IGBT module protection device, IGBT module and inverter

Abstract

The present invention provides an IGBT module protection device, an IGBT module and a frequency converter, the device comprising: a first and a second current detection device, an action device, a magnetic device and a spare diode; the first and the second current detection device and the magnetic device are connected in series to form a loop, and the loop is disconnected when the IGBT module is working normally; the spare diode is connected in parallel with the IGBT module freewheeling diode; the first current detection device is used to detect whether there is current between the G pole of the IGBT module and the drive circuit, and the second current detection device is used to detect whether there is current in the module freewheeling diode loop, and when the first and the second current detection devices both detect current, the magnetic device is powered on to generate a magnetic field to attract the action device to operate, disconnect the freewheeling diode of the IGBT module itself, and connect the spare diode. When the module freewheeling diode is broken down and short-circuited, the protection device is used to replace it in time with the spare circuit to ensure that the system operates normally without interruption.

Description

Technical Field

[0001] The present invention relates to the technical field of power electronics, and in particular to an IGBT module protection device, an IGBT module and a frequency converter. Background Art

[0002] IGBT, a fully controlled device, occupies a leading position in medium and high power electronic equipment with its excellent performance and modular design. Among them, the protection of IGBT modules focuses more on the protection of IGBT chips, while the freewheeling diode of IGBT modules lacks protection. When the diode is damaged, there is a risk of burning the module. Summary of the invention

[0003] When the freewheeling diode of the IGBT module is damaged, in order to protect the IGBT module and make it work normally, an embodiment of the present invention provides an IGBT module protection device, the device comprising: a first current detection device, a second current detection device, an action device, a magnetic device and a backup diode;

[0004] The first current detection device, the second current detection device and the magnetic device are connected in series to form a loop, and the loop is disconnected when the IGBT module is working normally; the backup diode is connected in parallel with the freewheeling diode of the IGBT module itself; the first current detection device is used to detect whether there is current between the G pole of the IGBT module and the drive circuit, and the second current detection device is used to detect whether there is current in the freewheeling diode circuit of the IGBT module. When the first current detection device and the second current detection device both detect current, the magnetic device is energized to generate a magnetic field to attract the action device, disconnect the freewheeling diode of the IGBT module itself, and connect the backup diode.

[0005] In one embodiment, the actuating device includes two switches, which are respectively connected in series in the freewheeling diode circuit and the backup diode circuit of the IGBT module itself.

[0006] In one embodiment, when the IGBT module is operating normally, the switch connected in series in the freewheeling diode loop of the IGBT module itself is in a closed state.

[0007] In one embodiment, when the IGBT module operates normally, the switch connected in series in the backup diode loop is in an open state.

[0008] In one embodiment, the magnetic device comprises a magnetic coil.

[0009] In one embodiment, the protection device further includes: an alarm device, which is used to generate alarm information when the first current detection device and the second current detection device both detect current.

[0010] In one embodiment, the alarm device includes an audible and visual alarm device.

[0011] In one embodiment, the backup diode is of the same type as the freewheeling diode of the IGBT module itself.

[0012] On the one hand, an embodiment of the present invention further provides an IGBT module with a protection device, the IGBT module comprising: an IGBT chip, a drive circuit, a freewheeling diode and the protection device as claimed in the claims;

[0013] The first current detection device, the second current detection device and the magnetic device of the protection device are connected in series to form a loop, and the loop is disconnected when the IGBT module is working normally; the backup diode of the protection device is connected in parallel with the freewheeling diode; the first current detection device is used to detect whether there is current between the G pole of the IGBT module and the drive circuit, and the second current detection device is used to detect whether there is current in the freewheeling diode circuit of the IGBT module. When the first current detection device and the second current detection device both detect current, the magnetic device is energized to generate a magnetic field to attract the action device, disconnect the freewheeling diode of the IGBT module itself, and connect the backup diode.

[0014] On the other hand, an embodiment of the present invention further provides a frequency converter, the frequency converter comprising the IGBT module with the protection device, the IGBT module being used for rectification and / or inversion.

