Power semiconductor module and service life detection method thereof and inverter device

Abstract

The present invention provides a power semiconductor module and a life detection method thereof and an inverter device, comprising: a power semiconductor device; a saturation voltage drop detection unit, electrically connected to the power semiconductor device, for detecting the saturation voltage drop V of the power semiconductor device. CESAT and a life prompt unit connected to the saturation voltage drop detection unit, and capable of detecting the saturation voltage drop V according to the saturation voltage drop V CESAT A prompt message is issued, and the prompt message indicates the service life of the power semiconductor device. Since the main reason affecting the service life of the power semiconductor device is the connection degradation of the material joint of the power semiconductor device, it generally occurs at the joint of the binding wire and the chip, the solder layer of the chip and the DBC insulating substrate, and the solder layer of the DBC insulating substrate and the copper bottom plate. The connection degradation (loosening or peeling) of the above three places will lead to an increase in the resistance of the connection, which will lead to a saturation voltage drop V CESAT The increase of saturation voltage V CESAT Detection and calculation of the service life of power semiconductor devices.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor power device packaging, and more particularly to a power semiconductor module and a service life detection method thereof and an inverter device. Background Art

[0002] Power semiconductor devices are mainly used for high-power electronic devices (usually referring to currents of tens to thousands of amperes and voltages of hundreds of volts or more) in power equipment power conversion and control circuits. Due to the differences in the coefficient of thermal expansion (CTE) of the various components of power semiconductors, long-term operation under cyclic load changes or frequent drastic load changes may cause material joint connection degradation. This degradation generally occurs at the junction of the binding wire and the chip, the solder layer of the chip and the DBC insulating substrate, and the solder layer of the DBC insulating substrate and the copper base plate. The connection degradation of the material joint has also become the main factor affecting the life of the power semiconductor module. The main reason is that the existing inverter devices basically only collect typical operating conditions in the design stage to calculate or measure the junction temperature change amplitude and the number of cycles, and estimate the life by comparing the typical power cycle life curve given by the device manufacturer. Since the power cycle life curve given by the manufacturer is only an experimental value under specific conditions, it is quite different from the actual operating conditions of the customer, and the experimental samples are very small, the power cycle life estimated according to this curve is very low in accuracy. It is possible that the module is damaged before the estimated life, resulting in abnormal shutdown, or the module is replaced before the module life, resulting in unnecessary waste.

[0003] Therefore, it is necessary to improve the existing power semiconductor modules. Summary of the invention

[0004] In view of the problem that the module life of the power semiconductor module in the prior art is difficult to accurately predict, the present invention provides a power semiconductor module, comprising: a power semiconductor device; a saturation voltage drop detection unit, electrically connected to the power semiconductor device, for detecting the saturation voltage drop V of the power semiconductor device. CESAT and a life prompt unit connected to the saturation voltage drop detection unit, and capable of detecting the saturation voltage drop V according to the saturation voltage drop V CESAT A prompt message is issued, wherein the prompt message indicates the service life of the power semiconductor device.

[0005] The main reason affecting the life of power semiconductor devices is the degradation of the connection of the power semiconductor device material joints, which generally occurs at the junction of the bonding wire and the chip, the solder layer of the chip and the DBC insulating substrate, and the solder layer of the DBC insulating substrate and the copper base plate. The connection degradation (loosening or peeling) at the above three places will lead to an increase in the resistance of the connection, which will lead to a saturation voltage drop V CESATThe increase in the saturation voltage drop V CESAT Detection and calculation of the service life of power semiconductor devices.

[0006] Although when a power semiconductor device is purchased, the manufacturer will provide a typical power cycle life curve for the user to calculate the service life of the power semiconductor device, the power cycle life curve provided by the manufacturer is only an experimental value under specific conditions and is quite different from the actual operating conditions of the user. The service life information of the power semiconductor device provided by the present invention is closer to the actual application conditions of the power semiconductor device than the power cycle life curve provided by the manufacturer, thereby improving the accuracy of the service life estimation of the power semiconductor device and avoiding abnormal shutdown caused by damage of the power semiconductor device before the estimated service life and unnecessary waste caused by replacing the power semiconductor device before the estimated service life.

