CN116599512B - Hybrid switch structure of SiC MOSFET, si IGBT and Si MOSFET - Google Patents
Hybrid switch structure of SiC MOSFET, si IGBT and Si MOSFET Download PDFInfo
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- CN116599512B CN116599512B CN202310848095.1A CN202310848095A CN116599512B CN 116599512 B CN116599512 B CN 116599512B CN 202310848095 A CN202310848095 A CN 202310848095A CN 116599512 B CN116599512 B CN 116599512B
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
- H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
- H03K17/567—Circuits characterised by the use of more than one type of semiconductor device, e.g. BIMOS, composite devices such as IGBT
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
- H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
- H03K17/687—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being field-effect transistors
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
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Abstract
The application provides a hybrid switch structure of SiC MOSFET, si IGBT and Si MOSFET, which consists of two parallel branches, wherein a first current branch is the SiC MOSFET, and a second current branch is the series structure of the Si IGBT and the low-voltage Si MOSFET. Compared with the existing SiC MOSFET hybrid Si IGBT switch structure, the hybrid switch structure has the advantages that a low-voltage Si MOSFET is added, the device cost is not increased basically, most of current in the hybrid switch structure flows through the IGBT, the reliability is higher, and meanwhile the problem that the IGBT turns off trailing current is solved.
Description
Technical Field
The application relates to the technical field of semiconductor devices, in particular to a hybrid switch structure of a SiC MOSFET, a Si IGBT and a Si MOSFET.
Background
In recent years, with the high-speed development of the fields of smart grids, new energy automobiles, all-electric airplanes and the like, requirements of high frequency, low loss, high efficiency, high power density and the like are put forward on power electronic devices. The Si IGBT obviously cannot meet the requirements of modern power electronic devices due to the limitations of the self material characteristics and the power electronic device structure and the limit value of the switching frequency of the Si IGBT below 20 kHz. The third-generation semiconductor power device represented by the SiC MOSFET has the advantages of high switching speed, high reverse voltage resistance, small switching loss, high chip heat conductivity and the like, but the manufacturing cost of the SiC MOSFET is still high at present under the limit of the manufacturing process, and the power grade of the SiC MOSFET is obviously smaller than that of the IGBT, so that the SiC MOSFET can only be applied to partial small-power occasions. The Si IGBT and the SiC MOSFET are connected in parallel to form the SiC/Si hybrid device, so that the advantages of high frequency, high voltage resistance and the like of the SiC MOSFET and the advantages of low conduction loss, high power level, low cost and the like of the Si IGBT can be fully exerted. Some studies have shown that SiC MOSFET hybrid SiIGBT devices can achieve higher efficiency and power density while also reducing system cost and volume. Therefore, siC MOSFET hybrid Si IGBTs are expected to become the dominant technology in the future power electronics field.
The existing switch structure mainly uses a single type of device, si MOSFETs are mainly used in the field of some small-power consumer-level power electronic devices, and Si IGBTs are mainly used in the industrial production and manufacture of large and medium power. In the field of the existing relatively hot new energy automobiles, because the application scene of the SiC MOSFET needs to withstand the challenges of high temperature, strong electromagnetic radiation and high frequency, the SiC MOSFET is generally used, and in order to reduce the cost of the SiC MOSFET device and improve the firmness of the whole switch structure, the hybrid switch structure of the SiC MOSFET and the Si IGBT has been proposed.
The prior art has the following defects:
(1) In a pure IGBT structure, the switching loss of the device is larger, and a trailing current phenomenon exists, so that the switching frequency is lower. In the pure Si MOSFET structure, the maximum withstand voltage of a single device is not more than 800V, and the structure cannot be applied to high-voltage occasions. The cost of the pure SiC MOSFET structure and the device is too high;
(2) The SiC MOSFET mixed Si IGBT structure does not solve the problem of the tail current of the IGBT basically, the limit working frequency of the switch is limited by the structure, and instant current spikes can be induced on the Si IGBT at the instant of closing the SiC MOSFET.
