Driving protection circuit, device and system

Abstract

The invention discloses a driving protection circuit, device and system, and relates to the technical field of protection circuits, the driving protection circuit comprises a driving chip and a charging circuit, a first output pin of the driving chip is used for being connected with a first end of a power semiconductor device, and a second output pin of the driving chip is used for being connected with a second end of the power semiconductor device; the second output pin of the driving chip is used for being connected with the second end of the power semiconductor device, the charging circuit is arranged between the first output pin of the driving chip and the protection unit, when the power semiconductor device is short-circuited, the protection unit is disconnected, and the charging circuit enables the voltage of the first output pin of the driving chip to be increased to a preset value; the second output pin of the driving chip outputs a turn-off signal to the second end of the power semiconductor device, the blanking time of the protection circuit is shortened through the charging circuit, the soft turn-off speed of the protection circuit is improved, and the problem that the power semiconductor device is damaged due to overcurrent under the short-circuit working condition is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of protection circuits, and in particular to a driving protection circuit, device and system. Background Art

[0002] The desaturation protection circuit is a protection circuit for power semiconductor devices. Its core function is to quickly trigger the protection mechanism by detecting the abnormal increase in the collector-emitter voltage of the power semiconductor device when the device is short-circuited or overloaded, thereby preventing the device from being damaged by overheating or overcurrent. It can quickly take protective measures when the device is short-circuited or overloaded to ensure the safety and reliability of the system.

[0003] The protection circuit in the prior art has a long blanking time and a slow soft shutdown speed, which causes the power semiconductor device to withstand energy exceeding the tolerance limit under short-circuit conditions, and the device is easily damaged by overcurrent. Summary of the Invention

[0004] Embodiments of the present invention provide a driving protection circuit, device, and system to solve the technical problems in the related art that the existing protection circuit has a long blanking time and a slow soft shutdown speed, which causes the power semiconductor device to withstand energy exceeding the tolerance limit under short-circuit conditions and the device is easily damaged by overcurrent.

[0005] In a first aspect, a drive protection circuit is provided, comprising: A driver chip, wherein a first output pin of the driver chip is used to connect to a first end of a power semiconductor device, and a second output pin of the driver chip is used to connect to a second end of the power semiconductor device; a charging circuit, the charging circuit being provided between the first output pin of the driver chip and the protection unit; When the power semiconductor device is short-circuited, the protection unit is disconnected, the charging circuit increases the voltage of the first output pin of the driver chip to a preset value, and the second output pin of the driver chip outputs a shutdown signal to the second end of the power semiconductor device.

[0006] In some embodiments, the charging circuit includes: power supply; a first resistor, wherein a first end of the first resistor is connected to the power supply, and a second end of the first resistor is connected to a first output pin of the driver chip; A capacitor, wherein a first end of the capacitor is connected to the second end of the first resistor and the first output pin of the driver chip, and a second end of the capacitor is grounded.

[0007] In some embodiments, the capacitor is an electrolytic capacitor.

[0008] In some embodiments, the protection unit includes: a second resistor, wherein a first end of the second resistor is connected to the second end of the first resistor and the first output pin of the driver chip; A first diode, wherein an anode of the first diode is connected to the second end of the second resistor, and a cathode of the first diode is connected to the first end of the power semiconductor device.

[0009] In some embodiments, the protection unit further includes: A second diode, wherein an anode of the second diode is connected to a cathode of the first diode, and a cathode of the second diode is connected to a first end of the power semiconductor device.

[0010] In some embodiments, the driving protection circuit further includes: a third resistor, wherein a first end of the third resistor is connected to the third output pin of the driver chip, and a second end of the third resistor is connected to the second output pin of the driver chip and the second end of the power semiconductor device; A transistor, wherein the base of the transistor is connected to the first end of the third resistor, the emitter of the transistor is connected to the second end of the third resistor, the second output pin of the driver chip, and the second end of the power semiconductor device, and the collector of the transistor is grounded.

[0011] In some embodiments, the driving protection circuit further includes: a fourth resistor, wherein a first end of the fourth resistor is connected to the second output pin of the driver chip, and a second end of the fourth resistor is connected to the second end of the power semiconductor device.