[0007] In a preferred technical solution of the present invention, the life prompt unit includes: a voltage drop comparison unit, which is electrically connected to the saturation voltage drop detection unit, and compares the saturation voltage drop V detected by the saturation voltage drop detection unit. CESAT With saturation voltage drop threshold V CESAT(TH) Make a comparison.

[0008] In a preferred technical solution of the present invention, the life prompt unit further includes: an alarm unit connected to the output end of the voltage drop comparison unit to CESAT >V CESAT(TH) Send an alarm signal when

[0009] In this technical solution, since V CESAT >V CESAT(TH) When the power semiconductor device is operating in an overcurrent state, and it is very likely to cause damage to the power semiconductor device, timely alarm can enable the user to discover and solve the problem in time to reduce the loss caused by sudden downtime of the equipment using the power semiconductor device due to failure of the power semiconductor device.

[0010] In a preferred technical solution of the present invention, the life prompt unit further includes: a storage unit, electrically connected to the saturation voltage drop detection unit, for storing the saturation voltage drop V detected by the saturation voltage drop detection unit. CESAT Historical data.

[0011] In this technical solution, the storage unit can store the saturation voltage drop V detected by the saturation voltage drop detection unit. CESAT The user can download the data regularly and analyze the service life of the power semiconductor device based on the data. Specifically, the user can analyze the service life of the power semiconductor device based on the saturation voltage drop V CESAT The historical data plots the saturation voltage drop V CESATThe corresponding growth curve with time changes (theoretically, as the power semiconductor device works for a long time under the condition of cyclic load changes, the saturation voltage drop V CESAT will continue to increase), and the saturation voltage drop V CESAT The maximum value is related to the maximum saturation voltage drop V of the power semiconductor device CESAT(TH) Compare and calculate the saturation voltage drop V accordingly CESAT Increase to the maximum saturation voltage drop V CESAT(TH) The time is the service life of the power semiconductor device. The user can judge whether the power semiconductor device needs to be replaced according to the service life of the power semiconductor device. With this arrangement, the service life of the power semiconductor device can be monitored. In particular, when there are multiple power semiconductor devices in the device, multiple power semiconductor devices 1 can be connected to the storage unit at the same time to realize simultaneous monitoring of multiple power semiconductor devices.

[0012] In a preferred technical solution of the present invention, it also includes: a current detection circuit, which is electrically connected to the saturation voltage drop detection unit and the output end of the power semiconductor device, respectively. In response to the current detection circuit detecting that the current at the output end of the power semiconductor device reaches a threshold value, the saturation voltage drop detection unit detects the current saturation voltage drop V of the power semiconductor device. CESAT .

[0013] In this technical solution, when the current at the output end of the power semiconductor device reaches a certain threshold, it is determined that the device having the power semiconductor device is in operation. Under this condition, the saturation voltage drop detection unit is started to detect the current saturation voltage drop of the power semiconductor device, which can save energy and avoid detecting invalid data.

[0014] In a preferred technical solution of the present invention, the saturation voltage drop detection unit includes: a saturation voltage drop detection circuit, electrically connected to the power semiconductor device; a sampling circuit, electrically connected to the saturation voltage drop detection circuit to detect the saturation voltage drop V CESAT Sampling; shielding time setting circuit, electrically connected to the sampling circuit, so that the sampling circuit starts sampling after a preset time T, to ensure that the power semiconductor device operates in a saturation region when the sampling circuit performs sampling.

[0015] In a preferred technical solution of the present invention, the saturation voltage drop detection circuit includes: a resistor R, a diode D and a zener diode ZD connected in series between the collector and the emitter of the power semiconductor device, wherein one end of the resistor R is connected to the collector, and the other end is connected to the positive electrode of the diode D, the negative electrode of the zener diode ZD is connected to the negative electrode of the diode D, and the positive electrode of the zener diode ZD is connected to the emitter.

