A 3-level IGBT double-pulse test method

Abstract

The application discloses a kind of 3-level IGBT double-pulse test methods, specifically including the following operating steps: the tool needed for test is prepared, including host computer control software, hardware equipment, test board and capacitor bus, wherein test board includes test backplane and gate drive board;Fill in test parameters, control joint each measurement equipment communication and action;Hardware includes oscilloscope, signal generator, high-voltage DC power supply, low-voltage DC power supply, wherein oscilloscope is used to measure Vgs, Vds, Id, signal generator provides specific pulse width and phase double-pulse waveform, high-voltage DC power supply charges capacitor bus.The 3-level IGBT double-pulse test method of the application, gate output voltage control is simple and reliable, good stability, high precision, the control of gate signal can realize automatic switching, and manual switching compared with high reliability, convenient operation.

Description

Technical Field

[0001] This invention relates to the field of IGBT dual-pulse testing technology, and in particular to a dual-pulse testing method for 3-level IGBTs. Background Technology

[0002] The IGBT double-pulse test method is a supporting device for voltage detection of IGBT driver boards. A 3-level IGBT consists of four IGBT transistors. In the double-pulse test, the gate drive voltage must be output accurately and have a certain driving capability. It is mainly used to simplify the drive circuit, improve the drive accuracy, and control the signal type connected to the four IGBT driver boards by controlling the relay. With the continuous development of technology, people's requirements for the IGBT double-pulse test method are also getting higher and higher.

[0003] Existing IGBT double-pulse testing methods have certain drawbacks. First, they are relatively complex to use, lack stability, and have low accuracy, making them inconvenient for users. Second, they cannot automatically switch the gate signal effectively, making operation inconvenient and negatively impacting practical applications. Therefore, we propose a 3-level IGBT double-pulse testing method. Summary of the Invention

[0004] Technical problem solved: In view of the shortcomings of the prior art, the present invention provides a 3-level IGBT dual-pulse test method, which has simple and reliable gate output voltage control, good stability and high precision, and the gate signal control can realize automatic switching. Compared with manual switching, it has high reliability and convenient operation, and can effectively solve the problems in the background art.

[0005] Technical Solution: To achieve the above objectives, the technical solution adopted by this invention is: a 3-level IGBT dual-pulse testing method, specifically including the following operation steps:

[0006] S1: Test preparation: Prepare the tools needed for the test, including host computer control software, hardware equipment, test boards and capacitor busbars, among which the test boards include the test baseboard and the gate driver board.

[0007] S2: Host computer software: Fill in test parameters and control the communication and actions of various measuring devices;

[0008] S3: Hardware equipment: including oscilloscope, signal generator, high voltage DC power supply, and low voltage DC power supply. The oscilloscope is used to measure Vgs, Vds, and Id. The signal generator provides a dual-pulse waveform with a specific pulse width and phase. The high voltage DC power supply charges the capacitor busbars, and the low voltage DC power supply powers the test board.

[0009] S4: Test baseboard: The test baseboard is based on the STM32F103 series microcontroller as the main controller to complete the control connection between test boards;

[0010] S5: Gate Driver Board: The gate driver board uses an isolated power supply module in conjunction with a DC-DC power supply module to generate +21V and -18V DC voltages to provide support voltages for the linear regulator. The digital potentiometer of IIC communication can realize the programmable output of the linear regulator, thereby matching IGBT devices under test with different gate voltage requirements.

[0011] S6: Capacitor busbar: The high-voltage DC power supply charges the capacitor, which actually provides energy for the dual-pulse test.

[0012] As a preferred technical solution of this application, the test baseboard is divided into four driving circuits, which correspond one-to-one with the four IGBT devices inside the three-level module. The driving circuit adopts a pluggable method, which facilitates the replacement of the driving board.

[0013] As a preferred technical solution of this application, the test baseboard is programmed with a microcontroller, which can control the conduction or cutoff of the four devices inside the module in a targeted manner, and Vge, Vce, and Ie can be directly measured on the test baseboard.

[0014] As a preferred technical solution of this application, the test in steps S1-S6 includes a main control and communication circuit, a basic power supply circuit, a drive and signal detection circuit, a main circuit of the device under test, a gate drive voltage generation circuit, a gate drive voltage adjustment circuit, a gate drive voltage generation and pin lead-out circuit, and a gate drive signal output circuit.

