Source-independent IGBT module, totem-pole switch module and their applications

Abstract

The present invention discloses a source-independent IGBT module, whose source is independently led out and not connected to the emitter, and also discloses a totem pole switch module, including: a source-independent IGBT module and a conventional conventional IGBT module, wherein the emitter E1 of the source-independent IGBT module is connected to the collector C2 of the conventional IGBT module to form a midpoint O, and the source S1 of the source-independent IGBT module is connected to the emitter E2 of the conventional IGBT module to form a common emitter E. Also disclosed is an interlocking totem pole switch circuit, in which a clamping circuit is connected between the drain of a first MOS tube and the gate level G2 of the conventional IGBT module. Also disclosed is a power module encapsulated with an interlocking totem pole switch circuit. The switch module can be directly driven by a digital interface of a TTL level such as a single-chip microcomputer, without adding an additional pulse transformer, or other isolation and gate drive circuits, and has a simple structure. It can also ensure that the upper and lower switches cannot be turned on at the same time at any time, which can effectively prevent short-circuit current and surge current.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor switches, and in particular to a source-independent IGBT module, a totem pole switch module and applications thereof. Background Art

[0002] Digitalization, program control and intelligence are the development trends of electronic equipment and switching power supply technology. The core of the switching power supply is the effective combination of semiconductor switches and control technology. Although electronic technology has developed to the era of programmable microchips, the development of semiconductor switches has not yet reached programmability. The input stage of IGBT is composed of field effect tubes, which have the advantages of high input resistance and voltage drive; the output end is a composite triode, which has the advantages of small on-state voltage drop and easy parallel connection. IGBT combines the advantages of triodes and field effect tubes. It is a composite fully controlled semiconductor switch and is widely used in various occasions of switching power supplies. IGBT is often used in groups of two in a totem pole structure with one up and one down in half-bridge, full-bridge and three-phase inverters or frequency converters.

[0003] The existing conventional IGBT module has three electrodes, namely the gate (G), the collector (C) and the emitter (E), wherein the control signal Uge is loaded between the gate and the emitter. By changing the size of Uge, the on (on) or off (off) state between the collector and the emitter is controlled. Since the control end and the output end share an emitter, conventional IGBTs need to be controlled by a pulse transformer or other dedicated gate drive circuits in some applications, such as applications where the emitter is floating or the emitter and the control signal do not share a common ground.

[0004] Therefore, one of the defects of the current totem pole circuit is that the conventional IGBT on the top of the totem pole needs a dedicated pulse transformer for isolation drive, or a dedicated gate drive circuit, and cannot be driven directly by a digital system. In addition, the current totem pole circuit has another defect: if the control is improper, the upper and lower IGBTs are turned on at the same time, causing a short circuit on the DC side power supply, forming a huge surge current, and burning the IGBT. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a source-independent IGBT module, a totem pole switch module and its application, which can enable the digital system to be directly driven by TTL level, realize the digitization, program control and intelligence of the switching power supply; and can also effectively prevent the short circuit and surge current caused by improper control of the totem pole.

[0006] According to an embodiment of the present invention, a source-independent IGBT module includes: a first MOS tube, a first PNP transistor and a first NPN transistor, the drain of the first MOS tube is respectively connected to the base of the first PNP transistor and the collector of the first NPN transistor through a resistor Rb1, the collector of the first PNP transistor is connected to the base of the first NPN transistor, the base of the first NPN transistor is connected to the emitter of the first NPN transistor through a resistor Rbe1, the emitter of the first PNP transistor serves as the collector C1 of the source-independent IGBT module, the gate of the first MOS tube serves as the gate level G1 of the source-independent IGBT module, the emitter of the first NPN transistor serves as the emitter E1 of the source-independent IGBT module, and the source of the first MOS tube serves as the source S1 of the source-independent IGBT module.

[0007] A totem pole switch module according to an embodiment of the present invention includes:

[0008] An IGBT module with independent source and a conventional IGBT module, wherein the conventional IGBT module has three electrodes: a gate G2, a collector C2, and an emitter E2; the emitter E1 of the IGBT module with independent source is connected to the collector C2 of the conventional IGBT module, the source S1 of the IGBT module with independent source is connected to the emitter E2 of the conventional IGBT module, the collector C1 of the IGBT module with independent source is used to connect to the positive pole of a DC power supply, and the emitter E2 of the conventional IGBT module is used to connect to the negative pole of a DC power supply.

[0009] The interlocked totem pole switch circuit according to an embodiment of the present invention comprises: the above-mentioned switch module and a clamp circuit, one end of the clamp circuit is connected to the drain of the first MOS tube, and the other end of the clamp circuit is connected to the gate level G2 of the conventional IGBT module, a resistor Rg is connected in series to the gate level G2 of the conventional IGBT module, and the other end of the resistor Rg is used to connect an external gate drive signal.

