Protection device and method for insulated gate bipolar transistor

Abstract

The embodiments of the present application provide a protection device and method for an insulated gate bipolar transistor. The protection device includes: an acquisition circuit that acquires an IGBT drive signal and performs delay processing when the drive signal is at a first level that turns on the IGBT, or when the drive signal changes from a second level that turns off the IGBT to the first level that turns on the IGBT, and outputs a first signal based on the delayed signal and the drive signal; a detection circuit that detects the voltage between the collector and emitter of the IGBT and outputs a second signal based on the voltage and a preset threshold; and a determination circuit that outputs an alarm signal or a protection signal when both the first signal and the second signal are valid. Thus, delay processing can be performed with a simple structure without affecting the drive signal, thereby improving the performance of the IGBT, reducing the cost of the protection circuit, and improving the adjustability of the IGBT control.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a protection device and method for an insulated gate bipolar transistor (IGBT). Background Art

[0002] IGBTs are widely used in power electronics. However, if there is a lack of appropriate protection circuits, IGBTs can be easily damaged. Overcurrent and short circuit (for example, direct connection between the upper and lower bridge arms in the inverter circuit) are common causes of IGBT damage.

[0003] Some IGBT protection circuits have been developed. For example, Reference 1 proposes a dual protection mechanism of hardware interlocking and delay to prevent the IGBT upper and lower bridge arms from being directly connected.

[0004] Reference 1: CN106385009A.

[0005] It should be noted that the above introduction to the background technology is merely for the purpose of providing a clear and complete description of the technical solutions of this application and facilitating understanding by those skilled in the art. Simply because these solutions are described in the background technology section of this application, it should not be assumed that the above technical solutions are well known to those skilled in the art. Summary of the Invention

[0006] However, the inventors found that in the existing technologies including Reference 1, the IGBT drive signal needs to be filtered out of interference and shaped, and then hardware interlocked and delayed. This not only affects the drive signal, but also requires two sets of shaping and delay processing circuits, which reduces the performance of the IGBT and increases the cost of the protection circuit. In addition, the delay processing time is fixed and long, which makes it inconvenient to adjust the control of the IGBT.

[0007] In order to solve at least one of the above problems, the embodiments of the present application provide a protection device and method for an insulated gate bipolar transistor (IGBT), which is expected to improve the performance of the IGBT and reduce the cost of the protection circuit; in addition, the adjustability of the IGBT control is improved.

[0008] According to one aspect of an embodiment of the present application, a protection device for an insulated gate bipolar transistor is provided, comprising:

[0009] an acquisition circuit that acquires a drive signal of the insulated gate bipolar transistor, performs delay processing when the drive signal is at a first level for turning on the insulated gate bipolar transistor, or changes from a second level for turning off the insulated gate bipolar transistor to the first level for turning on the insulated gate bipolar transistor, and outputs a first signal based on the signal after the delay processing and the drive signal;

[0010] A detection circuit is provided for detecting the voltage (V CE ), and output a second signal according to the voltage and a preset threshold; and

[0011] A determination circuit determines that the insulated gate bipolar transistor is abnormal and outputs an alarm signal or a protection signal when both the first signal and the second signal are valid, and determines that the insulated gate bipolar transistor is normal when at least one of the first signal and the second signal is invalid.

[0012] Thus, a delay process is performed according to the level of the IGBT driving signal, a first signal is output according to the signal after the delay process and the driving signal, and a first signal is output according to the V CE and a preset threshold value to output a second signal, and output an alarm signal or a protection signal when both the first signal and the second signal are valid. It can implement overcurrent protection and / or short-circuit protection by delay processing with a simple structure without affecting the drive signal. In addition, it can also improve the performance of the IGBT and reduce the cost of the protection circuit, and improve the adjustability of the IGBT control.

[0013] In some embodiments, the acquisition circuit does not perform the delay processing when the driving signal is at the second level that turns off the insulated gate bipolar transistor, or changes from the first level that turns on the insulated gate bipolar transistor to the second level that turns off the insulated gate bipolar transistor.

