A method suitable for IGBT 14000A large current double pulse and short circuit driving and protection

Abstract

The application discloses a kind of suitable for IGBT14000A large current double pulse and short circuit driving and protection method, based on the hardware system of main circuit module, control module, driving module and protection module composition, realize circuit driving and protection integration application, specific method includes the following steps: system self-checking: control module starts self-checking function, detects power voltage, driving circuit output impedance, protection circuit response state and other key parameters, after self-checking passes, it can start test.The application discloses a kind of suitable for IGBT14000A large current double pulse and short circuit driving and protection method, by the design of driving and protection integration driving circuit board, realize not less than 50A driving current, give consideration to excellent interference filtering algorithm, complete double pulse test on pipe all functions, simultaneously have program controllable test starting longest delay timeout self-cutting and pre-test function, guarantee the reliability of test system and the test safety of IGBT device.

Description

Technical Field

[0001] This invention relates to the field of IGBT testing technology, and in particular to a method for driving and protecting IGBT 14000A with high current dual pulse and short circuit. Background Technology

[0002] The IGBT14000A high-current dual-pulse and short-circuit drive and protection method is a dynamic performance test and short-circuit reliability assessment method applicable to various high-power IGBT devices under extreme operating conditions. Insulated gate bipolar transistors (IGBTs), as core power devices in the field of power electronics, are widely used in high-power scenarios such as new energy vehicles, rail transit, and energy storage systems. Dual-pulse testing is a key means of evaluating their dynamic performance, and the test current level needs to match the actual application conditions. With the continuous development of technology, people's requirements for the IGBT14000A high-current dual-pulse and short-circuit drive and protection method are also getting higher and higher.

[0003] The existing IGBT 14000A high-current dual-pulse and short-circuit drive and protection methods have certain drawbacks in use. The output current of the drive circuit is limited, which makes it difficult to meet the fast turn-on requirements of 14000A high-current IGBTs, and easily causes turn-on delay and increased conduction loss.

[0004] The protection mechanism is simple, mostly only having basic overcurrent protection, without DESAT oversaturation deprotection function, and cannot quickly cut off the drive signal under oversaturation conditions, which can easily lead to permanent damage to the device;

[0005] The port overvoltage protection capability is weak, and the voltage spikes generated by the parasitic inductance of the line can easily break down the drive port, affecting the system stability and test safety;

[0006] The low functional integration and the need for multiple independent devices to complete the dual-pulse test and short-circuit test make the operation complex and costly. To address this, we propose a high-current dual-pulse and short-circuit drive and protection method suitable for IGBT14000A. Summary of the Invention

[0007] Technical problem solved: To address the shortcomings of existing technologies, this invention provides a high-current dual-pulse and short-circuit driving and protection method suitable for IGBT 14000A. Through an integrated driving circuit board design for driving and protection, it achieves a driving current of no less than 50A, incorporates an excellent interference filtering algorithm, completes all functions of dual-pulse test on-device operation, and also features programmable controllable self-cutoff after the longest delay timeout after test start and pre-test self-check functions, ensuring the reliability of the test system and the test safety of IGBT devices, effectively solving the problems in the background technology.

[0008] Technical Solution: To achieve the above objectives, the technical solution adopted by this invention is as follows: a method for high-current dual-pulse and short-circuit driving and protection of IGBT14000A, based on a hardware system composed of a main circuit module, a control module, a drive module, and a protection module, realizing integrated circuit driving and protection applications. The specific method includes the following steps:

[0009] S1: System self-test: The control module starts the self-test function to detect key parameters such as power supply voltage, drive circuit output impedance, and protection circuit response status. The test can only be started after the self-test is passed.

[0010] S2: Parameter settings: Test parameters such as test mode, pulse width, number of tests, and delay time can be set through the human-machine interface;

[0011] S3: Test execution: The control module generates a dual-pulse control signal, which is processed by the interference filtering algorithm and then output to the drive module to control the IGBT to turn on and off. The main circuit module provides a 14000A test current or short-circuit condition according to the test mode.

[0012] S4: Real-time monitoring: The drive module monitors the IGBT collector-emitter voltage and drive circuit board port voltage in real time, and the control module monitors the test duration in real time.

[0013] S5: Fault Handling: If any of the following occurs: IGBT oversaturation, port overvoltage, test timeout, or self-test fault, the protection module will be triggered immediately, the audible and visual alarm will be activated, and the main circuit power will be cut off.