[0016] In a preferred technical solution of the present invention, two input terminals of the sampling circuit are respectively connected to the anode of the diode D and the anode of the voltage stabilizing diode ZD.

[0017] Taking the power semiconductor device IGBT as an example, the IGBT chip is initially in the off state, and the voltage applied to both ends of the IGBT chip forms a loop through the resistor R, the diode D and the Zener diode ZD. The current in the loop is limited by the resistor R. The sampling circuit collects the voltage value across the Zener diode ZD at this time. When the power supply applies a voltage of a predetermined amplitude and pulse width to the gate of the IGBT chip, when it enters a stable state, the voltage drop between the collector and emitter of the IGBT chip becomes a saturation voltage drop V CESAT At this time, the IGBT chip and the load at the output end form a loop, and no current flows through the resistor R, diode D, and Zener diode ZD. The voltage collected by the sampling circuit is the saturation voltage drop V CESAT .

[0018] In a preferred technical solution of the present invention, the sampling circuit is an isolated analog-to-digital conversion circuit.

[0019] In this technical solution, the sampling circuit adopts an isolated analog-to-digital conversion circuit. In some alternative technical solutions, the sampling circuit can also be an oscilloscope or other devices that can collect voltage information.

[0020] In a preferred technical solution of the present invention, the power semiconductor device is an insulated gate bipolar transistor (IGBT).

[0021] In this technical solution, the power semiconductor device is an insulated gate bipolar transistor (IGBT), which is only used as an example. The technical solution provided by the present invention can also be used to calculate the service life of other types of power semiconductor devices.

[0022] In order to achieve the above-mentioned purpose of the invention, the present invention provides a method for detecting the service life of a power semiconductor module, which is used to detect the service life of the above-mentioned power semiconductor module. The service life detection method comprises the steps of: obtaining a saturation voltage drop V CESAT ; According to the saturation voltage drop V of the power semiconductor device CESAT Calculate the service life of power semiconductor devices.

[0023] In order to achieve the above-mentioned object of the invention, the present invention provides an inverter device, comprising the above-mentioned power semiconductor module. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of a semiconductor power module in a preferred technical solution of the present invention;

[0025] Figure 2 yes Figure 1 Partial wiring diagram of semiconductor power module;

[0026] Figure 3 yes Figure 1 Circuit diagram of saturation voltage drop detection circuit of semiconductor power module;

[0027] Figure 4 It is the current-voltage-time curve of the IGBT chip;

[0028] Figure 5 This is the current-voltage-time curve of the FWD chip.

[0029] Description of the drawings: 100-power semiconductor module; 1-power semiconductor device, 11-IGBT chip, 12-FWD chip; 2-saturation voltage drop detection unit, 21-saturation voltage drop detection circuit, 22-sampling circuit, 23-shielding time setting circuit; 3-life reminder unit; 4-voltage drop comparison unit; 5-alarm unit; 6-storage unit; 7-current detection circuit; R-resistor; D-diode; ZD-voltage regulator diode.

[0030] Specific technical solutions

[0031] The preferred technical solutions of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these technical solutions are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make adjustments to them as needed to adapt to specific application scenarios.

[0032] It should be noted that, in the description of the preferred embodiments of the present invention, terms such as "up", "down", "left", "right", "front", "back", "vertical", "horizontal", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or component must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation on the present invention.

[0033] The main reason affecting the life of the power semiconductor device 1 is the degradation of the connection of the material joint of the power semiconductor device 1, which generally occurs at the joint between the bonding wire and the chip, the solder layer between the chip and the DBC insulating substrate, and the solder layer between the DBC insulating substrate and the copper base plate. The connection degradation (loosening or peeling) at the above three places will lead to an increase in the resistance of the connection, which will lead to a saturation voltage drop V CESAT The increase in the saturation voltage drop V CESAT The service life of the power semiconductor device 1 is calculated by detection.

