systems based on GaN power devices.

At present, only the static resistance (Ron) of the device is reported in the GaN power device handbook, which is measured under DC conditions and a relatively low source-drain voltage Vds, while the dynamic resistance of the actual GaN power device The characteristic is a variable determined by comprehensive environmental factors such as temperature, DC-link voltage, current, frequency, switching mode and pulse mode in the power supply condition. The improvement of the dynamic characteristics of GaN power device products and based on GaN The dynamic resistance characteristics of the power supply design of the power device are more practical and meaningful, but are not reported in the device manual. The actual working conditions (including temperature, DC-link voltage, current, frequency, switching mode and pulse The actual conduction loss corresponding to the dynamic resistance change of mode, etc.) is not well described.

At present, the measurement methods of dynamic resistance of GaN power devices under different working conditions at home and abroad are roughly divided into two categories: the first category is based on Agilent B1505A and other power component analyzers such as on-wafer single-pulse test or double-pulse test . Due to the limitation of this type of measuring instrument, such methods are usually unable to evaluate the dynamic resistance characteristics of GaN power devices under the real power supply conditions of high current and high voltage at the same time. The second category is to use the circuit-level double-pulse test method at room temperature to study the dynamic resistance characteristics of GaN power devices at different temperatures, and use this as a basis to estimate the corresponding power and frequency caused by the dynamic resistance change in the power system. The proportion of the power system loss in the total loss.

However, studies have confirmed that the dynamic resistance characteristics of GaN power devices are affected by comprehensive environmental factors such as temperature, DC-link voltage, current, frequency, switching mode, and pulse mode in actual power supply conditions. The traditional analysis of power components based on Agilent B1505A The single-pulse test or double-pulse test method of single voltage or current stress at the on-wafer level of the instrument, and the double-pulse test method at the circuit level are not enough to evaluate the dynamic resistance of GaN power devices under actual power conditions (including temperature, DC-link voltage, current, frequency, switching mode and pulse mode, etc.) in the application.

Contents of the invention

In order to solve the above-mentioned problems in the prior art, the present invention provides a test system for researching the characteristics of GaN power devices under dynamic working conditions. The technical problem to be solved in the present invention is realized through the following technical solutions:

The present invention provides a test system for researching characteristics of gallium nitride power devices under dynamic working conditions, including: a performance evaluation sub-board and a performance evaluation motherboard, wherein,

The performance evaluation motherboard includes several access ports for receiving input PWM signals, DC-link voltages and driving voltages, wherein both the PWM signals and the DC-link voltage can be adjusted; the performance evaluation sub-board The board is plugged into the performance evaluation motherboard to obtain the PWM signal, the DC-link voltage and the driving voltage;

The performance evaluation sub-board is provided with a test circuit module, and the test circuit module includes an upper switch tube drive unit, an upper switch tube, a lower switch tube drive unit, a lower switch tube, a temperature control heating unit, a load unit, and several measurement ports ,in,

The lower switching tube is a GaN power device to be tested; the upper switching tube and the lower switching tube are connected to form a half-bridge circuit; the DC-link voltage provides the working voltage required by the half-bridge circuit;

The upper switching tube driving unit is connected to the upper switching tube, and the upper switching tube driving unit controls the opening and closing of the upper switching tube according to the PWM signal; the lower switching tube driving unit is connected to the lower switching tube The switching tube is connected, and the lower switching tube drive unit controls the opening and closing of the lower switching tube according to the PWM signal;

The load unit is connected to the upper switch tube; the temperature-controlled heating unit is attached to the lower switch tube;

By adjusting the temperature-controlled heating unit, the load unit, the PWM signal and the DC-link voltage to obtain different combinations of test conditions, using several of the measurement ports to realize the measurement of the GaN power device under test Measurement of electrical characteristic parameters under different test condition combinations.

In one embodiment of the present invention, the upper switch transistor drive unit includes a connected power supply DC/DC circuit of the upper switch transistor drive unit and an upper switch transistor drive circuit, wherein,

The power supply DC/DC circuit of the upper switch tube drive unit provides the working voltage of the upper switch tube drive circuit;

The upper switch tube driving circuit is connected to the upper switch tube, and the upper switch tube drive circuit controls the upper switch tube to be turned on and off according to the PWM signal of the upper switch tube.

