WO2015074471A1

WO2015074471A1 - Electrostatic protection device, intelligent power module and frequency-conversion home appliance

Info

Publication number: WO2015074471A1
Application number: PCT/CN2014/089188
Authority: WO
Inventors: 冯宇翔
Original assignee: 广东美的制冷设备有限公司
Priority date: 2013-11-25
Filing date: 2014-10-22
Publication date: 2015-05-28

Abstract

An electrostatic protection device, an intelligent power module and a frequency-conversion home appliance are provided. The intelligent power module comprises: a plurality of IGBT tubes (1000); a plurality of driving tubes (2000) for driving the plurality of IGBT tubes; a driving chip (3000) controlling the plurality of IGBT tubes through the plurality of driving tubes; and at least one protective component (4000) corresponding to at least one IGBT tube of the plurality of IGBT tubes. The at least one protective component is used for performing electrostatic protection for at least one IGBT tube. Through the independent protective component being added, the IGBT tubes in the intelligent power module can be protected by the protective component when the IGBT tubes are subject to high voltage electrostatic.

Description

Electrostatic protection device, intelligent power module and frequency conversion appliance

Technical field

The present invention relates to the field of electrostatic protection technologies, and in particular, to an electrostatic protection device, an intelligent power module, and a variable frequency home appliance.

Background technique

The Intelligent Power Module, or IPM (Intelligent Power Module), is a power-driven product that combines power electronics and integrated circuit technology. The intelligent power module integrates the power switching device and the high voltage driving circuit, and has built-in fault detecting circuits such as overvoltage, overcurrent and overheating. On the one hand, the intelligent power module receives the control signal of the MCU, drives the subsequent circuit to work, and on the other hand sends the state detection signal of the system back to the MCU. Compared with the traditional discrete solution, the intelligent power module wins more and more market with its high integration and high reliability. It is especially suitable for inverters for driving motors and various inverter power supplies. An ideal power electronic device for speed, metallurgical machinery, electric traction, servo drive, and frequency conversion appliances.

However, in the prior art, smart power modules often fail, and reliability needs to be improved.

Summary of the invention

The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

In order to achieve the above object, according to an embodiment of the first aspect of the present invention, an intelligent power module is provided, comprising: a plurality of IGBT tubes; a plurality of driving tubes driving the plurality of IGBT tubes; and the plurality of driving units Controlling a driving chip of the plurality of IGBT tubes; at least one protection component corresponding to at least one of the plurality of IGBT tubes, the at least one protection component for electrostatically protecting the at least one IGBT tube .

In the technical solution, for the IGBT tube in the intelligent power module, by adding an independent protection component, when there is high voltage static electricity to the IGBT tube, such as at the ground end of the driving chip When there is a path between the gates of the IGBT tube, it can be protected by the protection component. In the embodiment of the invention, electrostatic protection can be performed in two ways:

Mode 1, the protection component can absorb static electricity, thereby preventing the IGBT tube from being subjected to electrostatic damage;

In the mode 2, the protection component protects the IGBT by disconnecting the connection between the gate of the IGBT tube and the corresponding port on the driving chip when the power supply of the driving chip is stopped.

These two protection modes will be described in detail in the following embodiments, and therefore will not be described herein.

In an embodiment of the invention, the protection component includes an electrostatic protection module for absorbing static electricity of the at least one IGBT tube.

In an embodiment of the present invention, the protection component further includes: a state determination module, coupled to the driving chip, configured to determine a power supply condition of the driving chip;

The static electricity protection module is further connected to the state determination module, configured to perform electrostatic protection on the at least one IGBT tube when the state determination module determines that the power supply of the driving chip stops power supply.

In an embodiment of the present invention, the state judging module includes: a first end connected to a power supply end corresponding to the at least one IGBT tube, detecting a power supply voltage corresponding to the IGBT tube; the second end, Connected to a corresponding ground end of the at least one IGBT tube, detecting a ground voltage corresponding to the at least one IGBT tube; a voltage comparison circuit connected to the first end and the second end, at the supply voltage and When the voltage difference of the ground voltage is greater than or equal to the preset voltage value, determining that the power supply state is normal power supply, and determining that the power supply state is stopped when the voltage difference is less than the preset voltage value powered by.

In an embodiment of the invention, when the at least one IGBT tube is an upper arm of any phase, the corresponding power supply end of the at least one IGBT tube is a power supply positive end of the high voltage region of the any phase. a ground end corresponding to the at least one IGBT tube is a power supply negative end of the high voltage region of the any phase, and when the at least one IGBT tube is a lower arm of the any phase, the at least A power supply end corresponding to an IGBT tube is a power supply power positive end of the low voltage area of the smart power module, and a corresponding ground end of the at least one IGBT tube is a power supply power negative end of the low voltage area of the smart power module.

In an embodiment of the present invention, the electrostatic protection module is configured to: switch and present corresponding circuit characteristics according to a power supply condition of the driving chip, wherein when the power of the driving chip is normally powered, The electrostatic protection module exhibits a high resistance characteristic, and the electrostatic protection module exhibits a capacitance characteristic when the power supply of the driving chip stops supplying power.

In an embodiment of the invention, the electrostatic protection module includes: a resistor and a capacitor, one end of the resistor and the anode of the capacitor are connected in parallel to the gate of the at least one IGBT tube, and the cathode of the capacitor is connected to the a grounding end corresponding to the at least one IGBT tube; a switching device, the first end of the switching device is connected to the state judging module, the second end is connected to the other end of the resistor, and the third end is connected to the at least one a corresponding grounding end of the IGBT tube; wherein the switching device closes a connection of the resistor to a ground end corresponding to the at least one IGBT tube when the power supply of the driving chip is normally powered, and stops the power supply of the driving chip When the power is supplied, the connection of the resistor to the ground end corresponding to the at least one IGBT tube is disconnected.

In an embodiment of the invention, the switching device includes: a switching transistor that saturates on when the power of the driving chip is normally powered, and is turned off when the power of the driving chip stops supplying power.

In an embodiment of the present invention, the protection component includes: a state determination module connected to the driving chip, configured to determine a power supply condition of the driving chip; and a connection control module connected to the state determining module, And configured to disconnect the gate of the at least one IGBT tube in the driving chip and the corresponding output end on the driving chip, when the state determining module determines that the power supply condition is to stop power supply, And in a case where the state determining module determines that the power supply condition is normal power supply, recovering a connection between a gate of the at least one IGBT tube and a corresponding output end on the driving chip.

In an embodiment of the present invention, the state judging module includes: a first end, connected to the a power supply end corresponding to the at least one IGBT tube, detecting a power supply voltage corresponding to the at least one IGBT tube; a second end connected to a ground end corresponding to the at least one IGBT tube, detecting a corresponding to the at least one IGBT tube a ground voltage; a voltage comparison circuit connected to the first end and the second end, determining a power supply condition when a voltage difference between the power supply voltage and the ground voltage is greater than or equal to a preset voltage value For normal power supply, when the voltage difference is less than the preset voltage value, it is determined that the power supply condition is to stop power supply.

In an embodiment of the present invention, when the at least one IGBT tube is a lower arm of any phase, a corresponding power supply end of the at least one IGBT tube is a power input end of the driving chip, and the at least one The corresponding ground end of the IGBT tube is the ground end of the driving chip.

In an embodiment of the invention, the connection control module includes: a switching device, a control end of the switching device is connected to the state judging module, and a controlled end is connected to a gate and a gate of the at least one IGBT tube Between the corresponding output terminals on the driving chip; wherein, the control terminal controls the controlled end to be turned on when the power supply condition is normal power supply, and the control terminal stops in the power supply state When the power is supplied, the controlled terminal is controlled to be disconnected.

In an embodiment of the present invention, the method further includes: a level sampling module connected to the corresponding output end of the at least one IGBT tube on the driving chip or an input end of the driving chip corresponding to the output end, a logic level state for sampling a drive signal corresponding to the at least one IGBT tube; wherein the connection control module is further coupled to the level sampling module and at a high level in the logic level state When the power supply condition is normal power supply, the connection between the gate of the at least one IGBT tube and the corresponding output end of the driving chip is restored.

In an embodiment of the present invention, the connection control module includes: a trigger, the trigger includes: a reset end, connected to the state determination module, configured to acquire the power supply status; a set end, and a connection And the level sampling module is configured to acquire a logic level state of a driving signal corresponding to the at least one IGBT tube; and an output terminal, wherein the logic level state is a high level and the power supply condition is normal In the case of power supply, the recovery signal is output, otherwise the output disconnection signal; the switching device, the control end of the switching device is connected to the output end of the flip-flop, and the controlled end is connected Between the gate of the at least one IGBT tube and a corresponding output end of the driving chip; wherein the control terminal controls the controlled end to be turned on according to the recovery signal, or is controlled according to the disconnection signal The controlled end is disconnected.

In one embodiment of the present invention, the switching device includes: a switch tube, a driving end of the switch tube is the control end, and an output end and an input end of the switch tube are the controlled end; The recovery signal is a high level signal for controlling conduction between the output end and the input end of the switch tube; the off signal is a low level signal for controlling the output end of the switch tube and Cut off between inputs.

In an embodiment of the present invention, the switching device includes: an optical coupler, the light emitting member of the optical coupler is the control end, and the light receiving member is the controlled end; wherein the light emitting member is receiving Illuminating to the recovery signal to control the light-receiving member to be turned on; and not to emit light when receiving the disconnection signal to control the light-receiving member to be turned off.

According to an embodiment of the second aspect of the present invention, there is provided a variable frequency home appliance comprising the intelligent power module as described above.

According to an embodiment of the third aspect of the present invention, an electrostatic protection device is provided, comprising: an electrostatic protection module connected to any IGBT tube in the intelligent power module for electrostatically protecting any one of the IGBT tubes.

In the technical solution, for the IGBT tube in the intelligent power module, by adding an independent electrostatic protection module, when there is high voltage static electricity to the IGBT tube, such as between the ground of the driving chip and the gate of the IGBT tube When the path is passed, the static electricity can be absorbed by the electrostatic protection module, thereby preventing the IGBT tube from being subjected to electrostatic damage.

Among them, there are many components, circuits or devices for electrostatic protection in the related art, and it is obviously applicable to the technical solutions of the present application based on the purpose of electrostatic absorption and protection, such as various types of ESD (Electro-Static Discharge). , electrostatic impedance).

In addition, the electrostatic protection device according to the above embodiment of the present invention may further have the following additional technical features:

According to an embodiment of the present invention, preferably, the method further includes: a state determining module connected to the smart power module, configured to determine a power supply condition of the smart power module; the static protection module is further connected to the state The determining module is configured to perform electrostatic protection on any one of the IGBT tubes when the state determining module determines that the power of the smart power module stops power supply.

In this technical solution, since the IGBT tube is electrostatically destroyed only when the power supply of the intelligent power module is stopped, the power supply condition of the intelligent power module is monitored, and only when the power supply is stopped. The IGBT tube is electrostatically protected, so that the protection of the IGBT tube can be performed without delay to avoid damage at the moment of power failure, and on the other hand, when the power supply is normally supplied, the electrostatic protection module can be prevented from affecting the connection. The normal operation of the IGBT tube.

Of course, the detection of the power supply state is obviously not a necessary choice. The electrostatic protection module does not necessarily affect the operating state of the IGBT tube; and, even if there is an influence, the electrostatic protection of the IGBT tube can be achieved while the IGBT tube is in a working condition. Obviously acceptable.

According to another embodiment of the present invention, preferably, the state judging module includes: a first end connected to a power supply end corresponding to any one of the IGBT tubes, and detecting a power supply voltage corresponding to the IGBT tube; a second end connected to a ground end corresponding to any one of the IGBT tubes, detecting a ground voltage corresponding to the IGBT tube; a voltage comparison circuit connected to the first end and the second end, When the voltage difference between the power supply voltage and the ground voltage is greater than or equal to a preset voltage value, determining that the power supply state is normal power supply, and determining that the power supply is when the voltage difference is less than the preset voltage value The status is to stop power supply.

In this technical solution, by comparing voltages between the power supply terminal and the ground terminal corresponding to any IGBT tube, the current power supply situation can be quickly determined. Wherein, the power supply end and the ground end of each IGBT tube may be different, for example, for the IGBT tube of the upper bridge, because it is in the high voltage area, So that its ground terminal is not 0V (and may be "high voltage" relative to the low voltage region), while the power supply terminal is the "high voltage" side with respect to the "low voltage" side ground terminal; for the lower bridge IGBT tube, due to the low voltage The region is such that its ground terminal is theoretically 0V, and the power supply terminal is opposite the "high voltage" side of the "low voltage" side ground terminal, although the "high voltage" side may be lower than the ground terminal voltage of the upper bridge IGBT tube.

Specifically, for example, when any one of the IGBT tubes is an upper arm of any phase, the corresponding power supply end of the IGBT tube is the positive end of the power supply of the high voltage region of any one of the phases, and any of the The ground terminal corresponding to the IGBT tube is the power supply negative terminal of the high voltage region of any one of the phases.

And when any one of the IGBT tubes is the lower arm of the any phase, the power supply end of the any IGBT tube is the power supply power positive end of the low voltage region of the smart power module, and any one of the IGBTs The corresponding ground terminal of the tube is the power supply negative end of the low voltage region of the intelligent power module.