[0010] According to the interlocking totem pole power module of the embodiment of the present invention, the substrate and the circuit packaged in the substrate, the circuit is the above-mentioned interlocking totem pole switch circuit, and the substrate is also provided with a collector C, an emitter E, an output stage O, a first gate driver Gu and a second gate driver Gb, the collector C is connected to the collector C1 of the source-independent IGBT module, the emitter E is connected to the emitter E2 of the conventional IGBT module, the output stage O is connected to the common end of the emitter E1 of the source-independent IGBT module and the collector C2 of the conventional IGBT module, the first gate driver Gu is connected to the gate level G1 of the source-independent IGBT module, and the second gate driver Gb is connected to the gate level G2 of the conventional IGBT module through the resistor Rg.

[0011] The totem pole switch module, interlocking totem pole switch circuit and power module according to the embodiments of the present invention have at least the following technical effects:

[0012] In the implementation manner of the present invention, the source of the source-independent IGBT module is independently led out, and the source is not connected to the emitter, and is an independently led-out electrode, so that it becomes an IGBT module with four electrodes, wherein the control signal Ugs is loaded between the gate and the source, and the on or off state between the collector and the emitter is controlled by changing the size of Ugs. In addition to being used in existing IGBT applications, the source-independent IGBT can also be used in applications where the emitter is floating, or the emitter and the control signal do not share a common ground. In these applications, the on and off control of the switch is still simple and convenient.

[0013] The source-independent IGBT module and the conventional IGBT module form a totem pole switch module. The state of the upper switch can be directly controlled by the gate G1 of the source-independent IGBT module and the common ground, and the state of the lower switch can be directly controlled by the gate G2 of the conventional IGBT module and the common ground. The gates of both IGBTs can be directly controlled by the TTL level between the gate and the "common ground", so the TTL level digital interface such as the microcontroller can directly drive the totem pole switch module, without adding additional pulse transformers or isolation and gate drive circuits, and the structure is simple.

[0014] In addition, a clamping circuit is connected between the drain of the first MOS tube and the gate of the field effect tube in the conventional IGBT module. When one of the field effect tubes is turned on, the gate of the other field effect tube is clamped to a low level so that it cannot be turned on by an external control signal. This ensures that the upper and lower switches cannot be turned on at the same time at any time, which can effectively prevent short-circuit current and surge current.

[0015] According to some embodiments of the present invention, a resistor Rbc is provided between the base of the first PNP transistor and the emitter of the first PNP transistor.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0018] Figure 1 1 is a circuit schematic diagram of a source-independent IGBT module in an embodiment of the present invention;

[0019] Figure 2 is a circuit schematic diagram of a totem pole switch module in an embodiment of the present invention;

[0020] Figure 3 is a connection relationship diagram of a clamping circuit in an interlocking totem pole switch circuit in an embodiment of the present invention;

[0021] Figure 4 A pin diagram of an interlocking totem pole power module according to an embodiment of the present invention;

[0022] Figure 5 The figure is a principle block diagram of a full-bridge inverter in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0024] In the description of the invention, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the invention.

[0025] In the description of the invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of the first or the second, it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0026] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0027] refer to Figure 1 A source-independent IGBT module comprises a first MOS tube, a first PNP transistor, and a first NPN transistor. The drain of the first MOS tube is respectively connected to the base of the first PNP transistor and the collector of the first NPN transistor through a resistor Rb1, the collector of the first PNP transistor is connected to the base of the first NPN transistor, the base of the first NPN transistor is connected to the emitter of the first NPN transistor through a resistor Rbe1, the emitter of the first PNP transistor serves as the collector C1 of the source-independent IGBT module, the gate of the first MOS tube serves as the gate level G1 of the source-independent IGBT module, the emitter of the first NPN transistor serves as the emitter E1 of the source-independent IGBT module, and the source of the first MOS tube serves as the source S1 of the source-independent IGBT module. The S electrode of the input stage in the source-independent IGBT module is no longer connected to the E electrode of the output stage internally, so it has four electrodes. In addition to the conventional gate G1, collector C1, and emitter E1, there is also an independent source S1, where the gate drive signal is loaded between the gate G1 and the source S1, represented by UGS. By changing the UGS voltage, the on or off state between the collector C1 and emitter E1 of the source-independent IGBT module is controlled. In addition to being applicable to conventional IGBT modules, even in applications where the emitter is floating or the emitter and the control signal do not share a common ground, the on and off control of the switch is still simple and convenient.