In one embodiment of the present invention, the lower switching tube driving unit includes a connected power supply DC/DC circuit of the lower switching tube driving unit and a lower switching tube driving circuit, wherein,

The power supply DC/DC circuit of the lower switching tube driving unit provides the working voltage of the lower switching tube driving circuit;

The lower switching tube driving circuit is connected to the lower switching tube, and the lower switching tube driving circuit controls the opening and closing of the lower switching tube according to the PWM signal of the lower switching tube.

In one embodiment of the present invention, the temperature control voltage of the temperature control heating unit is the driving voltage, and the temperature control heating unit is a heating resistor. By adjusting the resistance value of the heating resistor, different temperatures are provided. Test Conditions.

In one embodiment of the present invention, the load unit includes a first load subunit and a second load subunit, wherein,

The first load subunit includes a first inductor connected between the source and the drain of the upper switching transistor;

The second load subunit includes a second inductor, a first capacitor, and a first resistor, wherein the first end of the second inductor is connected to the source of the upper switching transistor, and the first capacitor and the first capacitor A resistor is connected in series between the second end of the second inductor and the drain of the upper switch;

When the first load subunit is connected to the upper switch tube, by adjusting the load of the first inductor, test conditions for different load currents in double pulse mode are provided;

When the second load subunit is connected to the upper switching tube, by adjusting the load of the second inductor and the first resistor, test conditions of different switching modes and different load current modes in the continuous charging mode are provided.

In an embodiment of the present invention, the test circuit module further includes a second capacitor and a voltage clamping circuit, wherein the second capacitor is connected between the upper switch tube and the lower switch tube, so The voltage clamping circuit is connected between the drain and the source of the lower switching tube.

In one embodiment of the present invention, the test system further includes an auxiliary low-voltage power supply connected to the corresponding access port of the performance evaluation motherboard, and the auxiliary low-voltage power supply is used to provide the drive Voltage.

In one embodiment of the present invention, the test system further includes an adjustable high-voltage direct-current voltage source, the adjustable high-voltage direct-current voltage source is connected to the corresponding access port of the performance evaluation motherboard, and the adjustable high-voltage The DC voltage source is used to provide the adjustable DC-link voltage.

In one embodiment of the present invention, the test system further includes a digital signal processing control board, the digital signal processing control board is connected to the corresponding access port of the performance evaluation motherboard, and the digital signal processing control board It is used to provide the adjustable PWM signal of the upper switching tube and the PWM signal of the lower switching tube.

Compared with prior art, the beneficial effect of the present invention is:

1. The test system for researching the characteristics of GaN power devices under dynamic working conditions of the present invention is based on a comprehensive environmental model for the research of dynamic resistance of GaN power devices, wherein the temperature-controlled heating unit can realize the measurement of the measured GaN power devices. Investigation under different temperature scenarios; the adjustable DC-link voltage can realize different DC-link voltages in the environmental model; the load unit can make the GaN power device under test work in different currents, switching modes, and pulse modes ;The adjustable PWM signal provides switching commands for switching tubes with different frequencies; the test system includes a comprehensive environment model variable for the research of dynamic resistance of GaN power devices, which can be used to measure and study GaN power devices under different combinations of working conditions Purpose of characteristics under dynamic conditions.

2. The test system for researching the characteristics of GaN power devices under dynamic working conditions of the present invention can provide an important reference for the calculation of actual device loss in actual power supply applications based on GaN power devices. Various environmental factors are flexible and adjustable, and the corresponding environmental factor combinations can be designed according to different research and test purposes, so as to realize the targeted measurement of the switching characteristics and dynamic resistance characteristics of the GaN power device under different dynamic conditions. Research.

3. The test system of the present invention for researching the characteristics of GaN power devices under dynamic working conditions can be flexibly expanded to the research field of thermoelectric comprehensive characteristics other than the electrical characteristics of GaN power devices. The DSP control board in the test system of the present invention can be triggered by the logic gate level signal (Transistor-Transistor Logic, TTL) of other test systems, and the test trigger signals of different test systems are synchronized, so as to expand the synchronous research under dynamic working conditions Applications of thermoelectric properties of gallium nitride power devices.

The above description is only an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, it can be implemented according to the contents of the description, and in order to make the above and other purposes, features and advantages of the present invention more obvious and understandable , the following preferred embodiments are specifically cited below, and are described in detail as follows in conjunction with the accompanying drawings.