[0014] Therefore, according to the level of the driving signal, delay processing is only performed in some cases, and no delay processing is performed in other cases, which can achieve low delay in IGBT control and further improve the performance of the IGBT and the ease of adjustability of the IGBT control.

[0015] In some embodiments, the first level for turning on the insulated gate bipolar transistor is a high level, and the second level for turning off the insulated gate bipolar transistor is a low level.

[0016] Therefore, the driving signal is collected according to the high and low levels of the driving signal, and delay processing is performed when the level is high, and no delay processing is performed when the level is low. This can further improve the performance of the IGBT, reduce the cost of the protection circuit, and improve the adjustability of the IGBT control.

[0017] In some embodiments, the detection circuit outputs the second signal at a high level when the voltage is greater than the preset threshold and the bootstrap power supply of the insulated gate bipolar transistor is normal; the detection circuit outputs the second signal at a low level when the voltage is less than or equal to the preset threshold, or the bootstrap power supply of the insulated gate bipolar transistor is turned off, or the bootstrap power supply of the insulated gate bipolar transistor is turned on but abnormal;

[0018] The determination circuit determines that the first signal is valid when the first signal is at a high level; and determines that the second signal is valid when the second signal is at a high level.

[0019] Thus, the second signal indicating the state of the IGBT can be output with a simple configuration, and whether or not the IGBT is abnormal can be determined with a simple configuration.

[0020] In some embodiments, the first level for turning on the insulated gate bipolar transistor is a low level, and the second level for turning off the insulated gate bipolar transistor is a high level.

[0021] Therefore, the driving signal is collected according to the high and low levels of the driving signal, and delay processing is performed at a low level, and no delay processing is performed at a high level. This can further improve the performance of the IGBT, reduce the cost of the protection circuit, and improve the adjustability of the IGBT control.

[0022] In some embodiments, the detection circuit outputs the second signal at a low level when the voltage is greater than the preset threshold and the bootstrap power supply of the insulated gate bipolar transistor is normal; the detection circuit outputs the second signal at a high level when the voltage is less than or equal to the preset threshold, or the bootstrap power supply of the insulated gate bipolar transistor is turned off, or the bootstrap power supply of the insulated gate bipolar transistor is turned on but abnormal;

[0023] The determination circuit determines that the first signal is valid when the first signal is at a low level; and determines that the second signal is valid when the second signal is at a low level.

[0024] Thus, the second signal indicating the state of the IGBT can be output with a simple configuration, and whether or not the IGBT is abnormal can be determined with a simple configuration.

[0025] In some embodiments, a driving power supply of the insulated gate bipolar transistor is different from a detection power supply of the protection device and is safety isolated.

[0026] This allows independent configuration of power supplies for the IGBT and protection circuits, increasing flexibility in product selection.

[0027] In some embodiments, the insulated gate bipolar transistor is configured in an intelligent power module; the intelligent power module includes one or more insulated gate bipolar transistors, and the one or more insulated gate bipolar transistors are respectively configured with the protection device.

[0028] As a result, protection circuits can be configured independently for one or more IGBTs, increasing the flexibility of product selection.

[0029] In some embodiments, the intelligent power module includes an upper bridge circuit, the upper bridge circuit includes three insulated gate bipolar transistors, and the three insulated gate bipolar transistors are respectively configured with the protection device;

[0030] The three insulated gate bipolar transistors respectively have different bootstrap power supplies, and the driving power supplies of the three insulated gate bipolar transistors are different from the detection power supply of the protection device and are safety isolated.

[0031] As a result, not only can a protection circuit be independently configured for the upper bridge circuit, improving the flexibility of product selection; the power supply of the protection circuit and the power supply of the three IGBTs in the upper bridge circuit are also safety-isolated and will not be affected by the common ground of the three drive signals, which can further increase reliability.