[0014] S6: Results Recording: After the test is completed, the system automatically records the test data and waveforms and generates a test report;

[0015] The drive module is based on the UCC21750 chip and designed as a drive circuit board to achieve a drive current output of no less than 50A. It also integrates MOS drive tube expansion, DESAT oversaturation deactivation, and port overvoltage protection units.

[0016] As a preferred technical solution of this application, the MOS driving transistor expansion unit of the driving module is to connect at least 4 IRF540N type MOS driving transistors in parallel at the output terminal of the UCC21750 chip. The gate of the MOS transistor is connected to the output terminal of the chip through a 10Ω current limiting resistor. The source is grounded and the drain is connected to the gate of the IGBT to form a current superposition loop. The measured driving current can reach 55A.

[0017] As a preferred technical solution of this application, the DESAT oversaturation protection unit of the drive module consists of a 10kΩ and a 1kΩ voltage divider resistor and a 1nF filter capacitor. The voltage divider resistor is connected in series between the IGBT collector and ground. The intermediate node is connected to the DESAT pin of the UCC21750 chip through a 1kΩ current-limiting resistor. The filter capacitor is connected in parallel across the 1kΩ voltage divider resistor. When the IGBT is oversaturated and the collector-emitter voltage rises to above 10V, the chip immediately shuts off the drive output, and the protection response time is less than 10μs.

[0018] As a preferred technical solution of this application, the port overvoltage protection unit of the drive module is a high-power TVS diode of type SMBJ18CA connected in parallel at the 15V power supply port of the drive circuit board. The TVS diode has a breakdown voltage of 18V, a peak pulse power of 600W, and a response time of less than 1ns, which can limit the port overvoltage spike to within 18V.

[0019] As a preferred technical solution of this application, the main circuit module includes a 0-1000V adjustable DC power supply, a 1000μF / 1200V energy storage capacitor bank, a high-frequency pulse transformer with a turns ratio of 1:1, a 50μH load inductor, and a thyristor short-circuit test branch. The switching between dual-pulse test and short-circuit test modes is realized by switching the switch. The energy storage capacitor bank discharges through the load inductor to generate a stable 14000A test current.

[0020] As a preferred technical solution of this application, the control module adopts a Xilinx Kintex-7 series FPGA chip, integrates a Kalman filter interference filtering algorithm, and is equipped with an RC filter circuit and a Schmitt trigger to filter and shape the control signal; it has a built-in programmable delay timeout self-cut-off module, the maximum delay can be set to 10s, and the drive signal is automatically cut off after the timeout.

[0021] As a preferred technical solution of this application, the dual-pulse control signal generated by the control module has a frequency of 10kHz, an adjustable pulse width, and fully meets all the timing function requirements of the IGBT dual-pulse test upper tube.

[0022] As a preferred technical solution of this application, the protection module includes an audible and visual alarm unit and an emergency stop relay, which are linked with the DESAT oversaturation deprotection unit and port overvoltage protection unit of the drive module and the self-test module and timeout self-cut-off module of the control module to realize system-level fault alarm and emergency stop, forming a multi-level fault protection system.

[0023] Beneficial effects: Compared with the prior art, the present invention provides a method for driving and protecting IGBT14000A with high current dual pulse and short circuit, which has the following beneficial effects: This method for driving and protecting IGBT14000A with high current dual pulse and short circuit, through the integrated drive circuit board design of drive and protection, achieves a drive current of not less than 50A, takes into account the excellent interference filtering algorithm, completes all functions of dual pulse test on the tube, and has the functions of self-cutting after the longest delay after program-controllable test start and self-test before test, so as to ensure the reliability of the test system and the test safety of IGBT devices;

[0024] Drive current extension technology: By connecting multiple MOS drive transistors in parallel at the output of the UCC21750 chip, the drive current is increased to more than 50A to meet the drive requirements of 14000A high-current IGBT modules.

[0025] DESAT oversaturation protection technology: Utilizing the built-in DESAT detection function of the UCC21750 chip, in conjunction with external voltage divider resistors and filter capacitors, it realizes real-time monitoring and rapid de-saturation protection of IGBTs.