Description of drawings

FIG. 1 is a schematic diagram of a comprehensive research environment model for dynamic resistance of GaN power devices provided by an embodiment of the present invention;

Fig. 2 is a schematic structural diagram of a test system for researching characteristics of a gallium nitride power device under dynamic working conditions provided by an embodiment of the present invention;

Fig. 3 is a schematic structural diagram of a performance evaluation motherboard provided by an embodiment of the present invention;

Fig. 4 is a schematic structural diagram of a performance evaluation sub-board provided by an embodiment of the present invention;

Fig. 5 is a schematic circuit connection diagram of a double pulse and continuous pulse mode provided by an embodiment of the present invention;

FIG. 6 is a test schematic diagram of a test system for researching characteristics of a GaN power device under dynamic working conditions provided by an embodiment of the present invention.

Detailed ways

In order to further explain the technical means and effects of the present invention to achieve the intended purpose of the invention, the test system for the research on the characteristics of a gallium nitride power device under dynamic working conditions according to the present invention is carried out in conjunction with the accompanying drawings and specific implementation methods. Detailed description.

The aforementioned and other technical contents, features and effects of the present invention can be clearly presented in the following detailed description of specific implementations with accompanying drawings. Through the description of specific embodiments, the technical means and effects of the present invention to achieve the intended purpose can be understood more deeply and specifically, but the accompanying drawings are only for reference and description, and are not used to explain the technical aspects of the present invention. program is limited.

Embodiment one

This embodiment provides a test system for researching the characteristics of GaN power devices under dynamic working conditions. The actual dynamic resistance characteristics of GaN power devices are affected by the temperature, DC-link voltage, current, Variables determined by comprehensive environmental factors such as frequency, switching mode, and pulse mode, the test system of this embodiment is based on a comprehensive environmental model of GaN power device dynamic resistance research, as shown in Figure 1. The comprehensive GaN power device Schematic diagram of the environmental model for dynamic resistance research. The environmental model includes temperature, DC-link voltage, current, frequency, switching mode and pulse mode, etc.

Please refer to Fig. 2-Fig. 4 in combination. Fig. 2 is a schematic structural diagram of a test system for researching the characteristics of a gallium nitride power device under dynamic working conditions provided by an embodiment of the present invention; Fig. 3 is a performance provided by an embodiment of the present invention Schematic diagram of the evaluation motherboard; FIG. 4 is a schematic diagram of the structure of a performance evaluation sub-board provided by an embodiment of the present invention. As shown in the figure, the test system for researching the characteristics of GaN power devices under dynamic working conditions in this embodiment includes a performance evaluation daughter board 100 and a performance evaluation motherboard 200, wherein the performance evaluation motherboard 200 includes several access ports ( not shown in the figure), is used to receive the input PWM signal, DC-link voltage and driving voltage, wherein both the PWM signal and the DC-link voltage can be adjusted. The performance evaluation sub-board 100 is plugged with the performance evaluation motherboard 200 to obtain PWM signal, DC-link voltage and driving voltage.

Further, the performance evaluation sub-board 100 is provided with a test circuit module, and the test circuit module includes an upper switch tube drive unit 310, an upper switch tube 320, a lower switch tube drive unit 330, a lower switch tube 340, a temperature control heating unit 350, a load Unit 360 and several measurement ports (not shown in the figure).

Wherein, the lower switching tube 340 is a GaN power device under test; the upper switching tube 320 and the lower switching tube 340 are connected to form a half-bridge circuit; the DC-link voltage provides the working voltage required by the half-bridge circuit.

It should be noted that the basic circuit of the test circuit module in this embodiment is a half-bridge circuit composed of the upper switching transistor 320 , the lower switching transistor 340 and the load unit 360 . If the upper switching tube 320 is replaced with a diode, the system can also be used for research on the dynamic working condition characteristics of the upper switching tube 320, and the conduction current of the upper switching tube 320 can be measured with a current sensor based on a ferrite core and a current probe.

Further, the upper switch tube drive unit 310 is connected with the upper switch tube 320, and the upper switch tube drive unit 310 controls the opening and closing of the upper switch tube 320 according to the corresponding PWM signal; the lower switch tube drive unit 330 is connected with the lower switch tube 340 , the lower switch transistor drive unit 340 controls the turn-on and turn-off of the lower switch transistor 340 according to the corresponding PWM signal. The load unit 360 is connected to the upper switching tube 320 ; the temperature-controlled heating unit 350 is attached to the lower switching tube 340 .

