Structure for improving long-term through-current capability after compression joint type IGBT (Insulated Gate Bipolar Translator) failure
By introducing gate drive, control switch and fuse structures into the press-fit IGBT module, the problem of insufficient long-term current carrying capacity after press-fit IGBT failure is solved, and a stable current path and cost optimization are achieved.
Patent Information
- Application Number
- CN202423003800.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-05
- Publication Date
- 2025-11-14
- Estimated Expiration
- 2034-12-05
AI Technical Summary
In existing technologies, press-fit IGBTs are difficult to maintain long-term current carrying capacity after failure, mechanical switches may fail to operate, and turnaround thyristors are expensive and have complex structures, making it impossible to effectively maintain the current path.
The gate drive is connected to the press-fit IGBT module. By controlling the gate current of the IGBT through the parallel connection of the control switch and the drive resistor, combined with the fuse and protection resistor, the gate current of the IGBT is controlled to ensure that the IGBT that has not failed is turned on again, so as to achieve long-term current carrying capacity.
It effectively avoids mechanical switch failure, reduces costs, ensures that undamaged IGBTs can be turned on again, maintains stable long-term current carrying capacity, and avoids device damage and system instability.
Smart Images
Figure CN223553220U_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of flexible DC transmission, specifically relating to a structure that improves the long-term current carrying capacity after the failure of a press-fit IGBT. Background Technology
[0002] Press-fit IGBTs are the primary power semiconductor devices in flexible DC transmission, used to form modular multilevel converter (MMC) modules. These MMCs are then cascaded to form the converter valves for flexible DC transmission. In flexible DC transmission applications, if an MMC module fails, a redundant MMC module is deployed to replace it. The failed module must remain operational, like a conductor inserted into the converter valve to maintain current flow.
[0003] In related technologies, the method to ensure long-term operation after IGBT failure is to use a mechanical switch for bypass switching, switching to another IGBT after one fails, or to add a transition thyristor in the MMC sub-module to bear the system current after the IGBT fails and opens.
[0004] Regarding the aforementioned technologies, mechanical switches may fail to operate and cannot be bypassed after failure. Instead, the system current after the IGBT fails and opens is handled by a transition thyristor. However, transition thyristors differ from conventional thyristors, requiring additional transition voltage screening tests, resulting in high material costs and complex component structures. Utility Model Content
[0005] The technical problem to be solved by this application is to provide a structure that improves the long-term current carrying capacity after the failure of a press-fit IGBT. After some press-fit IGBTs in the MMC module fail, the other unfailed IGBTs can maintain the on state, so that the current can continue to flow.
[0006] A structure for improving the long-term current-carrying capacity of a press-fit IGBT after failure includes:
[0007] Gate drive and press-fit IGBT modules;
[0008] The gate drive is connected to the press-fit IGBT module;
[0009] The gate drive includes a control switch, and the control switch is connected in parallel with a first drive resistor;
[0010] The press-fit IGBT module includes several press-fit IGBTs. Each press-fit IGBT is connected to a fuse between itself and the first driving resistor. One end of the fuse is connected to the gate of the press-fit IGBT, and the other end is connected to the first driving resistor.
[0011] The collectors of each press-fit IGBT are interconnected, and the emitters are interconnected.
[0012] Optionally, a protective resistor is provided between each fuse and the first driving resistor, with one end of the protective resistor connected to the first driving resistor and the other end connected to the fuse.
[0013] Optionally, the control switch is in the off state when there is no failure of the press-fit IGBT.
[0014] Optionally, the control switch is a PCB single-point relay switch.
[0015] Optionally, the voltage of the PCB single-point relay switch is 12V.
[0016] Optionally, the gate voltage of the IGBT is 15V.
[0017] Optionally, the number of press-fit IGBTs is three.
[0018] Optionally, the fuse has a breaking current of 20A.
[0019] Optionally, the resistance of the protection resistor is 10 ohms.
[0020] Optionally, the first driving resistor is further connected to a diode, the negative terminal of which is connected to the first driving resistor and to an external power supply.
[0021] The beneficial effects of this application are:
[0022] 1. By connecting the first driving resistor and the control switch in parallel, and connecting the first, second, and third fuses to the first driving resistor respectively, the first fuse is connected to the gate of the first press-fit IGBT, the second fuse to the gate of the second press-fit IGBT, and the third fuse to the gate of the third press-fit IGBT. By controlling the switch and the first driving resistor, the current flowing into the fuse in the circuit of the failed IGBT is changed, causing the fuse to melt and the failed press-fit IGBT to stop working. Other normal press-fit IGBTs then resume operation. Compared to bypass switching using a mechanical switch, this avoids the situation where the mechanical switch fails to operate, ensuring a stable long-term current carrying capacity.