[0012] In some embodiments, the power semiconductor device is an insulated gate bipolar transistor or a metal oxide semiconductor field effect transistor.

[0013] In a second aspect, a drive protection device is provided, comprising the aforementioned drive protection circuit.

[0014] In a third aspect, a drive protection system is provided, comprising the aforementioned drive protection device.

[0015] The beneficial effects brought about by the technical solution provided by the present invention include: An embodiment of the present invention provides a driving protection circuit, device and system, wherein the driving protection circuit includes: a driving chip and a charging circuit, wherein a first output pin of the driving chip is used to connect to a first end of a power semiconductor device, and a second output pin of the driving chip is used to connect to a second end of the power semiconductor device, and the charging circuit is arranged between the first output pin of the driving chip and a protection unit. When a short circuit occurs in the power semiconductor device, the protection unit is disconnected, and the charging circuit increases the voltage of the first output pin of the driving chip to a preset value, and the second output pin of the driving chip outputs a shutdown signal to the second end of the power semiconductor device. The charging speed of the protection circuit is accelerated by the charging circuit, and the blanking time of the protection circuit is shortened. The driving chip can quickly output a shutdown signal to shut down the power semiconductor device when the voltage rises to a preset value, thereby improving the soft shutdown speed of the protection circuit and avoiding the problem of overcurrent damage to the power semiconductor device under short-circuit conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. 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 creative work.

[0017] Figure 1 A block diagram of a drive protection circuit provided by an embodiment of the present invention; Figure 2 A schematic diagram of a driving protection circuit provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 making creative efforts shall fall within the scope of protection of the present invention.

[0019] An embodiment of the present invention provides a driving protection circuit, which can solve the technical problems in the related art that the existing protection circuit has a long blanking time and a slow soft shutdown speed, resulting in the power semiconductor device being subjected to energy exceeding the tolerance limit under short-circuit conditions and the device being easily damaged by overcurrent.

[0020] Figure 1A driving protection circuit provided by an embodiment of the present invention includes: a driving chip and a charging circuit, wherein the first output pin of the driving chip is used to connect to the first end of a power semiconductor device, and the second output pin of the driving chip is used to connect to the second end of the power semiconductor device. The charging circuit is arranged between the first output pin of the driving chip and a protection unit. When the power semiconductor device is short-circuited, the protection unit is disconnected, the charging circuit increases the voltage of the first output pin of the driving chip to a preset value, and the second output pin of the driving chip outputs a shutdown signal to the second end of the power semiconductor device.

[0021] A driver protection circuit provided in an embodiment of the present invention includes a driver chip and a charging circuit. A first output pin of the driver chip is configured to be connected to a first end of a power semiconductor device, and a second output pin of the driver chip is configured to be connected to a second end of the power semiconductor device. When the power semiconductor device is an IGBT, the first output pin DESAT of the driver chip is connected to the collector of the power semiconductor device, and the second output pin OUT of the driver chip is connected to the gate of the power semiconductor device. The charging circuit is provided between the first output pin DESAT of the driver chip and a protection unit. When a short circuit occurs in the power semiconductor device, the protection unit is disconnected. The charging circuit increases the voltage of the first output pin DESAT of the driver chip to a preset value of 9V, and the second output pin OUT of the driver chip outputs a shutdown signal to the gate of the power semiconductor device to shut down the IGBT. The charging circuit accelerates the charging speed of the protection circuit and shortens the blanking time of the protection circuit. The driver chip can quickly output a shutdown signal to shut down the power semiconductor device when the voltage rises to the preset value, thereby improving the soft shutdown speed of the protection circuit and avoiding overcurrent damage to the power semiconductor device under short-circuit conditions.