[0028] refer to Figure 2 , a totem pole switch module, including a source-independent IGBT module and a conventional IGBT module,

[0029] refer to Figure 2The naming of the conventional IGBT module is to distinguish it from the source-independent IGBT module. It uses the IGBT module that can be directly purchased on the market. It is composed of a second MOS tube, a second PNP transistor and a second NPN transistor. The conventional IGBT module has three electrodes, namely, gate G2, collector C2 and emitter E2. The gate S2 of the first MOS switch is connected to the emitter E2. The emitter E1 of the source-independent IGBT module is connected to the collector C2 of the conventional IGBT module to form a midpoint O. The source S1 of the source-independent IGBT module is connected to the emitter E2 of the conventional IGBT module to form a common emitter E. The collector C1 of the source-independent IGBT module is used to connect the positive pole of the DC power supply, and the emitter E2 of the conventional IGBT module is used to connect the negative pole of the DC power supply.

[0030] In order to ensure that the source-independent IGBT module is reliably cut off under normal conditions, a resistor Rbc is provided between the base of the first PNP transistor of the source-independent IGBT module and the emitter of the first PNP transistor.

[0031] Therefore, reference Figure 2 In this embodiment, the totem pole switch module has five electrodes facing outward, namely:

[0032] 1) Collector C is the electrode directly connected to collector C1;

[0033] 2) The midpoint O is the electrode where the emitter E1 and the collector C2 are connected together;

[0034] 3) Emitter E, which is the electrode connected to emitter E2 and source S1 of the IGBT module with independent source;

[0035] 4) The upper gate G1 is the gate G1 of the source-independent IGBT module;

[0036] 5) The lower gate G2 is the gate G2 of a conventional IGBT module.

[0037] When used as a switch module, the source-independent IGBT module is used as the upper switch, and the conventional IGBT module is used as the lower switch, wherein the gate drive signal of the gate G2 of the lower switch uses the emitter E2 as the reference ground, and the gate drive signal of the gate G1 of the upper switch also uses the emitter E2 as the reference ground. That is, the reference grounds of the gates of the two semiconductor switches (G1 and G2) are exactly the same, and the two can be directly controlled by the common ground. By controlling the upper switch, that is, the source-independent IGBT module is turned on, the potential of the midpoint O is connected to the positive pole of the DC power supply; by controlling the lower switch, that is, the conventional IGBT module is turned on, the potential of the midpoint O is connected to the negative pole of the DC power supply, so the gates of the two switches can be directly controlled by the TTL level between the gate and the "common ground", so it can be directly driven by DSP devices, single-chip microcomputers, digital chips, and even computer serial ports to realize the digitization, program control and intelligence of the switching power supply. There is no need to add additional pulse transformers or isolation and gate drive circuits.

[0038] The embodiment of the present invention also includes an interlocking totem pole switch circuit, comprising: the above-mentioned totem pole switch module and the clamping circuit, referring to Figure 3 , one end of the clamping circuit is connected to the drain of the first MOS tube, and the other end of the clamping circuit is connected to the gate level G2 of the conventional IGBT module, that is, the clamping circuit is set between the drain of the first MOS tube and the gate of the second MOS tube, and the drain D1 of the first MOS tube M1 is used to clamp the gate of the second MOS tube M2. A resistor Rg is connected to the gate of the second MOS tube M2, and one end of Rg is connected to the input end of the clamping circuit and the gate of the second MOS tube M2. The external gate drive signal is connected to the other end of Rg to become Gb. In this way, when the source-independent IGBT module is turned on, the clamping circuit will clamp the gate of the second MOS tube M2 at a low level, so that the conventional IGBT module cannot be turned on. Therefore, it can be ensured that the two switches cannot be turned on at the same time at any time, effectively preventing short-circuit current and surge current.

[0039] refer to Figure 4 The embodiment of the present invention also includes an interlocking totem pole power module, including a substrate, in which the above-mentioned interlocking totem pole switch circuit is encapsulated, and five electrodes including a collector C, an emitter E, an output stage O, a first gate drive Gu and a second gate drive Gb are also arranged on the substrate.

[0040] 1) Collector C, usually connected to the positive pole of the DC power supply.

[0041] 2) Emitter E is generally connected to the negative pole of the DC power supply and is also the common reference ground of the two gates. If necessary, an auxiliary emitter can be connected.

[0042] 3) Midpoint O, output pole, is usually connected to the load. When the upper switch is turned on, the midpoint is equivalent to being connected to the positive pole of the power supply; when the lower switch is turned on, the midpoint is equivalent to being connected to the negative pole of the power supply.

[0043] 4) The upper gate drive electrode Gu controls the switching state of the upper switch by loading the gate drive signal between Gu and E.

[0044] 5) The lower gate drive Gb controls the switching state of the lower switch by loading the gate drive signal between Gb and E.