Of course, for the detection of the power supply state, it is obvious that other methods can be used, such as detecting the working state of the driving chip and detecting the voltage of the power supply of the driving chip, etc., all of which can achieve accurate acquisition of the power supply state described above.

According to another embodiment of the present invention, preferably, the electrostatic protection module is configured to: switch and present corresponding circuit characteristics according to a power supply condition of the smart power module, wherein, when the power of the smart power module is During normal power supply, the electrostatic protection module exhibits a high-resistance characteristic, and when the power supply of the intelligent power module stops supplying power, the electrostatic protection module exhibits a capacitive characteristic.

In this technical solution, by changing the characteristics of the electrostatic protection module itself, it is possible to avoid switching to the high-resistance feature only by changing the connection relationship between the electrostatic protection module and the IGBT tube, so that when the IGBT tube is operated, the pair is avoided. It affects; by switching to the capacitor characteristics, when the IGBT tube is powered down, it is protected from static electricity, which helps to reduce the complexity of the circuit.

Of course, it should be understood by those skilled in the art that the electrostatic protection module can also avoid the characteristic switching, while avoiding the influence of the IGBT tube in the working state and performing the electrostatic protection in the case of power failure. For example, in a more specific case, a switch can be disposed between the electrostatic protection module and the IGBT tube, and when the intelligent power module is normally powered, the switch is disconnected and avoided. The effect of the static-free protection module on the IGBT tube, when the intelligent power module stops supplying power, the switch is closed to ensure the electrostatic protection of the IGBT tube by the electrostatic protection module.

According to another embodiment of the present invention, preferably, the electrostatic protection module includes: a resistor and a capacitor, one end of the resistor and the anode of the capacitor are connected in parallel to the gate of the any IGBT tube, and the cathode of the capacitor Connected to a corresponding ground end of any one of the IGBT tubes; a switching device, the first end of the switching device is connected to the state judging module, the second end is connected to the other end of the resistor, and the third end is connected to the a grounding end corresponding to any IGBT tube; wherein the switching device closes a connection between the resistor and a ground end corresponding to any one of the IGBT tubes when the power supply of the smart power module is normally powered, and the smart power When the power supply of the module stops supplying power, the connection of the resistor to the ground end corresponding to any one of the IGBT tubes is disconnected.

In this technical solution, specific types and characteristic values of the resistors and capacitors should be selected and set so that when switched to the resistor, a high-resistance state can be exhibited, and when switching to the capacitor, static electricity can be effectively absorbed.

For the switching device, obviously there are various options, such as relays; and in order to reduce the complexity of the circuit construction and improve the switching efficiency, as a specific embodiment, a switching tube can be used, and the switching tube is in the above intelligent power. When the power supply of the module is normally powered, the saturation is turned on, and the power is turned off when the power supply of the intelligent power module stops supplying power.

According to an embodiment of the fourth aspect of the present invention, an intelligent power module is provided, comprising at least one electrostatic protection device according to any one of the preceding aspects.

According to an embodiment of the fifth aspect of the present invention, a frequency conversion home appliance is provided, including the above intelligent power module, such as an inverter air conditioner, an inverter refrigerator, a frequency conversion washing machine, and the like.

Through the above technical solution, the high-voltage static electricity of the grounding end can be prevented from causing damage to the IGBT tube when the intelligent power module is powered off, and the use safety of the intelligent power module is ensured, and the service life thereof is prolonged.

According to an embodiment of the sixth aspect of the present invention, an electrostatic protection device is provided, comprising: The state judging module is connected to the smart power module for determining the power supply status of the smart power module; the connection control module is connected to the state judging module, and configured to determine, in the state judging module, that the power supply status is Disconnecting the power supply, disconnecting a gate of any one of the IGBT tubes of the smart power module from a corresponding output terminal of the driver chip in the smart power module, and determining, by the state determination module, the power source In the case where the power supply condition is normal power supply, the connection between the gate of any one of the IGBT tubes and the corresponding output terminal on the drive chip is restored.

In this technical solution, since the electric charge on the circuit is in a dynamic circulation state when the intelligent power module is in an operating state, no electrostatic shock is generated; and when the intelligent power module is in an inoperative state, since the electric charge cannot be circulated, A large amount of electrostatic charge can cause damage to the IGBT tube.

Therefore, by judging the power supply status of the intelligent power module, it is possible to understand the charge flow in the circuit, so that when the power supply of the intelligent power module stops supplying power, the IGBT tube is protected in time to avoid damage by electrostatic shock. And influence.

At the same time, when the power supply of the intelligent power module is stopped, the connection between the gate of the IGBT tube and the corresponding port on the driving chip is disconnected in time, so that the gate of the IGBT tube is equivalent to being in a floating state, and the electrostatic charge cannot pass through the IGBT tube. The gate and the emitter can not cause damage to the IGBT tube, thereby effectively avoiding the risk of breakdown of the IGBT tube by the high voltage static electricity.

According to an embodiment of the present invention, preferably, the state determining module includes: a first end connected to a power supply end corresponding to any one of the IGBT tubes, detecting a power supply voltage corresponding to the any IGBT tube; a second end connected to the corresponding ground of the IGBT tube, detecting a ground voltage corresponding to the IGBT tube; a voltage comparison circuit connected to the first end and the second end, in the power supply When the voltage difference between the voltage and the ground voltage is greater than or equal to the preset voltage value, determining that the power supply condition is normal power supply, and determining that the power supply status is when the voltage difference is less than the preset voltage value To stop powering.

In this technical solution, by comparing voltages between the power supply terminal and the ground terminal corresponding to any IGBT tube, the current power supply situation can be quickly determined. Wherein, the power supply end and the ground end of each IGBT tube may be different, for example, for the IGBT tube of the upper bridge, because it is in the high voltage area, the ground end is not 0V (and may be "high voltage" relative to the low voltage area "), and the power supply end is relative to the "high voltage" side of the "low voltage" side ground; for the lower bridge IGBT tube, because it is in the low voltage region, the ground terminal is theoretically 0V, and the power supply terminal is relative to The "high voltage" side of the "low voltage" side ground terminal, although the "high voltage" side may be lower than the ground terminal voltage of the upper bridge IGBT tube.

When the IGBT tube is the lower arm of any one of the phases, the power supply end of the IGBT tube is the power supply positive end of the low voltage region of the smart power module (such as the power supply of the driving chip). The input end), the corresponding ground end of any one of the IGBT tubes is the power supply negative end of the low voltage region of the intelligent power module (such as the ground end of the driving chip).

As a more specific implementation manner, the connection control module includes: a switching device, a control end of the switching device is connected to the state judging module, and a controlled end is connected to a gate and a gate of the any IGBT tube Between the corresponding output terminals on the driving chip; wherein, the control terminal controls the controlled end to be turned on when the power supply condition is normal power supply, and the control terminal stops in the power supply state When the power is supplied, the controlled terminal is controlled to be disconnected.

In the technical solution, the control end controls the connection status of the controlled end according to the power supply status of the intelligent power module, so that when the power supply of the intelligent power module is normally powered, the controlled end is kept turned on to ensure the IGBT tube. Normal operation; when the power of the intelligent power module is stopped, The controlled controlled end is disconnected to ensure that the IGBT tube is not damaged by electrostatic shock, which improves the working safety of the intelligent power module.

According to another embodiment of the present invention, preferably, the smart power module further includes: a level sampling module connected to the corresponding output end of the IGBT transistor on the driving chip or the driving chip corresponding to the An input end of the output terminal for sampling a logic level state of a driving signal corresponding to any one of the IGBT tubes; wherein the connection control module is further connected to the level sampling module and at the logic level When the state is high and the power supply condition is normal power supply, the connection between the gate of any one of the IGBT tubes and the corresponding output terminal on the driving chip is restored.

In the technical solution, in the case that the intelligent power module is normally powered, the logic level state of the driving control signal corresponding to any one of the IGBT tubes is further sampled, so that only when the level state is high level, After the smart power module actually enters the working state, it is allowed to turn on the gate of any of the IGBT tubes to prevent the residual electrostatic charge in the circuit from affecting the IGBT tube, thereby contributing to further improving the safety of the smart power module.

As a preferred embodiment, the connection control module includes: a trigger, the trigger includes: a reset end, and is connected to the state determining module, configured to acquire the power supply status; the set end, and the connection And the level sampling module is configured to acquire a logic level state of a driving signal corresponding to any one of the IGBT tubes; and an output terminal, wherein the logic level state is a high level and the power supply condition is normal In the case of power supply, the recovery signal is output, otherwise the output is disconnected; the switching device, the control end of the switching device is connected to the output of the flip-flop, the controlled end is connected to the gate of any of the IGBT tubes and Between the corresponding output terminals on the driving chip; wherein the control terminal controls the controlled terminal to be turned on according to the recovery signal, or controls the controlled terminal to be disconnected according to the disconnection signal.

In this technical solution, by using the trigger, it is possible to ensure the logic level state of the power supply state of the smart power module and the driving signal of any of the IGBT tubes, thereby ensuring the gate of any of the IGBT tubes. The pole connection state is accurately controlled.

At the same time, the control terminal can also be controlled according to the signal output of the output of the trigger. The control of the connection status of the terminal enables the controlled end to be turned on when the power supply of the intelligent power module is normally powered and in operation, to ensure the normal operation of the IGBT tube; and the power supply of the intelligent power module is stopped, or the power supply is normally powered. However, when it is not in operation, the control controlled end is disconnected to ensure that the IGBT tube is not damaged by electrostatic shock, thereby improving the working safety of the intelligent power module.

As a preferred embodiment, the switching device includes: a switch tube, a driving end of the switch tube is the control end, and an output end and an input end of the switch tube are the controlled end; The recovery signal is a high level signal for controlling conduction between the output end and the input end of the switch tube; the off signal is a low level signal for controlling the output end of the switch tube and Cut off between inputs.

Of course, there are many ways to select a switching device, that is, those skilled in the art can implement the selection of the switching device according to their actual needs. For example, in another specific implementation manner, the switching device may further include:

An optical coupler, wherein the light-emitting member of the optical coupler is the control end, and the light-receiving member is the controlled end; wherein the light-emitting member emits light when receiving the recovery signal to control the light-receiving member And not emitting light when receiving the disconnection signal to control the light-receiving member to be disconnected.

According to an embodiment of the seventh aspect of the present invention, an intelligent power module is provided, comprising at least one of the electrostatic protection devices described in any one of the above aspects.

According to an embodiment of the eighth aspect of the present invention, a frequency conversion home appliance is provided, including the above intelligent power module, such as an inverter air conditioner, an inverter refrigerator, a frequency conversion washing machine, and the like.

The additional aspects and advantages of the invention will be set forth in part in the description which follows.

DRAWINGS

FIG. 1 is a schematic structural diagram of an intelligent power module in the related art;

2 is a schematic structural diagram of an intelligent power module according to an embodiment of the present invention;

3A is a circuit diagram showing an electrostatic protection device for an IGBT tube of an upper bridge arm according to an embodiment of the present invention;

3B is a circuit diagram showing an electrostatic protection device for an IGBT tube of a lower arm according to an embodiment of the present invention;

4 is a schematic structural diagram of an intelligent power module according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of an intelligent power module according to another embodiment of the present invention; FIG.

FIG. 6 is a schematic structural view of an electrostatic protection module according to an embodiment of the present invention; FIG.

7 is a schematic structural diagram of an electrostatic protection module of the embodiment shown in FIG. 6;

FIG. 8 is a block diagram showing the structure of an electrostatic protection device according to an embodiment of the present invention; FIG.

9A is a circuit diagram showing an electrostatic protection device for an IGBT tube of an upper bridge arm according to an embodiment of the present invention;

9B is a circuit diagram showing an electrostatic protection device for an IGBT tube of a lower arm according to an embodiment of the present invention;

FIG. 10 is a schematic view showing a device connection structure of an electrostatic protection device according to an embodiment of the present invention; FIG.

11 is a circuit diagram showing an electrostatic protection device for an IGBT tube of a lower arm according to another embodiment of the present invention;

FIG. 12 is a schematic view showing a device connection structure of an electrostatic protection device according to another embodiment of the present invention; FIG.

FIG. 13 is a schematic diagram showing the overall device connection structure of an electrostatic protection device according to an embodiment of the present invention; FIG.

FIG. 14 is a schematic view showing the overall device connection structure of an electrostatic protection device according to another embodiment of the present invention; FIG.

Figure 15 is a block diagram showing the construction of an intelligent power module including an electrostatic protection device in accordance with one embodiment of the present invention.

Detailed ways

The present invention will be further described in detail below with reference to the drawings and specific embodiments. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to facilitate a full understanding of the invention, but the invention may be practiced in other embodiments than described herein. Limitations of the embodiments.

The applicant analyzed the fault mechanism of the intelligent power module in detail and found that the fault of the intelligent power module is usually caused by the IGBT failure caused by static electricity. The applicant's analysis of the fault mechanism is as follows:

In the related art, the circuit structure of the intelligent power module 100 is as shown in FIG. 1:

The power supply positive terminal VCC of the control circuit 1000 is connected to the source and the substrate of the PMOS transistor 1010, the source and the substrate of the PMOS transistor 1013, the source of the PMOS transistor 1016, and the substrate, and serves as the smart power module 100. The low-voltage area power supply positive terminal VDD, VDD is generally 15V.

