Control circuit of power module and electronic equipment
Through a single power supply control circuit and fast recovery diode protection circuit, the driving voltage requirements and circuit failure problems of IGBT switch tubes are solved, and cost reduction and circuit protection are achieved.
Patent Information
- Application Number
- CN202422265171.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-14
- Publication Date
- 2025-07-11
- Estimated Expiration
- 2034-09-14
AI Technical Summary
In the prior art, IGBT switch tubes require multiple independent driving circuits and isolated power supplies, resulting in high costs and circuit failure may occur when the IGBT downtube fails.
The control circuit powered by a single power supply is adopted to realize the driving voltage requirements of the IGBT upper and lower tubes through the first diode, and protect the circuit when the IGBT lower tube fails, and uses a fast recovery diode to limit the return high voltage.
It reduces costs, meets the driving voltage requirements of the IGBT upper and lower tubes, and protects the circuit when the IGBT lower tube fails to prevent high-voltage return.
Smart Images
Figure CN223093671U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electronic circuits, and particularly to a control circuit for a power module and an electronic device. Background Art
[0002] For a power module including multiple IGBT (Insulated Gate Bipolar Transistor) switching tubes, multiple IGBT switching tubes often require multiple independent drive circuits. In order to ensure that the drive circuits of each switching tube do not interfere with each other and can provide correct drive signals, multiple isolated power supplies are often used.
[0003] When a bootstrap circuit is used instead of an isolated power supply, different requirements exist for the drive voltage of the upper IGBT tube and the drive voltage of the lower IGBT tube. Two isolated power supplies are often used to provide drive signals respectively, but this technical solution has a high cost. Summary of the Utility Model
[0004] To solve the above problems, this application provides a control circuit for a power module and an electronic device, which can use a single power supply to simultaneously supply power to the first control unit and the second control unit, reducing costs.
[0005] One technical solution adopted by this application is: to provide a control circuit for a power module, the power module includes a first control unit, a second control unit, a first power tube, a second power tube, and a first bootstrap unit. The first control unit is connected to the control end of the first power tube, the second control unit is connected to the control end of the second power tube, the first end of the first bootstrap unit is connected to the low-voltage side digital power supply end of the first control unit, and the second end of the first bootstrap unit is connected to the first high-voltage side power supply end of the first control unit. The control circuit of the power module includes: a power supply; a second bootstrap unit, the first end of the second bootstrap unit is connected to the power supply, and the second end of the second bootstrap unit is connected to the first high-voltage side power supply end of the first control unit; a charge and discharge unit, the first end of the charge and discharge unit is connected to the first high-voltage side power supply end of the first control unit, and the second end of the charge and discharge unit is connected to the second high-voltage side power supply end of the first control unit; a first diode, the anode of the first diode is connected to the power supply, and the cathode of the first diode is connected to the low-voltage side digital power supply end of the second control unit.
[0006] In one embodiment, the first diode is a fast-recovery diode.
[0007] In one embodiment, the charge and discharge unit includes: a first capacitor, the first end of the first capacitor is connected to the second end of the second bootstrap unit, and the second end of the first capacitor is connected to the second high-voltage side power supply end of the first control unit; a second capacitor, the first end of the second capacitor is connected to the first end of the first capacitor, and the second end of the second capacitor is connected to the second end of the first capacitor.
[0008] In one embodiment, the first capacitor is a common capacitor and the second capacitor is an electrolytic capacitor.
[0009] In one embodiment, the second bootstrap unit includes a second diode. The anode of the second diode is connected to the power supply, and the cathode of the second diode is connected to the first high-voltage side power supply terminal of the first control unit.
[0010] In one embodiment, the second bootstrap unit further includes a first resistor. The first end of the first resistor is connected to the power supply, and the second end of the first resistor is connected to the anode of the second diode.
[0011] In one embodiment, the control circuit of the power module further includes a voltage stabilizing unit. The first end of the voltage stabilizing unit is connected to the cathode of the first diode, and the second end of the voltage stabilizing unit is grounded.
[0012] In one embodiment, the voltage stabilizing unit includes: a third capacitor, the first end of the third capacitor is connected to the cathode of the first diode, and the second end of the third capacitor is grounded; a fourth capacitor, the first end of the fourth capacitor is connected to the cathode of the first diode, and the second end of the fourth capacitor is grounded.
[0013] In one embodiment, the third capacitor is a common capacitor and the fourth capacitor is an electrolytic capacitor.
