SiC MOSFET driving voltage dynamic adjusting method and related device

Abstract

The invention discloses a SiC MOSFET driving voltage dynamic adjustment method and a related device. The method comprises the following steps: calculating a safe working current value and a load current amplitude maximum value according to device parameters of a current SiC MOSFET device; calculating load current intervals corresponding to different driving voltages according to the safe working current value and a preset driving voltage node value; and if the real-time load current of the current SiC MOSFET device is within the over-current period range, determining a step-down driving voltage value according to the real-time load current and the load current interval, otherwise, keeping the standard driving voltage value. According to the method and the device, the technical problems that the overcurrent suppression effect is poor and unnecessary loss is increased due to the fact that a static adjustment method depending on a fixed value does not consider the actual working condition of the device and lacks pertinence in the prior art can be solved.

Description

Technical Field

[0001] The present application relates to the field of circuit control technology, and in particular to a SiC MOSFET driving voltage dynamic regulation method and related devices. Background Art

[0002] The third generation wide bandgap semiconductor devices represented by SiC MOSFET are gradually becoming the preferred choice for future high-power converters because of their lower on-resistance, smaller switching loss, higher switching speed, and better suitability for high-voltage, high-temperature, and high-frequency working environments. However, higher voltage and switching speed as well as parasitic parameters in the SiC MOSFET power circuit will cause a larger di / dt, causing the device to have current overshoot problems during the switching process, reducing the output capacity, electromagnetic compatibility, and operational reliability of SiC-based converters. This problem has become one of the obstacles restricting the widespread application of SiC MOSFET.

[0003] In order to solve the current overshoot problem caused by the high switching speed of SiC MOSFET, the traditional driving scheme is to reduce the driving voltage to a fixed value at certain stages of the SiC MOSFET turn-on process to achieve the current overshoot suppression of SiC MOSFET. However, this control scheme does not take into account the actual working conditions, lacks pertinence, has limited overshoot suppression effect and easily causes unnecessary loss increase. Therefore, this method is difficult to achieve effective balance between current overshoot suppression and efficiency optimization under different load currents. Summary of the invention

[0004] The present application provides a SiC MOSFET driving voltage dynamic regulation method and related devices, which are used to solve the technical problems that the static regulation method of the prior art relies on a fixed value and does not take into account the actual working conditions of the device, lacks specificity, leads to poor overcurrent suppression effect, and increases unnecessary losses.

[0005] In view of this, the first aspect of the present application provides a method for dynamically adjusting a SiC MOSFET driving voltage, comprising:

[0006] Calculate the safe operating current value and the maximum load current amplitude based on the device parameters of the current SiC MOSFET device;

[0007] Calculating load current intervals corresponding to different driving voltages according to the safe working current value and the preset driving voltage node value;

[0008] If the real-time load current of the current SiC MOSFET device is within the overcurrent period range, the buck driving voltage value is determined according to the real-time load current and the load current interval; otherwise, the standard driving voltage value is retained.

[0009] Preferably, the calculation process of the safe working current value is:

[0010]

[0011] in, is the drain-source voltage, The shell temperature is The power consumption is , They represent the maximum allowable junction temperature and the maximum allowable case temperature of the SiC MOSFET device during the switching process, The pulse is The transient impedance from junction to case.

[0012] Preferably, the calculation of the load current intervals corresponding to different driving voltages according to the safe working current value and the preset driving voltage node value includes:

[0013] Calculate multiple interval load current maximum values ​​according to the safe working current value and the preset driving voltage node value;

[0014] Based on the maximum load current value in the interval and the maximum load current amplitude value, load current intervals corresponding to different driving voltages are generated.

[0015] Preferably, if the real-time load current of the current SiC MOSFET device is within the overcurrent period range, the step-down driving voltage value is determined according to the real-time load current and the load current interval, otherwise the standard driving voltage value is retained, and the above also includes:

[0016] The turn-on transient characteristic analysis of the current SiC MOSFET device is performed through the turn-on period division operation to determine a plurality of turn-on drive periods, wherein the turn-on drive period includes an overcurrent period.