[0032] According to another aspect of an embodiment of the present application, a method for protecting an insulated gate bipolar transistor is provided, comprising:

[0033] collecting a driving signal of an insulated gate bipolar transistor, performing delay processing when the driving signal is at a first level for turning on the insulated gate bipolar transistor, or changes from a second level for turning off the insulated gate bipolar transistor to the first level for turning on the insulated gate bipolar transistor, and outputting a first signal according to the signal after the delay processing and the driving signal;

[0034] detecting a voltage between a collector and an emitter of the insulated gate bipolar transistor, and outputting a second signal according to the voltage and a preset threshold; and

[0035] When both the first signal and the second signal are valid, the insulated gate bipolar transistor is determined to be abnormal and an alarm signal or a protection signal is output; when at least one of the first signal and the second signal is invalid, the insulated gate bipolar transistor is determined to be normal.

[0036] One of the beneficial effects of the embodiment of the present application is that: delay processing is performed according to the level of the driving signal of the IGBT and a first signal is output according to the signal after delay processing and the driving signal, and a first signal is output according to the V CE and a preset threshold value to output a second signal, and output an alarm signal or a protection signal when both the first signal and the second signal are valid. It can implement overcurrent protection and / or short-circuit protection by delay processing with a simple structure without affecting the drive signal. In addition, it can also improve the performance of the IGBT and reduce the cost of the protection circuit, and improve the adjustability of the IGBT control.

[0037] With reference to the following description and drawings, specific embodiments of the present application are disclosed in detail, indicating how the principles of the present application can be employed. It should be understood that the embodiments of the present application are not limited in scope. Within the spirit and scope of the appended claims, the embodiments of the present application include many modifications, variations, and equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The included drawings are used to provide a further understanding of the embodiments of the present application, which constitute a part of the specification, are used to illustrate the implementation methods of the present application, and together with the text description, explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without inventive work. In the drawings:

[0039] Figure 1 1 is a schematic diagram of an IGBT protection device according to an embodiment of the present application;

[0040] Figure 2 is a schematic diagram of a protection device, a control device, and an IPM according to an embodiment of the present application;

[0041] Figure 3 This is an example diagram of an IGBT protection device according to an embodiment of the present application;

[0042] Figure 4 is another exemplary diagram of an IGBT protection device according to an embodiment of the present application;

[0043] Figure 5 Schematic diagram of an IGBT protection method according to an embodiment of the present application. DETAILED DESCRIPTION

[0044] The above and other features of the present application will become apparent through the following description with reference to the accompanying drawings. In the specification and the accompanying drawings, specific embodiments of the present application are disclosed in detail, which show some embodiments in which the principles of the present application can be adopted. It should be understood that the present application is not limited to the described embodiments. On the contrary, the present application includes all modifications, variations and equivalents that fall within the scope of the appended claims.

[0045] In the embodiments of the present application, the terms "first", "second", etc. are used to distinguish different elements from the name, but do not indicate the spatial arrangement or temporal order of these elements, and these elements should not be limited by these terms. The term "and / or" includes any one and all combinations of one or more of the associated listed terms. The terms "including", "having", etc. refer to the presence of the stated features, elements, components or components, but do not exclude the presence or addition of one or more other features, elements, components or components.

[0046] In the embodiments of this application, the singular forms "a," "the," etc. may include plural forms and should be broadly understood to mean "a" or "a type" rather than being limited to "one." Furthermore, the term "said" should be understood to include both singular and plural forms, unless the context clearly indicates otherwise. Furthermore, the term "according to" should be understood to mean "at least in part according to...", unless the context clearly indicates otherwise.

[0047] The following describes the implementation of the present application with reference to the accompanying drawings. The IGBT protection device of the embodiment of the present application can be used as a separate product or component in conjunction with the IGBT; it can also be integrated with the IGBT as a single product or component; it can also be integrated into an intelligent power module (IPM) containing an IGBT, but the present application is not limited thereto.