The HIN1 end of the control circuit 1000 serves as the U-phase upper arm input end UHIN of the intelligent power module 100; the HIN2 end of the control circuit 1000 serves as the V-phase upper arm input end VHIN of the intelligent power module 100; The HIN3 end of the control circuit 1000 serves as the W-phase upper arm input terminal WHIN of the intelligent power module 100; the LIN1 end of the control circuit 1000 serves as the U-phase lower-arm input terminal ULIN of the intelligent power module 100; The LIN2 end of the control circuit 1000 serves as the V-phase lower arm input end VLIN of the intelligent power module 100; the LIN3 end of the control circuit 1000 serves as the W-phase lower arm input end WLIN of the intelligent power module 100. Here, the six inputs of the U, V, and W three phases of the smart power module 100 receive an input signal of 0 to 5V.

The GND end of the control circuit 1000 serves as a low-voltage area power supply negative terminal COM of the smart power module 100.

The VB1 end of the control circuit 1000 is connected to the source of the PMOS transistor 1001 and the substrate, and serves as the U-phase high voltage region power supply positive terminal UVB of the intelligent power module 100; the OUT1 end of the control circuit 1000 and the The gate of the PMOS transistor 1001 and the gate of the NMOS transistor 1002 are connected; the drain of the PMOS transistor 1001 is connected to the drain of the NMOS transistor 1002 and is referred to as the HO1 terminal, and the HO1 terminal and the U-phase upper arm IGBT transistor 121 The gate of the control circuit 1000 is connected to the source and the substrate of the NMOS transistor 1002, the emitter of the IGBT transistor 121, the anode of the FRD transistor 111, and the U-phase lower arm IGBT tube 124. The collector, the cathode of the FRD tube 114 is connected, and serves as the negative terminal U of the U-phase high voltage region of the intelligent power module 100.

The VB2 end of the control circuit 1000 is connected to the source of the PMOS transistor 1004 and the substrate, and serves as the V-phase high voltage region power supply positive terminal VVB of the smart power module 100; the OUT2 end of the control circuit 1000 and the The gate of the PMOS transistor 1004 and the gate of the NMOS transistor 1005 are connected; the drain of the PMOS transistor 1004 is connected to the drain of the NMOS transistor 1005 and is referred to as the HO2 terminal, and the HO2 terminal and the V-phase upper arm IGBT transistor 122 The gate of the control circuit 1000 is connected to the source and the substrate of the NMOS transistor 1005, the emitter of the IGBT transistor 122, the anode of the FRD transistor 112, and the U-phase lower arm IGBT tube 125. The collector, the cathode of the FRD tube 115 is connected, and serves as the negative terminal V of the V-phase high voltage region of the intelligent power module 100.

The VB3 end of the control circuit 1000 is connected to the source of the PMOS transistor 1007 and the substrate, and serves as the W-phase high voltage region power supply positive terminal WVB of the smart power module 100; the OUT3 end of the control circuit 1000 and the The gate of the PMOS transistor 1007 and the gate of the NMOS transistor 1008 are connected; the drain of the PMOS transistor 1007 is connected to the drain of the NMOS transistor 1008 and is referred to as the HO3 terminal, and the HO3 terminal and the W phase upper arm IGBT tube 123 are connected. The gate of the control circuit 1000 is connected to the VS3 terminal of the control circuit 1000 and the source and substrate of the NMOS transistor 1008, the emitter of the IGBT transistor 123, the anode of the FRD transistor 113, and the W-phase lower arm IGBT tube 126. The collector, the cathode of the FRD tube 116 is connected, and serves as the power supply negative terminal W of the W-phase high voltage region of the intelligent power module 100.

a collector of the IGBT tube 121, a collector of the IGBT tube 122, a collector of the IGBT tube 123, a cathode of the FRD tube 111, a cathode of the FRD tube 112, the The cathode of the FRD tube 113 is connected and serves as the high voltage input terminal P of the smart power module 100, and P is generally connected to 300V.

The OUT4 end of the control circuit 1000 is connected to the gate of the PMOS transistor 1010 and the gate of the NMOS transistor 1011; the drain of the PMOS transistor 1010 is connected to the drain of the NMOS transistor 1011 and is recorded as the LO1 terminal. The LO1 terminal is connected to the gate of the U-phase lower arm IGBT tube 124.

The OUT5 end of the control circuit 1000 is connected to the gate of the PMOS transistor 1013 and the gate of the NMOS transistor 1014; the drain of the PMOS transistor 1013 is connected to the drain of the NMOS transistor 1014 and is recorded as the LO2 terminal. The LO2 terminal is connected to the gate of the V-phase lower arm IGBT tube 125. The OUT6 end of the control circuit 1000 is connected to the gate of the PMOS transistor 1016 and the gate of the NMOS transistor 1017; the drain of the PMOS transistor 1016 is connected to the drain of the NMOS transistor 1017 and is recorded as the LO3 terminal. The LO3 terminal is connected to the gate of the W-phase lower arm IGBT tube 126. a substrate and a source of the NMOS transistor 1011, a substrate and a source of the NMOS transistor 1014, a substrate and a source of the NMOS transistor 1017, and a power supply of a low-voltage region of the smart power module 100 Negative COM.

The emitter of the IGBT tube 124, the emitter of the IGBT tube 125, the emitter of the IGBT tube 126, the anode of the FRD tube 114, the anode of the FRD tube 115, and the anode of the FRD tube 116. Connected to one end of the sampling resistor 130 and used as the current detecting terminal ISO of the smart power module 100.

The other end of the resistor 130 is connected to the low voltage power supply negative terminal COM of the smart power module 100. In practical applications, the U, V, and W terminals of the smart power module 100 are connected to the three phases of the motor 200.

Based on the above connection structure, the functions of the control circuit 1000 include:

The 0~5V logic signals of the input terminals HIN1, HIN2, HIN3 and LIN1, LIN2, LIN3 are respectively transmitted to the output terminals OUT1, OUT2, OUT3 and OUT4, OUT5, OUT6, where HO1 is VS1~VS1+15V, HO2 is VS2 ~ VS2+15V, HO3 is the logic signal of VS3 ~ VS3 + 15V, LO1, LO2, LO3 is the logic signal of 0 ~ 15V.

Among them, the circuit part connected to OUT1~OUT6 adopts the COMS structure, and the structure of the six outputs is exactly the same. Take OUT6 as an example for description: when OUT6 outputs a high level, LO3 outputs a low level; when OUT6 inputs a low level, the LO3 output is high. Level.

However, the MOS transistor is generally connected with a parasitic diode. As shown in FIG. 1, the NMOS transistor 1017 has a parasitic diode 1018 between the substrate and the drain, that is, a parasitic diode 1018 between COM and LO3.

Since the application environment of the smart power module 100 is very malicious, it generally works in a high temperature and dry environment for a long time. When the smart power module 100 works, a high switching speed is required to ensure that the heat generation of the smart power module 100 is as small as possible and does not work. The smart power module 100 needs to withstand static electricity of 2000V to 3000V.

Especially for the three IGBT tubes of the lower arm, namely the IGBT tube 124, the IGBT tube 125 and the IGBT tube 126, although the collector is connected to the motor, the emitter is connected to the ISO end, and the ISO end is connected to the MCU (not shown) The small signal is easy to be affected by static electricity. Once there is positive static electricity between COM and ISO, the path to the gate of the three IGBT tubes is formed, which are:

COM→parasitic diode 1012→ IGBT tube 124 gate→IGBT tube 124 emitter→ISO;

COM→parasitic diode 1015→IGBT tube 125 gate→IGBT tube 125 emitter→ISO;

COM→parasitic diode 1018→gate of IGBT tube 126→ emitter of IGBT tube 126→ISO.

Therefore, in the practical application of the smart power module 100, the probability of the IGBT tube of the lower arm being damaged by static electricity is large; and when the IGBT tube of the lower arm is damaged, it is easy to cause the upper and lower arms to be simultaneously turned on, resulting in intelligence. The power module current is out of control and causes an explosion.

In the related art, the antistatic ability of the gate of the IGBT tube itself is increased mainly by increasing the thickness of the gate oxide. In order to enhance the antistatic capability of the IGBT tube of the lower bridge arm, an IGBT tube having a thick gate oxide thickness is sometimes used in the lower arm. However, in this way, the switching speed of the intelligent power module 100 will be seriously degraded, especially in the process of switching the IGBT tube switch of the upper and lower arms, because the switching speed of the upper and lower arms IGBT tubes does not match, resulting in the switching of the intelligent power module 100. The loss is extremely high. For the use of switching frequency above kilohertz, it will cause a lot of heat, even if the heat sink is as large as possible. The operating temperature of the intelligent power module 100 is higher than the ambient temperature by more than 60 ° C. When the intelligent power module 100 is operated in a high temperature environment for a long time, the performance degradation is severe and the service life is shortened.

If the upper and lower arms are both IGBT tubes with thick gate oxide thickness, although the switching speeds of the IGBT tubes of the upper and lower arms are matched, the overall switching characteristics are still lower than the IGBT tubes with thin gate oxide thickness, so the working performance is very good. not ideal.

Therefore, how to ensure that the IGBT tube has a high switching speed, and can have high safety and avoid electrostatic damage, has become a technical problem to be solved.

In order to solve the above problem, an embodiment of the present invention provides an intelligent power module. As shown in FIG. 2, the smart power module includes: a plurality of IGBT tubes 1000; a plurality of driving tubes 2000 driving the plurality of IGBT tubes 1000; and controlling the plurality of IGBT tubes 1000 through the plurality of driving tubes 2000 a driving chip 3000; at least one protection component 4000 corresponding to at least one of the plurality of IGBT tubes 1000, the at least one protection component 4000 for electrostatically protecting the at least one IGBT tube 1000. In this technical solution, for the IGBT tube 1000 in the smart power module, by adding an independent protection component 4000, when there is high voltage static electricity to the IGBT tube 1000, such as the ground of the driving chip 3000 and the gate of the IGBT tube 1000 When there is a path between the poles, it can be protected by the protection component 4000.

In the embodiment of the invention, electrostatic protection can be performed in two ways:

In the first mode, the protection component 4000 can absorb static electricity, thereby preventing the IGBT tube from being subjected to electrostatic damage;

In the second mode, the protection component 4000 protects the IGBT by disconnecting the connection between the gate of the IGBT tube and the corresponding port on the driving chip when the power supply of the driving chip is stopped.

The following two methods are described in detail:

Method 1:

In this embodiment, mainly by adding an electrostatic absorption module, that is, an electrostatic protection module, specifically as follows:

Based on the object of the present invention, that is, for electrostatic protection of an IGBT tube in an intelligent power module, the present invention provides an electrostatic protection device capable of performing static electricity on any of the IGBT tubes (ie, corresponding to at least one of the IGBT tubes described above) protection.

Based on the specific structure of the smart power module 100 shown in FIG. 1 , for each phase line, an upper bridge IGBT tube corresponding to the high voltage region and a lower bridge IGBT tube corresponding to the low voltage region are included, for example, for the U phase. For the line, the IGBT tube 121 is the upper arm and the IGBT tube 124 is the lower arm. For convenience of explanation, the specific connection relationship of the electrostatic protection device will be described in detail below for the IGBT tubes of the upper arm and the lower arm.

3A is a circuit diagram showing the electrostatic protection device for an IGBT tube of an upper bridge arm according to an embodiment of the present invention.

As shown in FIG. 3A, the protection component includes: an electrostatic protection module 302. The electrostatic protection module 302 is connected to any one of the smart power modules for electrostatic protection of any of the IGBT tubes.

For convenience of explanation, in the technical solution shown in FIG. 3A, the electrostatic protection module 302 is connected to an upper bridge IGBT tube (ie, the IGBT 121 shown in FIG. 1) in the U-phase line. Specifically, the gate connected to the upper bridge IGBT tube in FIG. 3A indicates connection to the IGBT tube.

By adding an independent electrostatic protection module 302, when there is high voltage static electricity to the IGBT tube, such as when there is a path between the ground end of the driving chip and the gate of the IGBT tube, the static electricity can be absorbed by the electrostatic protection module 302. In order to avoid electrostatic breakdown of the IGBT tube.

Among them, there are many components, circuits or devices for electrostatic protection in the related art, and it is obviously applicable to the technical solution of the present application as the electrostatic protection module 302, for example, various types based on the purpose of electrostatic absorption and protection. ESD (Electro-Static Discharge).

As a preferred solution, the electrostatic protection device may further include: a state determining module 304 connected to the driving chip, configured to determine a power supply condition of the driving chip; the static protection module 302 is further connected to the state a determining module 304, configured to: in the state determining module 304 When it is determined that the power supply of the driving chip is stopped, the IGBT tube is electrostatically protected.

In this technical solution, since only the power supply of the intelligent power module (mainly the driving chip and the subsequent introduction of the intelligent power module) stops supplying power, the possibility that the IGBT tube is electrostatically destroyed is adopted, and the smart power module is passed. The monitoring of the power supply condition and the electrostatic protection of the IGBT tube only when the power supply is stopped, so that on the one hand, the protection of the IGBT tube can be performed without delay, so as to avoid damage at the moment of power failure, on the other hand, When the power supply is normally powered, the electrostatic protection module 302 can be prevented from affecting the normal operation of the connected IGBT tube.

Of course, the detection of the power supply state is obviously not a necessary choice. The electrostatic protection module 302 does not necessarily affect the operating state of the IGBT tube; and, even if there is an influence, it can achieve electrostatic protection to the IGBT tube while being within a certain range in the case where the IGBT tube is in an operating state. The impact is clearly acceptable.