[0023] 2. By using a control switch, drive resistor, and fuse, multiple press-fit IGBTs can be controlled to disconnect the failed IGBT when it fails, allowing the unfailed press-fit IGBTs to resume operation. This eliminates the need to install a control switch on each branch, saving costs. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of a structure for improving the long-term current carrying capacity of a press-fit IGBT after failure, according to this application.
[0025] Explanation of reference numerals in the attached diagram: 1. Gate driver; 2. Press-fit IGBT module; 3. First drive resistor; 4. Control switch; 5. First press-fit IGBT; 6. Second press-fit IGBT; 7. Third press-fit IGBT; 8. First fuse; 9. Second fuse; 10. Third fuse; 11. Second drive resistor; 12. Third drive resistor; 13. Fourth drive resistor; 14. Diode. Detailed Implementation
[0026] A structure to improve the long-term current carrying capacity of a press-fit IGBT after failure, such as Figure 1 As shown, it includes:
[0027] Gate driver 1 and press-fit IGBT module 2.
[0028] Gate driver 1 is connected to press-fit IGBT module 2.
[0029] The gate drive 1 includes a control switch 4, which is connected in parallel with a first drive resistor 3.
[0030] The press-fit IGBT module 2 includes several press-fit IGBTs. Each press-fit IGBT is connected to a fuse between itself and the first driving resistor 3. One end of the fuse is connected to the gate of the press-fit IGBT, and the other end is connected to the first driving resistor 3.
[0031] The collectors of each press-fit IGBT are interconnected, and the emitters are interconnected.
[0032] A protective resistor is provided between each fuse and the first driving resistor 3. One end of the protective resistor is connected to the first driving resistor 3, and the other end is connected to the fuse.
[0033] When there is no failure of the press-fit IGBT, control switch 4 is in the off state.
[0034] Control switch 4 is a PCB single-point relay switch, and the voltage of the PCB single-point relay switch is 12V.
[0035] The gate voltage of the IGBT is 15V.
[0036] The fuse has a breaking current of 20A.
[0037] The number of press-fit IGBTs is 3.
[0038] The protective resistor has a resistance of 10 ohms.
[0039] The first driving resistor 3 is also connected to a diode 14. The cathode of the diode 14 is connected to the first driving resistor 3, and the cathode of the diode 14 is connected to an external power supply.
[0040] Taking a connection of three press-fit IGBTs as an example, the fuses include a first fuse 8, a second fuse 9, and a third fuse 10; the press-fit IGBTs include a first press-fit IGBT 5, a second press-fit IGBT 6, and a third press-fit IGBT 7; and the protection resistors include a second drive resistor 11, a third drive resistor 12, and a fourth drive resistor 13.
[0041] The gate driver 1 includes a first driving resistor 3 and a control switch 4, which are connected in parallel.
[0042] The first fuse 8, the second fuse 9, and the third fuse 10 are respectively connected to the first driving resistor 3. The first fuse 8 is connected to the gate of the first pressure-fit IGBT 5, the second fuse 9 is connected to the gate of the second pressure-fit IGBT 6, and the third fuse 10 is connected to the gate of the third pressure-fit IGBT 7.
[0043] The emitter of the first crimped IGBT 5 is connected to the emitter of the second crimped IGBT 6 and the emitter of the third crimped IGBT 7, respectively.
[0044] The collector of the first press-fit IGBT 5 is connected to the collector of the second press-fit IGBT 6 and the collector of the third press-fit IGBT 7, respectively.
[0045] A second driving resistor 11 is provided between the first driving resistor 3 and the first fuse 8.
[0046] A third driving resistor 12 is provided between the first driving resistor 3 and the second fuse 9.
[0047] A fourth driving resistor 13 is provided between the first driving resistor 3 and the second fuse 9.
[0048] When the first crimped IGBT 5, the second crimped IGBT 6, and the third crimped IGBT 7 are not faulty, the control switch 4 is in the off state.
[0049] The first driving resistor 3 is also connected to a diode 14. The negative terminal of the diode 14 is connected to the driving resistor and to an external power supply.