In this embodiment, different combinations of test conditions are obtained by adjusting the temperature-controlled heating unit 350, the load unit 360, the PWM signal and the DC-link voltage, and several measurement ports are used to realize the combination of different test conditions for the GaN power device under test. Under the electrical characteristic parameter measurement.

Further, the test principle of the test system will be specifically described in combination with the specific structure of the test system in this embodiment.

The structural diagram of the performance evaluation motherboard shown in Figure 3, in this embodiment, a PWM signal access port, a DC-link voltage access port, a drive voltage access port and a sub-board are provided on the performance evaluation motherboard 200 Docking port. Wherein, the PWM signal access port includes two PWM signal sub-ports, one PWM signal sub-port provides the upper switch tube PWM signal for the upper switch tube 320, and the other PWM signal sub-port provides the lower switch tube PWM signal for the lower switch tube 340, The input voltage of the driving voltage access port is 5V, and the daughter board plug port is used to connect the performance evaluation daughter board with the performance evaluation motherboard.

In this embodiment, the testing system further includes an auxiliary low voltage power supply 400 , an adjustable high voltage DC voltage source 500 and a digital signal processing control board 600 . Wherein, the auxiliary low-voltage power supply 400 is connected to the corresponding access port (driving voltage access port) of the performance evaluation motherboard 200, and the auxiliary low-voltage power supply 400 is used to provide the driving voltage, which is also used as the temperature control of the temperature-controlled heating unit 350. voltage, the driving voltage is 5V.

The adjustable high-voltage DC voltage source 500 is connected to the corresponding access port (DC-link voltage access port) of the performance evaluation motherboard 200, and the adjustable high-voltage DC voltage source 500 is used to provide an adjustable DC-link voltage. In the example, the DC-link voltage provides DC-link voltages with different test requirements for the half-bridge circuit composed of the upper switching tube 320 , the lower switching tube 340 and the load unit 360 .

The digital signal processing control board 600 is connected with the corresponding access ports (two PWM signal sub-ports) of the performance evaluation motherboard 200, and the digital signal processing control board 600 is used to provide adjustable upper switching tube PWM signal and lower switching tube PWM signal. Signal. Optionally, the digital signal processing control board 600 adopts a DSP control board modeled as TI TMS320F28379D to provide programmable PWM signals for the circuit under test.

Further, as shown in FIG. 4 , the structural schematic diagram of the performance evaluation sub-board, in this embodiment, the upper switch tube drive unit 310 includes the connected power supply DC/DC circuit 311 of the upper switch tube drive unit and the upper switch tube drive circuit. 312, wherein, the power supply DC/DC circuit 311 of the upper switching tube drive unit provides the working voltage of the upper switching tube driving circuit 312; the upper switching tube driving circuit 312 is connected with the upper switching tube 320, and the upper switching tube driving circuit 312 The PWM signal controls the turn-on and turn-off of the upper switch 320 .

Similar to the upper switching tube driving unit 310, the lower switching tube driving unit 330 includes a connected power supply DC/DC circuit 331 and a lower switching tube driving circuit 332 of the lower switching tube driving unit, wherein the power supply DC/DC of the lower switching tube driving unit The DC circuit 331 provides the operating voltage of the lower switch tube drive circuit 332; the lower switch tube drive circuit 332 is connected to the lower switch tube 340, and the lower switch tube drive circuit 332 controls the opening and closing of the lower switch tube 340 according to the lower switch tube PWM signal.

In this embodiment, the corresponding PWM signal is obtained through programming, and switching instructions of different frequencies, double pulses or continuous pulses are provided for the upper switching tube 320 and the lower switching tube 340, so as to realize the opening and closing of the upper switching tube 320 and the lower switching tube 340. off.

Further, the temperature control voltage of the temperature control heating unit 350 is a driving voltage, and the temperature control heating unit 350 is a heating resistor. By adjusting the resistance value of the heating resistor, different temperature test conditions are provided.

It should be noted that since the heating resistor of the temperature-controlled heating unit is close to the GaN power device under test, in this embodiment, a The through hole is convenient to observe the temperature of the GaN power device under test from the back of the performance evaluation daughter board through the through hole.