[0015] As a preferred technical solution of this application, in step S5, the power supply of the IGBT driver chip is divided into positive voltage and negative voltage. The positive and negative voltages are output through an LDO chip. The output feedback pin of the LDO chip is connected to a digital potentiometer. By adjusting the resistance of the digital potentiometer, the output voltage of the LDO is automatically changed, thereby providing different IGBT drive voltages.

[0016] As a preferred technical solution of this application, a signal relay is set in step S5. The signal relay is a single-pole double-throw relay to select different signals. The input signals of the gate driver board are divided into three types: double pulse signal, high level and low level.

[0017] As a preferred technical solution of this application, the switching of two signal relays is used to allocate the corresponding signal to the signal input port. When the signal needs to be low level, relay 1 is selected to be disconnected and relay 2 is disconnected.

[0018] As a preferred technical solution of this application, when a high level signal is required, relay 1 is activated and relay 2 is activated.

[0019] As a preferred technical solution of this application, when the signal requires a double pulse, relay 1 is activated and relay 2 is deactivated.

[0020] Beneficial Effects: Compared with existing technologies, this invention provides a 3-level IGBT double-pulse testing method with the following beneficial effects: This 3-level IGBT double-pulse testing method features simple and reliable gate output voltage control, good stability, and high precision. It enables automatic switching of the gate signal control, offering higher reliability and easier operation compared to manual switching. The IGBT driver chip is powered by both positive and negative voltages, output through an LDO chip. The LDO chip's output feedback pin is not connected to a fixed resistor value but to a digital potentiometer. Adjusting the digital potentiometer automatically changes the LDO's output voltage, thus providing different IGBT drive voltages. This method is simple, efficient, stable, and reliable. Single-pole double-throw relays are used for selecting different signals. The gate driver board receives three types of input signals: double-pulse signal, high level, and low level. This method uses the switching of two signal relays to allocate the corresponding signals to the signal input ports. When a low level signal is required, relay 1 is disconnected, and relay 2 is disconnected. When a high level signal is required, relay 1 is energized, and relay 2 is energized. When a double pulse is required for the signal, relay 1 is activated and relay 2 is deactivated. The entire IGBT double pulse test method has a simple structure, is easy to operate, and performs better than the traditional method. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the main control and communication circuit in a 3-level IGBT dual-pulse testing method of the present invention.

[0022] Figure 2 This is a schematic diagram of the basic power supply circuit in a 3-level IGBT dual-pulse testing method of the present invention.

[0023] Figure 3 This is a schematic diagram of the driving and signal detection circuit in a 3-level IGBT dual-pulse testing method of the present invention.

[0024] Figure 4 This is a schematic diagram of the main circuit of the device under test in a 3-level IGBT double-pulse test method of the present invention.

[0025] Figure 5 This is a schematic diagram of the gate drive voltage generation circuit in a 3-level IGBT dual-pulse testing method of the present invention.

[0026] Figure 6 This is a schematic diagram of the gate drive voltage adjustment circuit in a 3-level IGBT dual-pulse testing method of the present invention.

[0027] Figure 7 This is a schematic diagram of the gate drive voltage generation and pin lead-out circuit in a 3-level IGBT double-pulse test method of the present invention.

[0028] Figure 8 This is a schematic diagram of the gate drive signal output circuit in a 3-level IGBT double-pulse test method of the present invention.

[0029] Figure 9 This is a schematic diagram of the driving circuit in a 3-level IGBT double-pulse testing method of the present invention.

[0030] Figure 10 This is a schematic diagram of the relay circuit in a 3-level IGBT double-pulse testing method of the present invention. Detailed Implementation

[0031] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0032] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0034] like Figure 1-10 As shown, a dual-pulse test method for a 3-level IGBT specifically includes the following steps:

[0035] S1: Test preparation: Prepare the tools needed for the test, including host computer control software, hardware equipment, test boards and capacitor busbars, among which the test boards include the test baseboard and the gate driver board.

[0036] S2: Host computer software: Fill in test parameters and control the communication and actions of various measuring devices;

[0037] S3: Hardware equipment: including oscilloscope, signal generator, high voltage DC power supply, and low voltage DC power supply. The oscilloscope is used to measure Vgs, Vds, and Id. The signal generator provides a dual-pulse waveform with a specific pulse width and phase. The high voltage DC power supply charges the capacitor busbars, and the low voltage DC power supply powers the test board.