[0034] Specifically, Figure 1 and Figure 2 As shown, this embodiment provides a power semiconductor module 100, which at least includes: a power semiconductor device 1; a saturation voltage drop detection unit 2; and a life prompt unit 3; wherein the saturation voltage drop detection unit 2 is electrically connected to the power semiconductor device 1 and can detect the saturation voltage drop V CESAT The life prompt unit 3 is connected to the saturation voltage drop detection unit 2 and can detect the saturation voltage drop V CESAT A prompt message is issued, which indicates the service life of the power semiconductor device 1 .

[0035] Although the manufacturer will provide a typical power cycle life curve for the user to calculate the service life of the power semiconductor device 1 when the power semiconductor device 1 is purchased, the power cycle life curve provided by the manufacturer is only an experimental value under specific conditions and is quite different from the actual operating conditions of the user. The service life information of the power semiconductor device 1 provided in this embodiment is closer to the actual application conditions of the power semiconductor device than the power cycle life curve provided by the manufacturer, thereby improving the accuracy of the service life estimation of the power semiconductor device and avoiding abnormal shutdown caused by damage of the power semiconductor device before the estimated service life and unnecessary waste caused by replacing the power semiconductor device before the estimated service life.

[0036] Among them, the power semiconductor device 1 is also called a power electronic device (Power Electronic Device), which is mainly used for high-power electronic devices (usually referring to currents of tens to thousands of amperes and voltages of hundreds of volts or more) in the power conversion and control circuits of power equipment. There are many types of power semiconductor devices 1. According to the degree of control by the control circuit signal, they can be divided into semi-controlled devices (such as thyristors), fully controlled devices (such as insulated gate bipolar transistors) and uncontrollable devices (such as power diodes); according to the nature of the signal added between the control terminal and the common terminal of the power semiconductor device by the drive circuit, they can be divided into voltage-driven devices (such as electrostatic induction thyristors) and current-driven devices (such as thyristors); according to the effective signal waveform added between the control terminal and the common terminal of the power semiconductor device by the drive circuit, they can be divided into pulse-triggered types (such as thyristors) and electronically controlled types (such as insulated gate bipolar transistors); according to the situation in which the two carriers of electrons and holes in the power semiconductor device participate in conduction, they can be divided into bipolar devices (such as power diodes), unipolar devices (such as Schottky barrier diodes) and composite devices (such as insulated gate bipolar transistors).

[0037] In this embodiment, the power semiconductor device 1 is an insulated gate bipolar transistor, that is, an IGBT (Insulated Gate Bipolar Transistor) as an example for explanation. The insulated gate bipolar transistor is a composite fully controlled voltage-driven power semiconductor device composed of a BJT (bipolar transistor) and a MOS (insulated gate field effect transistor). As a common electronic device, it has been widely used in various electronic devices, such as Figure 3 As shown, the equivalent circuit of the IGBT device can be regarded as the parallel connection of the IGBT chip 11 and the FWD chip 12, wherein the FWD (Freewheeling diode) is a freewheeling diode. The FWD is generally used in the circuit to protect the device from being broken down or burned out by the induced voltage. It is connected in parallel to the two ends of the device that generates the induced electromotive force and forms a loop with it, so that the high electromotive force generated by it is consumed in the loop in the form of freewheeling current, thereby protecting the devices in the circuit from being damaged.

[0038] It should be noted that, in the present embodiment, the power semiconductor device 1 is an insulated gate bipolar transistor (IGBT), which is only described as an example. The technical solution provided in the present embodiment can also be used to calculate the service life of other types of power semiconductor devices 1.

[0039] In this embodiment, the saturation voltage drop V CESAT It refers to the voltage drop between the collector and emitter of the IGBT chip 11 when it operates in the saturation region.

[0040] In the preferred technical solution of this embodiment, the life prompt unit 3 includes: a voltage drop comparison unit 4, the voltage drop comparison unit 4 is electrically connected to the saturation voltage drop detection unit 2, and the saturation voltage drop V detected by the saturation voltage drop detection unit 2 is CESAT With saturation voltage drop threshold V CESAT(TH) For comparison, the saturation voltage drop threshold V CESAT(TH) is the maximum saturation voltage drop of the power semiconductor device 1 , which can be obtained from the work manual of the power semiconductor device 1 and set in the voltage drop comparison unit 4 .