[0017] A second aspect of the present application provides a SiC MOSFET driving voltage dynamic adjustment device, comprising:

[0018] A parameter calculation unit, used for calculating a safe operating current value and a maximum load current amplitude value according to device parameters of a current SiC MOSFET device;

[0019] An interval analysis unit, used for calculating the load current intervals corresponding to different driving voltages according to the safe working current value and the preset driving voltage node value;

[0020] The drive adjustment unit is used to determine the step-down drive voltage value according to the real-time load current and the load current interval if the real-time load current of the current SiC MOSFET device is within the overcurrent period range, and otherwise retain the standard drive voltage value.

[0021] Preferably, the calculation process of the safe working current value is:

[0022]

[0023] in, is the drain-source voltage, The shell temperature is The power consumption is , They represent the maximum allowable junction temperature and the maximum allowable case temperature of the SiC MOSFET device during the switching process, The pulse is The transient impedance from junction to case.

[0024] Preferably, the interval analysis unit is specifically used for:

[0025] Calculate multiple interval load current maximum values ​​according to the safe working current value and the preset driving voltage node value;

[0026] Based on the maximum load current value in the interval and the maximum load current amplitude value, load current intervals corresponding to different driving voltages are generated.

[0027] Preferably, it also includes:

[0028] The time period analysis unit is used to perform a turn-on transient characteristic analysis on the current SiC MOSFET device through a turn-on period division operation to determine a plurality of turn-on drive time periods, wherein the turn-on drive time period includes an overcurrent time period.

[0029] A third aspect of the present application provides a SiC MOSFET driving voltage dynamic adjustment device, the device comprising a processor and a memory;

[0030] The memory is used to store program code and transmit the program code to the processor;

[0031] The processor is used to execute the SiC MOSFET driving voltage dynamic adjustment method described in the first aspect according to the instructions in the program code.

[0032] A fourth aspect of the present application is a computer-readable storage medium, wherein the computer-readable storage medium is used to store program code, and the program code is used to execute the SiC MOSFET driving voltage dynamic adjustment method described in the first aspect.

[0033] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0034] In the present application, a method for dynamically adjusting a SiC MOSFET driving voltage is provided, comprising: calculating a safe operating current value and a maximum load current amplitude according to device parameters of a current SiC MOSFET device; calculating a load current interval corresponding to different driving voltages according to the safe operating current value and a preset driving voltage node value; if the real-time load current of the current SiC MOSFET device is within an overcurrent period, determining a step-down driving voltage value according to the real-time load current and the load current interval, otherwise retaining a standard driving voltage value.

[0035] The SiC MOSFET driving voltage dynamic adjustment method provided by the present application takes into account the current constraint under the safe working state of the device, the overcurrent period range analysis, and the interval analysis of the load current that affects the driving voltage. It can analyze the driving voltage of different sections based on the actual working conditions to the greatest extent, set different load current intervals to select different driving voltage values ​​to achieve dynamic adjustment of the driving voltage, and ensure that it is more accurate and reliable than the static adjustment of fixed values, and improve the overcurrent suppression effect to a certain extent. Therefore, the present application can solve the technical problems that the static adjustment method of the prior art that relies on fixed values ​​does not take into account the actual working conditions of the device, lacks pertinence, leads to poor overcurrent suppression effect, and increases unnecessary losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic diagram of a flow chart of a method for dynamically adjusting a SiC MOSFET driving voltage provided in an embodiment of the present application;

[0037] Figure 2 A schematic diagram of the structure of a SiC MOSFET driving voltage dynamic regulation device provided in an embodiment of the present application;

[0038] Figure 3 A schematic diagram of the double pulse test circuit structure considering stray parameters provided in an embodiment of the present application;

[0039] Figure 4 A simplified waveform diagram of the SiC MOSFET turn-on process provided in an embodiment of the present application;

[0040] Figure 5 A schematic diagram of the simulation circuit structure provided for the simulation application example of this application;

[0041] Figure 6 A waveform diagram of a load current of 40A during the SiC MOSFET turn-on process provided for the simulation application example of this application;