Disclosure of Invention
In order to solve the technical problem, the application provides a hybrid switch structure of a SiC MOSFET, a Si IGBT and a Si MOSFET, wherein the switch structure is composed of two parallel branches, a first current branch is the SiC MOSFET, and a second current branch is a series structure of the Si IGBT and a low-voltage Si MOSFET. The switch structure has the advantages of high switching speed, low cost, low switching loss and conduction loss and the like. The technical scheme adopted by the invention is as follows:
a hybrid switch structure of a SiC MOSFET, a Si IGBT and a Si MOSFET comprises two parallel current branches, wherein the first current branch is formed by connecting a field effect tube Q1 and a diode D1 in parallel, and the second current branch is formed by connecting a field effect tube Q2 and a diode D2 in parallel, connecting a field effect tube Q3 and a diode D3 in parallel and then connecting the two current branches in series.
Further, in the hybrid switch structure, Q1 is a SiC MOSFET of 1200V or 1700V, Q2 is a Si IGBT of the same voltage level as the SiC MOSFET, and Q3 is a low voltage Si MOSFET of the same current level as Q2.
Further, the rated current of Q1 is 1/3 to 1/2 of Q2.
Further, D1, D2, and D3 are fast recovery diodes that match the Q1, Q2, and Q3 voltage and current levels.
Further, in the t0-t1 stage, Q1, Q2 and Q3 will simultaneously receive the start signal of the driving circuit at the time t0, the two current branches share the load current, and after Q1, Q2 and Q3 are completely turned on, the current ratio of the first current branch and the second current branch is 1:2 to 1:3.
Further, in the period of t1-t2, Q3 starts to turn off at time t1, and the second current branch starts to transfer to the first current branch, and since Q1 is always in an on state at this time, Q2 is turned off at zero voltage.
Further, in the period t2-t3, Q2 starts to be turned off at the time t2, since Q3 of the second current branch has been turned off before, and Q1 is still in the on state, Q3 is turned off at zero voltage and zero current.
Further, in the period of t3-t4, Q3 starts to turn off at the time t3, and after Q3 turns off, the whole hybrid switch structure is completely turned off.
Further, the sending sequence of the three device turn-off signals is Q3, Q2 and Q1.
Further, the time interval between the off signals is 0.2us to 0.3us.
Through the embodiment of the application, the following technical effects can be obtained:
(1) Compared with the existing pure IGBT switch structure, the switch loss of the hybrid switch structure is greatly reduced, and the switch frequency is higher. Compared with the existing pure Si MOSFET switch structure, the proposed hybrid switch structure has higher rated working voltage and wider application occasions;
(2) Compared with the existing pure SiC MOSFET switch structure, the device cost of the hybrid switch structure is greatly reduced, and most of current in the hybrid switch structure flows through the IGBT, so that the reliability of the hybrid switch structure is higher. Compared with the existing SiC MOSFET hybrid Si IGBT switch structure, the hybrid switch structure has the advantages that a low-voltage Si MOSFET is added, the device cost is not increased basically, and the problem of tail current of IGBT turn-off is solved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments or the description of the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a hybrid switch;
FIG. 2 is a schematic diagram of current distribution for a Si/SiC hybrid switch structure;
fig. 3 is a voltage and current waveform diagram of the SiC MOSFET and Si IGBT hybrid switch structure during turn-off;
FIG. 4 is a voltage and current waveform diagram of a SiC MOSFET, a Si IGBT and a Si MOSFET hybrid switch structure in the turn-off process;
fig. 5 is a schematic diagram of a device switching sequence in a hybrid switching architecture.
Detailed Description
For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.
Fig. 1 is a schematic diagram of a hybrid switch structure. In the hybrid switch structure, Q1 is a 1200V or 1700V SiC MOSFET, Q2 is a Si IGBT with the same voltage level as the SiC MOSFET, and Q3 is a low-voltage Si MOSFET with the same current level as Q2; wherein the rated current of Q1 is 1/3 to 1/2 of Q2;
d1, D2 and D3 are fast recovery diodes that match the Q1, Q2 and Q3 voltage and current levels;
the hybrid switch structure comprises two parallel current branches, wherein the first current branch is formed by connecting Q1 and D1 in parallel, and the second current branch is formed by connecting Q2 and D2 in parallel, connecting Q3 and D3 in parallel and then connecting the two current branches in series.