[0026] Port overvoltage protection technology: High-power TVS diodes are configured at each port of the driver circuit board to achieve nanosecond-level overvoltage protection response, protecting the driver chip and related circuits;

[0027] Functional integration technology: Integrates dual-pulse testing and short-circuit testing functions into one system, completing two different types of tests through the same system;

[0028] Strong driving capability: With the UCC21750 chip and multi-channel MOS driver tube expansion design, the driving current can reach more than 50A, which can meet the driving requirements of 14000A high current IGBT and short circuit test, and solve the problem of insufficient current in traditional driving circuits.

[0029] Comprehensive protection mechanisms: It integrates multiple protection functions such as DESAT oversaturation protection, port overvoltage protection, and delay timeout protection to ensure the safety and reliability of the testing process;

[0030] Comprehensive protection mechanisms: It integrates multiple protection functions such as DESAT oversaturation protection, port overvoltage protection, and delay timeout protection to ensure the safety and reliability of the testing process;

[0031] High functional integration: It realizes the integration of driving and protection, integrates interference filtering algorithm, full function of upper tube test, delay overtime self-cut-off and self-test function. Compared with the existing system, it has more comprehensive functions, significantly improves test safety and reliability, and can complete dual-pulse dynamic test and short circuit test at the same time.

[0032] High compatibility: The driver circuit board design based on the UCC21750 chip has good compatibility and can be adapted to different models of 14000A IGBT devices, reducing the adaptation cost of the test system. The entire IGBT 14000A high current dual pulse and short circuit drive and protection method has a simple structure, is easy to operate, and has better performance than traditional methods. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the overall structure of a high-current dual-pulse and short-circuit driving and protection method for IGBT14000A according to the present invention.

[0034] Figure 2 This is a schematic diagram of the UCC21750 driver circuit board used in the driving module of the IGBT14000A high-current dual-pulse and short-circuit driving and protection method of the present invention.

[0035] Figure 3 This is a circuit diagram of the DESAT oversaturation deactivation unit in a high-current dual-pulse and short-circuit drive and protection method for IGBT14000A.

[0036] Figure 4 This is a circuit diagram of a port overvoltage protection unit in a high-current dual-pulse and short-circuit drive and protection method for IGBT14000A according to the present invention. Detailed Implementation

[0037] 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.

[0038] 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.

[0039] 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.

[0040] like Figure 1-4 As shown, a high-current dual-pulse and short-circuit driving and protection method suitable for IGBT14000A is proposed. Based on a hardware system consisting of a main circuit module, a control module, a drive module, and a protection module, it realizes integrated circuit driving and protection applications. The specific method includes the following steps:

[0041] S1: System self-test: The control module starts the self-test function to detect key parameters such as power supply voltage, drive circuit output impedance, and protection circuit response status. The test can only be started after the self-test is passed.

[0042] S2: Parameter settings: Test parameters such as test mode, pulse width, number of tests, and delay time can be set through the human-machine interface;

[0043] S3: Test execution: The control module generates a dual-pulse control signal, which is processed by the interference filtering algorithm and then output to the drive module to control the IGBT to turn on and off. The main circuit module provides a 14000A test current or short-circuit condition according to the test mode.

[0044] S4: Real-time monitoring: The drive module monitors the IGBT collector-emitter voltage and drive circuit board port voltage in real time, and the control module monitors the test duration in real time.

[0045] S5: Fault Handling: If any of the following occurs: IGBT oversaturation, port overvoltage, test timeout, or self-test fault, the protection module will be triggered immediately, the audible and visual alarm will be activated, and the main circuit power will be cut off.

[0046] S6: Results Recording: After the test is completed, the system automatically records the test data and waveforms and generates a test report;

[0047] The driver module is designed based on the UCC21750 chip to achieve a drive current output of no less than 50A, and integrates MOS driver tube expansion, DESAT oversaturation deactivation, and port overvoltage protection units.

[0048] The MOS driver expansion unit of the driver module consists of at least four IRF540N type MOS driver transistors connected in parallel at the output of the UCC21750 chip. The gate of the MOS transistor is connected to the output of the chip through a 10Ω current-limiting resistor. The source is grounded and the drain is connected to the gate of the IGBT to form a current superposition loop. The measured drive current can reach 55A.