[0042] Figure 7The voltage and current waveforms obtained by driving control based on the driving voltage when the load current is in the overcurrent suppression interval provided in the simulation application example of this application are the traditional strategy and the strategy of this application Figure 1 ;

[0043] Figure 8 The voltage and current waveforms obtained by driving control based on the driving voltage when the load current is in the overcurrent suppression interval provided in the simulation application example of this application are the traditional strategy and the strategy of this application Figure 2 ;

[0044] Fig. 9 The voltage and current waveforms obtained by driving control based on the driving voltage when the load current is in the overcurrent suppression interval provided in the simulation application example of this application are the traditional strategy and the strategy of this application Figure 3 ;

[0045] Fig.10 A rectangular diagram comparing the losses of driving voltage regulation in sequence between the traditional strategy and the strategy of the present application provided in the simulation application example of the present application. DETAILED DESCRIPTION

[0046] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0047] For easier understanding, see Figure 1 , an embodiment of a SiC MOSFET driving voltage dynamic adjustment method provided by the present application includes:

[0048] It should be noted that, before analyzing the dynamic regulation of the driving voltage of the SiC MOSFET device, this embodiment needs to analyze the transient characteristics of the SiC MOSFET device to obtain some rules and formulas to facilitate subsequent calculation and derivation. Figure 3 , where L g1 , L d , L S They are the gate parasitic inductance, drain parasitic inductance, and source parasitic inductance of SiC MOSFET respectively; CF is the junction capacitance of the freewheeling diode; R g_in , R g_ex They are the internal gate resistance and external drive resistance of SiC MOSFET respectively; L g2 , L p , L load They are the parasitic inductance of the gate loop (except L g1The parasitic inductance of the external drive circuit), the parasitic inductance of the power circuit (the parasitic inductance of the power circuit outside the power module), and the load inductance.

[0049] Since the current overshoot problem generally occurs during the device's turn-on process, this embodiment mainly analyzes the turn-on transient characteristics of the SiC MOSFET device and does not discuss the turn-off process. Figure 4 , the process can be divided into four stages; among them, V gg With V gs are the driving voltage and the SiC MOSFET gate-source voltage, V cc With V ee are the driving voltage amplitudes applied during the turn-on and turn-off processes, V th is the threshold voltage for SiC MOSFET to turn on, I d is the drain current, V ds is the drain-source voltage, I L is the load current amplitude, V DC is the DC bus voltage.

[0050] Phase 1 ):exist At this moment, the driving voltage is negative voltage V ee Becomes positive pressure V cc And through the drive circuit to the input capacitor C iss Charging, where C iss =C gs +C gd . V gs Starts to rise, V gs The relationship with time t can be expressed as:

[0051]

[0052] in, When V gs Increases to the threshold voltage V th When the SiC MOSFET starts to conduct, I d Then it rises, and stage 1 ends. This stage is the delay time required for the SiC MOSFET device to turn on from off. It can be expressed as:

[0053]

[0054] According to the above formula, the driving voltage amplitude V cc The larger the delay time, The shorter the SiC MOSFET is, the faster the turn-on speed of the SiC MOSFET device will be.

[0055] Phase 2 ): At this moment, the load current starts to transfer from the freewheeling diode branch to the SiC MOSFET, I d Then it rises, V ds After a small landing, we entered Miller Platform. L After all transfer to SiC MOSFET, due to the reverse recovery characteristics of the freewheeling diode, I d It will continue to increase to the peak value I d_max , in this process I d with I d_max Can be expressed as:

[0056]

[0057]

[0058] in, is a constant, is the reverse recovery charge of the freewheeling diode, I d The rise time directly determines the rate of change of current, so based on I d The formula can be deduced:

[0059]

[0060] According to the above formula, V gs and its rate of change determine I d The rising rate of V gs Same as the state in stage 1, it still grows according to the exponential law, so, combined with the first formula above, we can see that V gs The growth rate can be expressed as:

[0061]

[0062] Combining the above three formulas, we can get:

[0063]

[0064] Based on this formula, I d_max and the driving voltage amplitude V cc There is a positive correlation, and according to this formula, the maximum drain current I can be obtained d_max .