[0014] The present application further provides an electronic device, which includes: a power module, the power module includes a first control unit, a second control unit, a first power transistor, a second power transistor and a first bootstrap unit. The first control unit is connected to the first power transistor, the second control unit is connected to the second power transistor. The first end of the first power transistor is connected to the first power input terminal, the first end of the second power transistor is connected to the second end of the first power transistor, the second end of the second power transistor is connected to the second power input terminal. The first end of the first bootstrap unit is connected to the low-voltage side digital power supply terminal of the first control unit, and the second end of the first bootstrap unit is connected to the first high-voltage side power supply terminal of the first control unit; a control circuit, connected to the power module, and the control circuit is the control circuit of the power module as described above.
[0015] The control circuit of the power module provided by the present application includes: a power supply; a second bootstrap unit, the first end of the second bootstrap unit is connected to the power supply, and the second end of the second bootstrap unit is connected to the first high-voltage side power supply terminal of the first control unit; a charge and discharge unit, the first end of the charge and discharge unit is connected to the first high-voltage side power supply terminal of the first control unit, and the second end of the charge and discharge unit is connected to the second high-voltage side power supply terminal of the first control unit; a first diode, the anode of the first diode is connected to the power supply, and the cathode of the first diode is connected to the low-voltage side digital power supply terminal of the second control unit. In this way, a single power supply can be used to simultaneously meet the requirements of the driving voltage of the IGBT upper transistor and the driving voltage of the IGBT lower transistor, and can protect the circuit after the IGBT lower transistor fails. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.
[0017] Among them:
[0018] Figure 1 is a schematic structural diagram of the control circuit of the existing power module;
[0019] Figure 2 is a schematic structural diagram of the second embodiment of the control circuit of the power module provided by the present application;
[0020] Figure 3 is a schematic structural diagram of the third embodiment of the control circuit of the power module provided by the present application;
[0021] Figure 4 is a schematic structural diagram of the fourth embodiment of the control circuit of the power module provided by the present application;
[0022] Figure 5 is a schematic structural diagram of an embodiment of the electronic device provided by the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0023] The following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. It can be understood that the specific embodiments described herein are only used to explain the present application, rather than limiting the present application. Additionally, it should be noted that for the convenience of description, only the parts related to the present application rather than all the structures are shown in the drawings. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.
[0024] The terms "first", "second", etc. in the present application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally further include steps or units not listed, or may optionally further include other steps or units inherent to these processes, methods, products, or devices.
[0025] References herein to "embodiments" mean that the particular features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.
[0026] As Figure 1 shown, Figure 1 is a schematic diagram of the control circuit structure of an existing power module.
[0027] In order to meet the driving voltage requirements of the IGBT upper transistor and the IGBT lower transistor, two BUCK power supplies are required. The IGBT upper transistor uses a 16.5V BUCK power supply, and the IGBT lower transistor uses a 15V BUCK power supply, respectively meeting the voltage requirements of 13.5 - 18.5V for the IGBT upper transistor and 13.5 - 16.5V for the IGBT lower transistor. This control circuit uses external bootstrap and internal bootstrap. After the IGBT lower transistor is turned on, the charging capacitor is charged through the external bootstrap path and the internal bootstrap path respectively. Although this solution can meet the voltage requirements of the IGBT upper transistor and the IGBT lower transistor, using two BUCK power supplies increases the cost, and when the IGBT lower transistor fails, it will cause the three poles of the gate, collector, and emitter of the IGBT lower transistor to conduct, and the high voltage will pass from the P terminal along the IGBT upper transistor through the failed IGBT lower transistor, resulting in the high voltage being strung to the power supply and causing the circuit to fail.
[0028] Referring to Figure 2 , Figure 2 is a schematic diagram of the structure of the second embodiment of the control circuit of the power module provided by the present application. Among them, the control circuit 100 is used to supply power to the power module 200. The control circuit 100 of the power module includes: a power supply 10, a second bootstrap unit 20, a charge and discharge unit 30, and a first diode D1.
[0029] Among them, the power module 200 includes a first control unit 210, a second control unit 220, a first power transistor Q1, a second power transistor Q2, and a first bootstrap unit 230. The first control unit 210 is connected to the first power transistor Q1, the second control unit 220 is connected to the second power transistor Q2, the first end of the first bootstrap unit 230 is connected to the low-voltage side digital power supply terminal VCC1 of the first control unit 210, and the second end of the first bootstrap unit 230 is connected to the first high-voltage side power supply terminal VB of the first control unit 210.