[0049] The DESAT oversaturation protection unit of the drive module consists of a 10kΩ and a 1kΩ voltage divider resistor and a 1nF filter capacitor. The voltage divider resistor is connected in series between the IGBT collector and ground. The intermediate node is connected to the DESAT pin of the UCC21750 chip through a 1kΩ current-limiting resistor. The filter capacitor is connected in parallel across the 1kΩ voltage divider resistor. When the IGBT is oversaturated and the collector-emitter voltage rises above 10V, the chip immediately shuts off the drive output, and the protection response time is less than 10μs.

[0050] The port overvoltage protection unit of the drive module is a high-power TVS diode SMBJ18CA connected in parallel at the 15V power port of the drive circuit board. This TVS diode has a breakdown voltage of 18V, a peak pulse power of 600W, and a response time of less than 1ns, which can limit the port overvoltage spike to within 18V.

[0051] The main circuit module includes a 0-1000V adjustable DC power supply, a 1000μF / 1200V energy storage capacitor bank, a 1:1 high-frequency pulse transformer, a 50μH load inductor, and a thyristor short-circuit test branch. The dual-pulse test and short-circuit test modes are switched by a switching switch. The energy storage capacitor bank discharges through the load inductor to generate a stable 14000A test current.

[0052] The control module uses a Xilinx Kintex-7 series FPGA chip, which integrates a Kalman filter interference removal algorithm and is equipped with an RC filter circuit and a Schmitt trigger to filter and shape the control signal. It has a built-in programmable delay timeout self-cut-off module with a maximum delay of 10s, which automatically cuts off the drive signal after the timeout.

[0053] The control module generates a dual-pulse control signal with a frequency of 10kHz and an adjustable pulse width. This control signal fully meets all the timing function requirements of the IGBT dual-pulse test tube.

[0054] The protection module includes an audible and visual alarm unit and an emergency stop relay, which work in conjunction with the DESAT oversaturation deprotection unit and port overvoltage protection unit of the drive module, as well as the self-test module and timeout self-cut-off module of the control module to achieve system-level fault alarm and emergency stop, forming a multi-level fault protection system.

[0055] Hardware protection content

[0056] 1. Driver circuit board structure: The overall layout and circuit connection relationship of the driver circuit board based on the UCC21750 chip.

[0057] 2. MOS driver expansion circuit: including the number and model selection of MOS transistors, connection method, and design of related resistor parameters.

[0058] 3. DESAT protection circuit: including the selection of voltage divider resistor values, filter capacitor capacitance, and connection method with the UCC21750 chip.

[0059] 4. Port overvoltage protection circuit: including the selection of TVS diode model, connection position and overall design of protection circuit.

[0060] 5. Main circuit topology: including the connection relationship and parameter configuration of DC power supply, energy storage capacitor bank, pulse transformer, load inductor and short-circuit test branch.

[0061] Software protection content

[0062] 1. Control program algorithms: Dual pulse signal generation algorithm, interference filtering algorithm, delay control algorithm, etc. implemented in the embedded system.

[0063] 2. Fault Detection and Handling Program: The program logic for system fault detection, fault diagnosis, and fault handling.

[0064] 3. Human-computer interaction program: A program that enables functions such as setting test parameters, monitoring the test process, and displaying test results.

[0065] System integration protection content

[0066] 1. System overall architecture: the connection relationship and signal flow between the main circuit module, control module, drive module and protection module.

[0067] 2. Test mode switching mechanism: Control logic for switching between dual-pulse test mode and short-circuit test mode.

[0068] 3. Protection linkage mechanism: The coordination mechanism between various protection units ensures that protection actions can be executed quickly and accurately in the event of a fault.

[0069] like Figure 1As shown in this embodiment, the application and method for high-current dual-pulse and short-circuit testing of IGBT14000A based on the UCC21750 driver circuit includes a main circuit module, a control module, a driver module, and a protection module. The main circuit module consists of a DC power supply (output voltage 0-1000V), a 1000μF / 1200V energy storage capacitor bank, a high-frequency pulse transformer (turns ratio 1:1), a 50μH load inductor, and a thyristor short-circuit branch, and can switch between dual-pulse and short-circuit test modes. The control module uses a Xilinx Kintex-7 series FPGA chip with a built-in Kalman filter interference removal algorithm to generate a 10kHz frequency, adjustable pulse width dual-pulse control signal (supporting upper-side test timing). The delay timeout self-cutoff is set to 5s. The self-test module uses an ADC to collect key voltage and current signals to determine the component status. The driver module is a driver circuit board based on the UCC21750 chip. The protection module includes an audible and visual alarm unit and an emergency stop relay.