[0038] S4: Test baseboard: The test baseboard is based on the STM32F103 series microcontroller as the main controller to complete the control connection between test boards;

[0039] S5: Gate Driver Board: The gate driver board uses an isolated power supply module in conjunction with a DC-DC power supply module to generate +21V and -18V DC voltages to provide support voltages for the linear regulator. The digital potentiometer of IIC communication can realize the programmable output of the linear regulator, thereby matching IGBT devices under test with different gate voltage requirements.

[0040] S6: Capacitor busbar: The high-voltage DC power supply charges the capacitor, which actually provides energy for the dual-pulse test.

[0041] The gate output voltage control is simple, reliable, stable, and highly accurate. The gate signal control can achieve automatic switching, which is more reliable and easier to operate than manual switching.

[0042] The test baseboard has four drive circuits, each corresponding to one of the four IGBT devices inside the three-level module. The drive circuits are pluggable, making it easy to replace the drive board.

[0043] The test baseboard is programmed with a microcontroller, which can control the conduction or cutoff of four devices inside the module in a targeted manner, and Vge, Vce, and Ie can be directly measured on the test baseboard.

[0044] The tests in steps S1-S6 include the main control and communication circuit, the basic power supply circuit, the drive and signal detection circuit, the main circuit of the device under test, the gate drive voltage generation circuit, the gate drive voltage adjustment circuit, the gate drive voltage generation and pin lead-out circuit, and the gate drive signal output circuit.

[0045] In step S5, the power supply to the IGBT driver chip is divided into positive voltage and negative voltage. The positive and negative voltages are output through an LDO chip. The output feedback pin of the LDO chip is connected to a digital potentiometer. By adjusting the resistance of the digital potentiometer, the output voltage of the LDO is automatically changed, thereby providing different IGBT drive voltages.

[0046] In step S5, signal relays are set up. These are single-pole double-throw relays, used to select different signals. The input signals to the gate driver board are divided into three types: double-pulse signal, high level, and low level. The switching of the two signal relays distributes the corresponding signals to the signal input ports. When a low level signal is required, relay 1 is disconnected and relay 2 is disconnected; when a high level signal is required, relay 1 is energized and relay 2 is energized; when a double-pulse signal is required, relay 1 is energized and relay 2 is disconnected.

[0047] A test device for a 3-level IGBT dual-pulse test method consists of four parts:

[0048] 1. Host computer control software

[0049] 2. Hardware equipment

[0050] 3. Test board

[0051] 4. Capacitor busbar

[0052] The measurement board consists of two parts:

[0053] 1. Test base plate;

[0054] 2. Gate driver board;

[0055] Circuit principle:

[0056] Host computer software:

[0057] Fill in the relevant test parameters and control the communication and actions of the various measuring devices.

[0058] Hardware equipment:

[0059] The system consists of an oscilloscope, a signal generator, a high-voltage DC power supply, and a low-voltage DC power supply. The oscilloscope measures Vgs, Vds, and Id; the signal generator provides a dual-pulse waveform with specific pulse width and phase; the high-voltage DC power supply charges the capacitor busbars; and the low-voltage DC power supply powers the test board.

[0060] Test base plate:

[0061] The test baseboard uses an STM32F103 series microcontroller as the main controller to complete the control connection between test boards. The baseboard has four drive circuits, each corresponding to one of the four IGBT devices inside the three-level module. The drive circuits are pluggable for easy replacement of the drive boards.

[0062] By using microcontroller programming, the conduction or shutdown of the four devices inside the module can be controlled in a targeted manner.

[0063] Vge, Vce, and Ie can be directly measured on the base plate;

[0064] Gate driver board:

[0065] The gate driver board utilizes an isolated power supply module in conjunction with a DC-DC power supply module to generate +21V and -18V DC voltages to provide support voltages for the linear regulator. The digital potentiometer for IIC communication enables programmable outputs from the linear regulator, thus matching IGBT devices under test with different gate voltage requirements.

[0066] Capacitor busbar:

[0067] The high-voltage DC power supply charges the capacitor, which in turn provides energy for the dual-pulse test.