[0030] Among them, the first end of the second bootstrap unit 20 is connected to the power supply 10, and the second end of the second bootstrap unit 20 is connected to the first high-voltage side power supply terminal VB of the first control unit 210; the first end of the charge and discharge unit 30 is connected to the first high-voltage side power supply terminal VB of the first control unit 210, and the second end of the charge and discharge unit 30 is connected to the second high-voltage side power supply terminal VS of the first control unit 210; the anode of the first diode D1 is connected to the power supply 10, and the cathode of the first diode D1 is connected to the low-voltage side digital power supply terminal VCC2 of the second control unit 220.
[0031] Specifically, the power module can be an IPM (Intelligent Power Module) power module, which is an advanced power device integrating the power switching device IGBT. The bootstrap circuit, also known as the boost circuit, is a circuit technology that uses electronic components (such as bootstrap boost diodes and bootstrap boost capacitors) to superimpose the capacitor discharge voltage and the power supply voltage to achieve voltage increase. When a bootstrap capacitor is used instead of an isolated power supply, its power supply capacity is limited and is only suitable for devices with relatively low power supply current requirements like IPM. The requirements for the drive voltages of the lower IGBT and the upper IGBT in the IPM are different. The upper IGBT voltage requires rapid charging to an appropriate voltage, which requires a relatively high power supply voltage. However, the drive voltage of the lower IGBT requires stability and preferably does not exceed 16.5V. It is difficult to simultaneously meet the requirements of the upper IGBT voltage and the lower IGBT voltage using a single power supply. Using two power supplies will increase costs, and when the lower IGBT fails, high voltage flows back from the upper IGBT through the failed lower IGBT to the power supply, causing circuit failure.
[0032] In one embodiment, by adding the first diode D1 to the lower IGBT drive circuit, the voltage drop of the first diode D1 itself is utilized to simultaneously meet the requirements of the upper IGBT and the lower IGBT for drive voltages using a single power supply; and because the first diode D1 has unidirectional conductivity, when the lower IGBT fails, it can limit the backflow high voltage and achieve protection of the power supply.
[0033] Optionally, the first diode D1 is a fast recovery diode. A fast recovery diode is a semiconductor diode with good switching characteristics and short reverse recovery time, which can quickly recover from the reverse blocking state to the forward conduction state. In one embodiment, a 600V or 1000V fast recovery diode can be used. When the first diode D1 is reverse-biased, it can withstand a high voltage of 600V or 1000V, thereby protecting the power supply when the lower IGBT fails.
[0034] Refer to Figure 3 , Figure 3It is a schematic structural diagram of the third embodiment of the control circuit of the power module provided by this application. The control circuit 100 of the power module includes: a power supply 10, a second bootstrap unit 20, a charge and discharge unit 30, and a first diode D1.
[0035] Among them, the first end of the second bootstrap unit 20 is connected to the power supply 10, and the second end of the second bootstrap unit 20 is connected to the first high-voltage side power supply terminal VB of the first control unit 210; the first end of the charge and discharge unit 30 is connected to the first high-voltage side power supply terminal VB of the first control unit 210, and the second end of the charge and discharge unit 30 is connected to the second high-voltage side power supply terminal VS of the first control unit 210; the anode of the first diode D1 is connected to the power supply 10, and the cathode of the first diode D1 is connected to the low-voltage side digital power supply terminal VCC2 of the second control unit 220.
[0036] Optionally, the second bootstrap unit 20 includes a second diode D2, the anode of the second diode D2 is connected to the power supply 10, and the cathode of the second diode D2 is connected to the first high-voltage side power supply terminal VB of the first control unit 210.
[0037] Optionally, the second bootstrap unit 20 further includes a first resistor R1, the first end of the first resistor R1 is connected to the power supply 10, and the second end of the first resistor R1 is connected to the anode of the second diode D2.
[0038] Optionally, the charge and discharge unit 30 includes: a first capacitor C1, the first end of the first capacitor C1 is connected to the second end of the second bootstrap unit 20, and the second end of the first capacitor C1 is connected to the second high-voltage side power supply terminal VS of the first control unit 210; a second capacitor C2, the first end of the second capacitor C2 is connected to the first end of the first capacitor C1, and the second end of the second capacitor C2 is connected to the second end of the first capacitor C1.
[0039] Among them, the first capacitor C1 is a common capacitor, and the second capacitor C2 is an electrolytic capacitor.