[0048] Embodiments of the first aspect

[0049] An embodiment of the present application provides an IGBT protection device. Figure 1 Schematic diagram of the IGBT protection device according to the embodiment of the present application. Figure 1 As shown, the IGBT protection device 100 includes:

[0050] an acquisition circuit 101 for acquiring a drive signal of the IGBT, performing a delay process when the drive signal is at a first level for turning on the IGBT or changes from a second level for turning off the IGBT to the first level for turning on the IGBT, and outputting a first signal based on the delayed signal and the drive signal;

[0051] The detection circuit 102 detects the voltage between the collector and emitter of the IGBT (V CE ), and output a second signal according to the voltage and a preset threshold; and

[0052] The determination circuit 103 determines that the insulated gate bipolar transistor is abnormal and outputs an alarm signal or a protection signal when both the first signal and the second signal are valid, and determines that the insulated gate bipolar transistor is normal when at least one of the first signal and the second signal is invalid.

[0053] In some embodiments, the driving signal of the IGBT can be, for example, a pulse width modulation (PWM) signal, which turns on (ON) the IGBT when the PWM signal is at a high level and turns off (OFF) the IGBT when the PWM signal is at a low level; however, the present application is not limited to this, and for example, it can also be other driving signals.

[0054] In some embodiments, the driving signal of the IGBT can be output from a control device, such as a central processing unit (CPU) or a field-programmable gate array (FPGA), to an intelligent power module (IPM) including the IGBT, but the present application is not limited thereto.

[0055] Figure 2 FIG. 1 is a schematic diagram of a protection device, a control device and an IPM according to an embodiment of the present application. Figure 2 As shown, the CPU / FPGA 201 can output a PWM signal, which can control the IGBT in the IPM 202. Figure 2 As shown, the IGBT protection device 100 can collect the PWM signal. For example, when the PWM signal is at a high level or changes from a low level to a high level, a delay process is performed, and the delayed signal and the PWM signal are ANDed to generate a first signal.

[0056] like Figure 2 As shown, the IGBT protection device 100 can also control the voltage V of the IGBT in the IPM 202. CE For example, in the V CE When the voltage is greater than the preset threshold and the IGBT bootstrap power supply is normal, it outputs a high level; CE When the voltage is less than or equal to the preset threshold, or the bootstrap power supply of the IGBT is turned off, or the bootstrap power supply of the IGBT is turned on but abnormal, a low level is output to generate a second signal.

[0057] For example, the IGBT protection device 100 may determine that a high-level first signal and a high-level second signal are valid. If both the first signal and the second signal are valid, the IGBT protection device 100 determines that the IGBT in the IPM 202 is operating abnormally, and may thereby output an alarm signal or a protection signal to the CPU / FPGA 201, or may directly output an alarm signal or a protection signal to the IPM 202. If the first signal and / or the second signal are invalid, the IGBT protection device 100 determines that the IGBT in the IPM 202 is operating normally and does not output an alarm signal or a protection signal.

[0058] In the embodiments of the present application, abnormal IGBT operation can be understood as potentially damaging or destructive to the IGBT, including, for example, overcurrent and / or short circuit conditions. Conditions such as the IGBT's bootstrap power supply being turned off, or the bootstrap power supply being turned on but abnormal (e.g., undervoltage), can be detected and protected in other circuits or components. In the embodiments of the present application, these conditions do not damage or destruct the IGBT and are therefore considered normal.

[0059] like Figure 2 As shown, the PWM signal can also be processed, isolated, etc. (optionally); this structure can be applied to a servo drive; Figure 2 The structure shown can also be applied to frequency converters, inverters, etc. The present application is not limited thereto, and the protection device of the present application embodiment can be considered for use in any scenario where IGBT is applied.

[0060] In the embodiment of the present application, a delay process is performed according to the level of the driving signal of the IGBT, and a first signal is output according to the signal after the delay process and the driving signal, and a first signal is output according to the V CE and a preset threshold value to output a second signal, and output an alarm signal or a protection signal when both the first signal and the second signal are valid. It can implement overcurrent protection and / or short-circuit protection by delay processing with a simple structure without affecting the drive signal. In addition, it can also improve the performance of the IGBT and reduce the cost of the protection circuit, and improve the adjustability of the IGBT control.

[0061] In some embodiments, the acquisition circuit 101 does not perform delay processing when the driving signal is at the second level for turning off the IGBT, or changes from the first level for turning on the IGBT to the second level for turning off the IGBT.