3B is a circuit diagram showing the electrostatic protection device for an IGBT tube of a lower arm according to an embodiment of the present invention.

As shown in FIG. 3B, similarly, for the lower bridge IGBT tube in the smart power module, the static protection device may also include: an electrostatic protection module 302. The electrostatic protection module 302 is connected to any one of the smart power modules for electrostatic protection of any of the IGBT tubes.

For convenience of explanation, in the technical solution shown in FIG. 3B, the electrostatic protection module 302 is connected to the lower bridge IGBT tube in the U-phase line (ie, the IGBT 126 shown in FIG. 1), that is, the lower IGBT tube in FIG. 3B. The upper IGBT tube is the upper bridge IGBT tube in the U-phase line. Specifically, the gate connected to the lower bridge IGBT tube in FIG. 3B indicates connection to the IGBT tube.

Similarly, as a preferred solution, the static electricity protection device may further include: a state determining module 304 connected to the smart power module, configured to determine a power supply state of the smart power module; The state determining module 304 is configured to perform electrostatic protection on the IGBT tube when the state determining module 304 determines that the power of the smart power module stops power supply.

In the circuit connection structure of the upper arm and the lower arm shown in FIG. 3A and FIG. 3B respectively, as a specific circuit structure and connection manner, the state judging module 304 may specifically include:

The first end is connected to the power supply end corresponding to any one of the IGBT tubes, and detects a power supply voltage corresponding to any one of the IGBT tubes; the second end is connected to a corresponding ground end of the any IGBT tube, and the detection corresponds to a ground voltage of any one of the IGBT tubes; a voltage comparison circuit connected to the first end and the second end, when a voltage difference between the supply voltage and the ground voltage is greater than or equal to a preset voltage value And determining that the power supply state is normal power supply, and determining that the power supply state is to stop power supply when the voltage difference is less than the preset voltage value.

Wherein, corresponding to the case shown in FIG. 3A, since the upper bridge arm IGBT tube is located in the high voltage region, the ground end thereof is opposite ground, that is, not 0V, and may even be "high voltage" with respect to the low voltage region, and The power supply terminal is also the "high voltage" side with respect to the "low voltage" side ground terminal. Therefore, the first end, that is, the end point A1, is connected to the UVB end, and the second end, that is, the end point B1, is connected to the UVS end.

Corresponding to the case shown in FIG. 3B, since the lower arm IGBT tube is located in the low voltage region, its ground terminal is theoretically 0V, and the power supply terminal is opposite to the "high voltage" side of the "low voltage" side ground terminal, although The "high voltage" side may be lower than the ground terminal voltage of the upper bridge IGBT tube. Therefore, the first terminal, that is, the terminal A2, is connected to the power supply VDD of the driving circuit 101, and the second terminal, that is, the terminal B2, is connected to the UN terminal.

As a specific detection method of the power supply state, the detection of the opposite power supply terminal and the ground terminal of an IGBT tube shown in FIG. 3A and FIG. 3B can quickly react to the voltage change on the line, thereby quickly determining The current power supply situation is taken to avoid the IGBT tube being damaged by high voltage static electricity when the power is turned off.

FIG. 4 shows a schematic structural diagram of an intelligent power module according to an embodiment of the present invention.

As shown in FIG. 4, each of the IGBT tubes in the smart power module 10 applies the electrostatic protection device shown in FIG. 3A or FIG. 3B, that is, “ESD tolerance boost circuits 41 to 46” to achieve electrostatic protection against the IGBT tubes. .

The specific line structure of the smart power module 10 includes:

The VCC of the driving circuit (or driving chip) 40 serves as the VDD terminal of the smart power module 10, and VDD is the low-voltage region power supply of the smart power module 10, and VDD is generally 15V.

The HIN1 end of the driving circuit 40 serves as the U-phase upper arm input end UHIN of the intelligent power module 10; the HIN2 end of the driving circuit 40 serves as the V-phase upper arm input end VHIN of the intelligent power module 10; The HIN3 end of the driving circuit 40 serves as the W-phase upper arm input terminal WHIN of the smart power module 10; the LIN1 end of the driving circuit 40 serves as the U-phase lower arm input terminal ULIN of the intelligent power module 10; The LIN2 end of the driving circuit 40 serves as the V-phase lower arm input terminal VLIN of the intelligent power module 10; the LIN3 terminal of the driving circuit 40 serves as the W-phase lower arm input terminal WLIN of the intelligent power module 10. (Here, the six inputs of the U, V, and W three phases of the intelligent power module 10 receive 0 to 5 V input signals)

The VB1 end of the driving circuit 40 is connected to the first input and output end of the ESD tolerance increasing circuit 41 and serves as the U-phase high voltage area power supply positive terminal UVB of the intelligent power module 10; the VB2 end and the ESD of the driving circuit 40 The first input and output ends of the tolerance boosting circuit 42 are connected and serve as the V-phase high voltage region power supply positive terminal VVB of the smart power module 10; the VB3 terminal of the driving circuit 40 and the first input and output terminals of the ESD tolerance boosting circuit 43 Connected and used as the W-phase high voltage area power supply positive terminal WVB of the intelligent power module 10.

The VS1 end of the driving circuit 40 is connected to the second input and output end of the ESD tolerance increasing circuit 41, the emitter of the IGBT tube 21, the anode of the FRD tube 11, the collector of the IGBT tube 24, and the cathode of the FRD tube 14. And as the U-phase high-voltage area power supply negative terminal UVS of the intelligent power module 10; the VS2 end of the driving circuit 40 and the second input and output end of the ESD tolerance improving circuit 42, the emitter of the IGBT tube 22, and the FRD The anode of the tube 12, the collector of the IGBT tube 25, and the cathode of the FRD tube 15 are connected, and serve as the V-phase high-voltage region power supply negative terminal VVS of the intelligent power module 10; the VS3 terminal and the ESD tolerance of the driving circuit 40 are improved. The second input and output end of the circuit 43, the emitter of the IGBT tube 23, the anode of the FRD tube 13, the collector of the IGBT tube 26, the cathode of the FRD tube 16, and the W-phase high voltage of the smart power module 10 Zone power supply negative terminal WVS.

The collector of the IGBT tube 21, the cathode of the FRD tube 11, the collector of the IGBT tube 22, the cathode of the FRD tube 12, the collector of the IGBT tube 23, and the cathode of the FRD tube 13 Connected, and as the high voltage input terminal P of the intelligent power module 10, P is generally connected to 300V.

The emitter of the IGBT tube 24 is connected to the anode of the FRD tube 14 and the third input and output end of the ESD tolerance boosting circuit 44, and serves as a U-phase low voltage reference terminal UN of the intelligent power module 10; The emitter of the tube 25 is connected to the anode of the FRD tube 15, the third input and output of the ESD tolerance boost circuit 45, and serves as the V-phase low voltage reference terminal VN of the smart power module 10; The emitter is connected to the anode of the FRD tube 16, the third input and output of the ESD tolerance boost circuit 46, and serves as the W-phase low voltage reference terminal WN of the smart power module 10.

The HO1 end of the driving circuit 40 is connected to the gate of the IGBT tube 21 and the third input and output end of the ESD tolerance increasing circuit 41; the HO2 end of the driving circuit 40 and the gate of the IGBT tube 22, the ESD The third input and output terminals of the uptake circuit 42 are connected; the HO3 end of the drive circuit 40 is connected to the gate of the IGBT transistor 23 and the third input and output of the ESD tolerance boost circuit 43.

The LO1 end of the driving circuit 40 is connected to the gate of the IGBT tube 24 and the third input and output end of the ESD tolerance boosting circuit 44; the LO2 end of the driving circuit 40 and the gate of the IGBT tube 25, the ESD The third input and output ends of the uptake circuit 45 are connected; the LO3 end of the drive circuit 40 is connected to the gate of the IGBT tube 26 and the third input and output of the ESD tolerance boost circuit 46.

The function of the driving circuit 40 is to receive the 0~5V signals of the six input terminals UHIN, VHIN, WHIN, ULIN, VLIN, and WLIN, and transmit them to the output terminals HO1, HO2, HO3, and LO1, LO2, and LO3, respectively, where HO1 is HO2 and HO3 are logic signals of VS~VS+15V, and LO1, LO2, and LO3 are logic signals of 0-15V. It functions exactly the same as the HVIC tube 101 of the prior art.

At the same time, the ESD tolerance boosting circuit 41, the ESD tolerance boosting circuit 42, the ESD tolerance boosting circuit 43, the ESD tolerance boosting circuit 44, the ESD tolerance boosting circuit 45, and the ESD tolerance boosting circuit 46 The structure and function are identical and are connected to the respective IGBT tubes.

Of course, although FIG. 3A and FIG. 3B show a specific detection mode of the power supply state, it is obvious that other methods can be used for detecting the power supply state, such as detecting the working state of the driving chip and detecting the driving. The voltage of the power supply of the chip, etc., can achieve accurate acquisition of the power supply state described above. A more specific detection method will be described in detail below with reference to FIG. 5.

FIG. 5 shows a schematic structural diagram of an intelligent power module according to another embodiment of the present invention.

As shown in FIG. 5, in the smart power module, only one state detecting module 304 is included, which is connected to the power supply VDD side of the driving chip 101 for directly detecting the power supply condition on the VDD side.

At the same time, each IGBT tube is connected to an ESD protection module 302, and the status detection module 304 is respectively connected to each ESD protection module 302, and the detected power supply status is simultaneously fed back to all the ESD protection modules 302, Determine if static protection is performed.

In the technical solution of the present invention, a specific protection mode is proposed for the electrostatic protection module 302 in any one of the foregoing technical solutions, including: the electrostatic protection module 302 switches and presents according to the power supply status of the intelligent power module. Corresponding circuit characteristics, wherein the electrostatic protection module 302 exhibits a high-resistance characteristic when the power supply of the intelligent power module is normally powered. When the power supply of the intelligent power module stops supplying power, the electrostatic protection module 302 presents Capacitance characteristics.

FIG. 6 shows a schematic structural view of an electrostatic protection module according to an embodiment of the present invention.

As shown in FIG. 6 , as a more specific embodiment, taking the lower-arm IGBT tube in the U-phase line as an example, the electrostatic protection module 302 includes a resistor R and a capacitor C, and one end of the resistor R and the capacitor C The positive pole is connected in parallel to the gate of any one of the IGBT tubes, and the cathode of the capacitor C is connected to the ground terminal UN corresponding to any one of the IGBT tubes; the switching device 302A, the first end of the switching device 302A is connected to The state determining module 304 is connected to the other end of the resistor R, and the third end is connected to the ground terminal UN corresponding to any one of the IGBT tubes. The switching device 302A is in the smart power module. When the power supply is normally powered, the connection of the resistor R to the ground terminal UN corresponding to any one of the IGBT tubes is closed, and when the power supply of the intelligent power module stops supplying power, the resistor R and the any IGBT are disconnected. The connection of the corresponding ground terminal UN of the tube.

In this technical solution, the specific model and characteristic values of the resistor R and the capacitor C should be selected and set so that when switching to the resistor R, a high-resistance state can be exhibited, and when switching to the capacitor C, the static electricity can be applied. Perform effective absorption.

For the switching device 302A, obviously there are various options, such as relays; and in order to reduce the complexity of the circuit construction and improve the switching efficiency, as a specific embodiment, FIG. 7 shows the embodiment of FIG. A schematic structural diagram of the electrostatic protection module 302.

As shown in FIG. 7 , a switch tube N (shown as an NMOS tube in FIG. 7 ) may be used, and the switch tube N saturates and conducts when the power supply of the smart power module is normally powered, and the power supply of the smart power module stops. Cut off when power is supplied.

Of course, it should be understood by those skilled in the art that the electrostatic protection module 302 can also avoid the characteristic switching, while avoiding the influence of the IGBT tube in the working state, and performing electrostatic protection in the case of power failure. For example, in a more specific case (not shown), a switch can be disposed between the electrostatic protection module 302 and the IGBT tube, and when the intelligent power module is normally powered, the switch is disconnected to avoid electrostatic protection. The influence of the module 302 on the IGBT tube is closed when the intelligent power module stops supplying power, and the electrostatic protection of the IGBT tube by the electrostatic protection module 304 is ensured.

Figure 8 is a block diagram showing the structure of an electrostatic protection device in accordance with one embodiment of the present invention.

As shown in FIG. 8, an electrostatic protection device according to an embodiment of the present invention includes an electrostatic protection module 302 and a state determination module 304. For example, the ESD tolerance circuit shown in FIG. 4 is taken as an example, and the connection relationship between the components is as follows:

One end of the resistor 3401 is connected to VCC, which is the first end of the ESD tolerance boosting circuit 44.

The other end of the resistor 3401 is connected to one end of the resistor 3402, the drain of the NMOS transistor 3407, and the source of the PMOS transistor 3405.

The other end of the resistor 3402 is connected to one end of the resistor 3403 and the drain of the NMOS transistor 3406 and the source of the PMOS transistor 3408.

The other end of the resistor 3403 is connected to UN, and the UN is the second end of the ESD tolerance boosting circuit 44.

The substrate of the PMOS transistor 3405 and the PMOS transistor 3408 is connected to VCC.

The substrate of the NMOS transistor 3406 and the NMOS transistor 3407 is connected to GND (ie, UN).