[0065] In this stage, I d Continue to rise to the peak value, the traditional 20V drive voltage I d_maxIt is easy to exceed the safe operating current of the device, which will have a huge impact on the SiC MOSFET and cause device damage. Therefore, the driving voltage amplitude V is reasonably reduced in this stage. cc It is beneficial to suppress the current overshoot phenomenon during the turn-on process.

[0066] Phase 3 ):V ds Start to descend, I d After reaching the peak, it fluctuates several times and finally stabilizes at I L Up, V gs Stop rising and keep the Miller voltage constant. d There is a more obvious oscillation phenomenon, continuing the low drive voltage amplitude V cc It is helpful to suppress current oscillation.

[0067] Phase 4 ( ): The driving power supply continues to be the gate-source capacitance Gate-drain capacitance Charge until V gs Rising to the positive drive voltage V cc In this stage, the driving voltage amplitude V is increased. cc The saturation conduction time can be shortened, the conduction process of SiC MOSFET can be accelerated, and the on-resistance can be reduced to improve the efficiency of the converter device.

[0068] Based on the above analysis, it can be seen that the driving circuit uses a relatively high driving voltage of 20V to complete the opening of the SiC MOSFET, which is prone to cause current overshoot problems in stage 2 and stage 3, and the current overshoot value is related to the driving voltage and the load current. Reducing the driving voltage can achieve the effect of suppressing current overshoot, but it will slow down the opening speed of the device and cause an increase in loss. Therefore, this embodiment reasonably adjusts the driving voltage according to the load current size, and then balances the relationship between low current overshoot and low loss.

[0069] Step 101: Calculate a safe operating current value and a maximum load current amplitude according to device parameters of a current SiC MOSFET device.

[0070] Furthermore, the calculation process of the safe working current value is:

[0071]

[0072] in, is the drain-source voltage, The shell temperature is The power consumption is , They represent the maximum allowable junction temperature and the maximum allowable case temperature of the SiC MOSFET device during the switching process, The pulse is The transient impedance from junction to case is d_max To safe working current value I SOA As a principle, it is possible to consider using low drive voltages with different amplitudes in different load current ranges. To suppress current overshoot while ensuring control efficiency.

[0073] Assume that the rated current of the selected SiC MOSFET device is , calculate the upper limit of the load current value in actual situation under the premise of considering 1.5~2 times margin , which can be expressed as ,in, In order to consider the common sense of 1.5~2 times margin, the value is taken as 1.5~2; after calculation, the maximum load current amplitude can be obtained.

[0074] Step 102: Calculate load current intervals corresponding to different driving voltages according to the safe operating current value and the preset driving voltage node value.

[0075] Furthermore, step 102 includes:

[0076] Calculate multiple interval load current maximum values ​​according to the safe working current value and the preset driving voltage node value;

[0077] Based on the maximum load current value in the interval and the maximum load current amplitude value, load current intervals corresponding to different driving voltages are generated.

[0078] If the adjustable driving voltage value is set, the preset driving voltage node values ​​are 20V, , , Then we can calculate that the driving voltage at a specific stage is 20V, , The corresponding load current values ​​in multiple intervals are recorded as , , The specific load current calculation process is expressed as:

[0079]

[0080] So the low amplitude driving voltage A corresponding relationship can be established between the value of and the load current, that is, different driving voltages correspond to different load current intervals, and the driving voltages corresponding to these current intervals can make the maximum value of the drain current not exceed the safe working current value, that is . Please refer to Table 1 for details.

[0081] Table 1 Correspondence between driving voltage and load current range

[0082]

[0083] Based on Table 1, we can see that , , are the maximum values ​​of their respective intervals, that is, the maximum load current of the interval; and, even if the drive voltage is When the load current is , cannot cover all load currents. If the current is not too high, the driving voltage should be further reduced to .

[0084] Step 103: If the current real-time load current of the SiC MOSFET device is within the overcurrent period, the buck driving voltage value is determined according to the real-time load current and the load current interval; otherwise, the standard driving voltage value is retained.