[0062] Therefore, according to the level of the driving signal, delay processing is only performed in some cases, and no delay processing is performed in other cases, so that low delay of IGBT control can be achieved and the adjustability of IGBT control can be further improved.

[0063] In some embodiments, the first level for turning on the IGBT is a high level, and the second level for turning off the insulated gate bipolar transistor is a low level.

[0064] Therefore, the driving signal is collected according to the high and low levels of the driving signal, and delay processing is performed when the level is high, and no delay processing is performed when the level is low. This can further improve the performance of the IGBT, reduce the cost of the protection circuit, and improve the adjustability of the IGBT control.

[0065] In some embodiments, the detection circuit 102 outputs the second signal at a high level when the voltage is greater than the preset threshold and the bootstrap power supply of the IGBT is normal; the detection circuit 102 outputs the second signal at a low level when the voltage is less than or equal to the preset threshold, or the bootstrap power supply of the IGBT is turned off, or the bootstrap power supply of the IGBT is turned on but abnormal.

[0066] The determination circuit 103 determines that the first signal is valid when the first signal is at a high level; and determines that the second signal is valid when the second signal is at a high level.

[0067] Thus, the second signal indicating the state of the IGBT can be output with a simple configuration, and whether or not the IGBT is abnormal can be determined with a simple configuration.

[0068] It should be noted that the first level and the second level are not limited thereto. For example, the first level may be a low level and the second level may be a high level, and processing may be performed accordingly.

[0069] In some embodiments, the first level for turning on the IGBT is a low level, and the second level for turning off the insulated gate bipolar transistor is a high level.

[0070] Therefore, the driving signal is collected according to the high and low levels of the driving signal, and delay processing is performed at a low level, and no delay processing is performed at a high level. This can further improve the performance of the IGBT, reduce the cost of the protection circuit, and improve the adjustability of the IGBT control.

[0071] In some embodiments, the detection circuit 102 outputs the second signal at a low level when the voltage is greater than the preset threshold and the bootstrap power supply of the IGBT is normal; the detection circuit 102 outputs the second signal at a high level when the voltage is less than or equal to the preset threshold, or the bootstrap power supply of the IGBT is turned off, or the bootstrap power supply of the IGBT is turned on but abnormal.

[0072] The determination circuit 103 determines that the first signal is valid when the first signal is at a low level; and determines that the second signal is valid when the second signal is at a low level.

[0073] Thus, the second signal indicating the state of the IGBT can be output with a simple configuration, and whether or not the IGBT is abnormal can be determined with a simple configuration.

[0074] For convenience, the following description takes the case where the first level is a high level and the second level is a low level as an example to exemplify the protection device of the embodiment of the present application through a circuit.

[0075] Figure 3 FIG. 1 is an example diagram of an IGBT protection device according to an embodiment of the present application. Figure 3 As shown, the protection device 300 includes an acquisition circuit 301 , a detection circuit 302 and a determination circuit 303 .

[0076] For the acquisition circuit 301, as Figure 3 As shown, the PWM signal can be delayed through branch 3011 , and the delayed signal is input to one input end of the AND gate 3013 ; the PWM signal is input to the other input end of the AND gate 3013 through branch 3012 .

[0077] For example, when the PWM signal is at a high level (H), or changes from a low level (L) to a high level (H), the PWM signal is delayed by components such as capacitors in the acquisition circuit 301. The delay time can be determined by the values ​​of resistors and capacitors, for example, such that the delay time is less than the maximum withstand time of the IGBT and greater than the IGBT turn-on time plus the software processing time. By adjusting the values ​​of components such as resistors and capacitors, the delay time can be adjusted, thereby improving adjustability.

[0078] like Figure 3 As shown, when the PWM signal is at a low level (L), or when it transitions from a high level (H) to a low level (L), the delay processing of branch 3011 is canceled due to the AND gate processing with the original collected drive signal of branch 3012. In other words, no delay is performed. This can reduce the delay and improve the performance of the IGBT.