[0050] Specifically, under normal operating conditions, since the PCB single-point relay switch is in the open state, the current flows through the positive terminal of diode 14 to the first driving resistor 3, and then from the first driving resistor 3 to the second driving resistor 11, the third driving resistor 12, and the fourth driving resistor 13 respectively. The current flowing through the second driving resistor 11 then flows through the first fuse 8 to the gate of the first pressure-fit IGBT 5, turning on the first pressure-fit IGBT 5. The current flowing through the third driving resistor 12 then flows through the second fuse 9 to the gate of the second pressure-fit IGBT 6, turning on the second pressure-fit IGBT 6. The current flowing through the fourth driving resistor 13 then flows through the third fuse 10 to the third pressure-fit IGBT 7, turning on the third pressure-fit IGBT 7.
[0051] When one of the press-fit IGBTs fails, closing the single-point relay switch short-circuits the first drive resistor 3, and the gate resistance of the failed press-fit IGBT decreases. Therefore, the gate current of the failed IGBT rapidly increases, melting the corresponding fuse. For example, if the first press-fit IGBT 5 fails, the first fuse 8 will melt, causing the branch that caused the failure to disconnect. The gate voltage of the other IGBTs will then be raised back to V, triggering the other non-failed IGBTs to turn on, sharing the continuous current after the device failure. This fundamentally solves the various uncertainties caused by the continuous current flow of the failed chip. When the failed chip / failed sub-unit carries a large current, the heat generation increases sharply, and the temperature rises rapidly. Furthermore, due to the energy release during failure, the casing of the press-fit device may be damaged, allowing air to enter. Under the influence of high temperature, oxygen, and moisture, the internal interfaces of the sub-unit will gradually corrode, oxidize, and consume, resulting in more severe heat generation and a further decrease in current-carrying capacity. In this situation, the device may exhibit high resistance or an open circuit state, affecting system operation and making it difficult to guarantee a stable long-term current-carrying capacity. A single-point relay can be controlled to open and close using a microcontroller and comparators.
[0052] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of protection of this application is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of one or more embodiments of this application as described above, which are not provided in detail for the sake of brevity.
[0053] One or more embodiments in this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments in this application should be included within the protection scope of this application.
Claims
1. A structure for improving the long-term current-carrying capacity of a press-fit IGBT after failure, characterized in that, include: Gate drive (1) and press-fit IGBT module (2); The gate driver (1) is connected to the press-fit IGBT module (2); The gate drive (1) includes a control switch (4), which is connected in parallel with a first drive resistor (3); The press-fit IGBT module (2) includes several press-fit IGBTs. Each press-fit IGBT is connected to a fuse between itself and the first driving resistor (3). One end of the fuse is connected to the gate of the press-fit IGBT, and the other end is connected to the first driving resistor (3). The collectors of each press-fit IGBT are interconnected, and the emitters are interconnected.
2. The structure for improving the long-term current carrying capacity after failure of a press-fit IGBT as described in claim 1, characterized in that, A protective resistor is provided between each fuse and the first driving resistor (3), with one end of the protective resistor connected to the first driving resistor (3) and the other end connected to the fuse.
3. The structure for improving the long-term current carrying capacity after failure of a press-fit IGBT as described in claim 1, characterized in that, When there is no failure of the press-fit IGBT, the control switch (4) is in the off state.
4. The structure for improving the long-term current carrying capacity after failure of a press-fit IGBT as described in claim 1, characterized in that, The control switch (4) is a PCB single-point relay switch.
5. The structure for improving the long-term current carrying capacity after failure of a press-fit IGBT as described in claim 4, characterized in that, The voltage of the PCB single-point relay switch is 12V.
6. The structure for improving the long-term current carrying capacity after failure of a press-fit IGBT as described in claim 1, characterized in that, The gate voltage of the press-fit IGBT is 15V.
7. The structure for improving the long-term current carrying capacity after failure of a press-fit IGBT as described in claim 1, characterized in that, The first driving resistor (3) is also connected to a diode (14), the negative terminal of the diode (14) is connected to the first driving resistor (3), and the negative terminal of the diode (14) is connected to an external power supply.
8. The structure for improving the long-term current carrying capacity after failure of a press-fit IGBT as described in claim 1, characterized in that, The number of press-fit IGBTs is 3.
9. The structure for improving the long-term current carrying capacity after failure of a press-fit IGBT as described in claim 1, characterized in that, The fuse has a breaking current of 20A.
10. The structure for improving the long-term current carrying capacity after failure of a press-fit IGBT as described in claim 2, characterized in that, The resistance of the protection resistor is 10 ohms.