[0085] Furthermore, step 103, before that, also includes:

[0086] The turn-on transient characteristic analysis of the current SiC MOSFET device is performed through the turn-on period division operation, and a plurality of turn-on drive periods are determined, wherein the turn-on drive period includes an overcurrent period.

[0087] The analysis of the turn-on transient characteristics of SiC MOSFET devices has been described above. Through the analysis of multiple determined turn-on drive periods, it can be seen that the overcurrent period of the SiC MOSFET turn-on process is combined with the real-time load current and the load current interval, that is, The driving voltage is dynamically adjusted in the stage. Specifically, when the real-time load current falls within a specific load current range and the turn-on process belongs to the overcurrent period When using a low drive voltage value , that is, the driving voltage value is stepped down for driving control; this can not only reduce the current overshoot value to below the safe working current, but also avoid unnecessary loss increase; while the 20V standard driving voltage is kept unchanged in the remaining stages. The selection of driving voltage is mainly based on the current range of the real-time load current and the opening driving period of the current opening process.

[0088] The specific analysis of the opening driving period is as follows: 1) : PWM signal is high level, driving voltage 20V, speeding up the charging process to shorten the turn-on delay time, the gate-source voltage Start to rise.

[0089] 2) : The PWM signal is high level, and the drive voltage is reduced to the set value , drain current The rate of change decreases accordingly, The peak value is further reduced.

[0090] 3) :The driving voltage is maintained at , the amplitude of current oscillation decreases and the oscillation process is shortened.

[0091] 4) :The driving voltage is restored to 20V, accelerating the drain-source voltage This reduces the on-resistance and improves efficiency.

[0092] The load current range to which the real-time load current is assigned can be determined based on the real-time sampling, and the appropriate and corresponding drive voltage can be selected for drive control in combination with the time period of the on-drive. The drive voltage is dynamically adjusted in the phase. For example, if the real-time load current The interval is , then the normal driving voltage of 20V is used regardless of the time period; if The interval is , then in The driving voltage is used for the period , the other stages still use 20V.

[0093] For ease of understanding, this application provides a simulation application example of a SiC MOSFET driving voltage dynamic adjustment method. Figure 5 The research object is SiC MOSFET (C3M0016120K, 1200V / 115A). This application uses LTspice simulation software based on a double pulse test platform to verify the effectiveness of the proposed method. The test circuit diagram is shown in Figure 5 As shown in the figure, the lower tube is used as the test object, and the upper tube is in the negative pressure off state and used as a freewheeling diode. Please refer to Table 2 for simulation parameters.

[0094] Table 2 Simulation circuit parameters

[0095]

[0096] Combined with the selected SiC MOSFET model, it can be calculated 125A, is 90A; the load current range is divided according to the driving voltage of different amplitudes, and the results are shown in Table 3.

[0097] Table 3 Relationship between load current and driving voltage

[0098]

[0099] Take a point in each load current range to get the voltage and current waveforms when the load current is 40A, 60A, 68A and 80A. For an example of the waveform at 40A, see Figure 6 When the load current is 40A, the device is turned on with a 20V drive voltage and the current overshoot value does not exceed (125A), so in order to speed up the turn-on process and reduce losses, the 20V drive voltage is kept unchanged throughout the turn-on process.

[0100] When the load current takes the current value of the overcurrent suppression interval, the voltage and current waveforms of the conventional strategy maintaining a 20V driving voltage during the turn-on process and the strategy proposed in this application are compared to verify whether the proposed strategy can effectively suppress current overshoot. The obtained waveform is as follows: Figure 7 , 8 As shown in , the waveforms on the left side of the figure are the waveforms of the traditional strategy, and the waveforms on the right side are the waveforms of the strategy proposed in this application. Figure 7 , 8 9, when the load current is 60A, 68A, and 80A, if the driving voltage is kept constant at 20V during the opening process, I d_max The values ​​will reach 129A, 138A and 151A respectively, all exceeding I SOA (125A), so it is necessary to dynamically adjust the drive voltage according to the load current feedback. Based on Table 3, the drive voltage is reduced to 17V, 15V, and 12V at specific stages of the turn-on process, and remains at 20V in the remaining stages. It can be seen from the adjusted current waveform that each I d_max The corresponding values ​​are reduced to 121A, 122A, and 118A, all reduced to below 125A. This shows that the strategy provided in the present application can effectively suppress current overshoot and thus ensure the reliability of SiC MOSFET.