[0041] In the preferred technical solution of this embodiment, the life prompt unit 3 further includes: an alarm unit 5, which is connected to the output end of the voltage drop comparison unit 4 to CESAT >V CESAT(TH) When an alarm signal is sent, specifically, when V CESAT >V CESAT(TH)When the power semiconductor device 1 is operating in an overcurrent state and is likely to be damaged, a timely alarm can enable the user to discover and solve the problem in time to reduce the loss caused by sudden downtime of the equipment using the power semiconductor device 1 due to the failure of the power semiconductor device 1.

[0042] The above-mentioned implementation mode actually provides a solution for how to timely discover this problem when the life of the power semiconductor device 1 is about to end, and in order to be able to calculate the service life of the power semiconductor device 1 before the power semiconductor device 1 fails, so as to take countermeasures in advance, for example, during regular PM, the power semiconductor device 1 can be replaced in advance, so as to avoid sudden downtime of the equipment with the power semiconductor device 1.

[0043] In order to achieve this function, in the preferred technical solution of this embodiment, the life prompt unit 3 also includes: a storage unit 6, the storage unit 6 is electrically connected to the saturation voltage drop detection unit 2, and is used to store the saturation voltage drop V detected by the saturation voltage drop detection unit 2. CESAT In this embodiment, the storage unit 6 can store the saturation voltage drop V detected by the saturation voltage drop detection unit 2. CESAT The user can download the data regularly and analyze the service life of the power semiconductor device 1 according to the data. Specifically, the user can analyze the service life of the power semiconductor device 1 according to the saturation voltage drop V CESAT The historical data plots the saturation voltage drop V CESAT The corresponding growth curve with time changes (theoretically, as the power semiconductor device 1 works for a long time under the condition of cyclic load changes, the saturation voltage drop V CESAT will continue to increase), and the saturation voltage drop V CESAT The maximum value is related to the maximum saturation voltage drop V of the power semiconductor device 1 CESAT(TH) Compare and calculate the saturation voltage drop V accordingly CESAT Increase to the maximum saturation voltage drop V CESAT(TH) The time is the service life of the power semiconductor device 1. The user can judge whether the power semiconductor device 1 needs to be replaced according to the service life of the power semiconductor device 1. With this arrangement, the service life of the power semiconductor device 1 can be monitored. In particular, when there are multiple power semiconductor devices 1 in the device, the multiple power semiconductor devices 1 can be connected to the storage unit 6 at the same time to realize simultaneous monitoring of the multiple power semiconductor devices 1.

[0044] In the preferred technical solution of this embodiment, it also includes: a current detection circuit 7, the current detection circuit 7 is electrically connected to the saturation voltage drop detection unit 2 and the output end of the power semiconductor device 1 respectively, in response to the current detection circuit 7 detecting that the current at the output end of the power semiconductor device 1 reaches the threshold value, the saturation voltage drop detection unit 2 detects the current saturation voltage drop V of the power semiconductor device 1 CESAT .

[0045] In this technical solution, when the current at the output end of the power semiconductor device 1 reaches a certain threshold, it is determined that the device having the power semiconductor device 1 is in operation. Under this condition, the saturation voltage drop detection unit 2 is started to detect the current saturation voltage drop of the power semiconductor device 1, which can save energy and avoid detecting invalid data.

[0046] In the preferred technical solution of this embodiment, reference Figure 3 The saturation voltage drop detection unit 2 includes: a saturation voltage drop detection circuit 21, which is electrically connected to the power semiconductor device 1; a sampling circuit 22, which is electrically connected to the saturation voltage drop detection circuit 21 to detect the saturation voltage drop V CESAT shielding time setting circuit 23, and the sampling circuit 22 is electrically connected, so that the sampling circuit 22 starts sampling after a preset time T, to ensure that the sampling circuit 22 performs sampling when the power semiconductor device 1 operates in the saturation region.