The drain of the PMOS transistor 3405, the drain of the PMOS transistor 3408, the source of the NMOS transistor 3406, and the source of the NMOS transistor 3407 are connected to the gate of the NMOS transistor 3417.

One end of the resistor 3409 is connected to VCC, and the other end of the resistor 3409 is connected to the drain and gate of the NMOS transistor 3410, the gate of the NMOS transistor 3411, the gate of the NMOS transistor 3415, the gate of the NMOS transistor 3421, and the gate of the NMOS transistor 3423. .

a substrate and a source of the NMOS transistor 3410, a substrate and a source of the NMOS transistor 3411, a substrate and a source of the NMOS transistor 3415, a substrate and a source of the NMOS transistor 3421, and a substrate and a source of the NMOS transistor 3423, The substrate of the NMOS transistor 3426 is connected to the source, the substrate of the NMOS transistor 3201, and the source, and is connected to GND.

The drain of the NMOS transistor 3411 is connected to the drain and gate of the PMOS transistor 3412 and the gate of the PMOS transistor 3413.

The substrate of the PMOS transistor 3412 is connected to the source and the substrate of the PMOS transistor 3413 and the source is connected to the VCC.

The drain of the PMOS transistor 3413 is connected to the gate of the NMOS transistor 3416, the cathode of the Zener diode 3414, and the anode of the Zener diode 3414 is connected to GND.

The substrate of the NMOS transistor 3416 is connected to the source, the substrate of the NMOS transistor 3417, and the drain of the NMOS transistor 3415.

The drain of the NMOS transistor 3417 is connected to the gate of the PMOS transistor 3419 and the drain of the PMOS transistor 3418 to the gate.

The substrate of the PMOS transistor 3419 and the source, the substrate of the PMOS transistor 3418 are connected to the source and connected to VCC.

The drain of the PMOS transistor 3419 is connected to the gate of the PMOS transistor 3420.

The substrate of the PMOS transistor 3420 is connected to the source and connected to VCC.

The drain of the PMOS transistor 3420 is connected to the drain of the NMOS transistor 3421 and the input terminal of the NOT gate 3422.

The output of the NOT gate 3422 is connected to the gate of the NMOS transistor 3426, the gate of the PMOS transistor 3408, the gate of the NMOS transistor 3407, and the input terminal of the NOT gate 3404.

The output of the NOT gate 3404 is connected to the gate of the PMOS transistor 3405 and the NMOS transistor 3406.

The drain of the NMOS transistor 3423 is connected to the drain and gate of the PMOS transistor 3424 and the gate of the PMOS transistor 3425.

The substrate of the PMOS transistor 3424 is connected to the source and the substrate of the PMOS transistor 3425 to the source and is connected to VCC.

The drain of the PMOS transistor 3425 is connected to the drain of the NMOS transistor 3426, the input of the NOT gate 3428, and one end of the capacitor 3427.

The other end of the capacitor 3427 is connected to GND.

The output of the NOT gate 3428 is connected to the gate of the NMOS transistor 3201.

The drain of the NMOS transistor 3201 is connected to one end of the resistor 3202.

The other end of the resistor 3202 is connected to one end of the capacitor 3203 and serves as a third input and output terminal of the ESD tolerance boosting circuit 44, denoted OUT.

The other end of the capacitor 3203 is connected to GND.

Based on the above specific circuit structure, the voltage at point A in Figure 3 is UA, and the voltage at point B is UB, the specific working principle of the ESD tolerance boosting circuit 44 includes:

1. The intelligent power module 10 (shown in Figure 4) works normally.

The resistor 3409 and the NMOS transistor 3410 form a current source to generate a current, which is mirrored to the NMOS transistor 3411, and is mirrored to the PMOS transistor 3413 through the PMOS transistor 3412, so that a current flows through the Zener diode 3414, and a voltage is formed at the gate of the NMOS transistor 3416. Recorded as VZ; for the regulator tube designed using the general BCD process, VZ is about 6.4V.

Because the intelligent power module 10 works normally, the VCC voltage is 15V, and the resistor 3401, the resistor 3402 and the resistor 3403 are designed with appropriate resistance values, so that UA or UB is greater than VZ; the gate voltage of the NMOS transistor 3417 is larger than the gate of the NMOS transistor 3416. The voltage is such that the gate of the PMOS transistor 3420 is at a high level, the PMOS transistor 3420 is turned off, and the input of the NOT gate 3422 is at a low level.

The output of the NOT gate 3422 is high level, and the output of the NOT gate 3404 is low level, so that the PMOS transistor 3405 and the NMOS transistor 3407 are turned on and the PMOS transistor 3408 and the NMOS transistor 3406 are turned off; that is, the gate of the NMOS transistor 3417 at this time. The voltage is UA.

Because the output of the NOT gate 3422 is high, the NMOS transistor 3426 is turned on to make the input of the NOT gate 3428 low, the output of the NOT gate 3428 is high, and the NMOS transistor 3201 is saturated, equivalent to the resistor 3202. One end is connected to the other end of GND and connected to OUT, and an appropriate resistor value is designed for the resistor 3202, so that OUT has a high resistance characteristic to GND.

2. The intelligent power module 10 stops supplying power.

When the intelligent power module 10 is about to stop working, the VCC is powered off, and its voltage is gradually decreased. For the general BCD process, even if the VCC is reduced to 5V, the resistor 3409 and the NMOS transistor 3410 can form a current source to generate current, at a certain time. VCC drops to 7V. At this time, the current generated by the current source is mirrored to the NMOS transistor 3411, and is mirrored to the PMOS transistor 3413 through the PMOS transistor 3412, so that a current flows through the Zener diode 3414, and an appropriate Zener diode 3414 is designed. The gate forming voltage of the NMOS transistor 3416 is still VZ.

The appropriate resistance is designed for the resistor 3401, the resistor 3402 and the resistor 3403 so that the UA at this time is just smaller than VZ; the gate voltage of the NMOS transistor 3417 is smaller than the gate voltage of the NMOS transistor 3416. Thus, the gate of the PMOS transistor 3420 is at a low level, the PMOS transistor 3420 is turned on, and the input of the NOT gate 3422 is at a high level.

The output of the NOT gate 3422 is low level, and the output of the NOT gate 3404 is high level, so that the PMOS transistor 3405 and the NMOS transistor 3407 are turned off and the PMOS transistor 3408 and the NMOS transistor 3406 are turned on; that is, the gate of the NMOS transistor 3417 at this time. The voltage changes from UA to UB, which is a smaller voltage than UA.

Because the output of the NOT gate 3422 is low, the NMOS transistor 3426 is turned off to make the input of the NOT gate 3428 high, the output of the NOT gate 3428 is low, and the NMOS transistor 3201 is turned off, equivalent to one end of the resistor 3202. The other end is connected to OUT. Due to the presence of capacitor 3203, OUT is capacitive to GND.

When the VCC continues to drop to the power-off, the NMOS transistor 3201 remains in the off state. Therefore, the ESD tolerance boosting circuit 44 can maintain the capacitance characteristic after the intelligent power module 10 stops operating, which is equivalent to the IGBT tube 24 after the smart power module 10 stops operating. The capacitor is connected in parallel with the gate, and the capacitor 3203 is designed with an appropriate capacitance value, which can greatly improve the ESD resistance of the gate of the IGBT tube 24.

If the drop of VCC is not due to the power failure of the smart power module 10 but the voltage fluctuation of the power supply, it is necessary to wait for the VCC to rise to UB>VZ, and the ESD tolerance boost circuit 44 can restore the high resistance characteristic.

3, the value of key components

UA and UB are designed to avoid the frequent switching of the characteristics of the OUT GND between the capacitive characteristic and the high-resistance characteristic when the VCC voltage is abnormally fluctuating rather than being truly powered off. Consider:

When VCC=7V is designed, the ESD tolerance improving circuit 44 changes from a high resistance characteristic to a capacitance characteristic;

When VCC = 10 V is designed, the ESD tolerance improving circuit 44 changes from a capacitance characteristic to a high resistance characteristic.

Preferably, the ratio of the resistance values of the resistor 3401, the resistor 3402 and the resistor 3403 can be designed to be 3:10:23, and is the same type of resistor, such as a POLY resistor. When the layout is drawn, the orientation of the three POLY resistors should be It is identical to ensure that the resistance of the three resistors is exactly the same due to process variations, thus ensuring that the resistance ratios of the three resistors are the same. which is:

Then, when VCC=7V, UA≈6.4V; when VCC=10V, UB≈6.4V.

The resistance of the resistor 3402 can be taken as 30kΩ, so that the total resistance of the resistor 3401, the resistor 3402 and the resistor 3403 is 360kΩ, and when VCC=15V, 42μA current flows, and the influence on the static power consumption of the smart power module 10 can be neglected. .

According to different BCD processes, the appropriate resistance value is designed for the resistor 3409, and the appropriate width-to-length ratio is designed for the NMOS transistor 3410. The current source current is about 10 μA. For the current common 600V BCD process, the resistance of the resistor 3409 can be used. Designed to be 100 kΩ, the width to length ratio of the NMOS transistor 3410 is designed to be 5 μm / 3 μm.

The size of the NMOS transistor 3411 is the same as that of the NMOS transistor 3410. The size of the PMOS transistor 3413 is the same as that of the PMOS transistor 3412, so that a current of 10 μA flows through the Zener diode 3414. For a general BCD process, the Zener diode has a current of 100 nA to 1 mA. Can maintain a constant voltage.

In order to further reduce the influence of power supply fluctuation on the characteristic switching of the ESD tolerance enhancement circuit 44, a capacitor 3427 is designed to reduce the speed of signal transmission. According to the voltage fluctuation of the power supply, the capacitance of the capacitor 3427 can be designed to be 1pF to 100pF. In this way, the ESD tolerance enhancement circuit 44 can ensure a rapid response speed and a certain filtering effect on the fluctuation of the power supply.

The resistance of the resistor 3202 can be designed to be 1 MΩ or more, ensuring that the resistance characteristic of the ESD withstand enhancement circuit 44 is such that the gate voltage applied to the IGBT tube 24 is as large as possible, and the influence on the switching speed of the IGBT tube 24 is as small as possible.

The larger the capacitance of the capacitor 3203, the more obvious the enhancement of ESD tolerance. Considering that the ESD tolerance of general consumer electronics is ±2000V, and the space and cost can be saved, the capacitance of the capacitor 3203 can be designed to be 22nF or 47nF.

In addition, in addition to the smart power module shown in FIG. 4, FIG. 5, etc., the present invention also provides an intelligent power module (not shown) including the electrostatic protection device according to any of the above; The invention also proposes a variable frequency home appliance (not shown) comprising the intelligent power module of any of the above.

The technical solution of the present invention is described in detail above with reference to the accompanying drawings. In view of the related art, the intelligent power module is susceptible to electrostatic shock. Therefore, the present invention provides an electrostatic protection device, an intelligent power module and a frequency conversion. The home appliance can avoid the damage of the IGBT tube caused by the high-voltage static electricity of the grounding terminal when the intelligent power module is powered off, ensuring the safety of the intelligent power module and prolonging its service life.

Way two

The difference between the method and the first method is that the method protects the IGBT by disconnecting the connection between the gate of the IGBT tube and the corresponding port on the driving chip when the power supply of the driving chip stops supplying power, as follows:

Embodiment 1

9A is a circuit diagram showing the electrostatic protection device for an IGBT tube of an upper bridge arm according to an embodiment of the present invention.

As shown in FIG. 9A, the electrostatic protection device includes: a state judging module 202 connected to the smart power module for determining a power supply state of the smart power module; and a connection control module 204 connected to the state judging module 202. When the state determining module 202 determines that the power supply condition is to stop power supply, disconnecting the gate of any one of the smart power modules from the driver chip in the smart power module Connection at the output, as well as in the When the state determining module 202 determines that the power supply condition is normal power supply, the connection between the gate of the IGBT tube and the corresponding output terminal on the driving chip is restored.

For convenience of explanation, in the technical solution shown in FIG. 9A, the connection control module 204 is connected to the upper bridge IGBT tube (ie, the IGBT 121 shown in FIG. 1) in the U-phase line. Specifically, the connection control module 204 is connected to the gate of the upper bridge IGBT tube.

9B is a circuit diagram showing the electrostatic protection device for an IGBT tube of a lower arm according to an embodiment of the present invention.

As shown in FIG. 9B, similarly, for the lower bridge IGBT tube in the smart power module, the static protection device may further include: a state determination module 202 connected to the smart power module for determining the smart power module The power supply condition; the connection control module 204 is connected to the state determination module 202, and configured to disconnect the smart power module when the state determination module 202 determines that the power supply condition is to stop power supply. a connection between a gate of any IGBT tube and a corresponding output terminal of the driving chip in the smart power module, and in a case where the state determining module 202 determines that the power supply condition is normal power supply, recovering any of the A connection of a gate of the IGBT transistor to a corresponding output terminal of the driver chip.

For convenience of explanation, in the technical solution shown in FIG. 9B, the connection control module 204 is connected to the lower bridge IGBT tube (ie, the IGBT 124 shown in FIG. 1) in the U-phase line. Specifically, the connection control module 204 is connected to the gate of the lower arm IGBT tube.