[0079] For the detection circuit 302, as Figure 3 As shown, the IGBT bootstrap power supply (e.g. Figure 3 The detection power supply V B Related) is turned on and working properly, and V CE is greater than a preset threshold (e.g. by detecting the power supply V BIn the case of determination), a signal is generated at A through the detection circuit 302, and the second signal is made high level through the optical coupler 3021; CE When the value is less than or equal to the preset threshold, or the bootstrap power supply of the IGBT is turned off, or the bootstrap power supply of the IGBT is turned on but abnormal, no signal is generated at A through the detection circuit 302, and the second signal is made low level through the optical coupler 3021.

[0080] For the determination circuit 303, as Figure 3 As shown, the first signal is input to one input terminal of the AND gate 3031 ; the second signal is input to the other input terminal of the AND gate 3031 .

[0081] For example, if the first signal is at a high level, the first signal is valid; if the second signal is at a high level, the second signal is valid. When both the first signal and the second signal are at a high level, the determination circuit 303 outputs a high level and determines that the IGBT is abnormal. This high level is output as an alarm signal or a protection signal. When the first signal and / or the second signal are at a low level, the determination circuit 303 outputs a low level and determines that the IGBT is normal.

[0082] The above attached Figure 3 The embodiments of the present application are merely illustrative, but the present application is not limited thereto. Specific components may be adjusted as needed. For example, the acquisition circuit 301 uses only the AND gate 3013 as an example to schematically illustrate the first signal, but the present application is not limited thereto. For example, other components, parts, or circuits may be used to implement the same or similar functions.

[0083] In some embodiments, the driving power supply of the IGBT (eg Figure 3 The power supply V N ) is different from the detection power supply of the protection device (for example Figure 3 The power supply V B ) and are isolated by safety regulations. For example, Figure 3 As shown, V B and V N They are configured separately and are safety isolated from each other.

[0084] This allows independent configuration of power supplies for the IGBT and protection circuits, increasing flexibility in product selection.

[0085] In some embodiments, the IGBT is configured in an IPM; the IPM includes one or more IGBTs, and the one or more IGBTs are respectively configured with the protection device.

[0086] As a result, protection circuits can be configured independently for one or more IGBTs, increasing the flexibility of product selection.

[0087] In some embodiments, the IPM includes an upper bridge circuit, the upper bridge circuit includes three IGBTs, and the three IGBTs are respectively configured with the protection device; the three IGBTs have different bootstrap power supplies, and the driving power supplies of the three IGBTs are different from the detection power supply of the protection device and are safety isolated.

[0088] Figure 4 FIG. 1 is another example diagram of the IGBT protection device according to an embodiment of the present application. Figure 4 As shown in FIG, protection devices can be configured for the three phases U, V, and W respectively. And the driving power supplies of the three IGBTs corresponding to the three phases U, V, and W (such as Figure 4 V N As shown) and the detection power supply of the protection device (as Figure 4 V B (U), V B (V), V B (W) A total of four power supplies are configured separately and are safety-isolated from each other.

[0089] like Figure 4 As shown, the output signals of the protection devices respectively configured for the U, V, and W phases can be input into transistor 401. Through transistor 401, a comprehensive judgment can be made on the overcurrent protection and / or short-circuit protection of the three IGBTs in the upper bridge circuit, and an alarm signal or protection signal can be output when any output signal (e.g., indicating a valid high level) is present, thereby further improving the reliability of circuit protection.

[0090] As a result, not only can the protection circuit be independently configured for the upper bridge circuit, improving the flexibility of product selection; the detection power supply of the protection circuit and the drive power supply of the three IGBTs in the upper bridge circuit are also safety-isolated, and will not be affected by the common ground of the three drive signals, which can further increase reliability.

[0091] It is worth noting that Figures 1 to 4 The embodiments of the present application are only schematically described, but the present application is not limited thereto; for example, other components or devices may also be provided, and the details may be referred to the relevant technology, and the description is omitted here. Figures 1 to 4 For components or elements not specifically specified, reference may be made to the relevant technology, and this application does not limit this.