[0047] Since in actual use, the power semiconductor device 1 does not enter the saturation region instantaneously, Figure 4 As shown, due to the early parasitic effects, V ge (the voltage drop between the gate and the emitter) is not a smooth curve. Therefore, if the voltage drop between the collector and the emitter of the IGBT chip 11 is measured before entering the saturation region, invalid data will be obtained. Therefore, it is necessary to set a shielding time setting circuit 23, which can make the power semiconductor device 1 work after the saturation region (V ge After stabilization), the sampling circuit 22 is used for sampling. By setting this, a more accurate saturation voltage drop V CESAT Check the value.

[0048] In addition, if Figure 5 As shown, the technical solution provided in this embodiment can also reduce the forward conduction voltage drop V of the FWD chip 12. F Similarly, the forward conduction of the FWD chip 12 is not instantaneous, so it is also necessary to set a shielding time setting circuit 23 so that after the forward conduction, it is sampled by the sampling circuit 22 to obtain its accurate forward conduction voltage drop V F ,in, Figure 5 V ak represents the voltage across the FWD chip 12, Ia represents the current flowing through the FWD chip 12. When the freewheeling is performed for a predetermined time, V F Sampling can obtain a more accurate forward conduction voltage drop V of the FWD chip 12. F .

[0049] Specifically, the mask time T set by the mask time setting circuit 23 is usually greater than 10 μs.

[0050] In the preferred technical solution of this embodiment, continue to refer to Figure 3 Specifically, the power semiconductor device 1 is an N-type IGBT, and the saturation voltage drop detection circuit 21 includes: a resistor R, a diode D and a Zener diode ZD connected in series between the collector and the emitter of the power semiconductor device 1, wherein one end of the resistor R is connected to the collector, and the other end is connected to the anode of the diode D, the cathode of the Zener diode ZD is connected to the cathode of the diode D, and the anode of the Zener diode ZD is connected to the emitter. Furthermore, the two input ends of the sampling circuit 22 are respectively connected to the anode of the diode D and the anode of the Zener diode ZD.

[0051] The saturation voltage drop V CESAT The detection method is described as follows. Initially, the IGBT chip 11 is in the off state. The voltage applied to both ends of the IGBT chip 11 forms a loop through the resistor R, the diode D and the Zener diode ZD. The current of the loop is limited by the resistor R. The sampling circuit 22 collects the voltage value across the Zener diode ZD at this time. When the power supply (not shown) applies a voltage of a predetermined amplitude and pulse width to the gate of the IGBT chip, when it enters a stable state, the voltage drop between the collector and the emitter of the IGBT chip becomes a saturation voltage drop V CESAT At this time, the IGBT chip and the load at the output end form a loop, and no current flows through the resistor R, the diode D and the Zener diode ZD. The voltage collected by the sampling circuit 22 is the saturation voltage drop V CESAT .

[0052] In a preferred technical solution of this embodiment, the sampling circuit 22 is an isolated analog-to-digital conversion circuit. In some alternative embodiments, the sampling circuit 22 may also be an oscilloscope or other device that can collect voltage information.

[0053] This embodiment also provides a method for detecting the service life of a power semiconductor module 100, which is used to detect the service life of the power semiconductor module 100. The service life detection method comprises the steps of: obtaining a saturation voltage drop V CESAT ; According to the saturation voltage drop V of the power semiconductor device 1 CESAT The service life of the power semiconductor device 1 is calculated.

[0054] It should be noted that, since the service life of the power semiconductor module 100 mainly depends on the service life of the power semiconductor device 1 , the detection of the service life of the power semiconductor device 1 can also be regarded as the detection of the service life of the power semiconductor module 100 .

[0055] This embodiment further provides an inverter device (not shown), comprising the power semiconductor module 100 described above.