In the circuit connection structure of the upper arm and the lower arm respectively shown in FIG. 9A and FIG. 9B, as a specific circuit structure and connection manner, the state judging module 202 may specifically include:

Wherein, corresponding to the case shown in FIG. 9A, since the upper bridge arm IGBT tube is located in the high voltage region, the ground end thereof is opposite ground, that is, not 0V, and may even be "high voltage" with respect to the low voltage region, and The power supply terminal is also the "high voltage" side with respect to the "low voltage" side ground terminal. Therefore, the first end, that is, the end point A1, is connected to the UVB end, and the second end, that is, the end point B1, is connected to the UVS end.

Corresponding to the case shown in FIG. 9B, since the lower arm IGBT tube is located in the low voltage region, its ground terminal is theoretically 0V, and the power supply terminal is opposite to the "high voltage" side of the "low voltage" side ground terminal, although The "high voltage" side may be lower than the ground terminal voltage of the upper bridge IGBT tube. Therefore, the first terminal, that is, the terminal A2, is connected to the power supply VDD of the driving circuit 101, and the second terminal, that is, the terminal B2, is connected to the UN terminal.

As a specific detection method of the power supply state, the detection of the opposite power supply terminal and the ground terminal of an IGBT tube shown in FIG. 9A and FIG. 9B can quickly react to the voltage change on the line, thereby quickly determining The current power supply situation is taken to avoid the IGBT tube being damaged by high voltage static electricity when the power is turned off.

Of course, for the smart power module 100 shown in FIG. 1, the three IGBT tubes of the upper arm, that is, the IGBT tube 121, the IGBT tube 122, and the IGBT tube 123, are connected to the power source and the collector. The emitter is connected to the motor 200, so it is relatively less affected by static electricity.

For the three IGBT tubes of the lower arm, namely the IGBT tube 124, the IGBT tube 125 and the IGBT tube 126, although the collector is also connected to the motor 200, the emitter is connected to the ISO terminal, and the ISO terminal is a small signal connected to the MCU. Relatively more susceptible to the impact of static electricity.

Therefore, for the smart power module 100, any one or more IGBT tubes can be electrostatically protected to minimize the probability of the smart power module 100 being damaged by static electricity; or, due to cost and structural complexity considerations It is also possible to perform electrostatic protection only on one or more IGBT tubes of the lower arm, and also to prevent the intelligent power module 100 from being damaged by static electricity to a large extent.

Fig. 10 is a view showing a device connection structure of an electrostatic protection device according to an embodiment of the present invention.

As shown in FIG. 10, in the electrostatic protection device 40 according to an embodiment of the present invention, the specific device connection status of the state determination module 202 and the connection control module 204 is taken as an example of the lower bridge IGBT tube shown in FIG. 2B. Detailed instructions are given.

1. State determination module 202

Since the IGBT tube of the lower arm is in the low voltage region, in the electrostatic protection device 40, the port VV can be connected to the power supply terminal VCC of the control circuit 1000 as shown in FIG. 1, which is equivalent to the port A2 shown in FIG. 2B. As the power supply end of the electrostatic protection device 40, the port GG can be connected to the ground GND of the control circuit 1000, that is, the port B2 shown in FIG. 2B, as the ground end of the electrostatic protection device 40.

The resistor 401 and the resistor 402 are sequentially connected in series between the port VV and the port GG, and after being divided by the power supply voltage, input to the positive input terminal of the comparator 408. Meanwhile, as a reference voltage for voltage comparison, the voltage source 407 is connected to the comparator 408. The negative input is used to input the reference voltage.

By accurately selecting the size of the resistor 401, the resistor 402 and the voltage source 407, the input voltage of the positive input terminal of the comparator 408 can be made larger than the input voltage of the negative input terminal when the smart power module 100 is energized, so that the output of the comparator 408 is high. Level; while at the smart power module 100 The power-down causes the input voltage at the positive input of comparator 408 to be less than the input voltage at the negative input, such that comparator 408 outputs a low level.

2. Connection control module 204

As a more specific implementation manner, the connection control module 204 may include: a switching device, the control end of the switching device is connected to the state determining module 202, and the controlled terminal is connected to the gate of any one of the IGBT tubes And the corresponding output end of the driving chip (such as the control circuit 1000 shown in FIG. 1); wherein the control terminal controls the controlled end to be turned on when the power supply condition is normal power supply, And the control end controls the controlled end to be disconnected when the power supply condition is to stop power supply.

Specifically, in the circuit configuration shown in FIG. 10, the connection control module 204 may be an optical coupler 411 including a light emitting member and a light receiving member. The illuminating member is the control terminal, which is connected to the state judging module 202, specifically the output end of the comparator 408; the light receiving member is the controlled end, one end of which is connected to the gate of the IGBT tube to be protected through the port G1, and the other end passes The port D1 is connected to a signal output on the control circuit 1000 corresponding to the IGBT tube to be protected, such as when the port G1 is connected to the IGBT tube 124, the port D1 can be connected to the port LO1 of the control circuit 1000.

Based on the above connection structure, when the comparator 408 outputs a high level, the light-emitting member of the photocoupler 411 is driven to emit light, so that the light-receiving member is turned on, so that the port G1 and the port D1 are connected, that is, the IGBT tube 124 is connected to the control circuit 1000. On the upper port LO1; when the comparator 408 outputs a low level, the light-emitting member of the optical coupler 411 stops emitting light, so that the light-receiving member is in a non-conducting state, so that the port G1 and the port D1 are disconnected, that is, the IGBT tube 124 and the control circuit The port LO1 on 1000 is disconnected, which can prevent electrostatic charges from affecting the IGBT tube 124.

In the first embodiment described above, based on the judgment of the power supply status of the smart power module 100, the connection of the gate of the IGBT tube is performed; however, if the power of the intelligent power module 100 is turned on, if the circuit does not enter the working state, There may still be residual electrostatic charge in the circuit, which may have a certain degree of influence on the IGBT tube.

Therefore, the following will be combined with the second embodiment of the second method, how to avoid static electricity remaining in the circuit The effect of charge on the IGBT tube is described in detail.

Embodiment 2

Still taking the embodiment corresponding to that shown in FIG. 9B as an example, that is, the U-phase lower arm IGBT tube 124 of the smart power module 100 (shown in FIG. 1), FIG. 11 illustrates another embodiment in accordance with the present invention. Schematic diagram of the circuit structure of the electrostatic protection device for the IGBT tube of the lower arm.

As shown in FIG. 11, an electrostatic protection device for an IGBT tube of a lower arm according to another embodiment of the present invention includes:

The state judging module 202 is connected to the smart power module for determining the power supply status of the smart power module, and the level sampling module 206 is connected to the corresponding output end of the IGBT tube on the driving chip. An input terminal corresponding to the output terminal on the driving chip is configured to sample a logic level state of a driving signal corresponding to the IGBT tube. The connection control module 204 is coupled to the state determination module 202 and the level sampling module 206 for:

Recovering the connection between the gate of any one of the IGBT tubes and the corresponding output terminal on the driving chip in a case where the logic level state is a high level and the power supply condition is a normal power supply; In the case, if the logic level state is low level or the power supply condition is to stop power supply, the gate of any one of the IGBT tubes in the smart power module is disconnected from the corresponding driver chip in the smart power module. The connection at the output.

Corresponding to the electrostatic protection device proposed in Fig. 11, Fig. 12 is a view showing the device connection structure of the electrostatic protection device according to another embodiment of the present invention.

As shown in FIG. 12, in the electrostatic protection device 40 according to an embodiment of the present invention, the state control module 202, the connection control module 204, and the lower bridge IGBT tube shown in FIG. 4 are taken as an example. The specific device connection of the level sampling module 206 will be described in detail.

1. State determination module 202

Since the IGBT tube of the lower arm is in the low voltage region, in the electrostatic protection device 40, the port VV can be connected to the power supply terminal VCC of the control circuit 1000 as shown in FIG. 1, which is equivalent to the port A2 shown in FIG. 2B. The port GG can be connected to the ground terminal GND of the control circuit 1000, that is, the port B2 shown in FIG. 9B, as the ground terminal of the electrostatic protection device 40.

By accurately selecting the size of the resistor 401, the resistor 402 and the voltage source 407, the input voltage of the positive input terminal of the comparator 408 can be made larger than the input voltage of the negative input terminal when the smart power module 100 is energized, so that the output of the comparator 408 is high. The level is; when the smart power module 100 is powered down, the input voltage of the positive input terminal of the comparator 408 is made smaller than the input voltage of the negative input terminal, so that the comparator 408 outputs a low level.

2. Level sampling module 206

One end of the level sampling module 206 is connected to the connection control module 204, and the other end (ie, the port E1) is connected to the IGBT tube (such as the IGBT tube 124 described above) that needs to be protected, corresponding to the driving chip (such as the above-mentioned control circuit 1000). An output or an input on the driver chip corresponding to the output.

For example, in the case of electrostatic protection of the IGBT tube 124 shown in FIG. 1, the port E1 should be connected to the signal output port LO1 of the control circuit 1000 corresponding to the IGBT tube 124, or to the input port LIN1 corresponding to the port LO1. Among them, when the connection to the input port LIN1 is selected, it helps to increase the reaction speed of the electrostatic protection device 40.

Further, the level sampling module 206 may further include a serially connected NOT gate 403 and a NOT gate 404, thereby facilitating shaping of the driving signal input to the IGBT tube to eliminate interference.

3. Connection control module 204

As a more specific implementation manner, the connection control module 204 can include:

1) a flip-flop 410, the flip-flop 410 includes a reset terminal connected to the state determining module 202 for acquiring the power supply condition; and a set terminal connected to the level sampling module 206 for Obtaining a logic level state corresponding to a driving signal of any one of the IGBT tubes; and outputting a recovery signal when the logic level state is a high level and the power supply condition is a normal power supply, otherwise Output disconnect signal.

As a specific implementation manner, the flip-flop 410 shown in FIG. 12 is an RS flip-flop, and the reset terminal is the R terminal, the set terminal is the S terminal, and the output terminal is the Q terminal. Wherein, the Q terminal outputs a low level in an initial state, that is, an off signal; when the R terminal is reset at a high level, a NOT gate 409 is added between the output end of the comparator 408 and the R terminal, so that When the positive input voltage of the 408 is lower than the negative input voltage (ie, the smart power module is powered down), a high level is input to the R terminal to set the RS flip-flop.

Based on the triggering rule of the RS flip-flop, when the high level is input to the R terminal, regardless of the level of the S terminal, the Q terminal always outputs a low level, that is, the signal is turned off; and when the R terminal inputs a low level, if the S is low, When the input is high, the Q terminal will output a high level, that is, the signal will be restored.

2) a switching device, wherein a control end of the switching device is connected to an output end of the flip-flop 410, and a controlled end is connected between a gate of the any IGBT tube and a corresponding output end of the driving chip; The control end controls the controlled end to be turned on according to the recovery signal, or controls the controlled end to be disconnected according to the disconnection signal.

Specifically, in the circuit configuration shown in FIG. 12, the switching device may be an optical coupler 411 including a light emitting member and a light receiving member. The light-emitting member is a control end connected to the output end of the flip-flop 410; the light-receiving member is a controlled end, one end of which is connected to the gate of the IGBT tube to be protected through the port G1, and the other end is connected to the control circuit 1000 through the port D1. The signal output terminal corresponding to the IGBT tube to be protected, for example, when the port G1 is connected to the IGBT tube 124, the port D1 can be connected to the port LO1 of the control circuit 1000.

Based on the above connection structure, when the flip-flop 410 outputs a high level, the light-emitting member of the photocoupler 411 is driven to emit light, so that the light-receiving member is turned on, so that the port G1 and the port D1 are connected, that is, the IGBT tube 124 is connected to the control circuit 1000. The upper port LO1; and when the flip-flop 410 outputs a low level, the light-emitting member of the photocoupler 411 stops emitting light, so that the light-receiving member is in a non-conducting state, so that the port G1 and the port D1 are disconnected, that is, the IGBT tube 124 and the control circuit The port LO1 on 1000 is disconnected, which can prevent electrostatic charges from affecting the IGBT tube 124.

In FIG. 10 of the first embodiment and FIG. 12 of the second embodiment, the components of the electrostatic protection corresponding to the single IGBT tube are described; the second embodiment shown in FIG. 12 is taken as an example. The electrostatic protection device 40 corresponding to the entire lower arm of the smart power module will be described in detail with reference to FIG. 13, wherein FIG. 13 is a schematic diagram showing the overall device connection structure of the electrostatic protection device according to an embodiment of the present invention.

First, the circuit structure

As shown in FIG. 13, the structure of the electrostatic protection device 40 according to an embodiment of the present invention includes:

The D1 end is connected to the input end of the NOT gate 403, the output end of the NOT gate 403 is connected to the input end of the NOT gate 404, the output end of the NOT gate 404 is connected to the first contact point of the optocoupler 411, and the E1 end is connected to the NOT gate 405. The input end of the NOT gate 405 is connected to the input end of the NOT gate 406, the output end of the NOT gate 406 is connected to the S input terminal of the RS flip-flop 410; the VV terminal is connected to one end of the resistor 401, and the resistor 401 The other end of the resistor 402 is connected to one end of the resistor 402 and the positive terminal of the voltage comparator 408. The other end of the resistor 402 is connected to the GG terminal.