[0070] like Figure 2As shown, this circuit is a modular power control and drive system, mainly composed of a power input module, a core control module, and a power output module. The power input module is located in the upper left of the circuit, connected to an external power source via a connector, and provides a stable DC input after capacitor filtering. The core control module contains multiple integrated circuits: the UCC21750 driver circuit board of the drive module includes the UCC21750 IGBT driver chip (code U2), the WRE1215S-3W2 IGBT driver chips (codes U1 and U10), a MOS driver transistor expansion unit (MOS transistors Q1-Q4, resistors Ron1-10), a DESAT oversaturation de-protection chip input unit, a port overvoltage protection unit, and an interference filtering auxiliary circuit. U1, U2, and U10 are used, with U2 acting as the main controller, responsible for receiving external control signals and generating corresponding drive commands; U1 and U10 act as auxiliary control power modules, respectively implementing signal conditioning and protection functions. The power output module is located in the middle of the circuit, composed of multiple power transistors and a drive circuit, converting the control signals into power output capable of driving external loads. The VDD pin of the UCC21750 chip U1 is connected to a 15V power supply, the GND pin is grounded, and the IN+ and IN- pins are connected to the filtered dual-pulse control signal for controlling the IGBT output. The gates of MOSFETs Q1-Q4 are connected to the HO and LO outputs of the UCC21750 chip U1 respectively through resistors R1-R4. The sources are grounded, and the drains are connected to the IGBT gate, achieving superposition of drive currents. The measured drive current reaches 55A. The UCC21750 chip uses a three-phase bridge circuit composed of multiple power transistors Q1-Q4. Each bridge arm contains two power devices, an upper transistor and a lower transistor, which can provide bidirectional current drive. The circuit has a complete protection mechanism, including overcurrent protection resistors, overvoltage protection diodes, and fault detection circuits, to ensure safe operation of the system under abnormal conditions. This circuit is suitable for applications requiring precise control and high reliability, such as industrial automation equipment and robot control systems.

[0071] like Figure 3As shown, this circuit is a high-performance, high-power DESAT oversaturation de-protection acquisition unit driver circuit, specifically designed to drive industrial-grade power modules. The right side of the circuit is the high-voltage input section, capable of handling DC 1000V, including EMI filtering and absorption circuitry and drive overvoltage protection components. The DESAT oversaturation de-protection acquisition unit consists of resistor R35 (100Ω), Schottky diodes D10, D11, D4, D5, D7, D8, and fast transient diode D6. The DESAT_IN signal is connected to the pin of the UCC21750 chip U1. The central part consists of the core drive section protection module Q9 (FZ3600R17KE4). When the IGBT (FZ3600R17KE4) is operating normally, its collector-emitter voltage Vce is approximately 2V, and the DESAT pin voltage is approximately 0.2V. When the IGBT is oversaturated, Vce rises above 10V, and the DESAT pin voltage exceeds 1V. The UCC21750 chip U1 immediately shuts off the HO and LO outputs and outputs a fault signal to the protection module, triggering an audible and visual alarm. D6 is a fast transient diode used for surge protection, and resistors C9, C10, C11, C12, R37, and R38 are used for filtering and absorbing high-voltage spikes.

[0072] like Figure 4 As shown, this circuit is a high-speed differential signal processing circuit designed for processing high-frequency differential signals. The core of the circuit is the differential routing design (marked in red). Precision current sensing resistors R16, R17, R21, R22, R23, R25, and R27-R34 are also included to monitor the current in each phase in real time, achieving overcurrent protection and current closed-loop control. This routing method effectively suppresses common-mode noise and improves the anti-interference capability of signal transmission. The circuit includes two precision capacitors, C36 (100pF / 50V) and C35 (10pF / 50V), used for high-frequency noise filtering and signal coupling, respectively. Resistors R68 and R69 are used for impedance matching to ensure signal integrity on the transmission line and reduce reflections. The blue diode TVS1 provides signal limiting protection to prevent overvoltage damage to subsequent circuits. The entire circuit layout is compact, with particular attention paid to signal line routing and impedance control, reflecting the professional requirements of high-speed circuit design. This circuit is suitable for applications requiring high-speed digital signal transmission, such as data acquisition systems, and can ensure reliable signal transmission in complex electromagnetic environments.