[0040] In an application scenario, the power supply 10 uses a 16.3V BUCK power supply. The first power transistor Q1 serves as the upper IGBT transistor, and its voltage requirement range is 13.5 - 18.5V. The second power transistor Q2 serves as the lower IGBT transistor, and its voltage requirement does not exceed 16.3V. When the second power transistor Q2 conducts, the power supply 10 charges the first capacitor C1 through the first resistor R1 and the second diode D2, and simultaneously charges the second capacitor C2 through the first diode D1 and the first bootstrap unit 230 inside the power module. The first capacitor C1 and the second capacitor C2 can be fully charged in a very short time through the two charging circuits for driving the first power transistor Q1. At the same time, when the power supply 10 passes through the first diode D1, the power supply voltage drops by about 0.5V due to the voltage drop of the first diode D1, so that the driving voltage of the second power transistor Q2 does not exceed 16.3V. Due to the boosting effect of the bootstrap circuit, the driving voltage requirement of the first power transistor Q1 can also be met. The first diode D1 and the second diode D2 can also prevent current backflow and are used for circuit protection.
[0041] Refer to Figure 4 , Figure 4 FIG. is a schematic structural diagram of the fourth embodiment of the control circuit of the power module provided by the present application. The control circuit 100 of the power module includes: a power supply 10, a second bootstrap unit 20, a charge and discharge unit 30, and a first diode D1.
[0042] Among them, the first end of the second bootstrap unit 20 is connected to the power supply 10, and the second end of the second bootstrap unit 20 is connected to the first high-voltage side power supply terminal VB of the first control unit 210; the first end of the charge and discharge unit 30 is connected to the first high-voltage side power supply terminal VB of the first control unit 210, and the second end of the charge and discharge unit 30 is connected to the second high-voltage side power supply terminal VS of the first control unit 210; the anode of the first diode D1 is connected to the power supply 10, and the cathode of the first diode D1 is connected to the low-voltage side digital power supply terminal VCC2 of the second control unit 220.
[0043] Figure 4 The control circuit 100 of the power module shown is the same as Figure 3 The main difference between the control circuit 100 of the power module shown and Figure 3 is that the relevant descriptions of the components added to the voltage stabilizing unit 40, the second resistor R2, and the third resistor R3 are added. Therefore, the components added to the voltage stabilizing unit 40, the second resistor R2, and the third resistor R3 will be mainly described below. For other components in the control circuit 100 of the power module, please refer to Figure 4 The description of the charge and discharge unit 30 in Figure 3 can be referred to, and the description thereof will not be repeated here.
[0044] Optionally, the control circuit 100 of the power module further includes a voltage stabilizing unit 40. The first end of the voltage stabilizing unit 40 is connected to the cathode of the first diode D1, and the second end of the voltage stabilizing unit 40 is grounded.
[0045] Optionally, the voltage stabilizing unit 40 includes: a third capacitor C3, the first end of the third capacitor C3 is connected to the cathode of the first diode D1, and the second end of the third capacitor C3 is grounded; a fourth capacitor C4, the first end of the fourth capacitor C4 is connected to the cathode of the first diode D1, and the second end of the fourth capacitor C4 is grounded. Among them, the third capacitor is a common capacitor, and the fourth capacitor is an electrolytic capacitor.
[0046] Among them, the power module includes a first control unit 210, a second control unit 220, a first power transistor Q1, a second power transistor Q2, and a first bootstrap unit 230. The high-level output terminal HO of the first control unit 210 is connected to the control terminal of the first power transistor Q1, the low-level output terminal LO of the second control unit 220 is connected to the control terminal of the second power transistor Q2, the first bootstrap unit 230 includes a third diode D11 and a fourth resistor R11, the first end of the fourth resistor R11 is connected to the low-voltage side digital power supply terminal VCC1 of the first control unit 210, the second end of the fourth resistor R11 is connected to the anode of the third diode D11, and the cathode of the third diode D11 is connected to the first high-voltage side power supply terminal VB of the first control unit 210. The common terminal COM1 of the first control unit 210 is connected to the common terminal COM2 of the second control unit 220 and the voltage selection terminal VSL of the second control unit 220, and the common terminal COM2 of the second control unit 220 is connected to the power supply 10 and the ground.