Fig. 2 is a schematic diagram of current distribution of a Si/SiC hybrid switch structure. It can be seen that when the load current is large, most of the current flows through the IGBT due to the conductance modulation effect, and at the same power level, the turn-on loss of the IGBT is smaller than that of the SiC MOSFET, so that the turn-on loss of the whole hybrid switch structure is smaller than that of the SiC MOSFET.
Compared with the mixed structure of the SiC MOSFET and the Si IGBT, the mixed structure of the SiC MOSFET, the Si MOSFET and the Si IGBT eliminates the trailing current effect of the IGBT, can improve the working frequency of the whole switch structure and reduces the turn-off loss. The reason is that the tail current of the IGBT is derived from the recombination of the minority carrier in the turn-off process, and the Si MOSFET and the Si IGBT are connected in series to form a branch, the MOSFET is turned off before the IGBT, and the recombination channel of the minority carrier of the IGBT is turned off, so that the tail current disappears, and the voltage-current waveform pair is shown in figures 3 and 4.
Fig. 5 is a schematic diagram of a device switching sequence in a hybrid switching architecture. The specific sequence is as follows:
(1) Stage t0-t 1: at time t0, Q1, Q2 and Q3 will receive the start signal of the drive circuit at the same time, the two current branches bear the load current together, after Q1, Q2 and Q3 are fully conducted, the current ratio of the first current branch and the second current branch is 1:2 to 1:3;
(2) Stage t1-t 2: at time t1, Q3 starts to be turned off, the second current branch starts to transfer to the first current branch, and Q2 is turned off at zero voltage because Q1 is always in an on state at the moment;
(3) Stage t2-t 3: at time t2, Q2 starts to turn off, and Q3 is zero voltage and zero current is turned off because Q3 of the previous second current branch has been turned off and Q1 is still in the on state;
(4) Stage t3-t 4: at time t3, Q3 starts to turn off, and at the same power level, Q3 is a SiC MOSFET with a switching loss much smaller than that of an IGBT, and when Q3 turns off, the entire hybrid switching structure will also turn off completely.
In summary, in the series-parallel hybrid switch structure of the SiC MOSFET, the Si IGBT and the Si MOSFET, the rated current of the Si IGBT is 2 to 3 times that of the SiC MOSFET, the rated voltage of the Si MOSFET is lower than 30V, the cost of the Si MOSFET with lower rated voltage is lower, the on-resistance is smaller, and the on-loss is lower. In the turn-off process of the hybrid switch structure, the turn-off signals of the three devices are sent in sequence of Si MOSFET, si IGBT and SiC MOSFET, and the time interval between the turn-off signals is 0.2us to 0.3us.
Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention. It will be clearly understood by those skilled in the art that, for convenience and brevity of description, specific working procedures of the apparatus and device described above may refer to corresponding procedures in the foregoing method embodiments, which are not described herein again.
In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, and for example, the division of the modules is merely a logical function division, and there may be additional divisions when actually implemented, for example, multiple modules or components may be combined or integrated into another system, or some features may be omitted or not performed.
The modules described as separate components may or may not be physically separate, and components shown as modules may or may not be physical modules, i.e., may be located in one place, or may be distributed over a plurality of modules. Some or all of the modules can be selected according to actual needs to achieve the purpose of the embodiment of the invention.
In addition, each functional module in the embodiment of the present invention may be integrated in one processing module, or each module may exist alone physically, or two or more modules may be integrated in one module. The foregoing description is only of the preferred embodiments of the present application and is presented as a description of the principles of the technology being utilized. It will be appreciated by persons skilled in the art that the scope of the invention referred to in this application is not limited to the specific combinations of features described above, but it is intended to cover other embodiments in which any combination of features described above or equivalents thereof is possible without departing from the spirit of the invention. Such as the above-described features and technical features having similar functions (but not limited to) disclosed in the present application are replaced with each other.
It should be understood that, the sequence numbers of the steps in the summary and the embodiments of the present invention do not necessarily mean the order of execution, and the execution order of the processes should be determined by the functions and the internal logic, and should not be construed as limiting the implementation process of the embodiments of the present invention.