[0073] The testing process in this embodiment is as follows: Before testing, the control module starts its self-test function to detect the power supply voltage, drive circuit output impedance, and protection circuit response status. The test can only start after the self-test is passed. The control module FPGA generates a dual-pulse control signal, which is processed by the interference filtering algorithm and output to the UCC21750 drive circuit board of the drive module to control the IGBT turn on and off. The main circuit module can select dual-pulse test (energy storage capacitor bank discharges to generate a 14000A large current through the load inductor) or short-circuit test (triggers the thyristor short-circuit branch to realize the IGBT short-circuit condition). During the test, the DESAT oversaturation de-protection unit monitors the IGBTTVce voltage in real time, the port overvoltage protection unit monitors the power port voltage, and the control module monitors the test duration in real time. If the delay exceeds 5 seconds, the drive signal is automatically cut off. When oversaturation, overvoltage, timeout, or self-test fault occurs, the drive module or control module outputs a fault signal to the protection module. The protection module immediately starts an audible and visual alarm and triggers the emergency stop relay to cut off the main circuit power supply to achieve fault protection.

[0074] Example 1: System Overall Architecture

[0075] like Figure 1 As shown, the IGBT14000A high-current dual-pulse and short-circuit test system based on the UCC21750 driver chip provided in this embodiment includes a main circuit module, a control module, a drive module, and a protection module.

[0076] Main circuit module: It consists of a DC power supply (output voltage adjustable from 0-1000V), a 1000μF / 1200V energy storage capacitor bank, a high-frequency pulse transformer (turn ratio 1:1), a 50μH load inductor and a thyristor short-circuit branch. The dual-pulse test and short-circuit test modes can be switched by a switching switch.

[0077] Control module: It adopts Xilinx Kintex-7 series FPGA chip, with built-in Kalman filter interference filtering algorithm, generates dual pulse control signal with frequency of 10kHz and adjustable pulse width (supports upper tube test timing), and the delay timeout self-cut time is set to 5s. The self-test module uses ADC to collect key voltage and current signals to judge the status of each component.

[0078] Driver module: A driver circuit board based on the UCC21750 chip, which realizes drive current expansion and multiple protection functions.

[0079] Protection module: Includes audible and visual alarm unit and emergency stop relay, receives fault signals from drive module and control module, and executes corresponding protection actions.

[0080] Example 2: Driver Circuit Board Design

[0081] like Figure 2As shown, the UCC21750 driver circuit board of the driver module includes a UCC21750 chip U1, a 4-channel MOS driver tube expansion unit (MOS tubes Q1-Q4, model IRF540N), a DESAT oversaturation deprotection unit, a port overvoltage protection unit, and an interference filtering auxiliary circuit.

[0082] UCC21750 chip connection: Connect the VDD pin of the UCC21750 chip U1 to a 15V power supply, ground the GND pin, and connect the IN+ and IN- pins to the filtered dual-pulse control signal output by the FPGA.

[0083] MOS driver expansion unit: The gates of MOS transistors Q1-Q4 are connected to the HO and LO output terminals of UCC21750 chip U1 respectively through current-limiting resistors R1-R4 (10Ω). The source is grounded, and the drain is connected to the gate of the IGBT to achieve superposition of drive current. The measured drive current can reach 55A, which meets the drive requirements of 14000A high-current IGBTs.

[0084] Interference filtering auxiliary circuit: including RC filter circuit and Schmitt trigger, to filter and shape the input control signal and improve the system's anti-interference capability.

[0085] Example 3: DESAT Oversaturation Protection Circuit

[0086] like Figure 3 As shown, the DESAT oversaturation de-protection unit consists of voltage divider resistors R3 (10kΩ), R4 (1kΩ), and filter capacitor C1 (1nF).

[0087] Circuit connection: Resistors R3 and R4 are connected in series between the IGBT collector and ground. The intermediate node is connected to the DESAT pin of U1 of UCC21750 chip through current limiting resistor R5 (1kΩ). Capacitor C1 is connected in parallel across R4 for filtering.