[0015] The embodiment of the present invention can protect the IGBT chip circuit through the driving circuit and the freewheeling diode circuit of the IGBT module by relying on the action device circuit when an abnormality occurs in the IGBT module, thereby ensuring that the system can operate normally without interruption. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A schematic diagram of an IGBT module circuit with a protection device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Figure 1 The schematic diagram of an IGBT module circuit with a protection device provided by an embodiment of the present invention is shown in FIG. Figure 1 As shown, the device mainly includes: a first current detection device 1, a second current detection device 2, an action device 3, a magnetic device 4 and a backup diode 5.

[0020] Among them, the first current detection device 1, the second current detection device 2 and the magnetic device 3 are connected in series to form a loop. When the IGBT module is working normally, the loop is disconnected. The backup diode 5 is connected in parallel with the freewheeling diode 6 of the IGBT module itself. The first current detection device 1 is used to detect whether there is current between the G pole of the IGBT module and the drive circuit, and the second current detection device 2 is used to detect whether there is current in the freewheeling diode circuit of the IGBT module. When the first current detection device 1 and the second current detection device 2 both detect current, the switch in the detection device is closed, otherwise the switch is disconnected. When both current detection devices detect current, the loop is closed and turned on, the magnetic device 4 is energized, and the magnetic field is generated to attract the action device 3 to act, disconnecting the freewheeling diode 6 of the IGBT module itself and connecting the backup diode 5.

[0021] The embodiment of the present invention determines whether there is current passing through the magnetic device by placing a current detection device between the G pole of the IGBT module and the drive circuit, and in the freewheeling diode loop of the IGBT module. Whether there is current passing through the magnetic device determines the switch state of the action device, and then switches the access mode of the circuit. When the freewheeling diode 6 is broken down and short-circuited, the two current detections are used for judgment, and then the action device 3 is relied on to promptly handle and resolve the current abnormality, and switch to the backup circuit to ensure that the system can operate normally without interruption.

[0022] In one embodiment, the action device 3 includes two switches ① and ②, wherein the switch ① is connected in series in the freewheeling diode circuit of the IGBT module itself, and the switch ② is connected in series in the standby diode circuit to control the on and off of the respective diode circuits.

[0023] In one embodiment, when the IGBT module operates normally, the switch ① connected in series in the freewheeling diode loop of the IGBT module itself is in a closed state.

[0024] In one embodiment, when the IGBT module operates normally, the switch ② connected in series in the backup diode loop is in an off state.

[0025] When the IGBT module is working normally, in an ideal state, when there is current flowing between the G pole and the drive circuit, there is no current flowing through the module freewheeling diode circuit, and the freewheeling diode 6 is in a cut-off state; and when there is no current flowing between the G pole and the drive circuit, the freewheeling diode 6 is in a conducting state. At this time, because the first current detection device 1 and the second current detection device 2 cannot be closed at the same time, there is no current flowing through the magnetic device 4, and the action device 3 is in a default state, that is, switch ① is closed, switch ② is open, and the entire IGBT module is working normally.

[0026] When the freewheeling diode 6 of the IGBT module is broken down and damaged, since both the first current detection device 1 and the second current detection device 2 can detect that there is current passing between the G pole and the drive circuit and the module freewheeling diode circuit, the switches in the two detection devices are closed at the same time, the circuit is turned on, and the magnetic device 4 is energized to generate a magnetic field to attract the action device to turn to switch ② (once the switch is switched, it cannot automatically return, that is, it is fixed at the corresponding switch terminal), and the spare diode 5 is connected at this time. After the spare diode 5 is connected, the IGBT module resumes normal operation, that is, when there is current passing between the G pole and the drive circuit, there is no current passing through the module freewheeling diode circuit, and the spare diode 5 is in the cut-off state. When there is current passing between the G pole and the drive circuit, the spare diode 5 is in the on state, and at this time the first current detection device 1 and the second current detection device 2 are alternately closed again, the magnetic device 4 is no longer energized, the IGBT module continues to work normally, and the system can also operate normally.

[0027] In one embodiment, the magnetic device 4 includes a magnetic coil, which generates a magnetic field by energizing the magnetic coil to attract the action device 3 to operate.

[0028] In one embodiment, the above-mentioned protection device also includes an alarm device (not shown in the figure). When the first current detection device 1 and the second current detection device 2 both detect current, the alarm device is used to generate an alarm message to notify and remind the IGBT module of a fault, so as to facilitate timely maintenance by the staff.