Further, the load unit 360 includes a first load subunit 361 and a second load subunit 362 . The circuit connection schematic diagram of double pulse and continuous pulse mode is shown in Fig. 5, the diagram a in Fig. 5 is the circuit connection schematic diagram of double pulse mode, and the diagram b is the circuit connection schematic diagram of continuous pulse mode. Specifically, the first load sub-unit 361 includes a first inductor L1, and the first inductor L1 is connected between the source and the drain of the upper switching transistor 320 . The second load subunit 362 includes a second inductor L2, a first capacitor C1, and a first resistor R1, wherein the first end of the second inductor L2 is connected to the source of the switching transistor 320, and the first capacitor C1 and the first resistor R1 It is connected in series between the second end of the second inductor L2 and the drain of the upper switching transistor 320, that is, the first end of the first capacitor C1 is connected to the drain of the upper switching transistor 320, and the second end is connected to the second inductor L2. The second terminal of the first resistor R1 is connected in parallel with the first capacitor C1.

In this embodiment, the first capacitor C1 is used as a decoupling capacitor to effectively alleviate the oscillation that affects the measurement caused by unavoidable parasitic parameters in the circuit.

In this embodiment, when the first load subunit 361 is connected to the upper switch tube 320, by adjusting the load of the first inductor L1, test conditions for different load currents in double pulse mode are provided; when the second load subunit 362 is connected to the upper The switching tube 320 is connected, and by adjusting the load of the second inductor L2 and the first resistor R1, test conditions of different switching modes and different load currents in the continuous charging mode are provided.

Further, the test circuit module further includes a second capacitor C2 and a voltage clamping circuit, wherein the second capacitor C2 is connected between the upper switch tube 320 and the lower switch tube 340, specifically, the second capacitor C2 is connected across the upper between the drain of the switching transistor 320 and the source of the lower switching transistor 340 . The voltage clamping circuit is connected between the drain and the source of the lower switching transistor 340 .

In this embodiment, the test circuit module further includes a third capacitor C3, and the third capacitor C3 is connected between the second capacitor C2 and the ground terminal GND as a decoupling capacitor of the circuit.

In this embodiment, the performance evaluation sub-board 100 is provided with measurement ports for measuring the gate-source voltage and source-drain voltage of the upper switch tube 320, and for measuring the gate-source voltage, source-drain voltage and drain current of the lower switch tube 340. port, a measurement port for measuring the conduction voltage of the lower switch tube 340, and a current sensor arranged between the source of the lower switch tube 340 and the signal GND, the current sensor is used to measure the lower switch tube 340, that is, the gallium nitride to be tested The on-state current of a power device. Utilize above-mentioned measuring port, by connecting corresponding current sensor, current probe, voltage clamping circuit (the voltage clamping circuit is connected between the source and the drain of lower switching tube 340) and voltage probe, to measure the measured GaN Current and voltage parameters of switching characteristics and conduction characteristics of power devices under dynamic conditions.

Please refer to FIG. 6 . FIG. 6 is a test schematic diagram of a test system for researching characteristics of GaN power devices under dynamic working conditions provided by an embodiment of the present invention. The specific test process of the test system of this embodiment will be described in conjunction with FIG. 6 .

In the test system of this embodiment, by adjusting the current of the heating resistor of the temperature-controlled heating unit 350, the characteristics of the GaN power device under test under different temperatures and dynamic working conditions can be investigated. By adjusting the load subunit connected to the upper switching tube 320, and the load size of the corresponding load subunit, the GaN power device under test can be implemented in different load currents, different pulse modes and different switching modes (soft switching, hard switching, half-switching, etc.) Characteristic measurements under soft switching). Utilize the digital signal processing control board 600 to drive the upper switching tube 320 and the lower switching tube 340 of the performance evaluation sub-board 100 to provide switching instructions for PWM signals with programmable adjustable pulse widths (different frequencies), to investigate the measured nitriding The characteristics of gallium power devices under dynamic conditions and different frequencies.

In this embodiment, optionally, a current sensor, a current probe, a voltage clamping circuit, a voltage probe, an oscilloscope 1 and an oscilloscope 2 are used to respectively realize the switching characteristics and dynamic resistance of the GaN power device under test under dynamic conditions. Continuous measurement and characterization of characteristic current parameters and voltage parameters. For example, the monitoring of dynamic resistance can be obtained by measuring the on-state voltage (V _ds,on ) and on-state current (I _d ) of the GaN power device under test and the division operation of the Tektronix MDO3104 oscilloscope (V _ds ,on ) _on =R _ds,on /I _d ), wherein, the voltage clamping circuit can dynamically monitor the change of V _ds,on of the GaN power device under test under different test conditions, and the measurement of the conduction current can be realized by a current probe.