[0101] Combined with the comparison of the advantages and disadvantages of the traditional driving strategy and the strategy proposed in this application, the current peak and loss of the two strategies can be found in Fig.10, when the load current is 60A, 68A, and 80A, the driving voltage needs to be reduced to 17V, 15V, and 12V respectively at specific stages of the SiC MOSFET turn-on process. Compared with the traditional strategy, after adopting the strategy proposed in this application, the current peaks under different load currents decreased by 8A (13.3%), 16A (23.53%), and 33A (41.25%), respectively, and the corresponding losses increased by 1.11%, 1.15%, and 6.98%, respectively. It can be seen that the current overshoot values ​​after the driving voltage adjustment are all reduced to below 125A, and the losses have not increased significantly. Therefore, by adjusting the driving voltage at a specific stage, the device current overshoot can be suppressed without causing a significant increase in losses, thereby effectively improving the reliability of the SiC MOSFET.

[0102] The SiC MOSFET driving voltage dynamic adjustment method provided by the present application embodiment takes into account the current constraint under the safe working state of the device, the overcurrent period range analysis, and the interval analysis of the load current that affects the driving voltage. It can analyze the driving voltage of different sections based on the actual working conditions to the greatest extent, set different load current intervals to select different driving voltage values ​​to achieve dynamic adjustment of the driving voltage, and ensure that it is more accurate and reliable than the static adjustment of fixed values, and improve the overcurrent suppression effect to a certain extent. Therefore, the embodiment of the present application can solve the technical problems that the static adjustment method of the prior art that relies on fixed values ​​does not take into account the actual working conditions of the device, lacks pertinence, leads to poor overcurrent suppression effect, and increases unnecessary losses.

[0103] For easier understanding, see Figure 2 The present application provides an embodiment of a SiC MOSFET driving voltage dynamic adjustment device, comprising:

[0104] A parameter calculation unit 201 is used to calculate a safe operating current value and a maximum load current amplitude value according to device parameters of a current SiC MOSFET device;

[0105] An interval analysis unit 202, used to calculate load current intervals corresponding to different driving voltages according to the safe working current value and the preset driving voltage node value;

[0106] The drive adjustment unit 203 is used to determine the step-down drive voltage value according to the real-time load current and the load current interval if the real-time load current of the current SiC MOSFET device is within the overcurrent period range, and otherwise retain the standard drive voltage value.

[0107] Furthermore, the calculation process of the safe working current value is:

[0108]

[0109] in, is the drain-source voltage, The shell temperature is The power consumption is , They represent the maximum allowable junction temperature and the maximum allowable case temperature of the SiC MOSFET device during the switching process, The pulse is The transient impedance from junction to case.

[0110] Further, the interval analysis unit 202 is specifically used for:

[0111] Calculate the maximum load current values ​​of multiple intervals according to the safe working current value and the preset driving voltage node value;

[0112] Based on the maximum load current value and the maximum load current amplitude value of the interval, load current intervals corresponding to different driving voltages are generated.

[0113] Furthermore, it also includes:

[0114] The time period analysis unit 204 is used to perform a turn-on transient characteristic analysis on the current SiC MOSFET device through a turn-on period division operation, and determine a plurality of turn-on drive periods, wherein the turn-on drive period includes an overcurrent period.

[0115] The present application also provides a SiC MOSFET driving voltage dynamic regulation device, the device comprising a processor and a memory;

[0116] The memory is used to store the program code and transmit the program code to the processor;

[0117] The processor is used to execute the SiC MOSFET driving voltage dynamic adjustment method in the above method embodiment according to the instructions in the program code.

[0118] The present application also provides a computer-readable storage medium, which is used to store program code, and the program code is used to execute the SiC MOSFET driving voltage dynamic adjustment method in the above method embodiment.