[0022] As an optional implementation, in one embodiment of the invention, see Figure 1 and Figure 2As shown, the charging circuit includes: a power supply V1, a first resistor R1, and a capacitor C1. The first end of the first resistor R1 is connected to the power supply V1, the second end of the first resistor R1 is connected to the first output pin of the driver chip, the first end of the capacitor C1 is connected to the second end of the first resistor R1 and the first output pin of the driver chip, and the second end of the capacitor C1 is grounded. When the power semiconductor device is not short-circuited, the power supply V1 supplies power to the first end of the power semiconductor device, that is, the collector of the IGBT, through the first resistor R1; when the power semiconductor device is short-circuited, the protection unit between the driver chip and the power semiconductor device is disconnected, and the The power supply V1 charges the capacitor C1 through the first resistor R1 until the voltage of the first output pin DESAT of the driver chip rises to a preset value of 9V. Then, the second output pin OUT of the driver chip outputs a shutdown signal to the second end of the power semiconductor device, i.e., the gate of the IGBT, thereby shutting down and protecting the power semiconductor device. This shortens the charging time of the capacitor C1 and the blanking time of the protection circuit, thereby accelerating the response speed of the protection circuit to a short circuit. The charging current of the capacitor C1 can also be increased by reducing the resistance of the first resistor R1 and the capacitance of the capacitor C1, thereby further accelerating the charging speed of the capacitor C1. The capacitance of the capacitor C1 can be 47pF-100pF.

[0023] As an optional implementation, in one embodiment of the invention, see Figure 1 and Figure 2 As shown, the capacitor C1 is an electrolytic capacitor, which is used in conjunction with the first resistor R1 to limit the current in the circuit through its capacitive reactance characteristics to prevent excessive current shock during short circuit. The electrolytic capacitor can store a large amount of charge in a relatively small volume, that is, it has a high capacity density. The electrolytic capacitor can also withstand a higher operating voltage and has higher reliability and flexibility.

[0024] As an optional implementation, in one embodiment of the invention, see Figure 1 and Figure 2As shown, the protection unit includes: a second resistor R2 and a first diode D1. The first end of the second resistor R2 is connected to the second end of the first resistor R1 and the first output pin of the driver chip. The anode of the first diode D1 is connected to the second end of the second resistor R2, and the cathode of the first diode D1 is connected to the first end of the power semiconductor device. When the power semiconductor device is not short-circuited, the power supply V1 supplies power to the first end of the power semiconductor device, i.e., the collector of the IGBT, through the first resistor R1. The driver chip outputs a control signal to the first end of the power semiconductor device, i.e., the collector of the IGBT, through the second resistor R2 and the first diode D1. When the power semiconductor device is short-circuited, the voltage of the first end of the power semiconductor device, i.e., the collector of the IGBT, increases, and the first diode D1 is turned off. The power supply V1 then charges the capacitor C1 through the first resistor R1 until the voltage of the first output pin DESAT of the driver chip increases to a preset value of 9V. Then, the second output pin OUT of the driver chip outputs a shutdown signal to the second end of the power semiconductor device, i.e., the gate of the IGBT, thereby shutting down and protecting the power semiconductor device.

[0025] As an optional implementation, in one embodiment of the invention, see Figure 1 and Figure 2 As shown, the protection unit further includes: a second diode D2, the anode of the second diode D2 is connected to the cathode of the first diode D1, and the cathode of the second diode D2 is connected to the first end of the power semiconductor device. The first diode D1 and the second diode D2 are connected in series, and the fixed DESAT trigger threshold voltage of the driver chip is compensated by the voltage drop of the two diodes. Since Vdesat=Vce+Vd1+Vd2+Vc, that is, when the power semiconductor device is short-circuited, the fixed DESAT trigger voltage Vdesat of the driver chip is equal to The sum of the voltage Vce of the first end of the power semiconductor device, the voltage Vd1 of the first diode, the voltage Vd2 of the second diode and the voltage Vc of the capacitor, then the voltage Vd1 of the first diode and the voltage Vd2 of the second diode equivalently compensate for the trigger threshold of the protection unit by about 1.4V, reduce the voltage Vc of the capacitor C1, that is, reduce the charging time of the capacitor C1, shorten the blanking time of the protection circuit, and the driver chip can quickly output a shutdown signal to turn off the power semiconductor device when the voltage rises to the preset value of 9V, thereby improving the soft shutdown speed of the protection circuit.