[0092] In addition, the above is only an exemplary description of each device or component, but the present application is not limited thereto, and the specific content of each device or component can also refer to the relevant technology; in addition, Figures 1 to 4 Devices or components not shown, or reduced Figures 1 to 4 One or more devices or components.

[0093] As can be seen from the above embodiment, the delay processing is performed according to the level of the driving signal of the IGBT and the first signal is output according to the signal after the delay processing and the driving signal. CE and a preset threshold value to output a second signal, and output an alarm signal or a protection signal when both the first signal and the second signal are valid; it can implement overcurrent protection and / or short-circuit protection by delay processing with a simple structure without affecting the drive signal, and can also improve the performance of the IGBT and reduce the cost of the protection circuit, and improve the adjustability of the IGBT control.

[0094] Embodiments of the second aspect

[0095] The embodiment of the present application also provides an IGBT protection method, and the contents that are the same as those in the embodiment of the first aspect will not be repeated.

[0096] Figure 5 FIG. 1 is a schematic diagram of an IGBT protection method according to an embodiment of the present application. Figure 5 As shown, the method includes:

[0097] Step 501: Acquire a driving signal of the IGBT, perform delay processing when the driving signal is at a first level for turning on the IGBT, or changes from a second level for turning off the IGBT to the first level for turning on the IGBT, and output a first signal based on the delayed signal and the driving signal.

[0098] Step 502 , detecting a voltage between a collector and an emitter of the IGBT, and outputting a second signal according to the voltage and a preset threshold; and

[0099] Step 503 : When both the first signal and the second signal are valid, determine that the IGBT is abnormal and output an alarm signal or a protection signal; when at least one of the first signal and the second signal is invalid, determine that the IGBT is normal.

[0100] It is worth noting that the above Figure 5 The embodiments of the present application are only schematically described, but the present application is not limited thereto. For example, the execution order of each step can be appropriately adjusted, and other steps can be added or some steps can be reduced. Those skilled in the art can make appropriate modifications based on the above content, and are not limited to the above appended drawings. Figure 5 Records of.

[0101] The embodiment of the present application also provides an IPM, and the contents that are the same as those in the embodiment of the first aspect are not repeated here.

[0102] The IPM of the embodiment of the present application includes one or more IGBTs, and the IPM also includes the protection device 100 as described in the embodiment of the first aspect. For example, the one or more protection devices 100 described in the embodiment of the first aspect can be integrated into the IPM.

[0103] In some embodiments, the IPM includes an upper bridge circuit, the upper bridge circuit includes three IGBTs, and the three IGBTs are respectively configured with the protection device; the three IGBTs have different bootstrap power supplies, the driving power supplies of the three IGBTs are different from the detection power supply of the protection device and are safety isolated.

[0104] In some embodiments, the output signals of the protection devices configured for the three IGBTs in the upper bridge circuit can be input into a transistor. Through the transistor, a comprehensive judgment can be made on the overcurrent protection and / or short-circuit protection of the three IGBTs in the upper bridge circuit. When any output signal (e.g., indicating a valid high level) is present, an alarm signal or protection signal is output, thereby further improving the reliability of circuit protection.

[0105] The present application has been described above in conjunction with specific embodiments. However, those skilled in the art should understand that these descriptions are merely illustrative and are not intended to limit the scope of protection of the present application. Those skilled in the art may make various modifications and variations to the present application based on the spirit and principles of the present application, and such modifications and variations are also within the scope of the present application.

[0106] The preferred embodiments of the present application have been described above with reference to the accompanying drawings. Many features and advantages of these embodiments are apparent from this detailed description, and the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Furthermore, since numerous modifications and variations will readily occur to those skilled in the art, the embodiments of the present application are not intended to be limited to the precise structure and operation illustrated and described, but are intended to cover all suitable modifications, variations, and equivalents that fall within the scope thereof.