[0088] Working principle: When the IGBT is working normally, Vce is about 2V and the DESAT pin voltage is about 0.2V; when the IGBT is oversaturated, Vce rises to more than 10V and the DESAT pin voltage exceeds 1V. The UCC21750 chip U1 immediately shuts down the HO and LO outputs and outputs a fault signal to the protection module, triggering an audible and visual alarm and an emergency shutdown.

[0089] Protection response time: The time from detecting oversaturation to completely shutting off the drive signal is less than 10μs, effectively preventing IGBT damage due to oversaturation.

[0090] Example 4: Port Overvoltage Protection Circuit

[0091] like Figure 4As shown, the port overvoltage protection unit uses SMBJ18CA high-power TVS diode D1, which is connected in parallel to the 15V power supply port (between VDD and GND) of the driver circuit board.

[0092] TVS diode parameters: The breakdown voltage of the SMBJ18CA type TVS diode is 18V, the peak pulse power is 600W, and the response time is less than 1ns.

[0093] Protection mechanism: When a voltage spike of 20V or higher occurs at the power port, the TVS diode D1 quickly breaks down and conducts, dissipating the overvoltage energy to ground and limiting the port voltage to no more than 18V, thus protecting the UCC21750 chip U1 and other circuit components from damage.

[0094] Example 5: Test Procedure

[0095] The testing method of the present invention includes the following steps:

[0096] Step 1: System self-test

[0097] Before testing, the control module initiates a self-test function to check key parameters such as power supply voltage, drive circuit output impedance, and protection circuit response status. Testing can only begin after the self-test passes; otherwise, a fault message is output and testing is prohibited.

[0098] Step 2: Parameter Settings

[0099] Test parameters can be set through the human-machine interface, including test mode (double pulse test or short circuit test), pulse width, number of tests, delay time, etc.

[0100] Step 3: Test Execution

[0101] The FPGA control module generates a dual-pulse control signal, which is processed by an interference filtering algorithm and then output to the UCC21750 driver circuit board of the driver module to control the IGBT to turn on and off.

[0102] - Dual-pulse test mode: The energy storage capacitor bank discharges and generates a large current of 14000A through the load inductor to test the dynamic performance parameters of the IGBT.

[0103] - Short-circuit test mode: Trigger the short-circuit branch of the thyristor to realize the short-circuit condition of the IGBT and test the short-circuit withstand capability of the IGBT.

[0104] Step 4: Real-time monitoring

[0105] During the test, the DESAT oversaturation protection unit monitors the IGBTVce voltage in real time, the port overvoltage protection unit monitors the power port voltage, and the control module monitors the test duration in real time.

[0106] Step 5: Troubleshooting

[0107] When the following fault conditions occur:

[0108] - IGBT oversaturation (Vce exceeds the threshold)

[0109] - Port overvoltage (exceeding 18V)

[0110] - Test timed out (exceeded the set time)

[0111] - Self-test fault

[0112] The drive module or control module immediately outputs a fault signal to the protection module, which then activates an audible and visual alarm and triggers an emergency stop relay to cut off the main circuit power supply, thus achieving fault protection.

[0113] Step 6: Record the results

[0114] After the test is completed, the system automatically records the test data and waveforms and generates a test report.

[0115] Example 6: Protection Mechanism Verification

[0116] To verify the effectiveness of the protection mechanism of this invention, the following tests were conducted:

[0117] DESAT protection test: The system simulates an IGBT oversaturation state and successfully shuts off the drive signal within 10μs, protecting the IGBT from damage.

[0118] Port overvoltage protection test: When a 25V voltage spike is injected into the power port, the TVS diode responds within 5ns, limiting the voltage to 17.5V, and the protection circuit works normally.

[0119] Delay overtime protection test: Set the delay time to 5 seconds. When the test exceeds 5 seconds, the system will automatically cut off the drive signal to prevent damage to the IGBT from prolonged testing.

[0120] Test results show that the protection mechanism of the present invention is fast, reliable and effective, and can protect the safety of the test system and the IGBT device under test under various fault conditions.

[0121] 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.