[0026] As an optional implementation, in one embodiment of the invention, see Figure 2As shown, the driving protection circuit also includes: a third resistor R3 and a transistor Q1, the first end of the third resistor R3 is connected to the third output pin GATE of the driving chip, the second end of the third resistor R3 is connected to the second output pin OUT of the driving chip, the second end of the power semiconductor device, that is, the gate of the IGBT, the base of the transistor Q1 is connected to the first end of the third resistor R3, the emitter of the transistor Q1 is connected to the second end of the third resistor R3, the second output pin OUT of the driving chip, and the second end of the power semiconductor device, that is, the gate of the IGBT, the collector of the transistor Q1 is grounded, that is, connected to the negative voltage pin VNEG of the driving chip, the third resistor R3 and the transistor Q1 form a current amplification circuit, when the power semiconductor device is short-circuited and the second output pin OUT of the driving chip outputs a shutdown signal to the second end of the power semiconductor device, that is, the IGBT When the gate is turned on, the current of the gate of the power semiconductor device, i.e., the IGBT, is quickly discharged through the amplifier circuit composed of the third resistor R3 and the transistor Q1. The current discharge speed of the gate of the power semiconductor device, i.e., the IGBT, can be adjusted by adjusting the amplification factor of the transistor Q1. An orderly and smooth shutdown operation is achieved by controlling the gate voltage of the power semiconductor device, i.e., the IGBT. The current of the power semiconductor device is discharged through the amplifier circuit composed of the third resistor R3 and the transistor Q1 to slowly reduce the gate voltage to achieve soft shutdown, thereby avoiding direct hard shutdown of the power semiconductor device, which may cause excessive voltage spikes and electromagnetic interference, or even damage the device. The third resistor R3 is used to limit the current flowing into the base, ensuring that the transistor Q1 operates in a suitable amplification region or saturation region, and can also stabilize the static operating point of the transistor Q1, thereby avoiding circuit performance degradation due to temperature changes or component parameter drift.

[0027] As an optional implementation, in one embodiment of the invention, see Figure 2 As shown, the driving protection circuit also includes: a fourth resistor R4, a first end of the fourth resistor R4 is connected to the second output pin OUT of the driving chip, and a second end of the fourth resistor R4 is connected to the second end of the power semiconductor device. The fourth resistor R4 is an output resistor, which is used to limit the current output by the driving chip to prevent damage to subsequent circuits or external components due to overcurrent, and can also improve signal transmission quality, reduce reflections and interference, and the fourth resistor R4 can match the characteristic impedance of the transmission line, reduce signal reflections during transmission, and improve signal integrity.

[0028] As an optional implementation, in one embodiment of the invention, see Figure 1 and Figure 2As shown, the power semiconductor device is an insulated gate bipolar transistor or a metal oxide semiconductor field effect transistor. The insulated gate bipolar transistor has high input impedance, low on-state voltage, high current density, and is easy to drive, which makes it more effective in signal transmission, has low driving power, simple control circuit, can achieve efficient power conversion, reduce power loss, is suitable for high-power applications, and can handle larger currents; the metal oxide semiconductor field effect transistor has the advantages of high input resistance, low noise, low power consumption, large dynamic range, easy polarization, etc., and it has no secondary breakdown phenomenon and a wide safe operating area.

[0029] An embodiment of the present invention also provides a driving protection device, including the aforementioned driving protection circuit, wherein the driving protection circuit includes: a driving chip and a charging circuit, wherein the first output pin of the driving chip is used to connect to the first end of the power semiconductor device, and the second output pin of the driving chip is used to connect to the second end of the power semiconductor device. The charging circuit is arranged between the first output pin of the driving chip and the protection unit. When the power semiconductor device is short-circuited, the protection unit is disconnected, and the charging circuit increases the voltage of the first output pin of the driving chip to a preset value, and the second output pin of the driving chip outputs a shutdown signal to the second end of the power semiconductor device.