[0047] Refer to Figure 5 , Figure 5 FIG. is a schematic structural diagram of an embodiment of an electronic device provided by the present application. The electronic device 1000 includes: a control circuit 100 and a power module 200. The power module 200 includes a first control unit 210, a second control unit 220, a first power transistor Q1, a second power transistor Q2, and a first bootstrap unit 230. The first control unit 210 is connected to the first power transistor Q1, the second control unit 220 is connected to the second power transistor Q2, the first end of the first power transistor Q1 is connected to the first power input terminal P, the first end of the second power transistor Q2 is connected to the second end of the first power transistor Q1, the second end of the second power transistor Q2 is connected to the second power input terminal N, the first end of the first bootstrap unit 230 is connected to the low-voltage side digital power supply terminal VCC of the first control unit 210, and the second end of the first bootstrap unit 230 is connected to the first high-voltage side power supply terminal VB of the first control unit 210; the control circuit 100 is connected to the power module 200, and the control circuit 100 is the control circuit 100 of the power module 200 as described above, which will not be elaborated here.
[0048] In several embodiments provided in the present application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the modules or units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.
[0049] The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.
[0050] In addition, in each embodiment of the present application, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated units can be implemented in the form of hardware or in the form of software functional units.
[0051] The above is only the embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present application.
Claims
1. A control circuit for a power module, characterized in that, The power module includes a first control unit, a second control unit, a first power transistor, a second power transistor, and a first bootstrap unit. The first control unit is connected to the control terminal of the first power transistor. The second control unit is connected to the control terminal of the second power transistor. The first end of the first bootstrap unit is connected to the low-side digital power supply terminal of the first control unit. The second end of the first bootstrap unit is connected to the first high-side power supply terminal of the first control unit. The control circuit of the power module includes: A power supply; A second bootstrap unit, the first end of the second bootstrap unit is connected to the power supply, and the second end of the second bootstrap unit is connected to the first high-side power supply terminal of the first control unit; A charge and discharge unit, the first end of the charge and discharge unit is connected to the first high-side power supply terminal of the first control unit, and the second end of the charge and discharge unit is connected to the second high-side power supply terminal of the first control unit; A first diode, the anode of the first diode is connected to the power supply, and the cathode of the first diode is connected to the low-side digital power supply terminal of the second control unit.
2. The control circuit of the power module according to claim 1, wherein The first diode is a fast recovery diode.
3. The control circuit of the power module according to claim 1, characterized in that, The charge and discharge unit includes: A first capacitor, the first end of the first capacitor is connected to the second end of the second bootstrap unit, and the second end of the first capacitor is connected to the second high-side power supply terminal of the first control unit; A second capacitor, the first end of the second capacitor is connected to the first end of the first capacitor, and the second end of the second capacitor is connected to the second end of the first capacitor.
4. The control circuit of the power module according to claim 3, characterized in that, The first capacitor is a general capacitor, and the second capacitor is an electrolytic capacitor.
5. The control circuit of the power module according to claim 1, characterized in that, The second bootstrap unit includes a second diode, the anode of the second diode is connected to the power supply, and the cathode of the second diode is connected to the first high-side power supply terminal of the first control unit.
6. The control circuit of the power module according to claim 5, characterized in that, The second bootstrap unit further includes a first resistor, the first end of the first resistor is connected to the power supply, and the second end of the first resistor is connected to the anode of the second diode.
7. The control circuit of the power module according to claim 1, characterized in that, The control circuit of the power module further includes a voltage stabilizing unit, the first end of the voltage stabilizing unit is connected to the cathode of the first diode, and the second end of the voltage stabilizing unit is grounded.
8. The control circuit of the power module according to claim 7, characterized in that, The voltage stabilizing unit includes: A third capacitor, the first end of the third capacitor is connected to the cathode of the first diode, and the second end of the third capacitor is grounded; A fourth capacitor, the first end of the fourth capacitor is connected to the cathode of the first diode, and the second end of the fourth capacitor is grounded.
9. The control circuit of the power module according to claim 8, characterized in that, The third capacitor is a general capacitor, and the fourth capacitor is an electrolytic capacitor.
10. An electronic device, characterized in that, The electronic device includes: Power module, the power module includes a first control unit, a second control unit, a first power transistor, a second power transistor and a first bootstrap unit, the first control unit is connected to the first power transistor, the second control unit is connected to the second power transistor, a first end of the first power transistor is connected to a first power input terminal, a first end of the second power transistor is connected to a second end of the first power transistor, a second end of the second power transistor is connected to a second power input terminal, a first end of the first bootstrap unit is connected to a low-voltage side digital power supply terminal of the first control unit, and a second end of the first bootstrap unit is connected to a first high-voltage side power supply terminal of the first control unit; A control circuit, connected to the power module, the control circuit being the control circuit of the power module according to any one of claims 1-9.