[0122] 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 driving and protecting a 14000A IGBT with high current dual-pulse and short-circuit operation, characterized in that: Based on a hardware system consisting of a main circuit module, a control module, a drive module, and a protection module, an integrated application of circuit driving and protection is achieved. The specific method includes the following steps: S1: System self-test: The control module starts the self-test function to detect key parameters such as power supply voltage, drive circuit output impedance, and protection circuit response status. The test can only be started after the self-test is passed. S2: Parameter settings: Test parameters such as test mode, pulse width, number of tests, and delay time can be set through the human-machine interface; S3: Test execution: The control module generates a dual-pulse control signal, which is processed by the interference filtering algorithm and then output to the drive module to control the IGBT to turn on and off. The main circuit module provides a 14000A test current or short-circuit condition according to the test mode. S4: Real-time monitoring: The drive module monitors the IGBT collector-emitter voltage and drive circuit board port voltage in real time, and the control module monitors the test duration in real time. S5: Fault Handling: If any of the following occurs: IGBT oversaturation, port overvoltage, test timeout, or self-test fault, the protection module will be triggered immediately, the audible and visual alarm will be activated, and the main circuit power will be cut off. S6: Results Recording: After the test is completed, the system automatically records the test data and waveforms and generates a test report; The drive module is based on the UCC21750 chip and designed as a drive circuit board to achieve a drive current output of no less than 50A. It also integrates MOS drive tube expansion, DESAT oversaturation deactivation, and port overvoltage protection units.

2. The method for high-current dual-pulse and short-circuit driving and protection of IGBT 14000A according to claim 1, characterized in that: The MOS driver expansion unit of the driving module consists of at least four IRF540N type MOS driver transistors connected in parallel at the output terminal of the UCC21750 chip. The gate of the MOS transistor is connected to the output terminal of the chip through a 10Ω current-limiting resistor. The source is grounded and the drain is connected to the gate of the IGBT to form a current superposition loop. The measured driving current can reach 55A.

3. The method for high-current dual-pulse and short-circuit driving and protection of IGBT 14000A according to claim 1, characterized in that: The DESAT oversaturation protection unit of the drive module consists of a 10kΩ and a 1kΩ voltage divider resistor and a 1nF filter capacitor. The voltage divider resistor is connected in series between the IGBT collector and ground. The intermediate node is connected to the DESAT pin of the UCC21750 chip through a 1kΩ current-limiting resistor. The filter capacitor is connected in parallel across the 1kΩ voltage divider resistor. When the IGBT is oversaturated and the collector-emitter voltage rises above 10V, the chip immediately shuts off the drive output, and the protection response time is less than 10μs.

4. The method for high-current dual-pulse and short-circuit driving and protection of IGBT 14000A according to claim 1, characterized in that: The port overvoltage protection unit of the drive module is an SMBJ18CA high-power TVS diode connected in parallel at the 15V power port of the drive circuit board. The TVS diode has a breakdown voltage of 18V, a peak pulse power of 600W, and a response time of less than 1ns, which can limit the port overvoltage spike to within 18V.

5. The method for high-current dual-pulse and short-circuit driving and protection of IGBT 14000A according to claim 1, characterized in that: The main circuit module includes a 0-1000V adjustable DC power supply, a 1000μF / 1200V energy storage capacitor bank, a 1:1 high-frequency pulse transformer, a 50μH load inductor, and a thyristor short-circuit test branch. The dual-pulse test and short-circuit test modes are switched by a switching switch. The energy storage capacitor bank discharges through the load inductor to generate a stable 14000A test current.

6. The method for high-current dual-pulse and short-circuit driving and protection of IGBT 14000A according to claim 1, characterized in that: The control module uses a Xilinx Kintex-7 series FPGA chip, integrates a Kalman filter interference removal algorithm, and is equipped with an RC filter circuit and a Schmitt trigger to filter and shape the control signal; it has a built-in programmable delay timeout self-cut-off module, the maximum delay can be set to 10s, and the drive signal is automatically cut off after the timeout.

7. The method for high-current dual-pulse and short-circuit driving and protection of IGBT 14000A according to claim 1, characterized in that: The control module generates a dual-pulse control signal with a frequency of 10kHz and an adjustable pulse width. This control signal fully meets all the timing function requirements of the IGBT dual-pulse test tube.

8. The method for high-current dual-pulse and short-circuit driving and protection of IGBT 14000A according to claim 1, characterized in that: The protection module includes an audible and visual alarm unit and an emergency stop relay, which are linked with the DESAT oversaturation deprotection unit and port overvoltage protection unit of the drive module and the self-test module and timeout self-cut-off module of the control module to realize system-level fault alarm and emergency stop, forming a multi-level fault protection system.

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