The test system for researching the characteristics of GaN power devices under dynamic working conditions in this embodiment is based on a comprehensive environmental model for the research of dynamic resistance of GaN power devices. Investigation under different temperature scenarios; the adjustable DC-link voltage can realize different DC-link voltages in the environmental model; the load unit can make the GaN power device under test work in different currents, switching modes, and pulse modes; The adjustable PWM signal provides switching commands for switching tubes with different frequencies; the test system includes comprehensive environmental model variables for the research of dynamic resistance of GaN power devices, and can measure and study the dynamics of GaN power devices under different combinations of working conditions. The purpose of the characteristics under the operating conditions.

It should be noted that due to comprehensive design considerations such as different device structures, heat dissipation, and parasitic optimization, the current GaN power devices adopt different packaging forms. Therefore, according to GaN power devices in different packages, there are The targeted design minimizes the performance evaluation sub-board of loop parasitic parameters, so that the relevant characteristics of GaN power devices in different packages can be accurately measured and characterized under high-frequency and continuous pulses, and the nitrogen in different packages can be realized. Synchronous measurement of switching characteristics and dynamic resistance characteristics of GaN power devices under different combinations of test conditions (including temperature, DC-link voltage, current, frequency, switching mode and pulse mode, etc.).

The temperature, load, PWM signal, and DC-link voltage in the test system for the research on the characteristics of GaN power devices under dynamic working conditions in this embodiment can be independently adjusted, that is, for each power supply working condition of GaN power devices. Environmental factors (temperature, DC-link voltage, current, frequency, switching mode and pulse mode) are flexible and adjustable, and the corresponding environmental factor combinations can be designed according to different research and test purposes, so as to realize the measurement of GaN power devices under test. Targeted research on switching characteristics and dynamic resistance characteristics under different dynamic conditions.

It is worth noting that the test system for researching the characteristics of GaN power devices under dynamic working conditions in this embodiment can be flexibly expanded to other performance research fields other than the electrical characteristics of GaN power devices. The DSP control board in the test system can be triggered by the logic gate level signal (Transistor-Transistor Logic, TTL) of other test systems, and synchronize the test trigger signals of different test systems to expand the synchronous research on nitriding under dynamic conditions. Applications of other characteristic parameters of gallium power devices. For example, under dynamic working conditions, the electrical and thermal characteristics of GaN power devices are affected by the coupling of device structure, device transient electrical characteristics, device transient temperature characteristics, and device channel mechanical stress. The test system can By identifying the synchronous TTL signal of the thermal test equipment to realize the synchronous multi-dimensional investigation of the electrical and thermal characteristics of GaN power devices under dynamic conditions, it can provide (ultra) wide bandgap semiconductor power devices under transient conditions The thermoelectric coupling mechanism research below provides more details and factual basis of thermoelectric characteristics.

It should be noted that in this article, relational terms such as first and second etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is a relationship between these entities or operations. There is no such actual relationship or order between them. Furthermore, the terms "comprises", "comprises" or any other variation are intended to cover a non-exclusive inclusion such that an article or device comprising a set of elements includes not only those elements but also other elements not expressly listed. Without further limitations, an element defined by the phrase "comprising a" does not exclude the presence of additional identical elements in the article or device comprising said element. Words such as "connected" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The orientation or positional relationship indicated by "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying References to devices or elements must have a particular orientation, be constructed, and operate in a particular orientation and therefore should not be construed as limiting the invention.

The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be assumed that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field of the present invention, without departing from the concept of the present invention, some simple deduction or replacement can be made, which should be regarded as belonging to the protection scope of the present invention.