[0056] So far, the technical solutions of the present invention have been described in conjunction with the accompanying drawings, but it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific technical solutions. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A power semiconductor module, characterized in that: include: Power semiconductor devices; A saturation voltage drop detection unit is electrically connected to the power semiconductor device to detect the saturation voltage drop V of the power semiconductor device. CESAT ; as well as The life prompt unit is connected to the saturation voltage drop detection unit and can detect the saturation voltage drop V according to the saturation voltage drop V CESAT issuing a prompt message, wherein the prompt message indicates the service life of the power semiconductor device; The life prompt unit also includes: A voltage drop comparison unit is electrically connected to the saturation voltage drop detection unit, and compares the saturation voltage drop V detected by the saturation voltage drop detection unit. CESAT With saturation voltage drop threshold V CESAT(TH) Make comparisons; A storage unit is electrically connected to the saturation voltage drop detection unit and is used to store the saturation voltage drop V detected by the saturation voltage drop detection unit. CESAT Historical data is available for users to download regularly to plot the saturation voltage drop V CESAT The growth curve varies with time and according to the saturation voltage drop V CESAT The historical data plots the saturation voltage drop V CESAT The growth curve of the change with time, and the saturation voltage drop V in the growth curve CESAT The maximum value and saturation voltage drop threshold V CESAT(TH) Compare and calculate the saturation voltage drop V accordingly CESAT Increase to the saturation voltage drop threshold V CESAT(TH) The time is used to improve the accuracy of estimating the service life of the power semiconductor device, and the time is the service life of the power semiconductor device.

2. The power semiconductor module according to claim 1, characterized in that The life prompt unit also includes: The alarm unit is connected to the output terminal of the voltage drop comparison unit to CESAT >V CESAT(TH) Send an alarm signal when 3. The power semiconductor module according to claim 1 or 2, characterized in that: Also includes: The current detection circuit is electrically connected to the saturation voltage drop detection unit and the output end of the power semiconductor device, respectively. In response to the current detection circuit detecting that the current at the output end of the power semiconductor device reaches a threshold value, the saturation voltage drop detection unit detects the current saturation voltage drop V of the power semiconductor device. CESAT .

4. The power semiconductor module according to claim 1 or 2, characterized in that: The saturation voltage drop detection unit comprises: A saturation voltage drop detection circuit, electrically connected to the power semiconductor device; A sampling circuit is electrically connected to the saturation voltage drop detection circuit to detect the saturation voltage drop V CESAT Take samples; The shielding time setting circuit is electrically connected to the sampling circuit so that the sampling circuit starts sampling after a preset time T, thereby ensuring that the power semiconductor device operates in a saturation region when the sampling circuit performs sampling.

5. The power semiconductor module according to claim 4, characterized in that The saturation voltage drop detection circuit comprises: A resistor R, a diode D and a zener diode ZD are connected in series between the collector and the emitter of the power semiconductor device, wherein one end of the resistor R is connected to the collector, and the other end is connected to the anode of the diode D, the cathode of the zener diode ZD is connected to the cathode of the diode D, and the anode of the zener diode ZD is connected to the emitter.

6. The power semiconductor module according to claim 5, characterized in that The two input terminals of the sampling circuit are connected to the anode of the diode D and the anode of the voltage stabilizing diode ZD respectively.

7. A method for detecting the service life of a power semiconductor module, used for detecting the service life of the power semiconductor module according to any one of claims 1 to 6, characterized in that: The life detection method comprises the steps of: Get the saturation voltage drop V of the power semiconductor device CESAT ; The saturation voltage drop V CESAT With saturation voltage drop threshold V CESAT(TH) Compare; and store the detected saturation voltage drop V CESAT Historical data to plot the saturation voltage drop V CESAT Growth curves over time; According to the saturation voltage drop V of the power semiconductor device CESAT Calculate the service life of power semiconductor devices; According to the saturation voltage drop V CESAT The historical data plots the saturation voltage drop V CESAT The growth curve of the change with time, and the saturation voltage drop V in the growth curve CESAT The maximum value and saturation voltage drop threshold V CESAT(TH) Compare and calculate the saturation voltage drop V accordingly CESAT Increase to the saturation voltage drop threshold V CESAT(TH) time.

8. An inverter device, characterized in that: Comprising a power semiconductor module as claimed in any one of claims 1 to 6.

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