[0068] Working Principle: The IGBT driver chip is powered by both positive and negative voltages, which are output through an LDO chip. The LDO chip's output feedback pin is not connected to a fixed resistor value, but rather to a digital potentiometer. Adjusting the potentiometer automatically changes the LDO's output voltage, thus providing different IGBT drive voltages. This method is simple, efficient, stable, and reliable. Single-pole double-throw (SPDT) relays are used for selecting different signals. The gate driver board receives three types of input signals: double-pulse signal, high level, and low level. This method uses the switching of two signal relays to distribute the corresponding signals to the signal input ports. When a low level is required, relay 1 is off and relay 2 is off. When a high level is required, relay 1 is on and relay 2 is on. When a double-pulse signal is required, relay 1 is on and relay 2 is off.

[0069] It should be noted that, in this document, relational terms such as first and second (number one, number two), etc., are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0070] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A method for testing 3-level IGBTs using a dual-pulse method, characterized in that: Specifically, the following steps are included: S1: Test preparation: Prepare the tools needed for the test, including host computer control software, hardware equipment, test boards and capacitor busbars, among which the test boards include the test baseboard and the gate driver board. S2: Host computer software: Fill in test parameters and control the communication and actions of various measuring devices; S3: Hardware equipment: including oscilloscope, signal generator, high voltage DC power supply, and low voltage DC power supply. The oscilloscope is used to measure Vgs, Vds, and Id. The signal generator provides a dual-pulse waveform with a specific pulse width and phase. The high voltage DC power supply charges the capacitor busbars, and the low voltage DC power supply powers the test board. S4: Test baseboard: The test baseboard is based on the STM32F103 series microcontroller as the main controller to complete the control connection between test boards; S5: Gate Driver Board: The gate driver board uses an isolated power supply module in conjunction with a DC-DC power supply module to generate +21V and -18V DC voltages to provide support voltages for the linear regulator. The digital potentiometer of IIC communication can realize the programmable output of the linear regulator, thereby matching IGBT devices under test with different gate voltage requirements. S6: Capacitor busbar: The high-voltage DC power supply charges the capacitor, which actually provides energy for the dual-pulse test.

2. The method for testing a 3-level IGBT with a dual-pulse according to claim 1, characterized in that: The test baseboard has four drive circuits, each corresponding to one of the four IGBT devices inside the three-level module. The drive circuits are pluggable, making it easy to replace the drive board.

3. The method for testing a 3-level IGBT with a dual-pulse according to claim 1, characterized in that: The test baseboard is programmed with a microcontroller, which can control the conduction or cutoff of the four devices inside the module in a targeted manner, and Vge, Vce, and Ie can be directly measured on the test baseboard.

4. The method for testing a 3-level IGBT with a dual-pulse according to claim 1, characterized in that: The tests in steps S1-S6 include the main control and communication circuit, the basic power supply circuit, the drive and signal detection circuit, the main circuit of the device under test, the gate drive voltage generation circuit, the gate drive voltage adjustment circuit, the gate drive voltage generation and pin lead-out circuit, and the gate drive signal output circuit.

5. The method for testing a 3-level IGBT with a dual-pulse according to claim 1, characterized in that: In step S5, the power supply to the IGBT driver chip is divided into positive voltage and negative voltage. The positive and negative voltages are output through an LDO chip. The output feedback pin of the LDO chip is connected to a digital potentiometer. By adjusting the resistance of the digital potentiometer, the output voltage of the LDO is automatically changed, thereby providing different IGBT drive voltages.

6. The method for testing a 3-level IGBT dual-pulse according to claim 1, characterized in that: In step S5, a signal relay is set. The signal relay is a single-pole double-throw relay to select different signals. The input signals of the gate driver board are divided into three types: double pulse signal, high level and low level.

7. The method for testing a 3-level IGBT dual-pulse according to claim 6, characterized in that: Two signal relays are used to switch and distribute the corresponding signal to the signal input port. When a low level signal is required, relay 1 is turned off and relay 2 is turned off.

8. The method for testing a 3-level IGBT dual-pulse according to claim 7, characterized in that: When a high level signal is required, relay 1 is activated and relay 2 is activated.

9. The method for testing a 3-level IGBT dual-pulse according to claim 7, characterized in that: When a double pulse is required for the signal, relay 1 is activated and relay 2 is deactivated.

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