[0030] A drive protection device according to an embodiment of the present invention includes a drive protection circuit comprising a drive chip and a charging circuit. A first output pin of the drive chip is connected to a first end of a power semiconductor device, and a second output pin of the drive chip is connected to a second end of the power semiconductor device. When the power semiconductor device is an IGBT, the first output pin DESAT of the drive chip is connected to the collector of the power semiconductor device, and the second output pin OUT of the drive chip is connected to the gate of the power semiconductor device. The charging circuit is provided between the first output pin DESAT of the drive chip and a protection unit. When a short circuit occurs in the power semiconductor device, the protection unit is disconnected. The charging circuit increases the voltage of the first output pin DESAT of the drive chip to a preset value of 9V, and the second output pin OUT of the drive chip outputs a shutdown signal to the gate of the power semiconductor device to shut down the IGBT. The charging circuit accelerates the charging speed of the protection circuit and shortens the blanking time of the protection circuit. The driver chip can quickly output a shutdown signal to shut down the power semiconductor device when the voltage rises to the preset value, thereby improving the soft shutdown speed of the protection circuit and avoiding overcurrent damage to the power semiconductor device under short-circuit conditions.

[0031] An embodiment of the present invention further provides a drive protection system, comprising the aforementioned drive protection device.

[0032] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper" and "lower" is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0033] It should be noted that, in the present invention, relational terms such as "first" and "second" are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0034] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but is to be construed in the widest possible manner consistent with the principles and novel features of the present invention.

Claims

1. A driving protection circuit, characterized in that: include: A driver chip, wherein a first output pin of the driver chip is used to connect to a first end of a power semiconductor device, and a second output pin of the driver chip is used to connect to a second end of the power semiconductor device; a charging circuit, the charging circuit being provided between the first output pin of the driver chip and the protection unit; When the power semiconductor device is short-circuited, the protection unit is disconnected, the charging circuit increases the voltage of the first output pin of the driver chip to a preset value, and the second output pin of the driver chip outputs a shutdown signal to the second end of the power semiconductor device.

2. The driving protection circuit according to claim 1, characterized in that: The charging circuit comprises: power supply; a first resistor, wherein a first end of the first resistor is connected to the power supply, and a second end of the first resistor is connected to a first output pin of the driver chip; A capacitor, wherein a first end of the capacitor is connected to the second end of the first resistor and the first output pin of the driver chip, and a second end of the capacitor is grounded.

3. The driving protection circuit according to claim 2, wherein: The capacitor is an electrolytic capacitor.

4. The driving protection circuit according to claim 2, characterized in that: The protection unit includes: a second resistor, wherein a first end of the second resistor is connected to the second end of the first resistor and the first output pin of the driver chip; A first diode, wherein an anode of the first diode is connected to the second end of the second resistor, and a cathode of the first diode is connected to the first end of the power semiconductor device.

5. The driving protection circuit according to claim 4, characterized in that: The protection unit further includes: A second diode, wherein an anode of the second diode is connected to a cathode of the first diode, and a cathode of the second diode is connected to a first end of the power semiconductor device.

6. The driving protection circuit according to claim 1, characterized in that: Also includes: a third resistor, wherein a first end of the third resistor is connected to the third output pin of the driver chip, and a second end of the third resistor is connected to the second output pin of the driver chip and the second end of the power semiconductor device; A transistor, wherein the base of the transistor is connected to the first end of the third resistor, the emitter of the transistor is connected to the second end of the third resistor, the second output pin of the driver chip, and the second end of the power semiconductor device, and the collector of the transistor is grounded.

7. The driving protection circuit according to claim 1, characterized in that: Also includes: a fourth resistor, wherein a first end of the fourth resistor is connected to the second output pin of the driver chip, and a second end of the fourth resistor is connected to the second end of the power semiconductor device.

8. The driving protection circuit according to claim 1, wherein: The power semiconductor device is an insulated gate bipolar transistor or a metal oxide semiconductor field effect transistor.

9. A drive protection device, characterized in that: The drive protection circuit comprises the drive protection circuit according to any one of claims 1 to 8.

10. A drive protection system, characterized in that: Including the drive protection device according to claim 9.

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