[0029] In one embodiment, the above-mentioned alarm device includes an audible and visual alarm device, that is, it reminds the staff through audible and visual alarms.

[0030] In one embodiment, the backup diode 5 is of the same type as the freewheeling diode 6 of the IGBT module itself.

[0031] In addition, the embodiment of the present invention also provides an IGBT module with a protection device, the IGBT module comprising: an IGBT chip, a drive circuit, a freewheeling diode and Figure 1 The protection device shown in . The first current detection device 1, the second current detection device 2 and the magnetic device 3 of the protection device are connected in series to form a loop, and the loop is disconnected when the IGBT module is working normally. The backup diode 5 and the freewheeling diode 6 of the protection device are connected in parallel. The first current detection device 1 is used to detect whether there is current between the G pole of the IGBT module and the drive circuit, and the second current detection device 2 is used to detect whether there is current in the freewheeling diode circuit of the IGBT module. When the first current detection device 1 and the second current detection device 2 both detect current, the magnetic device 4 is energized to generate a magnetic field to attract the action device 3 to act, disconnect the freewheeling diode 6 of the IGBT module itself, and connect the backup diode 5.

[0032] In addition, an embodiment of the present invention further provides a frequency converter, characterized in that the frequency converter comprises the above-mentioned IGBT module with a protection device, wherein the IGBT module is used for rectification and / or inversion.

[0033] The present invention uses specific embodiments to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. An IGBT module protection device, characterized in that: The device comprises: a first current detection device, a second current detection device, an action device, a magnetic device and a backup diode; The first current detection device, the second current detection device and the magnetic device are connected in series to form a loop, and the loop is disconnected when the IGBT module is working normally; the backup diode is connected in parallel with the freewheeling diode of the IGBT module itself; the first current detection device is used to detect whether there is current between the G pole of the IGBT module and the drive circuit, and the second current detection device is used to detect whether there is current in the freewheeling diode circuit of the IGBT module. When the first current detection device and the second current detection device both detect current, the magnetic device is energized to generate a magnetic field to attract the action device, disconnect the freewheeling diode of the IGBT module itself, and connect the backup diode.

2. The IGBT module protection device according to claim 1, characterized in that: The action device comprises two switches which are respectively connected in series in the freewheeling diode circuit and the standby diode circuit of the IGBT module itself.

3. The IGBT module protection device according to claim 2, characterized in that: When the IGBT module is operating normally, the switch connected in series in the freewheeling diode loop of the IGBT module itself is in a closed state.

4. The IGBT module protection device according to claim 2, characterized in that: When the IGBT module operates normally, the switch connected in series in the backup diode loop is in an off state.

5. The IGBT module protection device according to claim 1, characterized in that: The magnetic device includes a magnetic coil.

6. The IGBT module protection device according to claim 1, characterized in that: The protection device further includes: an alarm device, which is used to generate alarm information when the first current detection device and the second current detection device both detect current.

7. The IGBT module protection device according to claim 6, characterized in that: The alarm device includes an audible and visual alarm device.

8. The IGBT module protection device according to claim 1, characterized in that: The backup diode is of the same model as the freewheeling diode of the IGBT module itself.

9. An IGBT module with a protection device, characterized in that: The IGBT module comprises: an IGBT chip, a drive circuit, a freewheeling diode and a protection device according to any one of claims 1 to 8; The first current detection device, the second current detection device and the magnetic device of the protection device are connected in series to form a loop, and the loop is disconnected when the IGBT module is working normally; the backup diode of the protection device is connected in parallel with the freewheeling diode; the first current detection device is used to detect whether there is current between the G pole of the IGBT module and the drive circuit, and the second current detection device is used to detect whether there is current in the freewheeling diode circuit of the IGBT module. When the first current detection device and the second current detection device both detect current, the magnetic device is energized to generate a magnetic field to attract the action device, disconnect the freewheeling diode of the IGBT module itself, and connect the backup diode.

10. A frequency converter, characterized in that: The frequency converter comprises the IGBT module with protection device according to claim 9, and the IGBT module is used for rectification and / or inversion.

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