Claims (5)
1. The mixed switch structure of the SiC MOSFET, the Si IGBT and the Si MOSFET is characterized by comprising two parallel current branches, wherein the first current branch is formed by connecting a field effect transistor Q1 and a diode D1 in parallel, and the second current branch is formed by connecting a field effect transistor Q2 and the diode D2 in parallel, connecting a field effect transistor Q3 and the diode D3 in parallel and then connecting the two parallel current branches in series;
in the t0-t1 stage, Q1, Q2 and Q3 will receive the opening signal of the driving circuit at time t0 at the same time, the two current branches bear the load current together, after Q1, Q2 and Q3 are fully conducted, the current ratio of the first current branch and the second current branch is 1:2 to 1:3;
in the stage t1-t2, Q3 starts to be turned off at the moment t1, the second current branch starts to transfer to the first current branch, and Q2 is turned off at zero voltage because Q1 is always in an on state at the moment;
in the stage t2-t3, Q2 starts to be turned off at the moment t2, and as the Q3 of the second current branch is turned off before and Q1 is still in a conducting state, Q3 is zero voltage and zero current is turned off;
in the stage t3-t4, Q3 starts to be turned off at the moment t3, and after Q3 is turned off, the whole hybrid switch structure is also completely turned off;
in the hybrid switch structure, Q1 is a SiC MOSFET with rated voltage of 1200V or 1700V, Q2 is a Si IGBT with the same voltage level as the SiC MOSFET, and Q3 is a low-voltage Si MOSFET with the same current level as Q2.
2. The hybrid switching structure of claim 1 wherein the rated current of Q1 is 1/3 to 1/2 of Q2.
3. The hybrid switching structure of claim 1 wherein D1, D2 and D3 are fast recovery diodes that match the voltage and current levels corresponding to Q1, Q2 and Q3.
4. The hybrid switch fabric of claim 1, wherein the three device off signals are sent in sequence Q3, Q2, Q1.
5. The hybrid switching structure of claim 1 wherein the time interval between turn-off signals is 0.2us to 0.3us.
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EP2819142A2 (en) * | 2013-06-28 | 2014-12-31 | Hamilton Sundstrand Corporation | Solid state circuit-breaker switch devices |
JP2019004656A (en) * | 2017-06-19 | 2019-01-10 | 富士電機株式会社 | Bidirectional switch and driving method of the same |
CN110634817A (en) * | 2019-09-25 | 2019-12-31 | 湖南大学 | Packaging structure of hybrid power module composed of IGBT and MOSFET |
CN112511028A (en) * | 2020-11-26 | 2021-03-16 | 湖南大学 | Flying capacitor multi-level inverter based on GaN and Si device mixing and control method thereof |
CN112805830A (en) * | 2019-04-01 | 2021-05-14 | 富士电机株式会社 | Semiconductor module |
CN112910244A (en) * | 2021-01-28 | 2021-06-04 | 三峡大学 | Single-phase three-level power factor correction circuit of hybrid bridge arm |
CN114301269A (en) * | 2021-12-15 | 2022-04-08 | 南京航空航天大学 | Grid optimization control method and device of SiC/Si hybrid parallel device |
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WO2020172031A1 (en) * | 2019-02-21 | 2020-08-27 | North Carolina State University | Power devices having tunable saturation current clamps therein that support improved short-circuit capability and methods of operating same |
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Patent Citations (7)
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EP2819142A2 (en) * | 2013-06-28 | 2014-12-31 | Hamilton Sundstrand Corporation | Solid state circuit-breaker switch devices |
JP2019004656A (en) * | 2017-06-19 | 2019-01-10 | 富士電機株式会社 | Bidirectional switch and driving method of the same |
CN112805830A (en) * | 2019-04-01 | 2021-05-14 | 富士电机株式会社 | Semiconductor module |
CN110634817A (en) * | 2019-09-25 | 2019-12-31 | 湖南大学 | Packaging structure of hybrid power module composed of IGBT and MOSFET |
CN112511028A (en) * | 2020-11-26 | 2021-03-16 | 湖南大学 | Flying capacitor multi-level inverter based on GaN and Si device mixing and control method thereof |
CN112910244A (en) * | 2021-01-28 | 2021-06-04 | 三峡大学 | Single-phase three-level power factor correction circuit of hybrid bridge arm |
CN114301269A (en) * | 2021-12-15 | 2022-04-08 | 南京航空航天大学 | Grid optimization control method and device of SiC/Si hybrid parallel device |
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