Claims (9)

1. A test system for characteristic research of a gallium nitride power device under dynamic working conditions is characterized by comprising: a performance evaluation daughter board and a performance evaluation mother board, wherein,

the performance evaluation motherboard comprises a plurality of access ports and a plurality of control modules, wherein the access ports are used for receiving input PWM signals, DC-link voltage and driving voltage, and both the PWM signals and the DC-link voltage can be regulated; the performance evaluation daughter board is plugged with the performance evaluation mother board to acquire the PWM signal, the DC-link voltage and the driving voltage;

the performance evaluation daughter board is provided with a test circuit module, the test circuit module comprises an upper switch tube driving unit, an upper switch tube, a lower switch tube driving unit, a lower switch tube, a temperature control heating unit, a load unit and a plurality of measurement ports, wherein,

the lower switching tube is a tested gallium nitride power device; the upper switching tube and the lower switching tube are connected to form a half-bridge circuit; the DC-link voltage provides working voltage required by the half-bridge circuit;

the upper switching tube driving unit is connected with the upper switching tube and controls the upper switching tube to be turned on or turned off according to the PWM signal; the lower switching tube driving unit is connected with the lower switching tube and controls the lower switching tube to be turned on or turned off according to the PWM signal;

the load unit is connected with the upper switch tube; the temperature control heating unit is attached to the lower switch tube;

different test condition combinations are obtained by adjusting the temperature control heating unit, the load unit, the PWM signal and the DC-link voltage, and the electrical characteristic parameter measurement of the tested gallium nitride power device under different test condition combinations is realized by utilizing the plurality of measurement ports.

2. The system for testing the characteristics of the GaN power device under the dynamic working condition according to claim 1, wherein the upper switch tube driving unit comprises a power supply DC/DC circuit and an upper switch tube driving circuit of the upper switch tube driving unit which are connected, wherein,

a power supply DC/DC circuit of the upper switching tube driving unit provides working voltage of the upper switching tube driving circuit;

the upper switch tube driving circuit is connected with the upper switch tube and controls the upper switch tube to be turned on and off according to the PWM signal of the upper switch tube.

3. The system for testing the characteristics of the gallium nitride power device under the dynamic working condition according to claim 2, wherein the lower switch tube driving unit comprises a power supply DC/DC circuit of the lower switch tube driving unit and a lower switch tube driving circuit which are connected, wherein,

a power supply DC/DC circuit of the lower switching tube driving unit provides working voltage of the lower switching tube driving circuit;

the lower switching tube driving circuit is connected with the lower switching tube and controls the lower switching tube to be turned on and off according to a lower switching tube PWM signal.

4. The system for testing the characteristic research of the gallium nitride power device under the dynamic working condition according to claim 1, wherein the temperature control voltage of the temperature control heating unit is the driving voltage, the temperature control heating unit is a heating resistor, and the testing conditions of different temperatures are provided by adjusting the resistance value of the heating resistor.

5. The system for testing the characteristics of the GaN power device under the dynamic condition of claim 1, wherein the load unit comprises a first load subunit and a second load subunit, wherein,

the first load subunit comprises a first inductor, and the first inductor is connected between the source electrode and the drain electrode of the upper switching tube;

the second load subunit comprises a second inductor, a first capacitor and a first resistor, wherein the first end of the second inductor is connected with the source electrode of the upper switching tube, and the first capacitor and the first resistor are connected in series between the second end of the second inductor and the drain electrode of the upper switching tube;

when the first load subunit is connected with the upper switching tube, test conditions of different load currents in a double-pulse mode are provided by adjusting the load of the first inductor;

when the second load subunit is connected with the upper switching tube, test conditions of different switching modes and different load current modes in a continuous flushing mode are provided by adjusting the load of the second inductor and the first resistor.

6. The system for testing the characteristics of the gallium nitride power device under the dynamic working condition according to claim 1, wherein the test circuit module further comprises a second capacitor and a voltage clamp circuit, wherein the second capacitor is connected across the upper switching tube and the lower switching tube, and the voltage clamp circuit is connected between the drain and the source of the lower switching tube.

7. The system for testing the characteristic research of the gallium nitride power device under the dynamic working condition according to claim 1, further comprising an auxiliary low voltage power supply connected to the corresponding access port of the performance evaluation motherboard, wherein the auxiliary low voltage power supply is used for providing the driving voltage.

8. The system of claim 1, further comprising an adjustable high voltage DC voltage source connected to a corresponding access port of the performance evaluation motherboard, the adjustable high voltage DC voltage source configured to provide an adjustable DC-link voltage.

9. The system for testing the characteristics of the gallium nitride power device under dynamic conditions according to claim 3, further comprising a digital signal processing control board connected to the corresponding access ports of the performance evaluation motherboard, the digital signal processing control board being configured to provide the adjustable upper switching tube PWM signal and the adjustable lower switching tube PWM signal.

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