[0119] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0120] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0121] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0122] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a number of instructions for executing all or part of the steps of the method described in each embodiment of the present application through a computer device (which can be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (full name in English: Read-Only Memory, English abbreviation: ROM), random access memory (full name in English: Random Access Memory, English abbreviation: RAM), disk or optical disk and other media that can store program codes.

[0123] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for dynamically adjusting a SiC MOSFET driving voltage, characterized in that: include: Calculate the safe operating current value and the maximum load current amplitude based on the device parameters of the current SiC MOSFET device; Calculating load current intervals corresponding to different driving voltages according to the safe working current value and the preset driving voltage node value; If the real-time load current of the current SiC MOSFET device is within the overcurrent period range, the buck driving voltage value is determined according to the real-time load current and the load current interval; otherwise, the standard driving voltage value is retained.

2. The SiC MOSFET driving voltage dynamic adjustment method according to claim 1, characterized in that: The calculation process of the safe working current value is: in, is the drain-source voltage, The shell temperature is The power consumption is , They represent the maximum allowable junction temperature and the maximum allowable case temperature of the SiC MOSFET device during the switching process, The pulse is The transient impedance from junction to case.

3. The SiC MOSFET driving voltage dynamic adjustment method according to claim 1, characterized in that: The calculating the load current intervals corresponding to different driving voltages according to the safe working current value and the preset driving voltage node value includes: Calculate multiple interval load current maximum values ​​according to the safe working current value and the preset driving voltage node value; Based on the maximum load current value in the interval and the maximum load current amplitude value, load current intervals corresponding to different driving voltages are generated.

4. The SiC MOSFET driving voltage dynamic adjustment method according to claim 1, characterized in that: If the real-time load current of the current SiC MOSFET device is within the overcurrent period range, the step-down driving voltage value is determined according to the real-time load current and the load current interval; otherwise, the standard driving voltage value is retained, and the above also includes: The turn-on transient characteristic analysis of the current SiC MOSFET device is performed through the turn-on period division operation to determine a plurality of turn-on drive periods, wherein the turn-on drive period includes an overcurrent period.

5. A SiC MOSFET driving voltage dynamic adjustment device, characterized in that: include: A parameter calculation unit, used for calculating a safe operating current value and a maximum load current amplitude value according to device parameters of a current SiC MOSFET device; An interval analysis unit, used for calculating the load current intervals corresponding to different driving voltages according to the safe working current value and the preset driving voltage node value; The drive adjustment unit is used to determine the step-down drive voltage value according to the real-time load current and the load current interval if the real-time load current of the current SiC MOSFET device is within the overcurrent period range, and otherwise retain the standard drive voltage value.

6. The SiC MOSFET driving voltage dynamic adjustment device according to claim 5, characterized in that: The calculation process of the safe working current value is: in, is the drain-source voltage, The shell temperature is The power consumption is , They represent the maximum allowable junction temperature and the maximum allowable case temperature of the SiC MOSFET device during the switching process, The pulse is The transient impedance from junction to case.

7. The SiC MOSFET driving voltage dynamic adjustment device according to claim 5, characterized in that: The interval analysis unit is specifically used for: Calculate multiple interval load current maximum values ​​according to the safe working current value and the preset driving voltage node value; Based on the maximum load current value in the interval and the maximum load current amplitude value, load current intervals corresponding to different driving voltages are generated.

8. The SiC MOSFET driving voltage dynamic adjustment device according to claim 5, characterized in that: Also includes: The time period analysis unit is used to perform a turn-on transient characteristic analysis on the current SiC MOSFET device through a turn-on period division operation to determine a plurality of turn-on drive time periods, wherein the turn-on drive time period includes an overcurrent time period.

9. A SiC MOSFET driving voltage dynamic regulation device, characterized in that: The device comprises a processor and a memory; The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the SiCMOSFET driving voltage dynamic regulation method according to any one of claims 1 to 4 according to the instructions in the program code.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store program code, and the program code is used to execute the SiC MOSFET driving voltage dynamic adjustment method according to any one of claims 1 to 4.

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