Claims

1. A protection device for an insulated gate bipolar transistor, characterized in that: The protection device comprises: an acquisition circuit that acquires a drive signal of the insulated gate bipolar transistor, performs delay processing when the drive signal is at a first level for turning on the insulated gate bipolar transistor, or changes from a second level for turning off the insulated gate bipolar transistor to the first level for turning on the insulated gate bipolar transistor, and outputs a first signal based on the signal after the delay processing and the drive signal; a detection circuit configured to detect a voltage between a collector and an emitter of the insulated gate bipolar transistor and output a second signal according to the voltage and a preset threshold; and a determination circuit that determines that the insulated gate bipolar transistor is abnormal and outputs an alarm signal or a protection signal when both the first signal and the second signal are valid, and determines that the insulated gate bipolar transistor is normal when at least one of the first signal and the second signal is invalid, The acquisition circuit does not perform the delay processing when the driving signal is at the second level for turning off the insulated gate bipolar transistor, or changes from the first level for turning on the insulated gate bipolar transistor to the second level for turning off the insulated gate bipolar transistor.

2. The protection device according to claim 1, wherein: The first level for turning on the insulated gate bipolar transistor is a high level, and the second level for turning off the insulated gate bipolar transistor is a low level.

3. The protection device according to claim 2, wherein: The detection circuit outputs the second signal of a high level when the voltage is greater than the preset threshold and the bootstrap power supply of the insulated gate bipolar transistor is normal; the detection circuit outputs the second signal of a low level when the voltage is less than or equal to the preset threshold, or the bootstrap power supply of the insulated gate bipolar transistor is turned off, or the bootstrap power supply of the insulated gate bipolar transistor is turned on but abnormal; The determination circuit determines that the first signal is valid when the first signal is at a high level; and determines that the second signal is valid when the second signal is at a high level.

4. The protection device according to claim 1, wherein: The first level for turning on the insulated gate bipolar transistor is a low level, and the second level for turning off the insulated gate bipolar transistor is a high level.

5. The protection device according to claim 4, wherein: The detection circuit outputs the second signal of a low level when the voltage is greater than the preset threshold and the bootstrap power supply of the insulated gate bipolar transistor is normal; the detection circuit outputs the second signal of a high level when the voltage is less than or equal to the preset threshold, or the bootstrap power supply of the insulated gate bipolar transistor is turned off, or the bootstrap power supply of the insulated gate bipolar transistor is turned on but abnormal; The determination circuit determines that the first signal is valid when the first signal is at a low level; and determines that the second signal is valid when the second signal is at a low level.

6. The protection device according to claim 1, wherein: The driving power supply of the insulated gate bipolar transistor is different from the detection power supply of the protection device and is safety isolated.

7. The protection device according to any one of claims 1 to 6, wherein: The insulated gate bipolar transistor is configured in an intelligent power module; the intelligent power module includes one or more insulated gate bipolar transistors, and the one or more insulated gate bipolar transistors are respectively configured with the protection device.

8. The protection device according to claim 7, wherein: The intelligent power module includes an upper bridge circuit, the upper bridge circuit includes three insulated gate bipolar transistors, and the three insulated gate bipolar transistors are respectively configured with the protection device; The three insulated gate bipolar transistors respectively have different bootstrap power supplies. The driving power supplies of the three insulated gate bipolar transistors are different from the detection power supply of the protection device and are safety isolated.

9. A method for protecting an insulated gate bipolar transistor, characterized in that: The protection method includes: collecting a driving signal of an insulated gate bipolar transistor, performing delay processing when the driving signal is at a first level for turning on the insulated gate bipolar transistor, or changes from a second level for turning off the insulated gate bipolar transistor to the first level for turning on the insulated gate bipolar transistor, and outputting a first signal according to the signal after the delay processing and the driving signal; detecting a voltage between a collector and an emitter of the insulated gate bipolar transistor, and outputting a second signal according to the voltage and a preset threshold; and When both the first signal and the second signal are valid, the insulated gate bipolar transistor is determined to be abnormal and an alarm signal or a protection signal is output; when at least one of the first signal and the second signal is invalid, the insulated gate bipolar transistor is determined to be normal. The delay process is not performed when the driving signal is at the second level for turning off the insulated gate bipolar transistor, or changes from the first level for turning on the insulated gate bipolar transistor to the second level for turning off the insulated gate bipolar transistor.

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