[0045] The collector C is connected to the collector C1 of the source-independent IGBT module, the emitter E is connected to the emitter E2 of the conventional IGBT module, the output stage O is connected to the common end of the emitter E1 of the source-independent IGBT module and the collector C2 of the conventional IGBT module, the first gate driver Gu is connected to the gate level G1 of the source-independent IGBT module, and the second gate driver Gb is connected to the gate level G2 of the conventional IGBT module through the resistor Rg.

[0046] The interlocking totem pole power module designed by the present invention can be applied to various inverters, frequency converters and the like in digital and programmable control. Figure 5 This is a full-bridge inverter using an interlocking totem pole power module in this embodiment.

[0047] The full-bridge inverter consists of two interlocking totem pole power modules and a control circuit. The four gate drive electrodes Gu1, Gb1, Gu2, and Gb2 of the two interlocking totem pole power modules are directly connected to the digital gate drive controller, the two collector electrodes C11 and C22 are connected to the positive electrode of the DC power supply, and the two emitters E11 and E22 are directly connected to the negative electrode of the power supply. The load Rload is connected between O1 and O2.

[0048] The control circuit can be a digital device such as a single-chip microcomputer, a DSP device, an embedded device, etc. The control circuit controls the high and low levels of Gu1, Gb1, Gu2, and Gb2 through a certain logical relationship, and can obtain AC outputs of various modulation methods, different frequencies, or variable frequencies at both ends of the load. Since the controller uses digital devices, the entire inverter has the advantages of being programmable and adjustable online.

[0049] For a half-bridge inverter, only one interlocking totem pole power module and two identical capacitors are needed to form a half-bridge inverter circuit. Three interlocking totem pole power modules and corresponding digital controllers can be used to achieve three-phase power inversion.

[0050] In summary, the switch module provided by the present invention can be directly driven by a TTL level digital interface such as a single-chip microcomputer, without adding additional pulse transformers or isolation and gate drive circuits, and has a simple structure.

[0051] In addition, the interlocking totem pole switch circuit and the interlocking totem pole power module provided by the present invention can also ensure that the upper and lower switches cannot be turned on at the same time at any time, which can effectively prevent short-circuit current and surge current.

[0052] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present invention.

Claims

1. An interlocking totem pole full-bridge inverter, comprising: Two interlocking totem-pole power modules and a digital door drive controller; The interlocked totem pole power module includes: a substrate and an interlocked totem pole switch circuit packaged in the substrate, the interlocked totem pole switch circuit includes a switch module and a clamp circuit, the switch module includes a source-independent IGBT module and a conventional IGBT module, the source-independent IGBT module includes a first MOS tube, a first PNP transistor and a first NPN transistor, the drain of the first MOS tube is respectively connected to the base of the first PNP transistor and the collector of the first NPN transistor through a resistor Rb1, the collector of the first PNP transistor is connected to the base of the first NPN transistor, the base of the first NPN transistor is connected to the emitter of the first NPN transistor through a resistor Rbe1, the emitter of the first PNP transistor serves as the collector C1 of the source-independent IGBT module, the gate of the first MOS tube serves as the gate level G1 of the source-independent IGBT module, and the emitter of the first NPN transistor serves as the source-independent IGBT module. The emitter E1 of the GBT module, the source of the first MOS tube serves as the source S1 of the IGBT module with independent source; The conventional IGBT module has three electrodes: a gate G2, a collector C2, and an emitter E2. The emitter E1 of the source-independent IGBT module is connected to the collector C2 of the conventional IGBT module. The source S1 of the source-independent IGBT module is connected to the emitter E2 of the conventional IGBT module. The collector C1 of the source-independent IGBT module is used to connect to the positive electrode of a DC power supply. The emitter E2 of the conventional IGBT module is used to connect to the negative electrode of a DC power supply. One end of the clamp circuit is connected to the drain of the first MOS tube, and the other end of the clamp circuit is connected to the gate level G2 of the conventional IGBT module, and a resistor Rg is connected in series to the gate level G2 of the conventional IGBT module; A resistor Rbc is provided between the base of the first PNP transistor and the emitter of the first PNP transistor; The substrate is also provided with a collector C, an emitter E, an output stage O, a first gate driver Gu and a second gate driver Gb, the collector C is connected to the collector C1 of the source-independent IGBT module, the emitter E is connected to the emitter E2 of the conventional IGBT module, the output stage O is connected to the common end of the emitter E1 of the source-independent IGBT module and the collector C2 of the conventional IGBT module, the first gate driver Gu is connected to the gate level G1 of the source-independent IGBT module, and the second gate driver Gb is connected to the gate level G2 of the conventional IGBT module through the resistor Rg; The digital gate drive controller is respectively connected to the first gate drive Gu and the second gate drive Gb of the two interlocking totem pole power modules.

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