The positive terminal of the voltage source 407 is connected to the negative terminal of the voltage comparator 408, and the negative terminal of the voltage source 407 is connected to the GG terminal. The output terminal of the voltage comparator 408 is connected to the input terminal of the NOT gate 409. The output terminal of 409 is connected to the R input end of the RS flip-flop 410; the Q output end of the RS flip-flop is connected to the positive input end of the optocoupler 411, and the negative input end of the optocoupler 411 is connected to the GG end; The second contact point of the optocoupler 411 is connected to the G1 terminal.

The D2 terminal is connected to the input end of the NOT gate 503, the output end of the NOT gate 503 is connected to the input end of the NOT gate 504, the output end of the NOT gate 504 is connected to the first contact point of the optocoupler 511; An input end of the gate 505, an output end of the NOT gate 505 is connected to an input end of the NOT gate 506, an output end of the NOT gate 506 is connected to an S input end of the RS flip-flop 510; and a VV end is connected to one end of the resistor 501, The other end of the resistor 501 is connected to one end of the resistor 502 and the positive terminal of the voltage comparator 508, and the other end of the resistor 502 is connected to the GG terminal.

The positive terminal of the voltage source 507 is connected to the negative terminal of the voltage comparator 508, the negative terminal of the voltage source 507 is connected to the GG terminal; the output terminal of the voltage comparator 508 is connected to the input terminal of the NOT gate 509, the NOT gate The output end of the 509 is connected to the R input end of the RS flip-flop 510; the Q output end of the RS flip-flop is connected to the positive input end of the optocoupler 511, and the negative input end of the optocoupler 511 is connected to the GG end; The second contact point of the optocoupler 511 is connected to the G2 terminal.

The D3 terminal is connected to the input end of the NOT gate 603, the output end of the NOT gate 603 is connected to the input end of the NOT gate 604, the output end of the NOT gate 604 is connected to the first contact point of the optocoupler 611, and the E3 terminal is connected to the NOT gate 605. The input end of the NOT gate 605 is connected to the input end of the NOT gate 606, the output end of the NOT gate 606 is connected to the S input terminal of the RS flip-flop 610; the VV terminal is connected to one end of the resistor 601, and the resistor 601 The other end of the resistor 602 is connected to one end of the resistor 602 and the positive terminal of the voltage comparator 608, and the other end of the resistor 602 is connected to the GG terminal.

The positive terminal of the voltage source 607 is connected to the negative terminal of the voltage comparator 608, the negative terminal of the voltage source 607 is connected to the GG terminal; the output terminal of the voltage comparator 608 is connected to the input terminal of the NOT gate 609, the NOT gate The output terminal of 609 is connected to the R input end of the RS flip-flop 610; the Q output end of the RS flip-flop is connected to the positive input end of the optocoupler 611, and the negative input end of the optocoupler 611 is connected to the GG end; The second contact point of the optocoupler 611 is connected to the G3 terminal.

Second, the working principle

The operation of the structure based on the embodiment shown in Fig. 13 will be described below. Among them, since D1, E1 to G1, from D2, E2 to G2, and from D3, E3 to G3, the three sets of circuit structures are completely identical, so the description from D1, E1 to G1 is taken as an example:

1, not powered

When the VV terminal is not powered, the static electricity enhancement circuit 40 (corresponding to the above electrostatic protection) The device does not work, the first contact point and the second contact point of the optocoupler (ie, optical coupler) 411 are disconnected, so D1 and G1 are in an off state; this ensures that the IGBT tube is not powered when the power supply is not powered. The gate is suspended and does not come into contact with other contacts of the circuit to avoid electrostatic shock.

2, start to power on

When the VV terminal voltage starts to rise, the electrostatic enhancement circuit 40 starts to operate. In the initial state, the Q output terminal of the RS flip-flop 411 outputs a low level, so the optocoupler 411 is not turned on, and D1 and G1 remain disconnected. State; the voltage at the VV terminal is divided by the resistor 401 and the resistor 402, and the positive terminal of the voltage comparator 408 obtains a voltage V+.

3. Power-on phase one

When the VV terminal voltage rises below a certain value V _TH , the voltage of V+ is less than the voltage V− of the voltage source, that is, when the positive terminal voltage of the voltage comparator 408 is less than the negative terminal voltage, the voltage comparator The output voltage of 408 is low level, and becomes high after passing through the NOT gate 409, that is, the RS flip-flop 411 is reset, and the Q output terminal of the RS flip-flop 411 is kept at a low level.

4, power on stage two

When the voltage of V+ is greater than the voltage V- of the voltage source, that is, when the positive terminal voltage of the voltage comparator 408 is greater than the negative terminal voltage, the voltage of the output terminal of the voltage comparator 408 changes from a low level to a high level. After the NAND gate 409 passes, the R terminal of the RS flip-flop 411 is at a low level, and if the E1 does not have a high-level signal, the RS flip-flop 411 The S terminal of the set terminal does not obtain a high level signal, and the Q output of the RS flip-flop 411 remains at a low level, and when the first high level of E1 comes, the smart power When the module 10 officially starts working, a high level of E1 passes through the NOT gate 505 and the NOT gate 506 to generate a high level at the set terminal S end of the RS flip-flop 410, thereby causing the RS flip-flop. The Q output of 410 changes from a low level to a high level, causing the optocoupler 411 to be turned on, and the first contact point and the second contact point of the optocoupler 411 generate electrical contact, so that the signal of D1 can be directly transmitted to G1; after the first high level of E1 comes, the voltage of E1 goes back to low level, but due to the holding action of the RS flip-flop 410, the RS touch High Q output 410 is maintained, the retention optocoupler 411 Holding in the on state, the signal of D1 can be continuously transmitted to G1, so that the intelligent power module 10 remains kept in normal operation.

5, power down

When the intelligent power module 10 stops operating, the VV voltage changes from high to low, and when lowered to below _VTH , the V+ voltage is lower than the V-voltage, so that the voltage comparator 408 outputs a low level, after the After the NOT gate 509 becomes a high level, that is, the R terminal of the RS flip-flop 410 is at a high level, the RS flip-flop 410 is reset, and the Q terminal of the RS flip-flop 410 outputs a low level, thereby The optocoupler 411 is turned off, and G2 is again in a floating state without making electrical connection with the remaining points; at this time, since the smart power module 10 is ready to stop working, the power supply is already in a down state, and the E1 end generally does not A high level occurs, but even if E1 appears high level due to noise or the like and is transmitted to the S terminal of the RS flip-flop 510 after being subjected to two filtering by the NOT gate 505 and the NOT gate 506, The holding action of the RS flip-flop 510, when the R terminal and the S terminal are simultaneously at a high level, the Q terminal of the RS flip-flop 510 can still maintain a low level, so that G1 is reliably suspended.

Third, the value of choice

The voltage source 407 can take a value of 3V, that is, V-=3V, and the resistance ratio of the resistor 401 and the resistor 402 can be 1:1.

When VV<6V:

Thus V+<V-, the voltage comparator 408 outputs a low level;

When VV>6V:

Thus V+>V-, the voltage comparator 408 outputs a high level, that is, VTH=6V at this time.

When the smart power module 10 is in normal operation, the VV is generally 15V, which is much larger than 6V, so that the voltage comparator 408 can be reliably outputted with a high level; when the intelligent power module 10 stops working, the VV starts from 15V. Drop, due to the role of the voltage regulator capacitor, etc., it will drop very quickly at the beginning, generally will quickly reach the voltage below 4 ~ 5V, and to reach 0V completely will have a longer tail, because V _{TH is} set to 6V Therefore, the voltage comparator 408 can react at the moment when the VV starts to be powered down, and the G1 quickly enters a floating state.

Of course, for the switching device, there are many ways to select, that is, those skilled in the art can realize the selection of the switching device according to their actual needs. For example, as another more specific embodiment, FIG. 14 is a schematic diagram showing the overall device connection structure of an electrostatic protection device according to another embodiment of the present invention.

As shown in FIG. 14, the optocoupler 411 and the like are replaced with a MOSFET tube 412 and the like, and the specific structure thereof includes:

The output of the NOT gate 404 is connected to the drain of the MOSFET 412, the Q output of the RS flip-flop 410 is connected to the gate of the MOSFET 412, and the substrate of the MOSFET 412 is connected to the source. Connected to G1.

The output of the NOT gate 504 is connected to the drain of the MOSFET 512, the Q output of the RS flip-flop 510 is connected to the gate of the MOSFET 512, and the substrate of the MOSFET 512 is connected to the source. Connected to G2.

The output of the NOT gate 604 is connected to the drain of the MOSFET 612, the Q output of the RS flip-flop 610 is connected to the gate of the MOSFET 612, and the substrate of the MOSFET 612 is connected to the source. Connected to G3.

The MOSFET (ie, MOSFET 412, MOSFET 512, or MOSFET 612) acts as an analog switch here, and the optocoupler (ie, optocoupler 411, optocoupler 511, or optocoupler 611) is similar:

When the gate of the MOSFET is high, the drain and source of the MOSFET are turned on; when the gate of the MOSFET is low, the drain and source of the MOSFET are turned off.

Of course, based on different needs and applications, users can choose to use different switching devices such as optocouplers or MOSFETs; for example, the optocoupler has better conduction and isolation effects, while the cost of MOSFETs is relatively higher.

Taking the second embodiment as an example, FIG. 15 shows a schematic structural diagram of an intelligent power module including an electrostatic protection device according to an embodiment of the present invention.

First, the circuit structure

As shown in FIG. 15, the structure of the smart power module 10 including the electrostatic protection device 40 according to an embodiment of the present invention includes:

The VDD end of the smart power module 10 serves as the power supply positive VV of the low voltage region power supply positive VCC of the control circuit 11, the power supply positive voltage VV of the electrostatic enhancement circuit (corresponding to the above electrostatic protection device) 40, and the VDD of the PMOS transistor 50 is the smart power. Module 10's low-voltage zone power supply, VDD is typically 15V.

The HIN1 end of the control circuit 11 serves as the U-phase upper arm input end UHIN of the intelligent power module 10; the HIN2 end of the control circuit 11 serves as the V-phase upper arm input end VHIN of the intelligent power module 10; The HIN3 end of the control circuit 11 serves as the W-phase upper arm input terminal WHIN of the intelligent power module 10; the LIN1 end of the control circuit 11 is connected to the E1 end of the electrostatic enhancement circuit 40, and serves as the smart The U-phase lower arm input terminal ULIN of the power module 10; the LIN2 end of the control circuit 11 is connected to the E2 end of the electrostatic enhancement circuit 40, and serves as the V-phase lower arm input end VLIN of the intelligent power module 10 The LIN3 end of the control circuit 11 is connected to the E3 end of the electrostatic enhancement circuit 40, and serves as the W-phase lower arm input terminal WLIN of the intelligent power module 10; here, the U of the intelligent power module 10 The six inputs of the three phases of V, W receive 0 to 5V input signals.

The GND end of the control circuit 11 is connected to the power supply negative terminal GG of the static electricity enhancement circuit 40, and serves as the low-voltage power supply negative terminal COM of the intelligent power module 10.

The VB1 end of the control circuit 11 is connected to the source of the PMOS transistor 41 and the substrate, and serves as the U-phase high voltage region power supply positive terminal UVB of the intelligent power module 10; the OUT1 end of the control circuit 11 and the The gate of the PMOS transistor 41 and the gate of the NMOS transistor 42 are connected; the drain of the PMOS transistor 41 is connected to the drain of the NMOS transistor 42 and is referred to as the HO1 terminal, and the HO1 terminal and the U-phase upper arm IGBT tube 21 are connected. The gate of the control circuit 11 is connected to the source and the substrate of the NMOS transistor 42 , the emitter of the IGBT transistor 21 , the anode of the FRD transistor 41 , and the U-phase lower arm IGBT tube 24 . The collector, the cathode of the FRD tube 14 is connected, and serves as the U-phase high voltage region power supply negative terminal U of the intelligent power module 10.

The VB2 end of the control circuit 11 is connected to the source of the PMOS transistor 44 and the substrate, and serves as the V-phase high voltage region power supply positive terminal VVB of the intelligent power module 10; the OUT2 end of the control circuit 11 is The gate of the PMOS transistor 44 and the gate of the NMOS transistor 45 are connected; the drain of the PMOS transistor 44 is connected to the drain of the NMOS transistor 45 and is referred to as the HO2 terminal, and the HO2 terminal and the V-phase upper arm IGBT transistor 22 are connected. The gate of the control circuit 11 is connected to the source and the substrate of the NMOS transistor 45, the emitter of the IGBT transistor 22, the anode of the FRD tube 12, and the U-phase lower arm IGBT tube 25. The collector, the cathode of the FRD tube 15 is connected, and serves as the negative terminal V of the V-phase high voltage region of the intelligent power module 10.

The VB3 end of the control circuit 11 is connected to the source of the PMOS transistor 44 and the substrate, and serves as the V-phase high voltage region power supply positive terminal VVB of the intelligent power module 100; the OUT3 end of the control circuit 11 and the The gate of the PMOS transistor 47 and the gate of the NMOS transistor 48 are connected; the drain of the PMOS transistor 47 is connected to the drain of the NMOS transistor 48 and is referred to as the HO3 terminal, and the HO3 terminal and the W phase upper arm IGBT tube 23 are connected. The gate of the control circuit 11 is connected to the source and the substrate of the NMOS transistor 48, the emitter of the IGBT transistor 23, the anode of the FRD tube 13, and the W-phase lower arm IGBT tube 26. The collector, the cathode of the FRD tube 16 is connected, and serves as the power supply negative terminal W of the W-phase high voltage region of the intelligent power module 10.

The collector of the IGBT tube 21, the collector of the IGBT tube 22, the collector of the IGBT tube 23, the cathode of the FRD tube 11, the cathode of the FRD tube 12, and the cathode of the FRD tube 13 Connected, and as the high voltage input terminal P of the intelligent power module 10, P is generally connected to 300V.

The OUT4 end of the control circuit 11 is connected to the gate of the PMOS transistor 50 and the gate of the NMOS transistor 51; the drain of the PMOS transistor 50 is connected to the drain of the NMOS transistor 51 and is recorded as the LO1 terminal. The LO1 terminal is connected to the D1 terminal of the electrostatic enhancement circuit 40.

The OUT5 end of the control circuit 11 is connected to the gate of the PMOS transistor 53 and the gate of the NMOS transistor 54; the drain of the PMOS transistor 53 is connected to the drain of the NMOS transistor 54 and is recorded as the LO2 terminal. The LO2 terminal is connected to the D2 terminal of the electrostatic enhancement circuit 40.

The OUT6 end of the control circuit 11 is connected to the gate of the PMOS transistor 56 and the gate of the NMOS transistor 57; the drain of the PMOS transistor 56 is connected to the drain of the NMOS transistor 57 and is recorded as the LO3 terminal. The LO3 terminal is connected to the D3 terminal of the electrostatic enhancement circuit 40.

The G1 end of the static electricity enhancement circuit 40 is connected to the gate of the U-phase lower arm IGBT tube 24; the G2 end of the static electricity enhancement circuit 40 is connected to the gate of the V-phase lower arm IGBT tube 25; The G3 end of the electrostatic enhancement circuit 40 is connected to the gate of the W-phase lower arm IGBT tube 26.

a substrate and a source of the NMOS transistor 51, a substrate and a source of the NMOS transistor 54, a substrate and a source of the NMOS transistor 57, and a power supply of a low-voltage region of the smart power module 10 Negative COM.

The emitter of the IGBT tube 24, the emitter of the IGBT tube 25, the emitter of the IGBT tube 26, the anode of the FRD tube 14, the anode of the FRD tube 15, and the anode of the FRD tube 16. Connected to one end of the sampling resistor 33 and used as the current detecting terminal ISO of the intelligent power module 10. The other end of the resistor 33 is connected to the low voltage power supply negative terminal COM of the smart power module 10.

Second, the working principle

1. The function of the control circuit 11 is:

The 0~5V signals of the six input terminals of UHIN, VHIN, WHIN, ULIN, VLIN, and WLIN are received and transmitted to the output terminals HO1, HO2, HO3, and LO1, LO2, and LO3, where HO1, HO2, and HO3 are VS~VS+15V. The logic signals, LO1, LO2, and LO3 are logic signals of 0 to 15V. It functions exactly the same as the control circuit 1000 of the prior art.

2. The function of the electrostatic enhancement circuit 40 is:

1) When the smart power module 10 is not powered, G1, G2, G3 are isolated and not electrically connected to other pins.

2) When the smart power module 10 is powered on, if the high level signals of D1, D2, and D3 are not obtained, G1, G2, and G3 continue to be isolated without being electrically connected to other pins; D2 and D3 respectively appear a first high level, and G1, G2, and G3 respectively generate electrical connections with internal circuits of the static electricity enhancement circuit 40, and respectively output the same electrical signals as D1, D2, and D3;

When the voltage of the low-voltage area power supply VDD of the smart power module 10 is lower than a certain value, G1, G2, and G3 are re-isolated.

The technical solution of the present invention is described in detail above with reference to the accompanying drawings. The present invention provides an electrostatic protection device, an intelligent power module and a frequency conversion home appliance, which can achieve the following technical effects:

When the power supply voltage of the intelligent power module is relatively low or there is no voltage, it indicates that the intelligent power module is in or will enter the stop working state. Because of the function of the static electricity enhancement circuit, the gates of the three IGBT tubes of the lower arm are suspended without intelligent power. Any exposed pins of the module make electrical connections, so external static electricity can not form a voltage impact on the gate oxide of the three IGBT tubes of the lower arm, effectively eliminating static electricity and damaging the three IGBT tubes of the lower arm of the intelligent power module. risks of.

When the power supply voltage of the intelligent power module is relatively high, the intelligent power module is in a normal working state. Because of the function of the static electricity enhancement circuit, G1, G2, and G3 connected to the gates of the three IGBT tubes of the lower arm are generated with LO1 and LO2. The same signal as LO3, normally drives the three IGBT tubes of the lower arm to work.

Because the electrostatic resistance of the IGBT tube when the intelligent power module is in the non-operating state is no longer related to the thickness of the IGBT tube gate oxide, the thickness of the gate oxide of the IGBT tube for the intelligent power module of this structure can be designed to be thin. The gate capacitance of the IGBT tube is very small, the switching speed is very fast, so that the heat generated by the IGBT tube during actual operation is small, the performance and long-term reliability of the intelligent power module are improved, and the life of the intelligent power module is prolonged.

The circuit board of the intelligent power module of such a structure is designed without any consideration of the electrostatic protection of the intelligent power module, which greatly reduces the difficulty and manufacturing cost of the circuit board design, and can ensure the intelligent power module using the structure. The system works in a more hostile environment without damage.

Those skilled in the art can understand all or part of the method carried by the above embodiment. The sub-steps may be performed by a program to instruct related hardware, and the program may be stored in a computer readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiments.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. The integrated modules, if implemented in the form of software functional modules and sold or used as stand-alone products, may also be stored in a computer readable storage medium.

The above mentioned storage medium may be a read only memory, a magnetic disk or an optical disk or the like.

The above description is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can also make several improvements and retouchings without departing from the principles of the present invention. It should be considered as the scope of protection of the present invention.

Claims

An intelligent power module, comprising:

Multiple IGBT tubes;

Driving a plurality of driving tubes of the plurality of IGBT tubes;

Controlling a driving chip of the plurality of IGBT tubes by the plurality of driving tubes;

At least one protection component corresponding to at least one of the plurality of IGBT tubes, the at least one protection component for electrostatically protecting the at least one IGBT tube.
The intelligent power module according to claim 1, wherein the protection component comprises an electrostatic protection module for absorbing static electricity of the at least one IGBT tube.
The intelligent power module according to claim 2, wherein the protection component further comprises:

a state judging module is connected to the driving chip, and is configured to determine a power supply state of the driving chip;

The static electricity protection module is further connected to the state determination module, configured to perform electrostatic protection on the at least one IGBT tube when the state determination module determines that the power supply of the driving chip stops power supply.
The intelligent power module according to claim 3, wherein the state determining module comprises:

a first end, connected to a corresponding power supply end of the at least one IGBT tube, detecting a supply voltage corresponding to the IGBT tube;

a second end, connected to a ground end corresponding to the at least one IGBT tube, detecting a ground voltage corresponding to the at least one IGBT tube;

a voltage comparison circuit is connected to the first end and the second end, and when the voltage difference between the power supply voltage and the ground voltage is greater than or equal to a preset voltage value, determining that the power supply state is a normal power supply Determining the power supply state when the voltage difference is less than the preset voltage value To stop powering.
The intelligent power module according to claim 4, wherein when the at least one IGBT tube is an upper arm of any phase, the power supply end of the at least one IGBT tube is a high voltage of the any phase a positive end of the power supply of the area, the corresponding ground end of the at least one IGBT tube is a power supply negative end of the high voltage region of the any phase, when the at least one IGBT tube is the lower arm of the any phase The power supply end corresponding to the at least one IGBT tube is a power supply power positive end of the low voltage area of the smart power module, and the corresponding ground end of the at least one IGBT tube is a power supply power negative end of the low voltage area of the smart power module. .
The intelligent power module according to claim 3, wherein the electrostatic protection module is configured to:

Switching and presenting corresponding circuit characteristics according to the power supply condition of the driving chip,

The electrostatic protection module exhibits a high-resistance characteristic when the power supply of the driving chip is normally powered. When the power supply of the driving chip stops supplying power, the electrostatic protection module exhibits a capacitive characteristic.
The intelligent power module according to claim 6, wherein the electrostatic protection module comprises:

a resistor and a capacitor, one end of the resistor and the anode of the capacitor are connected in parallel to the gate of the at least one IGBT tube, and the cathode of the capacitor is connected to a corresponding ground end of the at least one IGBT tube;

a switching device, a first end of the switching device is connected to the state judging module, a second end is connected to the other end of the resistor, and a third end is connected to a ground end corresponding to the at least one IGBT tube;

Wherein the switching device closes the connection of the resistor to the ground end corresponding to the at least one IGBT tube when the power supply of the driving chip is normally powered, and disconnects the power when the power of the driving chip stops supplying power A connection of a resistor to a ground end corresponding to the at least one IGBT tube.
The intelligent power module according to claim 7, wherein the switching device comprises:

And a switch tube that saturates on when the power supply of the driving chip is normally powered, and is turned off when the power of the driving chip stops supplying power.
The intelligent power module according to claim 1, wherein the protection component comprises:

a state judging module is connected to the driving chip, and is configured to determine a power supply state of the driving chip;

a connection control module, connected to the state determination module, configured to disconnect the gate of the at least one IGBT tube in the driving chip if the state determining module determines that the power supply condition is to stop power supply a connection with a corresponding output terminal on the driving chip, and in a case where the state determining module determines that the power supply condition is normal power supply, recovering a gate of the at least one IGBT tube and a corresponding one on the driving chip The connection at the output.
The intelligent power module according to claim 9, wherein the state determining module comprises:

a first end, connected to a corresponding power supply end of the at least one IGBT tube, detecting a supply voltage corresponding to the at least one IGBT tube;

a second end, connected to a ground end corresponding to the at least one IGBT tube, detecting a ground voltage corresponding to the at least one IGBT tube;

a voltage comparison circuit is connected to the first end and the second end, and when the voltage difference between the power supply voltage and the ground voltage is greater than or equal to a preset voltage value, determining that the power supply state is a normal power supply When the voltage difference is less than the preset voltage value, determining that the power supply condition is to stop power supply.
The intelligent power module according to claim 10, wherein when the at least one IGBT transistor is a lower arm of any phase, the corresponding power supply terminal of the at least one IGBT transistor is a power input of the driving chip The ground end corresponding to the at least one IGBT tube is a ground end of the driving chip.
The intelligent power module according to any one of claims 9 to 11, wherein the connection control module comprises:

a switching device, the control end of the switching device is connected to the state judging module, and the controlled end is connected Connected between a gate of the at least one IGBT tube and a corresponding output end of the driving chip;

The control end controls the controlled end to be turned on when the power supply condition is normal power supply, and the control end controls the controlled end to disconnect when the power supply condition is to stop power supply. .
The intelligent power module according to any one of claims 9 to 11, further comprising:

a level sampling module connected to the corresponding output end of the at least one IGBT transistor on the driving chip or an input end of the driving chip corresponding to the output end for sampling corresponding to the at least one IGBT tube The logic level state of the drive signal;

Wherein the connection control module is further connected to the level sampling module, and recovering the at least one IGBT tube if the logic level state is a high level and the power supply condition is a normal power supply A connection of the gate to a corresponding output on the driver chip.
The intelligent power module according to claim 13, wherein the connection control module comprises:

a trigger, the trigger comprising:

a reset end, connected to the state determining module, configured to acquire the power supply status;

a set end connected to the level sampling module for acquiring a logic level state of a driving signal corresponding to the at least one IGBT tube;

Outputting, when the logic level state is high level and the power supply condition is normal power supply, outputting a recovery signal, otherwise outputting an off signal;

a switching device, a control end of the switching device is connected to an output end of the flip-flop, and a controlled end is connected between a gate of the at least one IGBT tube and a corresponding output end of the driving chip;

The control end controls the controlled end to be turned on according to the recovery signal, or controls the controlled end to be disconnected according to the disconnection signal.
The intelligent power module according to claim 14, wherein the switching device comprises:

a switch tube, the drive end of the switch tube is the control end, and the output end and the input end of the switch tube are the controlled end;

The recovery signal is a high level signal for controlling conduction between the output end and the input end of the switch tube; the disconnection signal is a low level signal for controlling the output of the switch tube The end is cut off between the terminal and the input.
The intelligent power module according to claim 14, wherein the switching device comprises:

An optical coupler, wherein the light-emitting member of the optical coupler is the control end, and the light-receiving member is the controlled end;

Wherein the illuminating member emits light when receiving the recovery signal to control the light-receiving member to be turned on; and does not emit light when receiving the disconnecting signal to control the light-receiving member to be disconnected.
A variable frequency home appliance, comprising the intelligent power module according to any one of claims 1-16.
An electrostatic protection device, comprising:

The electrostatic protection module is connected to any IGBT tube in the smart power module for electrostatically protecting any one of the IGBT tubes.
An electrostatic protection device, comprising:

a state judging module is connected to the smart power module, and is configured to determine a power supply state of the smart power module;

a connection control module, connected to the state determination module, configured to disconnect the gate of any one of the IGBT tubes in the smart power module if the state determination module determines that the power supply condition is to stop power supply Reconnecting a corresponding output end of the driving chip in the smart power module, and recovering the gate of the IGBT tube and the driving in a case where the state determining module determines that the power supply condition is normal power supply The connection of the corresponding output on the chip.